If you are reading this report, you probably have knee or hip pain. That’s not surprising. When responding to a 2010 national health survey, almost a third of Americans 55 or older complained of having knee pain in the previous four weeks. Eleven percent reported having hip pain. Truth be told, nearly everyone will have some deterioration in these joints at some point in life.
Your knees and hips are your largest joints. While supporting your full weight as you stand upright, they must work in close coordination to provide the mobility most of us take for granted until injury, arthritis, or other conditions interfere. Of course, it’s possible to sidestep or delay some of these problems. For example, paring off excess pounds literally takes a load off knees and hips. Starting new activities gradually and progressing slowly rather than dramatically boosting activity levels helps, too. So does avoiding exercises that could harm these joints, such as deep squats and deep lunges.
Even the best laid plans may go awry, however. If you experience pain in your knees or hips, physical therapy, pain-relief medication, minor surgery, or some combination of these strategies may help ease it. Ultimately, though, many people find knee and hip problems become so intractable that the best solution is replacing a worn-out knee or hip with a mechanical joint.
Joint replacement can help people remain independent and active. In the United States, doctors perform about 676,000 knee replacements and 327,000 hip replacements annually. Many people, young and old, gain pain relief and mobility from these procedures.
Medical care is constantly changing. Doctors used to follow these surgeries by immobilizing the joint with a plaster cast. Today, you can begin rehabilitating your knee by starting physical therapy not long after waking up from surgery. More surgeries are performed through tiny incisions using a tool called an arthroscope, often on an outpatient basis. Pain relief has progressed to include drugs that tackle the twin problems of pain and inflammation.
These advances translate into vastly improved lives. Recently, after performing a rotator cuff repair on a patient’s shoulder, I reminded him to come in for a follow-up visit for his hip replacement. Looking surprised, he admitted that he’d completely forgotten he’d had a total hip replacement four years earlier. He’d since returned to an active lifestyle and the new hip had become a part of him.
The proper care can help you reclaim the life you enjoy, too. Whether you’ve just started to experience pain or have been battling it for years, this report will help you make informed decisions about staying active and independent for years to come.
Scott D. Martin, M.D.
Knees in motion
Knees suffer injury more often than any other joint. What makes the knee so vulnerable? One factor is anatomy. Often described as a simple hinge, the knee is actually a complicated network of bones, cartilage, muscles, tendons, and ligaments (see Figure 1).
Figure 1: Strong and flexible
The knee is more than a simple hinge. Along with the strength to raise and lower your body weight, this joint also has supporting structures to allow you to twist and turn.
The knee joint is the junction of three bones:
• the thighbone, or femur
• the shin bone, or tibia, the larger front bone of your calf
• the kneecap, or patella.
At its lower end, the femur divides into two rounded knobs called condyles, which support the body’s weight on the bone of the lower leg, the tibia. The top of the tibia is rather flat with a middle bump. Unlike the beautiful fit between bones found in many other joints, the knee’s mismatch in shape allows for complex movement but is quite unstable, like two doorknobs balanced on an uneven plate.
The patella is a small, flat bone that floats in front of the knee joint. The patella moves within a groove between the two condyles of the femur. Your patella protects other knee structures and applies leverage to help straighten the joint.
Separating the bones of the knee are two rubbery cartilage pads known as menisci. Named for their crescent-moon shape, the menisci curve around each side of the tibia’s top, serving as shock absorbers and helping the bones fit together. Menisci are made of tough, elastic cartilage, but are susceptible to injury from the pressure of the thighbone and shin bone they cushion. Excess body weight can accelerate degenerative changes in the joints, and studies have shown an association between obesity and arthritis of the knee. The ends of the bones themselves are coated with articular cartilage, slippery tissue that smoothes the movement of the joint.
Muscles power the movement of your knees. These muscles include
the quadriceps, a set of four muscles often called the “quads,” that runs up the front of your thigh and contracts when you straighten your knee. These muscles work hard when you get up from sitting or squatting.
the calf muscle (gastrocnemius), which helps the knee bend.
the hamstrings, three muscles in back of your thighs that contract when you bend your knees, helping support your weight as you sit down, and helping to extend the hip as you get up.
Tendons connect muscle to bone and transfer muscle power to the bone to create movement. For example, the quadriceps tendon connects the quadriceps muscle to the patella and provides the power to extend the leg.
Ligaments are tough, fibrous tissues that connect bones or cartilage at a joint, allowing movement within a safe range. On the inner side of the knee, a large ligament called the medial collateral ligament, or MCL, connects the femur to the tibia on the inside (big-toe side) of the knee joint, limiting sideways motion. The lateral collateral ligament does the same on the outside (little-toe side), connecting the femur to the small bone of the calf, or fibula. Deep within the joint, the anterior cruciate ligament, or ACL, connects the femur to the tibia in the center of the knee; it keeps the joint from rotating too far or letting your shin get out in front of your thighbone. Crossing behind that ligament is the posterior cruciate ligament, which keeps the shin bone from falling out of place behind the knee.
Other anatomical elements
The entire knee joint is located within a bag-like capsule with the consistency of thick plastic wrap, called the synovium. It is a layer of cells lining the capsule, and produces synovial fluid, a sticky, translucent liquid that lubricates the joint and minimizes friction. It also helps protect the joint by forming a viscous seal that enables abutting bones to slide freely against each other but resist pulling apart. This seal breaks when the joint is moved quickly or forcefully, producing a popping sound.
Places where tendons, muscles, and bones cross paths are also subject to friction. These sites are protected by bursae, cushioning sacs containing a little oily lubricant.
Movement in the knee is like the hinge on a jewelry box: it opens in only one direction. Forcing it beyond a certain point causes damage. A healthy knee allows almost 150 degrees of movement; you can straighten your leg or bend it until your calf meets the back of your thigh, but you can’t bend your knee in the other direction so your shin meets the front of your thigh. But unlike the jewelry box hinge, in which any wobble is undesirable, your knee can slightly rotate or move from side to side.
Diagnosing knee problems can be complicated, in part because of the large number of possible causes of knee pain. Patients are not always able to pinpoint the exact location of their pain, and injuries may not be clearly visible on imaging tests. In some situations, a physical examination and the information you provide are sufficient. But most diagnoses require at least an x-ray, and in some cases the doctor may recommend more advanced imaging and laboratory tests to determine the cause and extent of damage. But be aware that even expensive tests such as magnetic resonance imaging (MRI) may not be conclusive or even useful (see “Testing for knee and hip problems”). While MRI may reveal an abnormality, it may not be the source of the pain. In fact, studies show that MRI often reveals abnormalities in patients who have no pain.
Your medical history
More important than any test is an accurate description of your symptoms. During the exam, the doctor asks many questions about your pain and other symptoms.
Click, clack, pop: When to worry about noisy joints
Do your hips and knees click, snap, or pop? If there’s no pain or swelling, the noises are not usually a sign of trouble. You may hear a tendon moving across a joint. Or you may have momentarily (and harmlessly) broken the seal of synovial fluid that fills the joint capsule. The sound could also be the release of nitrogen gas from a joint moved slightly out of position (like a cracking knuckle). It’s a different story, however, if the noise occurs at the moment of injury, or if pain or swelling accompanies it; in that case, there may be joint damage that needs medical attention. In addition, a grating sound, called crepitus, may be a sign of arthritis.
Where does it hurt? Try to describe the location of the pain as precisely as possible. This is not always easy. In large joints your pain may be diffuse, radiate from one area to another, or seem to come from a nearby muscle. Your doctor may ask you to point to one spot on your knee where you feel the greatest amount of pain.
How does the pain feel? Does it ache, stab, or burn? Have you had similar pain in other joints?
When did the pain start? Did the pain occur gradually over time or did it occur suddenly, following a fall, other injury, illness or fever, or a change in activity, for example? If you were injured, did the knee pop or “give out”? Could you walk immediately afterward? Was there swelling? If you have injured that knee before, mention it. Even if it wasn’t bothersome or got better, a previous injury might have caused significant damage—and a relatively trivial event could have worsened it enough to cause symptoms.
When does the pain occur? Is it “getting started” pain—worse when you first stand up and walk? Does it hurt more in the morning and then ease up? Is it worse after a certain activity? After you walk a certain distance?
What helps? Does it bother you in bed but ease up once you’re up and about? Does pain with activity go away when you sit and rest?
Are there other symptoms? Do you have trouble straightening or bending your knee? Does it lock up or give out?
Expect also to answer questions about other illnesses and medications, which may increase the risk of certain joint problems.
Examining the knee
Your doctor will look for discoloration and swelling and assess how your knees function. While you are in various positions—sitting with knees dangling, lying on your back, or lying on your stomach with knees flexed behind you—the doctor will move your legs to assess each knee’s range of motion, muscle strength, abnormal movements within the joint, and telltale pain or sounds that occur with various maneuvers. Even if only one knee hurts, the doctor will examine both for comparison. If the knee is too swollen to evaluate thoroughly, your doctor may schedule a follow-up appointment.
Your doctor may want to assess the relationship of your knees to your hips by measuring your Q-angle (see Figure 2). The Q-angle typically ranges from 0 to 16 degrees, with men usually at the lower end. An abnormally high Q-angle places you at greater risk of patellofemoral pain syndrome and certain injuries, such as tears of the ACL. The doctor will also evaluate nerve function and circulation in your legs, watch you walk, and follow up on any symptoms of general illness. He or she may schedule further tests at this point.
Figure 2: What’s your Q angle?
It’s not obvious, but your thighbone (femur) and your shin bone (tibia) are not aligned in a straight line. The line of the femur and the line extending from the ankle through the kneecap (patella) form what is known as the Q-angle. Women usually have a more pronounced Q-angle than men and, as a result, may be more susceptible to tears in the anterior cruciate ligament.
Women and knee vulnerability
Some knee injuries occur far more often in women than in men. One example is injuries to the ACL, the strong, stabilizing central ligament of the knee, which can be strained or torn by a sudden pivot or abrupt stop, or by landing poorly after a jump (see “Ligament damage in the knee”). According to a Journal of Bone and Joint Surgery study published in 2012, ACL ruptures occur two to five times as often in women as in men.
Most likely, a combination of anatomy, hormones, and differences in fitness training helps explain the disparity. In the 2012 study, the researchers found that the outside of the knee joint of most of the women—injured or not—and of all of the injured men had the same shape. MRI imaging showed that a spot called the tibial plateau on the upper portion of the shin bone at the joint was far rounder and shorter than usual, which could affect knee stability.
As a group, women’s knees are different from men’s in other ways, too. Women’s hips tend to be wider, so the thighbone reaches the knee at the larger Q-angle, sometimes giving a slightly knock-kneed appearance. Of the four quadriceps muscles, the three extending to the outside of the hip are often stronger, tugging the kneecap in that direction—sometimes enough to cause pain (see “Patellofemoral pain syndrome”).
Estrogen is a suspect in women’s knee vulnerability. Some (but not all) studies show that female athletes injure their knees more frequently at ovulation, when estrogen levels are high. Researchers speculate that high levels of estrogen and other hormones, which make ligaments more flexible during pregnancy, might also make knee ligaments more prone to injury. Ordinarily, flexibility is a good thing because it allows tissues to stretch farther without tearing. But if ligaments and muscles supporting the knee are overly flexible, they may absorb less of the stress of an impact. This forces the joint to absorb more of the impact, possibly rupturing the ACL.
Other experts suggest that training techniques and muscle use among female athletes may be the culprit. Women tend to run in a more upright position, strongly contracting the quadriceps muscles on the front of their thighs (rather than their often-weaker hamstrings) and putting more strain on their ligaments. When jumping, women tend to land more on one leg or with straighter legs.
What can women do to reduce the risk? If you have broader hips or a tendency toward knock-knees, you probably have a high Q-angle (see “What’s your Q-angle?” left). Wearing the right shoes or arch supports can reduce it somewhat, lowering your risk of injury. When exercising, strengthen and stretch both your quadriceps and hamstrings. Learn to stretch your iliotibial band, which runs from your hip to your knee (see Figure 7). If you’re involved in basketball or other jumping sports, find a knowledgeable coach and learn safe ways to land, pivot, and stop (especially quick stops before shooting a basketball).
Assessing the role of body weight
If you’re overweight, your primary care physician will help assess the role your weight plays in your knee pain and recommend a plan of treatment accordingly. Most likely, a weight loss plan will be helpful. Many knee problems—including osteoarthritis—can be avoided or eased by attaining a healthy weight.
Carrying extra weight is directly related to knee pain. A 2008 review article in the journal Obesity found that obesity (defined as having a body mass index of 30 or above) leads to pain, limits activity, and increases the risk of needing a total knee replacement. Previously, an Obesity Research study of 5,700 Americans over age 60 showed that the more obese a person was, the more likely he or she was to experience knee pain. About 56% of severely obese people had significant knee pain, compared with 15% of people who were not overweight.
Such findings are not surprising when you consider that with each step on level ground, you put one to one-and-a-half times your body weight on each knee. So a 200-pound person can put 300 pounds of pressure on each knee at every step. Off level ground, the news is worse: each knee bears two to three times your body weight when you go up and down stairs, and four to five times your body weight when you squat to tie a shoelace or pick up an item you dropped. If you’re 50 pounds overweight, the simple act of going downstairs and squatting to move clothes from the washer to the dryer puts hundreds of extra pounds of force on your knees.
Overuse injuries of the knee
The knee can be compared to an expensive sports car—a finely tuned machine that is capable of great power but also highly vulnerable to breakdown. Over time, many things can go awry as a result of illness, mishap, and misuse of the joint. Overuse injuries occur over a period of time rather than after a single injury or illness. They may result from repeated overwork or from doing too much in a single day. As we age, overuse injuries become more common. Even normal age-related changes, such as reduced muscle mass and bone density, can make you more prone to knee injury as you get older.
Symptoms of bursitis
Swelling on top of or in front of the kneecap (prepatellar) or below the kneecap (infrapatellar)
Warmth and tenderness
Pain when you bend or straighten your knee
Pes anserine bursitis may cause distinctive pain as follows:
Pain located a few inches below the kneecap, in the center, or behind
Increase in pain when you climb stairs or exercise
Pain that radiates to the back and inside of your thigh
Pain when your knees touch as you lie on your side
Small fluid-filled sacs called bursae cushion the movement of bones against muscle, skin, or tendons. Bursitis occurs when one or more of these sacs become inflamed.
Irritation from prolonged kneeling can result in bursitis involving either the sac that lies between the front of your kneecap and your skin (called prepatellar bursitis or “housemaid’s knee”) or the bursa just below the kneecap (called infrapatellar bursitis). People who kneel on the job or during prolonged gardening and housecleaning are susceptible to these forms of bursitis. You may also develop prepatellar bursitis if you hit the front of your knee in an accident or when diving to the floor playing sports.
Pes anserine bursitis involves the lubricating sac between your shin bone and the hamstring tendons at the inside of your knee. Just walking may stress the pes anserine bursa if you are obese, have tight hamstring muscles, have knees with a natural turnout, or have changed how you walk in response to another type of joint damage (such as osteoarthritis). Runners are susceptible, particularly if they neglect to stretch and warm up properly, if they quickly increase their mileage, or if they train on hills. Repeatedly kicking a ball also irritates this bursa.
To check for bursitis, your doctor will gently press on the skin over the bursa to detect tenderness. He or she may inject a bit of local anesthetic into the sac. If the pain disappears, that’s strong evidence of bursitis. You may need imaging tests to distinguish pes anserine bursitis from other conditions such as a fracture or meniscal tear. If you have symptoms of infection (fever, persistent redness, rash, or swelling) your doctor may withdraw a little fluid from the bursa to check for bacteria. Infection is very uncommon in the pes anserine bursa, but the prepatellar bursa can become infected in people who spend a lot of time on their knees.
Treating bursitis. Bursitis is treated with rest, ice, and compression to reduce swelling (see “RICE”). To relieve pain, doctors typically recommend acetaminophen (Tylenol) or one of the other over-the-counter pain relievers known as nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil, Motrin) or naproxen (Aleve). The doctor may also give a corticosteroid injection into the bursa to reduce inflammation.
You’ll need to avoid activities that aggravate the condition during the healing process, which usually lasts two to six weeks. If the fluid in the bursa shows signs of infection, you’ll need to take antibiotics, and your doctor may remove fluid daily to keep down swelling. In extreme cases, the swollen bursa is removed surgically.
Your doctor may also recommend physical therapy to strengthen and stretch the quadriceps, the large muscle in the front of your thigh (see Figure 3), and the hamstrings on the back and inner thigh. A physical therapist can also show you how to protect your knee during sports and daily activities. If your normal stance puts pressure on the pes anserine bursa, using flexible, over-the-counter arch supports in your shoes may reduce it. To prevent prepatellar bursitis, wear protective kneepads (such as roofer’s pads or gardening pads) while kneeling or while playing sports likely to involve hitting the knees.
Figure 3: Knee strengthening exercises
Straight-leg raise: To protect your knees, do this exercise to strengthen your quadriceps, the large muscle in the front of your thigh. Lie on your back and tighten the thigh muscles of one leg with your knee fully straightened. Lift your leg several inches and hold for 10 seconds. Lower slowly. Repeat until your thigh feels fatigued, then switch to the other leg.
Wall sit: This exercise also strengthens the quadriceps. While standing with your back against the wall, bend your knees, lowering yourself into a sitting position. Do not lock your knees. Hold this position for 20 seconds. Repeat.
Bursitis can recur if you don’t take preventive measures after it heals. For example, get up and stretch your legs regularly if you have to work on your knees for long periods of time, stretch your legs before and after you exercise, vary your workouts to rest your knees, and elevate and ice your knees after you exercise or spend a long time on your knees.
Symptoms of tendinitis
Pain above or below the kneecap where the tendons attach to bone
Pain that recurs with particular activities and eases with rest
In severe cases, pain that no longer improves with rest
In some cases, a constant ache that disrupts sleep
Tendinitis is inflammation in a tendon. It usually results from overuse. The affected tendon continues to function, at least for a while, but there is recurrent pain. You may develop tendinitis in the knee if you engage in high-intensity activities such as running or basketball on the weekend but do little to maintain your conditioning during the week. Also, excess weight puts additional stress on the patellar tendon and can contribute to tendinitis.
With age, tendons become stiffer and more prone to tendinitis, while supporting muscles become weaker and less able to provide protection. Inflexible hamstrings and quadriceps make you more susceptible.
Tendinitis in the knee most often affects the patellar tendon, which connects the kneecap to the tibia, although it may also occur in the quadriceps tendon, which connects the front quadriceps muscle to the patella. Dancers, runners who train vigorously, and athletes who jump a lot are subject to patellar tendinitis, sometimes called “jumper’s knee.”
To diagnose tendinitis, the doctor gently stretches the tendon and probes for tenderness below and above the kneecap. Testing for characteristic muscle tightness (often in quadriceps, hamstrings, and heel cords) helps with the diagnosis and provides strategies for rehabilitation. X-rays usually aren’t needed.
Acetaminophen or NSAIDs for pain relief?
The first line of treatment for many knee and hip problems includes taking over-the-counter pain relievers. Acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen are the most common options. These medications have a variety of side effects, so it’s important to discuss your personal health risks with your doctor when considering long-term use for chronic conditions such as osteoarthritis.
Acetaminophen (Tylenol and other brands) is usually effective for mild pain and is easy on the stomach. However, it does have risks, especially for the liver. To be on the safe side, don’t exceed the recommended maximum per day, generally set at 4 grams (4,000 milligrams), which is the equivalent of eight extra-strength Tylenol tablets. Avoid acetaminophen if you drink more than a moderate amount of alcohol on a regular basis or if you have liver disease.
NSAIDs such as aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve, Anaprox), and several others may be more effective than acetaminophen for certain conditions because they not only relieve pain but also reduce inflammation. But NSAID medications have side effects, the most common of which are gastric bleeding and ulcers. You can ask your doctor about taking a proton-pump inhibitor such as esomeprazole (Nexium) or lansoprazole (Prevacid) to reduce the risk of gastric bleeding and ulcers.
Taking acetaminophen along with an NSAID may provide equivalent pain relief while using a lower dose of both medications, thus minimizing side effects.
Treating tendinitis. For the first few days, tendinitis is treated with rest, ice, over-the-counter pain relievers, and often a knee support. After that, you can resume gentle activities that don’t aggravate the area. If pain doesn’t improve with rest, your doctor may apply a steroid solution over the area and use electrical stimulation to help the medication reach the tendon and reduce inflammation (see “Ultrasound, phonophoresis, and iontophoresis”). In many cases, tendinitis goes away in a few weeks or months. But if none of these remedies work and the pain persists for more than a year, surgery is sometimes performed to remove abnormal areas of the tendon.
Rehabilitation for tendinitis includes exercises to improve flexibility and address muscle imbalances that place extra stress on the tendons (see Figure 3). You can usually resume normal activities in a few days and more demanding athletic activities in a few weeks, after the pain and swelling are gone and you have regained muscle strength.
Iliotibial band syndrome
Symptoms of iliotibial band syndrome
Pain in the upper outside of the knee
Pain along the IT band, from the hip to below the knee
Pain on the outside of the hip exacerbated by pressure, such as when lying on the affected side
Dull, sharp, or stinging pain
Pain that arises gradually or after a single intense workout
The iliotibial (IT) band is a thick cord of tissue extending from the hip bone down the outside of the thigh to the tibia. When the knee bends, the IT band slides over the outside knob of the femur. If it becomes inflamed, the outside of the knee hurts.
In older people, IT band syndrome usually occurs when something else, such as a bad back or another joint problem, has thrown off the gait. But IT band syndrome can occur in anyone who increases running mileage too rapidly or overdoes it while cycling, skiing, or playing soccer. The syndrome is more common in those who fail to warm up properly and those who have tight IT bands, unbalanced leg muscle strength, high or low arches, or unequal leg lengths.
To diagnose IT band syndrome, the doctor presses on the outside femur knob of your knee while you flex and extend your leg. If pain is greatest with the knee flexed about 30%, that’s a telltale sign. The IT band may also be swollen or thicker where it passes over the femur.
Treating iliotibial band syndrome. The first line of treatment for IT band syndrome is resting the joint, applying ice, taking over-the-counter NSAIDs such as ibuprofen or naproxen, and reducing or eliminating the aggravating activity. If running or playing basketball or tennis is aggravating the problem, stop to give the area time to heal. Women should avoid wearing shoes with heels higher than an inch. If pain occurs while you sleep, try a memory foam or gel mattress cover, which help relieve pressure.
In physical therapy, you learn to stretch your IT band (see Figure 7), improving the balance, flexibility, and strength in your quadriceps muscles and hamstrings. While you are being treated, you can maintain conditioning by substituting other activities that don’t stress the knee, such as swimming, aqua jogging, riding a stationary bike with little resistance, light walking, using an elliptical machine, and using cardiovascular fitness machines that involve only arm movements.
If symptoms do not improve, the doctor may inject a corticosteroid medication into the band to relieve pain and inflammation. Surgery is not usually required. Depending on severity, IT band syndrome may take several weeks or more to heal. If you’re overweight, losing weight can reduce the likelihood of the syndrome returning. Other steps you can take to prevent recurrence include adding stretches for the outside of your thigh to your warm-up routine, cutting back on your training regimen, and avoiding running on uneven surfaces or on circular tracks (which are often slanted, causing increased stretching of the IT band on the downhill leg). Eliminating other factors, such as altered gait resulting from back or hip pain, can also help.
Tears in supporting tissues
The supporting tissues surrounding the knee can split or tear under the pressure of injury or overuse.
Symptoms of a ruptured knee tendon
Disabling pain at the top or bottom of the kneecap
Difficulty or complete inability to straighten the knee
Popping or snapping at the moment of injury
When you suddenly contract your quadriceps to their maximum capacity—say, if you stumble going down stairs and desperately try to stay upright—the force can be enough to tear the quadriceps tendon connecting your muscle to the kneecap. This type of injury is common in recreational athletes over age 40, particularly basketball players. Your risk is greater if you have diabetes, other hormonal disorders, or kidney failure. A ruptured tendon can be quite disabling temporarily and usually requires surgery. Recovery can take several months.
Less commonly ruptured is the patellar tendon, which connects the kneecap to the tibia (making it a ligament, even though it’s commonly called a tendon). Although this usually occurs in athletes landing badly after a jump, occasionally a fall unrelated to sports is to blame. The same underlying conditions raise the risk, although most patellar tendon ruptures occur in people under age 40.
A tendon rupture needs immediate attention. To diagnose this injury, your doctor may feel the gap in the quadriceps or patellar tendon by pressing the area just above or below your kneecap. X-rays won’t show the tendon well, but may show that your kneecap is slightly out of place because it has lost connection with the muscle. The kneecap may sit abnormally low (called patella baja) in a quadriceps tendon rupture, or too high (called patella alta) in a patellar tendon rupture. MRI, an imaging method that shows soft tissue (see “MRI”), can reveal a partial or complete tear. If both tendons rupture, an unlikely occurrence, the doctor will test for underlying diseases such as kidney failure and diabetes.
Treating a ruptured tendon. At first, your doctor will place your knee in a brace to immobilize it while you rest the leg and use ice to counter pain and swelling. If the tear is partial and you can extend your leg, surgery may be unnecessary and your doctor may place your leg in a cast for healing.
For a complete rupture, you’ll probably need surgery as soon as is practical (within a week, before the muscle retracts and creates additional problems). The procedure involves open surgery, not arthroscopy. During the operation, the surgeon rejoins the tendon’s torn ends and stitches them in place, often anchoring them to small holes drilled in the kneecap. Better surgical techniques, combined with more aggressive physical therapy following the procedure, are among the advances in this procedure.
Following surgery, the leg is held straight in a brace for several weeks. After being immobilized, a repaired tendon will be quite weak, and you’ll need crutches to get around. Under the direction of a physical therapist, you can start building up strength after about a week by gradually putting some weight on the leg. You should do this carefully and in small increments, however, to avoid rupturing the tendon again. After three weeks, your physical therapist will show you exercises aimed at strengthening the quadriceps and calf muscles and help you slowly increase how much you bend the knee. It may be eight to 12 weeks before you can walk normally, three months before you can run again, and six months or longer before you can jump.
Symptoms of a meniscal tear
Stiffness and swelling in the knee
Pain and tenderness along the joint line or general knee pain
Catching or locking of the knee
Among the most frequently injured parts of the knee are the shock absorbers called menisci, which provide cushioning between the thighbone (femur) and shin bone (tibia; see Figure 4).
Figure 4: Meniscal tear
When the shock-absorbing cartilage in the knee is torn by injury or worn ragged by use, the result is called a meniscal tear. Stiffness and a vague sensation that the knee is not moving properly often result.
Unfortunately, the menisci can tear. As you age, the menisci weaken and fray. Even such a simple motion as getting in and out of a squatting position or rising from a low chair can tear a meniscus. MRI imaging has revealed that damage to the meniscus is extremely common and often causes no pain. About 30% of people ages 30 to 40 have meniscal tears, and about 50% of people over age 50 have them but experience no pain.
In younger people, tearing a meniscus is usually caused by a strong, twisting force. This might occur as you round the bases in softball or pivot left to throw a basketball while your feet are facing right. Meniscus damage often accompanies a tear of the ACL in the front of the knee (see “Ligament damage in the knee”). In people with osteoarthritis, meniscus damage can occur with no identifiable injury as part of the gradual cartilage degeneration process. The same genetic predisposition for arthritis may also contribute to meniscal deterioration.
To diagnose a meniscal tear, the doctor will ask about pain and movement. Is your knee most comfortable when slightly flexed? Is it hard to straighten your leg? Your doctor will maneuver your legs as you sit, lie on your stomach, and lie on your back to observe any pain, popping, or grinding in the meniscal area.
MRI can reveal the presence of a torn meniscus, but it doesn’t reveal whether a tear is new or whether it’s the cause of your symptoms—yours may have been torn for years and never bothered you. Because MRI is expensive, the test is reserved for times when the diagnosis is in doubt or the results will influence treatment. Plus, a torn meniscus can still function and may be a better option than having it surgically removed. Unless all of the conditions below are met, a meniscal tear is unlikely to be treated with surgery:
Your pain came on suddenly and is localized to the joint line where the meniscus commonly tears.
MRI and clinical examination both suggest there is a tear.
An x-ray or MRI indicates there is little or no arthritis in your knee.
You have symptoms of locking or catching in the knee.
More conservative treatments such as steroid injection and physical therapy have failed.
Treating a meniscal tear. The goal is to relieve pain, restore normal motion, and preserve as much of the meniscus as possible. Initial treatment includes rest, ice, and compression, along with NSAIDs. Steroid injections may also be used. A definitive evaluation may be deferred a week or so until swelling subsides. At that point, if your knee is stable and doesn’t lock, you may need no further treatment.
Whether a small tear heals depends on its location; the outer rim of the meniscus is well supplied with blood and should heal, while other portions have little or no blood supply and can’t repair themselves. If pain persists, depending on the size and location of the tear, doctors may choose one of three surgical approaches: repair, removal, or replacement. Most surgeries can be performed arthroscopically on an outpatient basis and with a choice of anesthesia.
During the procedure, the surgeon stitches the tear if possible, although most tears in people over age 45 cannot be repaired because there are fewer blood vessels in the menisci with age. If part of the ripped meniscus is blocking normal joint action, the surgeon removes that section. Before the shock-absorbing role of the menisci was fully appreciated, doctors used to remove the damaged meniscus entirely; now they remove as little as possible. Even if your menisci have weakened the tissue is worth keeping if possible. If a severely damaged meniscus can’t be repaired, however, the surgeon may remove it, since there is no value in keeping it in place and removing it may reduce pain and improve mobility. After all, if you kept broken-down shock absorbers on your car, you’d still have a bumpy ride.
A third, though uncommon option currently under investigation is a meniscal transplant. It is only appropriate for limited cases, such as when a young patient has a well-preserved knee joint and deficient meniscus. Meniscal transplants are performed arthroscopically with regional anesthesia, using meniscal tissue from human donors. The procedure has a success rate of 70% to 90% but the numbers are limited and considered preliminary. Artificial meniscal implants may be an option in the future—for example, research is under way on a form of synthetic meniscal scaffold, but with limited clinical results so far.
After surgery, you’ll return home on crutches for a few days. You can resume normal activities after about a week and start more demanding activities such as sports in about four to six weeks. Recovery and rehabilitation take longer after a meniscal transplant; during recovery, you’ll need crutches for about three to four weeks and will need to wait three to four months to resume running and possibly five to six months before returning to other recreational activities. Rehabilitation includes exercises to improve the strength and flexibility of muscles surrounding the knee (hamstrings, quadriceps, and calf) and the range of motion of the joint.
After a meniscal tear, strengthening your quadriceps will help make up for lack of the knee’s built-in shock absorber. Light exercise that does not put a lot of weight on the knee—such as swimming, riding a stationary bike, or using an elliptical machine—can help rebuild strength.
Ligament damage in the knee
Symptoms of ligament damage
Symptoms of an MCL injury:
Pain and tenderness on the inside of the knee
Wobbling of the knee or knee giving way
Sensation of the knee opening up with each step (in severe injuries)
Symptoms of an ACL injury:
A popping sound at the time of injury
Swelling, which may cause pain
Instability, ranging from wobbling to an inability to get up
Of the four major ligaments that support the knee joint and help control knee motion (see Figure 1), two are most easily ruptured or torn: the medial collateral ligament (MCL) and the anterior cruciate ligament (ACL).
Each year, approximately 200,000 people in the United States injure their ACL. A bit less than half of those injuries are ruptures. ACL injury is sometimes accompanied by MCL injury on the inside of the knee. Women are more than twice as likely as men to experience an ACL injury (see “Women and knee vulnerability”). People who participate in sports such as basketball, football, skiing, and soccer—which involve changing direction rapidly, stopping suddenly, or landing awkwardly—are at high risk for ACL injury as well. About half of ACL injuries occur together with damage to the meniscus, articular cartilage, or other ligaments. Football quarterback Tom Brady of the New England Patriots suffered injury to both his ACL and MCL in the 2008 season, and basketball player Kendrick Perkins of the Boston Celtics tore his ACL in the 2010 playoffs.
Treating MCL damage. Once your knee is wrapped in a bandage, ice and elevation will help reduce swelling. Take NSAIDs to help relieve pain and inflammation. A brace may help you totally rest the joint. Limit physical activity until the pain and swelling go away. Surgery is rarely needed unless the ACL is also injured. Physical therapy can gradually improve your range of motion and the strength and flexibility of your quadriceps and hamstrings. Depending on the severity of the injury, it may take as little as a week or more than two months before you can return to normal activities.
Treating ACL damage. The first steps are the same as for MCL damage: use ice and compression, and elevate your knee whenever you sit or lie down. For pain relief, start with over-the-counter NSAIDs.
To rest your knee, use a brace to keep it straight and crutches to keep weight off your leg. Although the ACL cannot heal, one in three people can regain enough strength in the knee to return to nondemanding activities without surgery. But this isn’t easy. It may require a year of rehabilitation before muscles are strong enough to compensate for the loss of ACL-provided stability. Even so, your knee may sometimes pop out of joint. Your doctor may suggest an ACL brace to use during occasional strenuous activity. If you wish to return to activities involving jumping and pivoting, you will probably need surgery.
To determine whether you should have surgery, you and your doctor will need to consider your age, your activities, how unstable your knee is, whether your ACL is partially or completely torn, and other injuries. Patients who undergo ACL reconstruction surgery have long-term success rates of 82% to 95%. However, the reconstructed ACL fails or becomes unstable in about 8% of cases.
ACL surgery lasts about two hours and is usually done arthroscopically. After drilling holes in the bone where the ACL attaches, the surgeon inserts either a transplanted tendon from your own patella or hamstring, known as an autograft, or piece of tissue from a donor, called an allograft. The surgeon fits the bone-ends of the tendon into the holes and screws them into place. Newer surgical techniques have allowed surgeons to more precisely place the end of the new tissue inside the joint for greater stability.
After surgery, you’ll go home with crutches and may use a brace that holds your leg straight (locked in the extended position) or unlocked for a sitting position. During the first two weeks after surgery, you’ll ice your knee regularly to reduce swelling and pain. Physical therapy will focus on improving your strength, stability, and movement. Your muscle strength dictates when you may reintroduce various activities, usually at least 10 weeks after surgery for normal activities and about six months for sports.
Both before and after surgery, you need to participate in physical therapy to gain as much strength and range of movement as possible. Even if you don’t have surgery, you must make an ongoing commitment to strengthening your knee muscles.
When you put your weight on one leg to step out of your car or go up a stair, does your knee hurt? Kneecap pain is common because your full body weight must ride smoothly up and down the interface between the thighbone and kneecap each time you step up or down. When something goes wrong, pain will quickly follow.
As you bend and straighten your knee, the patella (knee cap) rides up and down a groove in the front of the femur called the trochlea. This movement of the patella within the trochlea is referred to as patellar tracking. The patella is covered by the quadriceps tendon and is firmly attached to the strong quadriceps muscle. At the bottom, it connects to the tibia via the patellar tendon. A variety of conditions can throw off the patella’s position and movement, causing pain and other symptoms.
Patellofemoral pain syndrome
Symptoms of patellofemoral pain syndrome
Pain in the front and center of the knee during and after physical activities, especially those that repeatedly put weight on a bent leg (running, step aerobics, basketball)
Pain from prolonged sitting (“moviegoer’s sign”)
Knee puffiness after activity
Patellofemoral pain syndrome is characterized by pain in the front of the knee, under and around the kneecap. The term is often used interchangeably with “runner’s knee” or “anterior knee pain.” The term “runner’s knee” is particularly apt; patellofemoral pain syndrome accounts for 16% to 25% of all injuries in runners. But patellofemoral pain syndrome is not restricted to athletes. In fact, it is the most common diagnosis given to patients who visit their doctor’s office complaining of knee pain. The condition is more common in women over 40 and in physically active teenage girls.
Patellofemoral pain often results from alterations in patellar tracking. Three major factors are involved, although their relative contributions can differ greatly from person to person:
Malalignment. People with a high Q-angle (see Figure 2) are at higher risk, as are people whose arches flatten with each step.
Muscle imbalance and tightness. Tight hamstrings, calves, and hip muscles increase the pressure between the kneecap and the thighbone. Of the four muscles that make up the quadriceps, three pull the kneecap toward the outside; if the innermost quadriceps muscle is relatively weak, this can create tracking problems with the knee cap.
Overuse. Bending the knee moves the patella tighter against the femur. Patellofemoral pain syndrome worsens with activities that put weight on the knee while it is bent, such as squatting or running on steps and hills.
During the exam, the doctor feels your kneecap to look for tender spots, abnormal movements, and grinding under the kneecap as it moves (called crepitus), and to determine how easily the kneecap moves out of regular alignment. The doctor assesses the alignment of both knees and legs. Your doctor may look at the bottom of your shoes to see if the sole is worn out more in certain places, which may reveal whether your feet and ankles fall inward (pronation) or your feet need more arch support. X-rays and other imaging tests are reserved for later, if you fail to see improvement after several weeks of treatment.
Treating patellofemoral pain syndrome. A rehabilitation plan prescribed by a doctor or physical therapist will be important to regaining strength and range of motion. Rest your knee, apply ice packs, and keep your knee elevated. Take acetaminophen or NSAIDs to help relieve pain. Substitute low-impact activities—such as walking on level ground, swimming, or using a stationary bike or elliptical trainer—for high-impact activities like running or jumping. After activity, ice the knee for 10 to 20 minutes. Exercise to strengthen your quadriceps muscles (see Figure 3), adding small ankle weights after two weeks. Stretch to increase the flexibility of your hamstrings, calves, and hip muscles. Your physical therapist can identify which areas need the most attention. Arch supports or better-fitting athletic shoes may be helpful as well.
It may take six weeks or more to notice an improvement. After you feel better, you may be able to gradually return to higher-impact activities. You should continue to do the exercises you learned during rehabilitation even after your condition improves. Surgical treatment for patellofemoral pain syndrome is rarely recommended.
Osteoarthritis of the knee
Symptoms of knee osteoarthritis
Intermittent or steady pain
Swelling or tenderness
Stiffness when you get up from sitting or lying down
Grinding or crunching sounds
Osteoarthritis (OA) is the most common type of arthritis, affecting 27 million Americans. This disease causes the breakdown of articular cartilage, the tissue that covers and protects the ends of bones. Ligaments, menisci, and muscles may also sustain damage. Osteoarthritis can appear in any joint, but the knee is particularly vulnerable because it is a weight-bearing joint that is subject to daily wear and tear as well as sudden injury.
The wear-and-tear of aging prompts one form of OA. Yet not every elder winds up with this ailment. In fact, the average age at which knee osteoarthritis strikes has dropped from 69 to 56 since the 1990s. Why do some people get osteoarthritis while others don’t? In part, it’s genetic. If your parents or grandparents had arthritis, you are at increased risk of developing it yourself. Gender makes a difference: women have a higher risk for osteoarthritis than men. A small study comparing MRI results suggests women who have the disease also lose knee cartilage more quickly than their male counterparts.
Other factors matter, too. Quite probably, two of these factors—a rise in obesity and certain sports injuries—are helping drive down the age at which osteoarthritis occurs. According to the Arthritis Foundation, every pound gained adds four pounds of pressure to your knees. One study estimated that knee osteoarthritis in older men would drop by a fifth if those who had an obese body mass index (BMI of 30 or higher) lost enough weight to fall into the overweight body weight category (BMI 25-29.9). The same shift for older women would cut knee osteoarthritis by a third. Knee injuries, demanding physical activity, and weak muscles around the knees, particularly among women, can also raise osteoarthritis risk. For example, research shows that the physical pounding joints take during some competitive sports like soccer, football, weight lifting, and long-distance running, particularly when played at elite levels, bumps up the risk for osteoarthritis.
Cartilage is about 75% water. It compresses under the pressure of each step and resumes its original thickness when the force is released. When articular cartilage breaks down (see Figure 5), the result is pain and disability. One in three people over age 62 has some amount of osteoarthritis in one or both knees.
Figure 5: Osteoarthritis of the knee
Age, mechanical wear and tear, genetics, and biochemical factors all contribute to the gradual degeneration of the cartilage and the meniscus. In this illustration, the articular cartilage of the condyles (knobs at the lower end of the thighbone) is degraded. Tenderness and morning pain that lasts less than 30 minutes are telltale signs of this condition.
Early in the process of knee osteoarthritis, the space between your tibia and femur decreases as the cartilage wears away. Once the cartilage disappears, bone rubs on bone, causing intense pain and often the formation of bony growths known as bone spurs around the joint. For many people with osteoarthritis, pain tends to worsen as muscles tire during the day.
To diagnose your condition, the doctor will ask you about your symptoms and medical history and may suggest laboratory tests and x-rays. If the osteoarthritis has progressed far enough, x-rays may show a reduction in the joint space in the knee or the presence of bone spurs. There is no specific blood test for osteoarthritis. If your knee is suddenly swollen for no apparent reason, the doctor may remove some of the synovial fluid in the joint to check for signs of infection or arthritis. An excess amount of normal synovial fluid or synovial fluid that is thinner or less elastic than normal may be a sign of osteoarthritis, whereas synovial fluid that is opaque and deep yellow or greenish yellow may indicate inflammation, which is characteristic of rheumatoid arthritis, the destructive joint disease in which the body attacks its own tissues.
Treating osteoarthritis of the knee. So far, osteoarthritis has no cure. Although it is possible to regrow cartilage in the laboratory, implanting new cartilage and getting it to grow in an osteoarthritic knee is challenging and may depend on the amount of arthritis and its location. Like healthy plants in unhealthy soil, the implanted cartilage eventually dies.
Doctors focus on three things when treating osteoarthritis: relieving pain, protecting joints, and improving muscle tone to help stabilize joints and prevent deformity.
For pain relief, over-the-counter pain relievers, including acetaminophen or NSAIDs, can be effective. A combination of pain relievers, such as acetaminophen and ibuprofen, may bring more relief than using one of these medications alone. Do not exceed recommended dosages. Pain relievers have a variety of side effects, so it’s important to discuss your personal health risks with your doctor when considering the regular use of these medications. Occasionally, a doctor may inject a long-acting corticosteroid drug into a joint, often combined with a local anesthetic, to ease pain. However, repeated injections may speed degeneration of cartilage.
Self-help for osteoarthritis of the knee. The right kind of exercise is a crucial component of osteoarthritis treatment. It can reduce pain and also improve your balance and your ability to walk and do everyday tasks. Regular exercise is important because the muscles surrounding the knee are prone to atrophy when not used. The quadriceps is often weak, even before symptoms occur. But choose your exercise carefully. If years of running have contributed to the arthritis in your knees, more running will only aggravate the problem. It’s best to switch to an activity like bicycling or swimming that doesn’t place as much weight on the knees. Walking can be a problem because it puts full weight-bearing stress on your knees, even while working the hip muscles harder than the knees. Using weight machines, such as Cybex or Nautilus, strengthens the muscles surrounding the knees. Range-of-motion exercises help maintain joint function and relieve stiffness.
Because the knee bears the entire weight of your body, weight loss can help ease the discomfort of knee osteoarthritis.
You can also take weight off the knee by using a cane or other walking device. Annals of the Rheumatic Diseases published the first controlled trial on this topic in 2012. In the two-month trial, cane users had less pain and better knee function and could walk significantly farther in six minutes than those not using canes. In addition, well-cushioned shoes can help reduce the impact on your knees as you walk.
Surgery. Ultimately, surgery may be the best treatment for arthritic knees. The unrelenting breakdown of cartilage characteristic of the disease means that many osteoarthritis patients will eventually require knee replacement surgery. The vast majority of people who have total knee replacement surgery have osteoarthritis. While knee replacement surgery is highly successful, artificial knees have a life span of 15 to 25 years. This makes it useful to delay the need for an all-new knee until absolutely necessary.
Several surgical procedures can help delay the need for total knee replacement. One option for people with osteoarthritis and a torn meniscus is to surgically trim the meniscus. As of this writing, this treatment is being tested in a large, multicenter, randomized trial known as MeTeOR (Meniscal Tear in Osteoarthritis Research study). It compares standard physical therapy to knee cartilage surgery in these patients. Early data slated to be presented in 2013 at an American Academy of Orthopaedic Surgeons meeting suggest the surgical approach helps only a subgroup of people with osteoarthritis: those who have experienced sudden knee pain and have an MRI verifying meniscal tears, a relatively well-preserved knee joint, and locking or catching when the knee is twisted or bent too far.
Osteotomy is another option. During this procedure, the surgeon reshapes the tibia and femur to improve the knee’s alignment. The result is better knee function and less pain. You may be a good candidate for osteotomy if you are young, active, or overweight, and if your knee damage is correctable, the damage is primarily confined to one part of the knee, and the area shows no signs of inflammation.
Arthroscopic surgery to remove torn cartilage and small bone spurs (debridement) and to flush out the joint with a saline solution (lavage) is used less often today than in years past after research revealed this technique to be useful in only limited situations.
Biological resurfacing is a method sometimes used in selected cases in young people with damaged cartilage. Cartilage cells can be harvested from a patient, cloned and reproduced in a lab, and then reinserted into the patient’s knee joint. In a younger patient, the cells have a greater chance of success than in older patients. Generally, cartilage replacement works best in patients with limited areas of cartilage damage, often caused by sports or other injuries.
Hips on the ball
Watch a ballet dancer and you can appreciate the hip joint’s ability to move in almost any direction, if only the muscles are willing. The hip is a ball-and-socket joint with a remarkable range of motion. Like the knee, the hip is a network of bones, cartilage, ligaments, and muscles. People tend to think of the hip as the part of the bone they can feel on the side of the body. But the hip is actually a large region that extends to the thigh and groin. A malfunction anywhere in this large area can cause pain and decrease mobility.
Despite its large size, the hip joint is susceptible to sudden injury from a blow or a fall, as well as from normal wear and tear. In younger people, it is often a sudden injury or collision that causes hip injury, although anatomical abnormalities and athletics can also play a role. As people age, the gradual erosion of the cartilage that coats and protects the joint can cause pain and immobility. The bone-thinning disease osteoporosis can also take a gradual toll, until a fall fractures the hip. Three-quarters of these fractures occur in women. Often, hip fractures result in disability. Worse still, one in five patients die within a year from complications, according to the Centers for Disease Control and Prevention.
Many people faced with fractures or other serious hip problems will need a total hip replacement to gain pain relief and mobility. Proper treatment depends on the cause of the problem, the person’s age, and other individual factors.
Key bone structures in the hip include the ilium, the acetabulum (a deep socket in the pelvis), the thighbone (femur), and the trochanter (a protrusion on the upper part of the femur). Your hip is designed for a difficult task: supporting the full weight of your body while allowing movement in all directions. To accomplish this, the top of the femur is shaped in a smooth ball that fits snugly within the acetabulum (see Figure 6). In women, the pelvis is wider and the bones are lighter than in men, but the hip joint structure is the same. Thanks to the perfect fit, along with the slick cartilage coating the bones and the synovial fluid lubricating the space between them, the friction between the ball and socket in a healthy hip is less than that of two ice cubes rubbing together.
Figure 6: Hip anatomy
The hip is a ball-and-socket joint reinforced by a strong ring of cartilage (labrum) inside the socket (acetabulum). Supporting ligaments allow for a wide range of motion while the hips bear the full weight of the upper body.
The acetabulum socket is cushioned and deepened by a vital rim of cartilage called the labrum.
The hip joint is surrounded by a strong joint capsule made up of four ligaments, the most important of which is the iliofemoral. These tissues keep you from moving the hip to an extreme position that could dislocate the joint.
Muscles in the thigh and lower back help stabilize and move the hip. The large gluteus maximus muscles in the buttocks extend the hips when you move your leg backward or to the side. The hamstrings also extend the hip, while the hip flexors (a muscle complex that runs from the lower back to the front of the thigh) help flex the hip when you lift your leg to the front. Muscles of the groin and abdomen are also involved in hip movement.
Places in the hip where tendons, muscles, and bones meet are protected by small liquid-filled sacs called bursae.
During your examination, the doctor will ask you questions about pain and other symptoms. Be sure to describe sensations in the entire leg: a hip problem may cause pain in the front, side, or back of your hip, in the groin, and even in the knee. Mention any physical labor or sports you participate in and falls or injuries you have experienced. Even if you landed on your knees rather than your hip, you may have jolted your hips. (See “Evaluating knees,” for a list of questions your doctor may ask.)
The doctor will watch you walk to observe unevenness or changes in your gait. Hip pain or muscle weakness can change how you walk. Speak up if any portion of your stride hurts. The doctor may examine your shoes for signs of abnormal wear. He or she will observe how far you can flex your knee toward your chest and extend your leg out behind you, and how readily you can move your leg out to the side (abduction) and across your midline (adduction). As you lie on your back, the doctor will measure how far you can rotate your hip externally (letting the knee fall toward the outside of your body) and internally (letting your knee turn toward your midline). As you move or try to resist pressure applied by the doctor during different maneuvers, the doctor will assess pain, muscle strength and restrictions, and any grinding or snapping in the joint.
Along with the hip exam, the doctor will examine the position of your pelvis, compare your leg lengths, test nerve function in your legs, and check your feet and ankles for swelling that might indicate impaired circulation. He or she will also examine your spine for curvatures or conditions (such as a pinching of the sciatic nerve) that can cause hip pain.
Imaging tests will likely be ordered to help diagnose hip problems. Two possibilities are x-rays and MRI. Sometimes an iodine-based dye used to enhance the resolution of the MRI can help diagnose hip problems (see “Testing for knee and hip problems”). Called an MRI arthrogram, this imaging technique may be coupled with an injection of anesthetic into the hip (anesthetic arthrogram). By allowing the doctor to judge the effect of certain maneuvers performed before and after the anesthetic is injected, this test can help pin down the diagnosis.
Figure 7: Hip strengthening exercises
Iliotibial band stretch: With your right arm on the wall for support, cross your right foot behind your left. With both feet on the floor, slowly lean your hip toward the wall. Hold for 20 seconds. Switch sides and repeat
Side leg lifts: To strengthen the gluteal muscles that support the hip, lie on your side with legs straight. Lift one leg slowly and hold 10 to 20 inches off the floor. Hold for 10 seconds. Lower slowly and repeat until your muscles feel fatigued. Switch to the other leg.
Muscles of your thighs, abdomen, and buttocks attach at your hip joints. You might injure these muscles and nearby tendons when you exercise too much or participate in activities that you don’t do regularly or for which you lack sufficient conditioning.
Hip muscle strains
Symptoms of hip muscle strains
Symptoms of hip flexor strain:
Pain near the crease where the thigh meets the pelvis
Pain or pinching when pulling your knee to your chest
Symptoms of hamstring strain:
Pain at the back of the thigh
Swelling and sometimes bruising in the back of the thigh
Muscle spasm of the hamstring
Pain when walking or bending and straightening the leg
A popping or tearing feeling when serious injury occurs
With age, the hip muscles become prone to strains, particularly the hamstrings in the back of the thigh, the hip flexors in the front, and the adductors on the inside of the thigh. A mild strain involves overstretching the muscle; a moderate strain, mild tearing; and a severe strain, a full tear. Heavy lifting or pushing, biking (especially if your seat isn’t high enough), high kicking, martial arts, playing soccer with lots of kicking, or running with knees lifted high can all cause hip strain.
Treating hip muscle strains. When you seek medical help, your doctor will ask about your activities and how the pain began. It may hurt when the doctor pulls your knee to your chest or rotates your hip inward during the physical exam.
Initial treatment consists of rest and ice along with pain medications such as acetaminophen, ibuprofen, or naproxen. If the pain is severe, you may need crutches to take weight off the area. After swelling improves, usually in several days, you can begin gentle stretches, using heat and ice as needed. Rehabilitation after hip muscle strain involves strengthening and stretching the muscles, improving endurance, and training before returning to any physical activity.
Symptoms of tendinitis of the hip
Pain at the side of the hip when you rise from a chair or climb stairs
Hip tendinitis is inflammation of a tendon caused by microscopic tears. Tendinitis of the structures attached to the hip flexor muscles, such as the iliopsoas tendon, occurs commonly in older people whose gait has been thrown off by related problems in the spine, knees, ankles, or hips. In younger people, it develops more often in athletes, such as gymnasts and dancers, who repeatedly lift the leg while their hip is rotated out. Runners are particularly vulnerable when they train on hills and increase their mileage rapidly.
During your examination, the doctor checks for pain by pushing against your thigh as you flex your hip (moving your knee toward your chest while you sit or lie down). You will need to tell your doctor about the location of the pain and what kinds of activities seem to trigger it.
Treating tendinitis. Initially, the goal of treatment is to reduce inflammation and make you more comfortable, using ice and acetaminophen or NSAIDs. After a few days, you can try heat. During the first few days, don’t put any unnecessary pressure on the area. Sleep on your unaffected side with a pillow between your legs. Once swelling has subsided, you can gently begin to exercise the area to improve the strength and flexibility of the muscles. If you know what activity led to your tendinitis, avoid it for at least 10 days or until you are pain-free, which may mean waiting longer. When you do begin again, start at a lower intensity.
If your condition does not respond to treatment, your doctor may order additional tests to rule out a fracture or tumor.
Symptoms of hip bursitis
Symptoms of trochanteric bursitis:
Aching or burning on the outside of the upper thigh
Pain that moves down the outside of the thigh to the knee
Increasing pain when you lie on the affected side
Pain that interferes with sleep
Pain triggered by walking, climbing stairs, or getting up from sitting
Symptoms of ischial bursitis:
Dull or sharp pain in the lower buttock
Pain that increases when you sit down or lie on your back
Radiating pain in the back of the thigh
Symptoms of iliopsoas bursitis:
Pain in the front of the hip that worsens when you flex the hip
Radiating pain down the front of your thigh
Limping (if only one leg is involved) or taking smaller steps
Limited range of motion in the hip
Bursae sometimes become inflamed, creating stiffness and pain (see Figure 8). Hip bursitis is more common in women and in middle-aged and older people.
Figure 8: Bursitis
The hip has several fluid-filled sacs, called bursae, that cushion the joint. When one of these sacs becomes irritated or inflamed, the condition is known as bursitis. Inflammation of the trochanter bursa at the widest part of the hip is the most common type of bursitis in the hip. But inflammation of the iliopsoas bursa near the groin and the ischial bursa that you sit on are common, too.
Trochanteric bursitis. This painful condition can result from a single hard fall on your hip or the accumulation of minor stresses—such as small injuries, excess pressure on one hip when you walk or run (from scoliosis, other joint damage, or unequal leg lengths), carrying a shoulder bag that hits against the side of the hip, and even lying on one side of the body for an extended period (perhaps after another injury). In women and in middle-aged and older people, particularly those who exercise only sporadically, a tight iliotibial band is likely to cause pain in the hips (see “Iliotibial band syndrome”). The pain is usually located about one inch behind the trochanter (the bony bump on the side of your hip). A tight IT band can mimic the symptoms of trochanteric bursitis; in some cases, it can cause it.
Ischial bursitis. This condition occurs when the bursa under one of the ischia (the bones you sit on) becomes inflamed. As suggested by its nicknames “weaver’s bottom” and “tailor’s seat,” it can occur from prolonged sitting on a hard surface, as well as from a fall or repeated friction during bicycling or rowing.
Iliopsoas bursitis. This form of bursitis affects the protective sac that lies between the front of the hip joint and the iliopsoas muscle, one of the hip flexors. It can be associated with rheumatoid arthritis or osteoarthritis of the hip, or it may be brought on by overdoing activities that require repeated hip flexing (such as soccer, ballet, jumping hurdles, or running uphill).
Treating bursitis. During your medical exam, the doctor assesses the range of motion in your hip joint and presses on the hip bursae to check for tenderness. You may have an x-ray or MRI to help the doctor rule out conditions that sometimes cause similar symptoms, such as fracture, bone spur, arthritic joint damage, tumor, or an area of dead bone. If an infected bursa is suspected (a rare circumstance), the doctor removes some fluid from the sac for testing.
Treatment includes rest and ice along with pain relievers such as ibuprofen or naproxen. You’ll need to reduce your activity until the symptoms subside, usually in a few weeks. Physical therapy with specific stretching and strengthening exercises may be helpful. For trochanteric bursitis, therapy may involve iliotibial band stretches (see Figure 7). For iliopsoas bursitis, you may stretch and strengthen the hip flexors and rotators. Talk with your doctor or physical therapist about how to do these exercises. For ischial bursitis, you may temporarily use a cane to take pressure off the affected hip. If needed, a single corticosteroid injection with a local anesthetic typically provides permanent pain relief.
In rare cases, the bursa remains inflamed and painful even after these nonsurgical treatments. If this is the case, a doctor may surgically remove the bursa (the hip can function normally without it). This is a very effective procedure that may also be done endoscopically, on an outpatient basis.
Symptoms of labral tear
Deep, sharp pain in the groin or the front of the hip when you deeply bend your hip joint or rotate the hip
Pain that worsens during a high pivoting motion such as in basketball, tennis, or soccer
Limited range of motion
Locking or catching when pivoting or twisting
Painful clicks and pops
Symptoms such as back pain or groin pain that can seem unrelated to hip injury
The labrum is the gasket of the hip—the resilient lining of the hip socket that cushions and seals the joint. A dislocation or other injury of the hip, such as that sustained in a fall or car accident, can rip the cartilage of the labrum.
In proper position, the labrum creates a seal that helps keep the hip joint properly lubricated. Losing this seal invites cartilage damage. People who do a lot of squatting, such as plumbers, are more susceptible to labral tears. A labral tear is more common in someone born with an abnormally shallow hip socket, a condition that puts more pressure on the rim. And doctors have recognized that milder pivoting injuries can also cause labral tears (see Figure 9). Sports that require rotation of the hip, including golf and hockey, increase risk, as do running and sprinting. Almost all labral tears are linked to abnormalities of the hip bones—lumps or bumps on the ball of the femur that can tear the labrum. If surgery is recommended, these abnormalities will need to be repaired at the same time as the labral tear; otherwise the tear will recur.
Figure 9: Labral tear
The labrum is the thick cartilage that lines your hip socket. When the labrum is torn by injury or even by mild twisting movements, it can set the stage for further cartilage damage and osteoarthritis.
A labral tear may cause immediate symptoms or may not bother you, even while it sets the stage for later joint problems. An injured labrum loses some of its ability to protect and cushion the cartilage lining the socket beneath it. A roughened edge may begin to scrape against cartilage on the ball of the hip joint, leading to osteoarthritis.
To diagnose a labral tear, the doctor extends your hip fully and puts it through a range of motions to check for pain, clicking, and restricted movement. The hip may hurt when the doctor turns it inward, and it may click when the doctor pulls it to maximum extension. The findings are often not definitive, however, and confirming the diagnosis can be difficult. Standard x-ray and CT scans are not helpful because they do not reveal cartilage abnormalities, and a standard MRI does not have enough resolution to show a torn labrum. These techniques may help rule out other problems, however.
A technique in which gadolinium (a metal dye) is injected into the hip joint before an MRI is highly accurate in detecting labral problems. The most definitive way to diagnose a labral tear is by looking directly into the joint using arthroscopy. This procedure requires an experienced surgeon and sophisticated equipment.
Treating labral tear. Nonsurgical treatment of a labral tear includes pain-relief medication, physical therapy, and temporary use of crutches until symptoms subside. The tear itself will not heal or disappear, but usually your pain and other symptoms will improve. Corticosteroid injections into the hip joint, performed under x-ray or using ultrasound for guidance, can also help relieve pain and reduce inflammation.
If your condition interferes with movement or your doctor thinks it will lead to joint degeneration, you may undergo arthroscopic surgery. The surgeon confirms the diagnosis and treats the tear, usually all in the same procedure. Treatment involves either cutting out and removing the torn and frayed areas, or repairing and reattaching the torn cartilage with sutures.
Improved techniques and better surgical instruments now allow surgeons more opportunities to save the labrum, particularly in younger patients. In the case of acetabular impingement (see “When young hips go bad”), an experienced surgeon can restore the ball of the hip by shaving it into the shape of a sphere, repair the labrum, and trim the rim of the acetabulum. The goal is to improve the fit of the ball in the socket so that it can rotate more smoothly.
When young hips go bad
Doctors have discovered that the labrum is susceptible to damage when an irregularity or bump on the ball at the top of the femur or the edge of the acetabulum wears away at the labrum, causing damage.
Pain, inflammation, and disability can result. This condition, known as femoroacetabular impingement (FAI), has temporarily disabled even young, professional athletes. It is thought to contribute to early arthritis in young athletes.
While the causes of the irregularity are not clear—it may be congenital or caused by some injury—surgical repair can restore the labrum and remove the irregular lumps on the ball or in the socket of the joint to help the ball-and-socket joint function more smoothly.
Recovery after surgery depends on the extent of the repairs made. You will need crutches for at least several days. Experiencing mild to moderate pain is common. You may be able to resume some normal activities after about two weeks and begin participating in sports at about six weeks. It may be four months before you can return to activities like soccer or basketball that involve vigorous movements. Researchers have found that smokers have a significantly slower rate of healing after labral repairs than nonsmokers. A retrospective study following up on 204 active, middle-aged women and men who had arthroscopy to repair labral tears between 2001 and 2009 was reported at a 2012 meeting of the American Orthopaedic Society for Sports Medicine. Fifty-eight percent of the patients had good to excellent results. Risk for poor outcomes was higher among those who were over 40, unemployed, or obese. Further research is necessary to confirm these trends.
Calculate your risk
Researchers from the Women’s Health Initiative have developed a risk calculator for postmenopausal women over age 50 that assesses a woman’s risk of breaking a hip in the next five years. Risk is calculated based on responses to questions about 11 risk factors. The calculator is available online at hipcalculator.fhcrc.org.
Symptoms of hip fracture
Severe pain in the hip or groin
A turned-out leg that may appear shorter
Swelling, tenderness, and bruising around the hip
Inability to stand up (from either weakness or pain)
Deformed appearance to the hip
Hip too weak to lift the leg
Every year an estimated 340,000 hip fractures occur in the United States. Fortunately, the number of hip fractures have declined in people ages 65–84 since 2000, but unfortunately, they have gone up considerably for people ages 85 and older, according to data from the CDC. The decline in hip fractures among younger seniors might be due to the use of bone-preserving drugs known as bisphosphonates. And a domino effect might be occurring, where then the older seniors might be “putting off the fractures” until very late in life. In fact, the average age for hip fracture has steadily increased, from age 73 to age 79 since 1970.
For thousands of people who do suffer a hip fracture, life may never be the same again. As many as one in two are no longer able to walk without assistance—even if they were alert, healthy, and mobile beforehand. One in five hip fracture patients over age 50 die within a year of their fracture from ensuing health complications. Thus, taking steps to prevent hip fracture is extremely important. Without active effort to reduce the risk among older people, hip fractures and disability will continue to surge as life expectancy increases and people spend more time in the high-risk years.
Nine out of 10 hip fractures result from falls. Most others follow car accidents or other traumas. The risk of hip fracture is higher in someone with the bone-thinning condition called osteoporosis (see Figure 10). Nearly 10 million Americans have osteoporosis and another 34 million may have low bone density, which puts them at higher risk for developing osteoporosis. The mere impact of walking can break the hip of a person with severe osteoporosis.
Figure 10: A fragile state
Osteoporosis causes bone to become porous and fragile. Over time, calcium leaches from the bone, lowering bone density and depleting its strength. The result is bone that is vulnerable to breaks. Osteoporosis contributes to more than two million bone fractures a year. Spinal, wrist, and hip fractures are most common, with hip fractures being the most serious of all.
Three-quarters of all hip fractures occur among women. Race, ethnicity, and age affect the odds, too. White women are far more likely to suffer hip fractures than African-American or Asian women. At ages 85 and older, women and men alike are 10 to 15 times more likely to fracture a hip than people ages 60 to 65. Fracture risk is also higher for people on dialysis and remains high the first few years after a kidney transplant.
A possible hip fracture needs immediate evaluation. An x-ray is likely to show a fracture if one exists. But if it doesn’t, and your symptoms strongly suggest a fracture, an MRI may reveal a break that has not moved out of place or a fracture involving the hip socket rather than the femur.
The two most common types of hip fracture involve the femur. A femoral neck fracture occurs in the horizontal section of the femur, about one to two inches from the ball of the hip joint. An intertrochanteric fracture occurs in the femur three to four inches below the ball of the hip. Fractures of the hip socket are less common.
The severity of a hip fracture is judged by how far the bone has moved out of place. If the bone has cracked but not separated, it is described as nondisplaced. If the bone has shifted slightly, it is classed as minimally displaced. If the bone is completely detached at the break site, it is said to be displaced.
Treating hip fracture. The goal of treatment is to reconnect the broken bone and hold it in place so the hip works properly until it has time to heal—about three months. Surgery within 24 hours is usually necessary to make this repair. If you must wait for surgery, the hip may be held in traction (using weights to extend the muscles around the hip).
If you have a femoral neck fracture in which the pieces are not displaced, the orthopedic surgeon may connect the bone with surgical screws. If the bone has moved well out of place, or if you are older and not active, your surgeon may replace the head of the femur with a metal device, a procedure called a hemiarthroplasty or partial hip replacement (see “Hemiarthroplasty”). Or the surgeon may perform a total hip replacement (see “Hip replacement procedure”), if arthritis is present. If you have an intertrochanteric fracture, the doctor will stabilize the joint with screws and a device that holds the broken bone in place.
After surgery, it can take several months for the hip to heal completely. Initially, you’ll use crutches or a walker, putting weight on the leg only as permitted by your doctor. How soon you can put weight on the leg depends on the type of pinning or other device used in the repair. The goal of rehabilitation is to get you back on your feet as soon as possible. To prevent another fall, your physical therapist will work to help you develop a secure, balanced gait and will suggest other safety measures. To help prevent a second fracture, you should be evaluated for osteoporosis and treated if necessary.
Throughout life, bone is formed by cells called osteoblasts and torn down for repairs by cells known as osteoclasts. This process is called resorption. Your doctor may decide to prescribe a drug from a class of antiresorptive agents called bisphosphonates, which increase bone density by slowing the rate of bone loss. These drugs include risedronate (Actonel) and alendronate (Fosamax), both available in daily and weekly doses; ibandronate (Boniva), which comes in daily or monthly doses; and zoledronic acid (Reclast), a once-yearly treatment given intravenously. They reduce the risk of spine, wrist, and hip fractures by 40% to 50%. In 2012, an FDA review of the long-term safety of these drugs followed reports of several rare, but serious adverse effects: unusual thigh bone fractures, esophageal cancer, and weakening and crumbling bone in the jaw. At this writing, updated labeling required by the FDA notes that the optimal duration of bisphosphonate use has not yet been established. Periodic reevaluation of the need for this therapy based on individual costs and benefits is recommended, especially for patients who have taken the drugs for more than five years.
More common side effects of bisphosphonates may include esophagus and stomach irritation, causing heartburn and nausea, flu-like symptoms, fever, and muscle, bone, or joint pain.
Risk factors for hip fracture
Numerous factors can put people at risk for hip fracture.
For women and men:
A close relative with osteoporosis who broke a hip or wrist
A diet poor in calcium and vitamin D
Excessive alcohol consumption
A broken bone after age 50
General poor health
Taking medications that can make bones more fragile (such as corticosteroids, anticonvulsants, aluminum-containing antacids, and thyroid medication)
For women only:
Menopause before age 45
Dieting or exercising during the reproductive years to the point where menstrual periods ceased
Height over 5 feet, 8 inches, at age 25
Osteoarthritis of the hip
Symptoms of hip osteoarthritis
Pain radiating to your buttocks or knee
Pain in the groin or inner thigh
Pain when you pivot or rotate the hip inward
Stiffness after inactivity and first thing in the morning
Limping or other gait changes
Apparent shortness of the leg on the affected side
Difficulty with foot care
Groin pain when you get out of a chair
Difficulty getting in and out of a car
The hip joint is one of the most common sites for osteoarthritis. This condition begins with a small amount of cartilage disintegration, resulting in some local inflammation. The process continues as the cartilage erodes and bone spurs form. While there is no ironclad way to prevent this from occurring, most doctors believe that a healthy lifestyle is the best way to avoid hip osteoarthritis. In particular, maintaining a healthy weight from early adulthood on and exercising regularly to maintain muscle tone will help keep your hip joints strong.
Hip osteoarthritis is more common among the elderly and those who have had hip injuries, although some conditions, such as femoroacetabular impingement (FAI; see “When young hips go bad”), can contribute to hip arthritis at an earlier age. Obesity also places extra stress on the hips; in the Nurses’ Health Study, an ongoing study of thousands of women, those who were in the heaviest group at age 18 had five times more risk of developing severe hip osteoarthritis than those who were in the lightest group. Recreational physical activities, including running, have not been shown to raise the risk of hip osteoarthritis.
To diagnose your condition, your doctor will ask you about your symptoms and perform a physical exam. Although an x-ray will not show cartilage damage, it may reveal other changes related to osteoarthritis, including decreased joint space, bone spurs, and cysts. A blood test for inflammation helps rule out other possible causes of your symptoms.
Treating osteoarthritis of the hip. The first line of treatment for mild osteoarthritis of the hip is a combination of over-the-counter or prescription pain relievers. Using acetaminophen along with ibuprofen or another NSAID makes it possible to use a lower dose and thus minimize side effects. NSAIDs may be more effective than acetaminophen in treating osteoarthritis because they not only relieve pain but also reduce inflammation that contributes to pain, swelling, and stiffness. Steroid injections are also sometimes used to provide pain relief.
Exercise is important to help keep your hip joint limber. Water exercises are particularly suited for improving the hip’s range of motion and promoting strength and flexibility in the muscles surrounding it. Local chapters of the Arthritis Foundation may offer water and land fitness classes that fit the bill nicely (see Resources). For exercise to be effective, you must make an ongoing commitment to exercising several days a week. In studies from the Netherlands, a 12-week supervised exercise program significantly improved pain and function in people with osteoarthritis of the hip or knee. The benefits disappeared within nine months for those who did not continue to exercise, however. Talk with your doctor or physical therapist about a full program of hip-strengthening exercises.
Resting the hip when you feel pain is also important. A cane or a walking stick held in the hand opposite your bad hip can take pressure off the joint as you walk or do other activities that tend to aggravate the pain. Most people limit stair climbing and cut back on walking longer distances. When bathing, use a shower stool and hand-held nozzle to avoid standing.
Eventually, hip replacement surgery may be necessary. The vast majority of patients who undergo total hip replacement surgery have a principal diagnosis of osteoarthritis.
Testing for knee and hip problems
Sometimes a physical exam and your symptoms provide sufficient information for your doctor to make a diagnosis. But when that’s not enough, a variety of imaging techniques and laboratory tests can clarify the situation.
Medical technology has expanded doctors’ ability to create images of joint damage far beyond the simple x-ray. Each imaging technique offers something different, and the choice will depend on the type of joint damage your doctor suspects.
X-ray. A standard x-ray, the most commonly used imaging technique, gives a two-dimensional picture of the bones in your joints (see Figure 11). X-rays can show bone fractures, spurs, loose fragments, dislocation, reduced space between bones, and bone damage from arthritis. But standard x-rays don’t show cartilage, ligaments, or tendons; seeing these requires more sophisticated imaging techniques. For a standard x-ray of the knee, you may be asked to lie down or stand while a technician takes several views with your knee in different positions. For a hip x-ray, you will probably be asked to lie down. Even if only one knee or hip causes you problems, your doctor may order x-rays of both to compare the appearance of the joint and joint space.
Figure 11: Hip x-ray
This x-ray shows osteoarthritis of the hip. Compared with the visible outline of the ball-and-socket joint on the left side of the x-ray, the joint on the right has noticeably deteriorated.
CT scan. Doctors sometimes order a CT (computed tomography) scan to look for hidden fractures, bone lesions, and other structural abnormalities. A CT scan uses a rotating x-ray tube housed in a doughnut-shaped machine to take many cross-sectional x-rays of your anatomy. A computer assembles these “slices” into a three-dimensional picture. During the scan, which takes less than an hour, you lie on your back on a movable table that is raised, lowered, and moved in and out of the scanner. The equipment doesn’t touch you, and the test isn’t uncomfortable. CT is expensive, however, and involves much higher amounts of radiation than standard x-rays, but it provides an enhanced view of bone. This allows your doctor to better evaluate bone shape and diagnose some defects hidden on standard x-rays. CT does not show soft tissue.
MRI. This test does not involve radiation. Instead, MRI uses a strong magnet and radio waves to evaluate cartilage, soft tissues, and bone marrow. MRI is more expensive than CT or standard x-rays, but it’s the most accurate way to detect ligament damage, cartilage damage from arthritis, or tears in the cartilage or meniscus. A technique in which gadolinium (a metal dye) is injected into the hip joint before an MRI is highly accurate in detecting labral problems, such as labral tears. MRI is also used to evaluate a possible pelvic fracture, tumor, or osteoporosis of the hip. During the exam, which lasts about 45 minutes, you lie on a scanning table that slowly moves you through the machine. (Many centers have smaller MRI machines that can focus on specific body parts, so if you’re having your knee done you may only need to insert your knee.) For a hip exam, your feet may be taped together to keep your hips in the desired position. For a knee exam, a wedge may keep your knees at the desired angle. In some cases, the radiologist may inject a dye to obtain better images. You cannot have an MRI if you have a pacemaker, aneurysm clips, or certain other metal implants.
While imaging tests can give your doctor a good view of the damage in your knees or hips, laboratory tests are sometimes needed to determine what is causing the damage and how it might be halted.
Arthrocentesis. If you have sudden or unexplained swelling in a knee, hip, or other joint, your doctor may perform an arthrocentesis, removing a little synovial fluid for examination. Excess synovial fluid may indicate infection, crystal deposits, trauma, or inflammation. Before arthrocentesis, the skin is cleaned and an anesthetic spray or injection is used to numb the area. The doctor inserts a needle with a syringe attached into the joint space (you may hear a pop) and withdraws a fluid sample, which is sent to a laboratory for analysis. If you have pain afterward, your doctor may suggest ice and pain-relief medication. The procedure may immediately lessen pain and pressure caused by excess fluid. Knee arthrocentesis can be done in the doctor’s office. Hip arthrocentesis is performed by a radiologist, guided by fluoroscopy, a type of x-ray that shows internal structures in motion.
Optical coherence tomography
Optical coherence tomography, or OCT, is an imaging technology that obtains very clear pictures with infrared light rather than radiation. Currently approved to diagnose eye problems, OCT is being used experimentally for knee evaluation. It may lead to more accurate diagnoses of problems such as meniscal tears and cartilage defects and better decisions about which patients will benefit from surgery.
OCT delivers extremely high-resolution three-dimensional images of bones and tissue. The images are 10 to 100 times more detailed than scans produced with current imaging technologies such as CT or MRI, enabling doctors to better see subtle anatomical changes that may be causing pain and affecting mobility. The technology is particularly well suited for observing early structural changes in cartilage associated with osteoarthritis. The hope is that OCT will allow osteoarthritis to be diagnosed before cartilage begins to thin, and will then be used to monitor the effectiveness of therapeutic interventions and the progression of the disease.
OCT imaging is performed through a needle arthroscope or a surgical arthroscope. As such, it will probably be reserved mainly for cases where existing diagnostic techniques are inconclusive, or during an arthroscopic surgical procedure to evaluate the health of the existing cartilage.
Rheumatoid factor. This blood test detects an antibody present in about 70% to 80% of people with rheumatoid arthritis, a systemic autoimmune disease. The same antibody is also present in other medical conditions and some healthy people. In fact, roughly 10% of people who do not have rheumatoid arthritis test positive for rheumatoid factor.
Erythrocyte sedimentation and C-reactive protein. These blood tests are general measurements of inflammation of any kind; the higher the result, the more severe the inflammation. Most people with osteoarthritis have normal values, but those who have inflammatory conditions, such as rheumatoid arthritis, usually have elevated levels. High rates may also be an early sign of infection after knee or hip surgery. High levels of C-reactive protein over the long term also indicate an increased risk for heart disease.
Serum uric acid. The serum uric acid test measures uric acid in the blood, which can help diagnose gout, a condition caused by the accumulation of uric acid crystals in a joint.
Nonsurgical treatments for knees and hips
Whether it’s your hip or your knee that’s bothering you, your doctor is likely to recommend the least invasive treatment to alleviate pain and encourage healing before resorting to surgery. Reducing inflammation, relieving pain, protecting the joint from further damage, losing excess weight, and building strength in the muscles that support the joint can often improve joint function. The following treatments are often recommended for hip or knee pain and discomfort.
RICE—which stands for rest, ice, compression, and elevation—is a first-aid strategy for most musculoskeletal injuries, including those involving the knees and hips. It is sometimes the only treatment you need.
Exercising without stressing your hips and knees
If you like to exercise regularly but need to give your hip or knee a rest while an injury heals, here are some exercises you can do in the meantime. You can combine these exercises to create a routine lasting 30 minutes or longer:
In the Resources section you’ll find information regarding The Joint Pain Relief Workout: Healing Exercises for Your Shoulders, Hips, Knees, and Ankles, a Special Health Report from Harvard Medical School that has photographs and descriptions of many exercises that are safe for people with joint pain. Always check with your doctor first before beginning any exercise regimen.
Rest. Injuries need rest in order to heal. Rest doesn’t always mean inactivity, however. Depending on the condition, you may need to stay off a leg entirely, cut back the distance you run or walk, switch to low-impact activities, or exercise using other parts of the body. Consider using a cane to give your injury a chance to heal. It’s important to rest an injury or flare-up of pain for a few days, but long periods of inactivity can make ongoing knee and hip problems worse by decreasing flexibility and weakening the muscles that support and protect the joints.
Ice. Cold numbs pain and reduces swelling by constricting blood vessels. After surgery or injury, wrap an ice pack in a cloth and apply for 20 minutes, remove for 20 minutes, reapply for 20 minutes, and so on. To prevent frostbite, do not apply ice directly to the skin. Your source for cold can be as simple as a bag of frozen peas wrapped in a towel, but you can also buy easy-to-secure neoprene wraps with pockets for gel packs that you keep in the freezer. Most elaborate are electric “continuous-flow cold therapy” devices that deliver cold through pads shaped for different joints; your doctor or physical therapist may recommend such a device after surgery.
Ice helps knee injuries of all types. For hip injuries, cold can’t penetrate deep into the hip joint itself, but it is still effective for hip pain stemming from problems closer to the surface, such as trochanteric bursitis.
After an injury, use ice alone for 24 to 48 hours. After that, you can continue using ice, switch to heat, or alternate. Ice increases stiffness, while heat helps restore and maintain flexibility. You may find it beneficial to use warmth before stretching and other exercise, following with ice afterward to minimize swelling.
Compression. After a knee injury, gentle pressure can reduce swelling and hasten recovery time. Wrap an injured joint in an elastic bandage, taking care that the wrap isn’t so tight that the skin below the joint becomes cool or blue. Neoprene stretch knee supports provide compression and have a hole for the kneecap to prevent irritation.
Elevation. Elevating the injured area takes advantage of gravity to reduce the swelling and painful throbbing that occurs when lots of blood pools in one area. Prop your knee up on a stool with pillows to raise the height, or lie down with your knee on a pillow.
Pare off pounds
A widening girth has many health drawbacks. Among other problems, overweight and obesity places extra stress on lower body joints, raising the risk for osteoarthritis and thus paving the path toward joint replacement. An Australian study following more than 39,000 healthy adults for 15 years reported that knee or hip replacements were needed more than three times as often among those in the heaviest group (women weighing 160 pounds or more; men weighing 214 pounds or more) versus the lightest group (women weighing less than 130 pounds; men weighing less than 160 pounds).
Eating a healthy, balanced diet—one stressing plenty of vegetables, fruit, whole grains, and lean protein—watching portions, and getting sufficient exercise can help you gradually pare off pounds. (See “Lose Weight and Keep it Off” in the Resources section.) Losing extra weight has undoubted perks for your joints, as well as all-around health. A study of overweight or obese older adults who had knee osteoarthritis noted that every pound lost reduced the stress on their knees fourfold.
Even if you don’t like to exercise, if you want to save your joints, it’s important to get and keep your body at a weight that’s not too heavy for your frame. If you are already losing cartilage in your knees or hips, unless you lose weight, your joints will only continue to deteriorative. So get yourself a nutritionist. Spring for a personal trainer you like and who you feel is on your side. As you watch those pounds slip away, feel your joints thank you.
Everyone into the pool!
Exercise in the water has special benefits:
Heat is a good way to reduce pain and stiffness in your joints and relieve muscle spasms. After an injury, wait a day or two for swelling to go down before using heat. You can use a heat pack applied directly to the joint, or warm your knees and hips in a hot tub or whirlpool or with a 15- to 20-minute soak in a regular bath. Therapists recommend a warm shower or bath before exercising to relax joints and muscles. Dress warmly afterward to prolong the benefit. Heating pads are convenient, but moist heat penetrates more deeply.
To relieve muscle spasms, a physical therapist may use diathermy (deep heat), a technique that uses electromagnetic waves to deliver heat beneath the skin and to relax muscles. Electromagnetic waves cannot be used on people with pacemakers.
Cold and heat work well in combination. You may benefit from using heat early in the morning and before exercise and using cold after exercise and at the end of the day.
Ultrasound, phonophoresis, and iontophoresis
Therapeutic ultrasound uses sound waves to reach deep tissues in order to increase blood flow, relax muscle spasms, and aid healing. To do ultrasound therapy, the technician applies a gel to your skin and rubs an ultrasound wand over the area. In a technique called phonophoresis, medication (often hydrocortisone) is added to the gel and the ultrasound transducer is applied over it. Because the ultrasound encourages blood vessels to expand, this approach is thought to deliver more medication to the injured area. In a survey of orthopedic physical therapists, more than half said they would use ultrasound and phonophoresis to reduce soft-tissue inflammation (in tendinitis or bursitis, for example). The techniques were also commonly used to manage pain, heal tissue, and help muscles stretch.
Another technique, iontophoresis, uses electrical currents to speed the delivery of medication to the damaged tissue, or simply to reduce muscle spasms and related irritation. Patches similar to Band-Aids are placed on the skin, and a painless, low-level current is applied for about 10 to 15 minutes. You may feel warmth or tingling during the treatment.
Exercise is more than just a good health habit; it’s also a specific and effective treatment for many knee and hip problems. Strengthening the muscles around a damaged knee or hip can help support a joint by taking over some of its responsibilities. For example, your hips have to do less work to support your body weight if your quadriceps, gluteals, hamstrings, and abdominal muscles are stronger. A strong quadriceps can take over the shock-absorbing role usually played by the meniscus or cartilage in the knee. The proper balance of strength in the muscles can hold the joint in the most functional and least painful position. With any knee or hip problem, the first muscles to lose strength are the largest antigravity muscles, the quadriceps and gluteals, so an exercise plan for any injury is likely to focus on these.
Muscles work in pairs—one contracts while the opposing one relaxes. For example, when you straighten your knee, your quadriceps on the front of your thigh contracts, and the hamstrings on the back relax. Imbalances in the function of paired muscles can cause joint problems and invite injury. If your hamstrings are tight, your quadriceps can’t contract fully and may weaken, so exercise the quadriceps and hamstrings (the opposing muscles) equally. Flexibility exercises (to stretch and relax specific muscles) are an important part of an exercise plan to improve joint function.
Generally, choosing certain types of exercise and bypassing others is essential for compromised knees or hips. For example, you probably should avoid running and fast walking on sidewalks or pavement. If you love these activities, try them on a track or treadmill and wear well-cushioned shoes to lessen impact. Better still, consider swimming or cycling, which are easier on your joints. And do leg resistance exercises two to three times per week to strengthen supportive muscles around the knees. Strengthening muscles through these activities will dampen stresses that travel through the knee and reduce impact on the joint.
Exercising with a physical therapist
Physical therapy is often part of treatment for arthritis and other joint problems. A physical therapist individualizes your treatment program to restore or maintain your physical functioning and carries out specific instructions from your orthopedist.
First, the therapist thoroughly evaluates your pain, functional ability, strength, and endurance. A physical therapy session may involve pain-relieving treatments using ice, heat, massage, or other approaches. The physical therapist supervises you doing exercises and teaches you exercises you can do at home. There may be a pool and a variety of types of exercise equipment to use.
Gait retraining. Knee and hip problems can disrupt your normal walk by causing pain, restricting joint movement, or weakening muscles. A person’s usual pattern of standing, walking, or running may also invite joint problems if weak key muscles, poor coaching advice, or bad habits throw off the gait. It may take many years of walking with an abnormal gait before joint injury occurs. Improper running leads to pain and injury more rapidly because it involves greater force with each stride.
A physical therapist analyzes your gait and helps you learn to walk more normally. Initially, the proper gait may feel odd; you will most likely need practice and continued instruction before it becomes comfortable. The physical therapist may suggest a change in shoes or specific exercises to strengthen muscles you may be trying to avoid using.
If you have had a knee or hip replacement, gait retraining helps you relearn to stand up straight (the tendency is to lean toward your operated leg) and use both legs evenly.
Several types of medication are used for knee and hip problems, some to control pain and inflammation and others to interfere with various disease processes.
Corticosteroid injections: How many is too many?
For osteoarthritis, most experts recommend limiting corticosteroid injections to no more than once every three to four months—and a maximum of roughly four injections in any given joint. Other experts point out that since most osteoarthritis patients will eventually need joint replacement surgery, and since artificial joints have a limited life span, corticosteroid injections are an effective way to buy some time and delay surgery as long as possible.
Acetaminophen. For pain relief, acetaminophen (Tylenol, other brands) is generally the first choice because it is effective and easy on the stomach. Do not exceed the recommended dosage of acetaminophen, however, because it can damage the liver, especially in heavy drinkers who may already have some liver damage.
NSAIDs. Nonsteroidal anti-inflammatory drugs such as aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve, Anaprox), and several others may be more effective than acetaminophen, particularly during sudden flare-ups of pain, because they are superior at reducing inflammation. There are also a number of prescription NSAIDs such as nabumetone (Relafen) and oxaprozin (Daypro). Stay within recommended dosages. Regular use of NSAIDs can produce gastrointestinal bleeding and ulcers, often without warning. Combining acetaminophen with a smaller amount of an NSAID may provide equivalent pain relief with a reduction in side effects. Ask your doctor about this. Also inquire about possible risks and benefits of taking a proton-pump inhibitor such as esomeprazole (Nexium) or lansoprazole (Prevacid) to reduce the risk of gastric bleeding and ulcers.
COX-2 inhibitor. Celecoxib (Celebrex) is in a class of prescription NSAIDs known as COX-2 inhibitors, which relieve pain with less stomach irritation than traditional NSAIDs. Concerns about cardiovascular side effects mean it should be used only in cases in which a patient does not have heart disease, has tried other pain relievers without success, and is not taking blood thinners (anticoagulants such as warfarin).
Opioids. Opioid medications such as codeine and oxycodone, which have morphine-like properties, are another large class of pain-relieving drugs. Opioids work by interacting with the receptors on brain and spinal cord nerves for endogenous opioids, which are the body’s natural painkilling substances. For orthopedic problems such as knee and hip conditions, opioids may be prescribed judiciously, often for only brief periods just before and after surgery. They may also be prescribed for patients with severe pain who are not helped by, or are unable to tolerate, NSAIDs. While opioids effectively mask pain, they do not reduce inflammation and usually should not be prescribed for arthritis. Care must be taken to avoid building up a tolerance to them, which develops after just two weeks. Side effects such as dizziness can make it difficult for people to participate in physical therapy while taking these medications. Opioids can be habit-forming, too, creating physical and mental dependence, which can be a serious problem when the drugs are prescribed to treat arthritis pain. Abuse of these painkillers, which slow breathing, is responsible for an accidental death every 19 minutes, according to the Centers for Disease Control and Prevention.
Corticosteroids. Corticosteroids, such as prednisone, reduce the body’s ability to generate an inflammatory reaction. They relieve pain by reducing inflammation. Corticosteroids are credited with treating and causing knee and hip problems. When first introduced in the 1950s, corticosteroids were regarded as miracle drugs because of the dramatic effect on patients with active rheumatoid arthritis. Many were able to literally throw down their crutches. But within a few years, the devastating effects of long-term use of oral corticosteroids became apparent: bone weakening, compression fractures of the back, diabetes, increased susceptibility to infections, cataracts, hypertension, and other health problems. Most side effects occur when these drugs are taken orally, but repeated corticosteroid injections into a joint can thin cartilage and weaken ligaments. In the short term, though, corticosteroids sometimes provide quick and dramatic relief.
Over the years, people have turned to a wide variety of remedies to cope with the frustrating problem of joint pain. The choices are many, because joint pain has been around for many centuries and nearly every culture has developed medicines or therapies to treat it. Many of these remedies lack scientific support. But so long as they are not harmful, there is no reason not to use traditional or complementary therapies that seem to bring you relief. A few complementary therapies have some demonstrated effectiveness.
A word of caution
Hundreds of brand-name dietary supplements aimed at patients with osteoarthritis are on the market. In one survey, 30% of osteoarthritis patients said they have used a supplement to treat their condition. Even so, there is not yet enough scientific evidence to support the claims of most supplements. Nor is the FDA responsible for ensuring supplement safety and effectiveness, as it is with medications.
So when you are evaluating supplements, stick with information sources that are likely to be unbiased, such as the Arthritis Foundation and the American Academy of Orthopaedic Surgeons. And be sure to tell your doctor and pharmacist of any supplements you use.
This ancient Chinese technique uses slim needles to stimulate points along the body’s “energy meridians” to correct disease-causing imbalances. In the language of Western medicine, acupuncture may work by releasing endorphins, natural morphine-like chemicals in the nervous system.
Most of the studies on acupuncture are dated now, but a large 2004 study found that people with knee osteoarthritis who had acupuncture for six months reported less pain and better function than people who received sham acupuncture or participated in an arthritis education program. But a meta-analysis published in 2007 in the Annals of Internal Medicine had conflicting results. While acupuncture for osteoarthritis of the knee led to significant improvements in pain and function compared with usual care or being on a waiting list for acupuncture, it did not provide a significant advantage over a sham procedure, suggesting that some benefits might be a placebo effect. Differences in study design and size, as well as in the training and experience of practitioners, make definitive research on acupuncture difficult. If you decide to try acupuncture, find a certified acupuncturist.
The search for vitamins or other supplements to help relieve joint pain and restore cartilage has been a roller coaster ride of encouraging, then discouraging study results. The two supplements described here have shown some promise, however, they haven’t consistently demonstrated effectiveness in studies.
Glucosamine and chondroitin sulfate. Glucosamine is a substance normally found in both cartilage and synovial fluid, and chondroitin sulfate is one component of a protein that makes cartilage elastic. Research has disagreed over whether these supplements benefit people with osteoarthritis. In a multicenter randomized trial dubbed GAIT, more than 1,500 participants received one of five treatments for 24 weeks: glucosamine alone; chondroitin alone; glucosamine plus chondroitin; the pain-reliever celecoxib; or a placebo. Celecoxib relieved pain better than placebo, but the supplements, taken alone or in combination, generally failed to do better than placebo. One exception was a subgroup of participants with moderate-to-severe pain who experienced more pain relief with the glucosamine-chondroitin combination than with placebo.
Meanwhile, a 2010 study published in BMJ crunched data from 10 randomized controlled trials evaluating whether these supplements affect joint pain in the hip or knee. Six of the trials considered the effect on disease progression as well, judged by joint-space narrowing on radiological scans. The researchers reported no significant benefits for glucosamine and chondroitin compared to placebo, whether each supplement was taken alone or the two were taken in combination.
If you decide to try these supplements despite the current evidence, track your pain levels and function (such as walking ability). Discontinue the supplements after six months if they haven’t helped.
Common side effects include intestinal gas and softened stools. Chondroitin sulfate structurally resembles the anticlotting drug heparin; if you’re taking blood-thinning medication, tell your doctor and monitor your blood-clotting time. Patients with sulfa allergies should also avoid taking supplements containing chondroitin sulfate. Because glucosamine may worsen diabetes, watch blood sugar levels carefully. Glucosamine is manufactured from chitin found in the shells of crustaceans, so people with shellfish allergies may react to it.
Hyaluronic acid. This compound is found in many types of body tissue and is an important component of cartilage. Although supplements and injections containing hyaluronic acid are sometimes used for treating joint pain, solid scientific evidence for its use is lacking. A review of 89 randomized trials was published in the Archives of Internal Medicine in 2012. After analyzing data on more than 12,000 adults who received hyaluronic acid injections for knee osteoarthritis, researchers noted a small, clinically irrelevant decrease in pain and an increased risk for troubling outcomes, including hospitalization and disability.
Since the late 1970s, surgeons have been able to work inside a joint and make repairs without fully opening it up. By making small incisions (each about a quarter-inch long), a surgeon can insert a tiny video camera and miniature surgical instruments into the joint and use them to diagnose and repair abnormalities.
This approach, called arthroscopy, is less invasive than traditional surgery, and it causes less pain and fewer complications. Most arthroscopies are performed on patients between 20 and 60 years old. Good candidates for the procedure are active people in their 30s and 40s who are starting to have knee pain resulting from decades of running, skiing, basketball, or other sports. The technique has completely transformed the field of sports medicine.
The widespread use of arthroscopy for repairing knee arthritis declined after a 2002 study found that arthroscopy was no better than placebo surgery. These findings have largely been bolstered by subsequent research, including a 2008 review of three randomized, controlled trials that compared arthroscopic surgery for knee osteoarthritis to placebo surgery or other non-surgical interventions. Only one of the three studies reported benefits for arthroscopy at the five-year follow up. This studied compared arthroscopy to a technique called lavage, which uses sterile saline to flush away debris at the joint that might affect knee function rather than removing it surgically. There were no differences in outcomes between surgery and non-surgical techniques in the other two studies.
However, early data from a large, multicenter, randomized trial called MeTeOR comparing standard physical therapy to arthroscopic surgery does suggest the surgery helps a subgroup of people with osteoarthritis: those who have experienced sudden knee pain and have an MRI verifying meniscal tears, a relatively well-preserved knee joint, and locking or catching when the knee is twisted or bent too far.
Arthroscopy may be performed under general, regional, or local anesthesia. Arthroscopy is used less frequently in the hip, but is sometimes used to diagnose the cause of hip pain. If the surgeon finds a labral tear or loose pieces of bone (from a traumatic injury, for example) or cartilage during the arthroscopy, he or she can remove them during the procedure.
Recovery from arthroscopic surgery is relatively quick. You gradually get back to normal day-to-day living during the first week. In the second week, you can return to work if your job is not physically taxing. In the third week, you can begin to do light exercise. Physical therapy is not usually needed.
Uses for arthroscopy
SPECIAL SECTION: Knee and hip replacement
About 327,000 total hip replacements and 676,000 total knee replacements are performed annually in the United States. By the year 2030, the number of total hip replacements is projected to increase to 572,000 per year. The number of total knee replacements is projected to increase to an astounding 3.48 million procedures per year. Newer procedures including knee and hip resurfacing are also becoming available.
Certainly, knee and hip replacements work well for many people. More than 80% of total knee replacement patients say they’re satisfied with the result. And according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases, hip replacement is one of the most successful orthopedic surgeries performed. Still, you need to have realistic expectations about what joint replacement surgery can and cannot do. While a new hip or knee should help you in normal activities for your age, it won’t enable you to run marathons, ski on moguls, or do more than you could before you became disabled. And joint replacement doesn’t guarantee that you will be able to move or use the joint normally. Particularly at first, you will need to limit your range of motion to avoid dislocating the new joint. Some patients find the recovery period painful. Still, patients who are willing and able to participate in physical therapy can experience great improvement in function. The major consistent benefit is substantial relief from pain—after you’ve healed from the surgery. Full recovery takes about three months.
Like a pair of shoes, an artificial joint has a limited life span. The more demand your activities place on the new joint, the quicker it will wear out. With normal activity, most last 15 to 20 years. If you do regular high-impact exercise, your implant won’t last as long. If possible, people under 60 are encouraged to delay the procedure because it is more likely that they will need later surgery to replace the implant—particularly if they are extremely active or overweight. Surgery to replace an implant, called revision surgery, is more difficult because there is less bone to work with after removing the first implant.
Problems with artificial joints occasionally occur. In 2008, for example, the manufacturer of a metal hip socket known as the Durom Cup suspended sales after surgeons reported patients experiencing pain following the implantation of this device. Some patients needed repeat surgery to replace it. Ceramic-on-ceramic hip replacements cause squeaking in some patients and have, rarely, been known to shatter under heavy pressure, depositing a significant amount of debris that must be removed surgically when such failures occur.
Decisions to make
Work with your doctor to decide whether replacing your knee or hip joint is a good solution for you. Once you have answered that question, you’ll need to make other decisions, including who will do the procedure, whether you might benefit from waiting longer to have it done or if you should schedule it soon, where to have it done, what type of implant to choose, whether to replace one or two joints, and whether to do them both at once or one at a time.
Do you need a new joint?
When is it time for a joint replacement? Joint replacement is always an elective procedure. A doctor may recommend it, but you must weigh the benefits and risks and come to your own decision about whether, or when, to undergo this major surgery. Although your age is an important factor, the decision to have a joint replacement is based on your disability—how much pain you’re in and how much your joint problems limit your activities. It may be time to consider knee or hip replacement if one or more of the following statements apply to you.
you are unable to complete normal daily tasks without help.
you have significant pain daily.
pain keeps you awake at night despite the use of medications.
nonsurgical approaches—such as medications, the use of a cane, and diligent physical therapy—have not relieved your pain.
less complicated surgical procedures are unlikely to help.
pain keeps you from walking or bending over.
pain doesn’t stop when you rest.
you can’t bend or straighten your knee, or your hip is so stiff that you can’t lift your leg.
you have osteoarthritis and feel the disease is wearing you down physically, emotionally, and mentally.
you are suffering severe side effects from the medications for your joint symptoms.
x-rays show advanced arthritis or other damage.
Is it possible to wait too long? Yes, according to a study by Canadian researchers that found that waiting until joint problems have severely limited your function may lessen the benefit you get from knee or hip replacement. Two years after surgery, people who had waited longer had less pain relief and were five times as likely to need assistance with basic self-care activities. Taking into account the condition of your joints, your age, and your overall health, you and your doctor need to strike a balance between operating too soon (increasing the chance that the replacement joint will wear out) and waiting too long (meaning you will get less benefit from the procedure).
According to the American Academy of Orthopaedic Surgeons, the average age for partial or total hip replacement was 68 in 2010; for knee reconstruction or replacement it was 66. The average age for total knee replacement is 70; for total hip replacement it’s 66. If you are younger than 50 years old, your doctor may recommend that you wait a few years before having joint replacement surgery.
Some people are not good candidates. A surgeon is unlikely to offer you joint replacement if you have any of the following problems:
systemic infection or infection in the damaged knee or hip
leg circulation so poor that it will interfere with healing
severely damaged or nonworking knee muscles or ligaments
damaged nerves in the legs
neuromuscular disease such as multiple sclerosis, Parkinson’s disease, or stroke
allergy to metal or plastic
medical illness that makes any major surgery risky.
As you make the decision, bear in mind that joint replacement is a major surgery and has a small but real risk of serious complications such as infection, blood clot, and heart attack.
Selecting your health care team
Joint replacement is complex surgery, and finding the right surgeon and hospital can make a big difference in your outcome. In general, you’re likely to have a better result and fewer complications if your surgeon performs the operation frequently (at least 100 times per year) and operates in a hospital where replacements are commonplace. Don’t be surprised if this rules out the most convenient hospital.
Your orthopedist, rheumatologist, primary care physician, or a friend who has undergone successful joint replacement may recommend a surgeon. Keep in mind that your insurer may restrict you to certain specialists or require a larger co-payment if you go outside your plan.
When you meet for an initial consultation, the surgeon reassesses your condition and works with you to recommend the most appropriate treatment. If it’s clear that joint replacement is a good choice, the questions below can help you decide whether a particular surgeon is right for you:
Are you board-certified in orthopedic surgery?
Are you fellowship trained?
How often do you perform this surgery?
What kind of results would you expect for someone in my condition?
May I speak with any of your patients who have had this surgery?
What complications occur most frequently, and how do you deal with them?
Do you usually work with a particular physical therapist or rehabilitation center?
Much of your experience in the hospital and afterward will center on physical therapy, so it is worth your while to investigate this ahead of time. Look for a physical therapist who is used to working with joint replacement patients. A good physical therapist or rehabilitation center individualizes your rehab program in consultation with your doctor, finds ways you can gain muscle strength even while joint damage limits your activity, helps keep you going even through some discomfort, and helps you reach your goals (whether just walking comfortably or returning to a favorite sport).
Type of implant
The implant design—there are dozens of them—will depend on your weight, bone quality, age, occupation, and activity level, as well as the surgeon’s experience with a particular model or brand. While some designs have been around for decades and others are new, newer is not necessarily better. One crucial question is how long it will last: it takes years to determine whether a new model will last as long as those with a long-term track record. Some designs that initially seemed promising have developed problems after several years.
The components of an artificial knee joint are made from some combination of hard polished metal, hard ceramic, and tough, slick plastic. Hip implants are also made of these materials or a combination of them. All materials that are used to construct artificial joints need to following criteria:
They must function without provoking a local or systemic immune response.
They must be able to resist wear and corrosion and retain their strength and shape.
They must mechanically duplicate the joint they are replacing. For example, they must be strong enough to withstand weight-bearing loads and flexible enough to bear stress without breaking, while allowing smooth movement.
Each of the following materials has advantages and disadvantages.
Polyethylene. The plastic parts of an artificial joint are usually ultra-high-density polyethylene. The major drawback to polyethylene has been wear—tiny pieces of the plastic flake off, provoking the production of cytokines, enzymes, and other factors that weaken bone tissue. As a result, the implant pulls away from the bone and has to be replaced. Manufacturers modified the carbon bonds in the plastic to make “cross-linked” polyethylene, which is believed to be more wear-resistant. Cross-linked polyethylene is now the most popular bearing surface for total hip replacements, and improvements to the material continue to be made.
Ceramic-on-ceramic. The use of very hard ceramic material in place of some metal parts is another option. Ceramic parts can be used for both knee and hip replacement. The rate of bone deterioration associated with wear is significantly lower for ceramic implants compared with metal-polyethylene implants. However, rare failure of ceramic-on-ceramic hip implants has occurred, causing the ceramic implant to shatter and scatter debris that must be removed surgically. “Squeaking” has also been reported as a clinical problem. One study found that 7% of ceramic-on-ceramic total hip replacements were associated with an audible squeak. Thus far, the squeaking has not been associated with any clinical symptoms. And squeaking hips appear to be properly aligned and indistinguishable from silent hips on x-rays and CT scans.
Cemented or cementless? You and your surgeon will have a choice of using an implant that is cemented in place or one that is designed to stay put without cement. Cemented implants use acrylic cement to quickly establish a solid attachment, allowing you to get back on your feet more quickly—almost immediately after surgery. Cemented joint replacements have been used successfully for many years and may last more than 20 years. A successful cemented joint replacement has a stable boundary between the implant and the cement and a durable mechanical connection between the cement and the bone. Over time the cement sometimes cracks or wears out, however, loosening the connection between the implant and adjacent bone. If that occurs, you may feel pain as the implant rubs against the bone and wears it away. Eventually, you’ll need revision surgery. Loosening is more likely to occur in patients who are very active or very heavy. For this reason, cemented joint replacements are more commonly recommended for patients who are older, have conditions such as rheumatoid arthritis, or are younger but have compromised health or poor bone quality and density.
Cementless implants are now more common than cemented replacement parts. Their surfaces are semiporous, allowing bone to grow into the implant and form a solid attachment. Despite early hopes that cementless implants would be more durable than cemented implants, a 2006 review found that the longevity of cementless models is no greater than that of cemented ones. Although cementless implants are held in place with surgical screws or pegs, they are not as secure as cemented models until bone healing occurs, so your doctor may not allow you to put full weight on the leg for six weeks.
In evaluating cementless knee prostheses, doctors have found that better attachment to the bone occurs with the femur than with the kneecap or lower leg. Accordingly, some doctors use a cementless attachment to the femur and cement the other portions of the implant, an approach called hybrid or mixed total knee replacement.
You are more likely to be offered a cementless implant if you are younger and more active. Younger bone is stronger and more readily grows into the implant, creating better fixation of the implant. Of course, you should discuss your options for implant attachment with your surgeon.
Quelling infection and extending implant lifespan. Efforts are under way to decrease the rate of complications like infections, extend the life of implants, and reduce the need for revision surgery. Researchers are currently working on ways to put drugs—specifically, antibiotics—directly in the prostheses. Oral or intravenous antibiotics are routinely given to patients shortly before and after joint replacement surgery (see “Infection”). Still, serious infections can occur in the nooks and crannies of the artificial joints, where bacteria can collect. There are no blood vessels in the artificial joint, so the body’s immune cells can’t reach the infection to fight it off. These antibiotic-containing implants will be very expensive and might be best suited for those at highest risk for infection. That would include people who are obese, have diabetes, or are taking medications that compromise their immune systems.
Breakdown of the bone supporting an implant loosens it, often prompting a need for revision surgery. Some new evidence suggests bisphosphonates, drugs used to prevent bone loss, may help extend the lifespan of total knee or hip implants by blocking bone resorption. Further research is necessary to confirm this.
Two at once?
If you have severe damage and pain in both knees or hips but are otherwise in good health, you may want to consider replacing both joints during a single surgery (simultaneous replacement) as opposed to two separate operations several months apart (staged replacement). The decision requires careful discussion with your doctor and physical therapist.
The benefits of a simultaneous approach are a single anesthesia, shorter total hospitalization, and one prolonged rehabilitation that lets you resume normal activities sooner than two separate ones. Having two separate operations reduces the frequency of some complications, such as infection and needing a second surgery to fix problems. Replacing both knees at once is a good option if the condition of your joints is so poor that replacing only one joint would still leave you unable to function during physical therapy, thereby slowing your recovery. To do well in rehabilitation after simultaneous surgery, however, you need enough arm strength to cope while you can’t stand on either leg.
A possible complication of simultaneous replacement is a slightly increased risk of blood clots or another life-threatening problem like a heart attack. In analyzing thousands of knee replacements, Mayo Clinic researchers found that patients who have simultaneous knee replacement are more than twice as likely to develop dangerous blood clots or die within 30 days as patients who have single-knee surgery, although such complications are rare. In fact, having blood clots develop in simultaneous knee surgery only occurs twice in every one hundred surgeries.
Simultaneous replacement is not for everyone. It is not recommended for patients with underlying cardiovascular disease because large fluid shifts occur due to blood loss and replacement during the procedure. People over 80 and those with cardiovascular or lung disease are usually offered staged procedures. If you have any significant medical risks, you are probably better off having two separate operations.
Because you spend less time in the hospital, simultaneous joint replacement costs somewhat less than staged procedures. However, as long as replacement of both joints is medically necessary, Medicare and most private insurers cover either schedule.
Knee replacement options
Your surgeon may discuss some of the following additional options with you.
Fixed-bearing versus rotating knee platform. In a fixed-bearing knee prosthesis—the most common type—the tibial component of the prosthesis is topped with a flat metal piece that securely holds a polyethylene insert. When the knee is in motion, the femoral component glides across the polyethylene. In a rotating platform knee prosthesis, the polyethylene insert can rotate slightly, theoretically lessening stress and wear on the implant and improving movement.
According to some experts, rotating knee prostheses slightly improve on the knee range of motion offered by fixed-bearing prostheses, but have a slightly greater risk of complications. Two 2012 studies published in the Journal of Bone and Joint Surgery demonstrated that rotating-platform knee implants deliver durability and good to excellent results in terms of pain and range of motion after more than ten years of follow-up. Also reported in that journal in 2012 was a randomized trial of 240 knee replacement patients. The researchers found neither style of implant bested the other at the two-year and five-year marks in scores of knee range of motion, function, and stair-climbing. Usually, total knee replacement revision surgery requires a more constrained prosthesis with more supportive metal stems that extend into the femoral and tibial canals.
Gender-specific knees. Knee implants used to come in a limited variety of shapes and sizes. Now there are implants that are specifically designed for a woman’s anatomy, known as gender-specific knees. However, in a study that followed 85 women with knee replacements for two years after surgery, the gender-specific knees scored about the same as standard knee replacements in terms of range of knee motion and patient satisfaction.
Partial knee replacement (“mini-knee”). If your knee damage is limited to one of the bumps (condyles) on the end of your femur, you may benefit from a partial (unicompartmental) replacement that leaves the rest of the joint intact. This technology has been around for decades, but became more popular once surgeons were able to install the partial implant through a small incision (about three inches rather than eight) with minimal impact on muscles and ligaments—a surgery nicknamed the “mini-knee.”
The potential advantages are clear: less blood loss, shorter hospitalization, and quicker recovery. However, a unicompartmental replacement lasts only about 10 years, compared with 15 to 20 years for a total knee replacement. They aren’t well suited for people who are very bowlegged or knock-kneed. You may be offered this option only if damage is limited to one portion of the knee, if the damage results from a traumatic injury rather than arthritis, if your ligaments are intact, and if your knee still contains a fair amount of healthy cartilage. The ideal patient for this surgery is an older, thinner person rather than a younger, more active one. It may be suggested to buy time before total knee replacement in someone young and active, however.
Minimally invasive knee surgery. Minimally invasive knee surgery accomplishes the same goal as traditional knee replacement, using the same types of artificial knee implants as those used in traditional procedures, but through much smaller incisions. Despite the name, it is still major surgery. The size of the incision depends on the person’s size (bigger knees mean bigger incisions). On average, the incision for minimally invasive surgery is four to six inches, compared with an eight- or 10-inch incision with traditional knee replacement. Some minimally invasive techniques require small incisions to be made in the quadriceps muscle, while “quadriceps-sparing” techniques protect the quadriceps tendon and muscle. The results from several studies comparing minimally invasive surgery to traditional knee replacement have shown some benefits, including less blood loss, shorter hospital stay, and better range of motion. However, other studies show a higher complication rate with minimally invasive surgery, including less precise placement of knee implants.
The average hospital stay following total knee or hip replacement is three days. Compare this to the 1990s, when people having hip replacements averaged nine days in the hospital.
Patellar resurfacing. In some knee replacements, the kneecap is unaltered, and the artificial implant is shaped to glide easily beneath it. But in another approach, called patellar resurfacing, the surgeon attaches a separate piece to the back of the kneecap to fit smoothly with the implant, resurfacing the patella. Studies of patellar resurfacing have offered varying results: some find it reduces long-term pain, and others find it leads to more complications and a higher failure rate. A meta-analysis of 1,223 knee replacements suggested that patellar resurfacing may modestly reduce the risk of revision surgery and pain at the front of the knee. Some surgeons resurface the patella in most knee replacements; others try to avoid this step unless special circumstances warrant it. Patellar resurfacing may be a better option for younger patients, in whom the results tend to be more predictable.
Hip replacement options
Your surgeon may discuss some of the following options with you.
Hip resurfacing. Hip resurfacing is an alternative to traditional hip replacement and is sometimes used in younger patients to delay the need for total hip replacement. This system of metal-on-metal caps and socket linings was approved by the FDA in 2006. Instead of removing the head of the femur and replacing it with an artificial ball, the surgeon reshapes the head and caps it with a cobalt-chromium prosthetic that fits into a metal lining in the socket.
Hip resurfacing is an option for a young and active person. Preserving the top of the femur makes it easier to do subsequent surgery, which becomes more likely in people who will use implants for more than 20 years. Persons with severe bone loss from osteoporosis or other causes are not good candidates for this procedure.
Questions remain about the relative benefits and risks of hip resurfacing. A randomized, single-center British trial comparing hip resurfacing arthroscopy to total hip arthroscopy in 126 patients with severe arthritis found similar hip function in both groups at one year. Larger studies of longer duration must be done to gain more complete answers, however, because the procedure has not been studied as extensively or for as long as hip replacement. Complications appear to be more common among women. Studies suggest that hip resurfacing offers the best benefit-to-risk ratio for men under 60 who need a total hip replacement and would like to remain active. There are also some concerns about the long-term consequences of tiny metal particles released into the bloodstream with the metal-on-metal design (see “Metal on metal: Gone by the wayside?”).
Metal-on-metal: Gone by the wayside?
Metal-on-metal implants have been in use since the 1960s. The metal parts of an artificial joint are titanium-based or a cobalt/chromium-based alloy. However, in 2012, the FDA released results from a study that looked at 131 previously published studies on metal-on-metal hip implants and resurfacing. The expert advisory panel found that people who have gotten metal-on-metal hip prostheses, particularly women, may have been exposed to toxic metal ions and that the metal implants have an increased risk of device failure. The main concern with the devises’ potential to release metal ions into the bloodstream is that the tiny charged particles can provoke reactions that lead to the breakdown of bone. The implant may loosen as a result, requiring revision surgery. The systemic effects of metal ions in the bloodstream are currently unknown, but women of childbearing age are advised to avoid metal-on-metal implants because their effects on a fetus are also unknown. The implants are also more likely to fail in women and people who are overweight.
According to information released by the FDA, nearly 16,800 adverse events associated with metal-on-metal hip implants were reported in the United States from 2000 through 2011, including 12,137 during 2011 alone.
Minimally invasive hip replacement surgery. Hip replacement usually involves a 10- to 12-inch incision on the side of the hip. Minimally invasive hip replacement surgery may be performed through a three- to six-inch incision, which is usually placed over the outside of the hip. A second technique requires two incisions: a two- to three-inch incision through the groin to place the socket, and a one- to two-inch incision through the buttock to place the stem. The potential benefits of minimally invasive hip surgery are less muscle damage, blood loss, and postoperative pain; a shorter hospital stay; faster rehabilitation; and a smaller scar. Thus far, there is no clear evidence that minimally invasive hip replacement is safer or more effective than traditional hip replacement surgery. Minimally invasive hip replacement is a technically demanding procedure, so a skilled and experienced surgeon is of the utmost importance. Even with a skilled surgeon, however, it is still too early to fully understand the long-term risks and benefits of minimally invasive hip replacement.
Hemiarthroplasty. Hemiarthroplasty is a partial hip replacement. It involves replacing the neck and head of the femur, while leaving the acetabulum intact. Hemiarthroplasty is most often used for hip fractures in which the neck of the femur has fractured. It may also be used in patients with osteonecrosis, in which the bones lose their blood supply, or in selected patients born with a dislocation of the hip.
Personal story: Angela Lansbury
It was during the ninth season of the TV series Murder, She Wrote that actor Angela Lansbury started to feel severe pain in her hip. “It was hard to walk without limping,” she said, “At that point, I knew if I was going to continue shooting the series, I had to do it.” She had her first joint replacement surgery at age 69 in 1994 at St. John’s Hospital Medical Center in Santa Monica, the day after shooting ended for the season. Over the next 14 years, she underwent replacements of the other hip and both knees.
Although many people know Lansbury as television detective Jessica Fletcher, it was her earlier dancing and acting career on Broadway that had taken the heaviest toll on her joints. Acting and dancing is physically demanding, she said, but “Broadway was the real test. I actually didn’t start musicals until I was 40, although I had been dancing at the lots at MGM, moving and dancing all my life.” Her lead role in the Broadway musical Mame was the most demanding physical role of all. “It was eight performances a week for two and a half years,” she said. The dance movements put stress on her knees and took a toll on her hips.
Years went by before the pounding on her joints began to cause significant pain. “I had pain lying in bed at night, and going up and down stairs. It was an ongoing ache.” After 40 years of acting and dancing her way across stage and screen, she realized the time for a hip replacement was at hand.
Her first hip surgery went well and she recovered primarily at home. “There was a certain amount of pain involved,” she said. For the later joint replacements, the postoperative pain was somewhat lessened by improved pain medications, she said. Immediately after surgery, like most patients, she needed the stronger opiate pain relievers. But after a couple of weeks she was down to taking the over-the-counter pain reliever acetaminophen to ease the pain during sessions with her physical therapist. The joint replacement procedures were successful and without complications, with the exception of a small blood clot in her leg after her first knee surgery, relieved by the blood-thinning drug warfarin (Coumadin).
She gives this advice to someone contemplating joint replacement surgery: choose a surgeon who has performed the operation many times and is doing it continuously. “It’s terribly important the surgeon you choose must be doing it on a regular basis,” she said. Although Lansbury has replaced both knees and both hips, she said she decided against having two done at once based on her doctor’s advice that “one helps the other.” That means that the unoperated knee or hip helps support the body while the other heals (see “Two at once?”).
And Lansbury has stayed active, appearing in A Little Night Music on Broadway in 2009–2010, and most recently in a film called Mr. Popper’s Penguins (2011). Neither her age, 87, nor her two replacement knees and two replacement hips, are slowing her down.
Planning your surgery
You’ll schedule your joint replacement surgery several weeks or even months in advance. In the weeks before surgery, you will be asked many questions about your medical history and insurance coverage. Be prepared to discuss your medical conditions and all previous operations; medications you take regularly; allergies to drugs or anesthesia; and your insurance coverage.
During the weeks preceding the surgery, your health care team will advise you on steps you can take to help ensure a successful outcome. This may involve taking oral antibiotics as directed before your surgery and complying with your doctor’s recommendations following surgery. Losing extra pounds helps by taking a load off your knees and hips. Plus, excess weight can lead to postsurgical complications. If you smoke, quit or at least cut down. Smoking affects blood flow and inhibits bone healing and growth, slowing recovery. If you drink alcohol, abstain for at least 48 hours before surgery.
On the day you’re admitted for surgery, you will follow a standard procedure at your hospital, which will include meeting with the anesthesiologist. Once you’re ready for the operation, the anesthesiologist will insert a tube into either a vein or your back, depending on the type of anesthesia to be used. A catheter is inserted into your bladder to remove urine during the surgery.
Knee replacement procedure
For this operation, you are positioned on your back. The orthopedic surgeon makes a cut of about eight to 10 inches over your knee. The incision is about half this size for minimally invasive surgery. Moving the kneecap out of the way and taking care to do minimal damage to the muscles and ligaments, the surgeon makes flat cuts to remove damaged sections from the top of the tibia and the end of the femur and to carefully contour the bone to fit the implant. Precision guides ensure that the bone is shaped correctly to fit the implant, an innovation that makes knee replacement far more accurate and successful today than it was in the 1970s.
Sign on the dotted knee
In rare instances, doctors perform surgery on the wrong part of the body. An insurance study showed that this happened about 20 times a year in the United States from 1985 through 1995. The two most common mistakes are operating on the wrong leg and operating on the wrong part of the spine.
To lower the chances of such an error, the American Academy of Orthopaedic Surgeons has a “sign your site” protocol: surgeons are supposed to write their initials in indelible ink on the operative site as the patient watches.
So if you’re having surgery, check that your surgeon has made his or her mark. In the unlikely event that it’s not there, raise the issue with your surgeon or a nurse.
The surgeon then puts trial implants in place and tests to make sure that the knee will straighten and bend without wobbling; it takes great surgical skill to properly balance the ligaments and tendons to work with the implant. The surgeon then attaches the implant components to the femur and tibia with cement or screws (see Figure 12). If your patella will be resurfaced, the surgeon also attaches a small oval-shaped plastic piece to the back. After the surgeon finishes your knee replacement, he or she will stitch your incisions closed. The total surgical time for a knee replacement procedure is about one to two hours, though you will be in the operating room for longer than that while the surgical team preps you for surgery.
Figure 12: Total knee replacement surgery
The surgeon first cuts away thin slices of bone with damaged cartilage from the end of the femur and the top of the tibia, making sure that the bones are cut to precisely fit the shape of the replacement pieces. The artificial joint is attached to the bones with cement or screws. A small plastic piece goes on the back of the kneecap (patella) to ride smoothly over the other parts of the artificial joint when you bend your knee.
Hip replacement procedure
For this operation, you will be placed on your side. Pillows will help you stay in position during the operation. The surgeon makes a cut of about 10 to 12 inches along your hip and separates your thighbone from the hip socket. The incision for minimally invasive surgery is smaller. Using a surgical saw, the surgeon removes the damaged ball at the top of your thighbone; this is measured so a perfectly sized implant can be created from components available in the operating room. The surgeon tunnels down into the femur to create a space for the stem of the implant. After evaluating the quality of bone tissue in your femur, the surgeon decides whether to cement the implant in place. On the socket side of the joint, the surgeon shaves away damaged bone and cartilage and shapes the surface of the bone to hold the socket portion of the implant.
After the implant components are prepared, the surgeon secures them in place using cement or screws, or by forcibly press-fitting them in. The surgeon then fits the new ball and socket together and stitches the incision closed (see Figure 13). Total hip replacement takes about one-and-a-half to two-and-a-half hours, plus prep time.
Figure 13 Total hip replacement surgery
When rough and damaged cartilage prevents the bones of the hip from moving smoothly, an orthopedic surgeon can install an artificial joint with two parts. The head of the femur is replaced with an artificial ball with a long stem that fits down inside the femur bone. An artificial cup, called the acetabular cup, fits inside the hip socket. Cement may be applied, depending on which type of artificial joint is used. The two pieces fit smoothly together to restore comfortable ball-in-socket movement.
Recovery in the hospital
Once you recover from the anesthesia in the recovery room, you’re moved to a regular room. When you wake up, you’ll find several tubes extending from your body—a drain for the surgical area, a catheter to remove urine, and an intravenous line (IV) for medications. You will also have elastic stockings or compression devices on your legs to help prevent blood clots. After hip replacement, your operated leg is suspended by a sling or held in place with a special abduction pillow to keep the hip from dislocating (the ball slipping out of the socket). Postoperative recovery will vary depending on your health and age. Many doctors now allow immediate weight bearing on crutches or walker as needed. Most patients can walk without these aids after four to six weeks.
Pain control. If you had an anesthesia line in your back, it may be left in place for a day or two to administer medication to keep your lower body pain-free. Otherwise you initially receive pain medication through an IV. If your doctor has recommended patient-controlled anesthesia, you push a button to administer pain-killing drugs into your IV as you need them; the machine is programmed so you cannot use too much medication. After a while, you switch to oral painkillers. Don’t hesitate to use the medications. Pain is easier to control before it becomes intolerable. Taking medication 30 to 60 minutes before physical therapy helps you perform the exercises. In addition, the medication can help relieve pain and swelling, particularly after activity.
Breathing. After surgery, small airways in the lungs can collapse and create an ideal environment for pneumonia to develop. To keep your lungs clear, the nurse will instruct you to cough several times an hour and to perform deep breathing exercises. You may be given a breathing exerciser called an incentive spirometer that lets you see how deeply you are breathing and challenges you to expand your lungs fully.
Blood clot prevention. One potential postsurgical danger is the formation of a blood clot, usually in the lower leg or thigh. Called a deep vein thrombosis (DVT), the clot can break off and travel to the lung, lodging there and blocking off your breathing (pulmonary embolism). To help prevent blood clots, your doctor may place compression devices around your legs and feet. These devices are hooked to a machine that regularly fills them with air to squeeze your calves, forcing blood up your legs to mimic the action that your muscles would provide if you were moving around. Elastic stockings (thromboembolism deterrent, or TED, stockings) worn on both legs keep pressure on your calf muscles (and thereby your legs) to enhance blood flow. Your doctor is likely to prescribe injections of a blood-thinning medication such as heparin soon after surgery, and then switch you to an oral anticoagulant such as warfarin (Coumadin) to be taken at home for up to several weeks after surgery.
Another option for reducing the risk for blood clots is one of the newer anticoagulant drugs known as factor Xa inhibitors, such as rivaroxaban (Xarelto), which received FDA approval in 2011. Three years previously, results of a large study published in the New England Journal of Medicine found that rivaroxaban might be particularly effective at preventing blood clots after total knee replacement and total hip replacement surgery, possibly because the drug targets and inhibits clotting factors that are active after major orthopedic surgery. A 2012 analysis of 22 randomized trials compared several factor Xa inhibitors to heparin after joint replacement. The researchers concluded that use of these drugs would result in four fewer blood clots per 1,000 patients and two additional major bleeding events, though this problem occurred only among patients receiving higher doses of the medication. Evidence from eight trials also suggests that taking these drugs after surgery for 21 or more days decreases the risk for blood clots, though it increases the risk for minor bleeding, compared to standard regimens of seven to 10 days.
Machines and medications aren’t the only way to avoid blood clots after joint surgery. You can help prevent clots by moving around as much as you are allowed. While in bed you can increase blood flow by circling your ankles or alternately flexing and pointing your feet. Report any symptoms of a possible leg clot. These include: increasing swelling, pain, tenderness, or redness in your calf. A clot that has reached the lung can cause shortness of breath or chest pain that comes on suddenly with coughing; if this happens, notify your doctor immediately.
Infection control. To prevent infection, patients undergoing joint replacement are routinely given antibiotics shortly before surgery and for 24 hours afterward. It’s important to follow your nurse’s instructions about cleansing and bandaging your incision. Notify your health professional if you notice these signs of infection: redness, swelling, pain, tenderness, fever, and increasing or odorous drainage. An infection around your incision can usually be treated with antibiotics and scrupulous cleansing and dressing of the wound. In some cases, the surgeon may have to reopen the incision to remove infected tissue.
Steps to restore mobility. Your rehabilitation begins immediately. Grasp the overhead bar to shift around in bed and relieve pressure on your skin. Perform exercises as prescribed by your physical therapist.
Your knee may be placed in a continuous passive motion (CPM) machine to bend and straighten it by a programmed (and gradually increasing) amount, or physical therapy twice a day without CPM may be recommended. No evidence favors using the machine rather than actively performing knee exercises under the guidance of a physical therapist. If CPM is used, remember that the device supplements but can’t replace your participation in physical therapy.
By the day after surgery, a nurse or physical therapist will help you get out of bed and use crutches or a walker to move to a nearby chair. If you had hip replacement, an abduction pillow between your legs keeps your hips in a safe position while you sit; the first few nights, your leg may be returned to the sling. To prevent your hip from dislocating before the ligaments heal enough to stabilize the area, you must avoid specific movements in the hospital and for several weeks at home (see “After hip surgery: Four tips to avoid dislocation”).
Before you can safely go home, you are usually expected to be able to perform the following: get into and out of bed, walk with crutches or a walker, go up and down both a curb and the number of steps you must negotiate at home, perform your rehab exercises, and show you can do necessary tasks with little or no assistance (and, after hip replacement, without violating your hip precautions). If you had knee replacement, you should be able to straighten your knee and bend it 90 degrees. Depending on individual circumstances, these requirements may be altered. If you are medically cleared for discharge but not able to do these things, or if you need extra nursing care or have no assistance at home, you are discharged to a rehabilitation center. Many people who live alone choose this option.
After knee or hip replacement, your implant is likely to set off a security alarm at an airport or building entrance. Cards explaining that you have a joint replacement are no longer accepted at airports. Security personnel may ask you to step to the side so they can run a wand past the area. If the wand emits a signal, they may pat down the area as an extra precaution
Back on track after joint replacement
A little planning and preparation before your joint replacement surgery can ease your recovery. For example.
Set up an area in your home in which you’ll spend most of your time. Position a phone, remote control, reading materials, medications, and water all within easy reach.
Make sure items you need daily—clothing, toiletries, pots and pans, food—are stored at arm height, so that reaching and bending isn’t necessary. Use a long-handled reaching tool for items beyond arm’s length.
Clear clutter and remove any rugs on which you might slip.
Cook and freeze foods that only need to be reheated, or stock up on prepared foods.
An apron with big pockets can help you carry things around your home, while leaving hands and arms free to use crutches or help you balance better.
Apply for a temporary disabled parking permit through your state department of motor vehicles. You’ll want to do this several weeks before your surgery. If you are having a right hip or knee replacement, be aware that driving is not recommended for six weeks after surgery, because your right foot controls the gas and the brake.
Figure 14: Exercises after knee replacement
Sitting knee bends: Sit in a chair with a towel under the operated knee. Straighten your knee as far as possible and hold for five seconds. Repeat 10 times. Gradually work up to 25 repetitions.
Standing knee bends: Hold on to a steady surface such as a table. Bend your operated knee back as far as it will go. Hold for five seconds, then lower the leg to the floor. Repeat 10 times. Gradually work up to 25 repetitions.
When you first arrive home, you’ll need help—a family member, friend, or person hired to assist with meal preparation, cleaning, bathing, shopping, and just fetching things you need. Depending on your medical condition, a visiting nurse or home health aide may be helpful.
Your degree of participation in a rehabilitation program is a major factor in the success of your implant. Think of yourself as an athlete training to come back from an injury. These first several weeks require much effort. Several times a day, you perform exercises your physical therapist has recommended to restore movement in the joint and strengthen the surrounding muscles (see Figures 14 and 15). You can do many of these exercises while sitting or lying down. A physical therapist may come to your home or schedule regular appointments for the first few weeks. In addition to formal exercises, gradually increasing the amount you walk and do normal tasks improves your strength and stamina.
How long you will need to use crutches or a walker to keep weight off your implant depends on individual circumstances. Whether your implant is cemented or uncemented, most surgeons permit you to bear weight as tolerated right away. Usually, you begin by putting just a little weight on the leg with the implant. As your postoperative pain decreases, you’ll gradually build up to bearing your full weight. You should be walking without crutches or a walker by four to six weeks, or possibly sooner. After about six weeks of healing, your rehabilitation goals shift toward restoring your ability to do normal activities, although you may still experience muscle pain and fatigue for several months as your tissues heal.
After six months you should be able to function pretty normally. You can expect to have as much movement as you had before the operation, but without the pain. Just don’t expect to have better mobility than you previously had.
Postsurgical pain. Pain is usually well controlled while you’re in the hospital, since doctors and nurses are nearby and can provide powerful medications intravenously. Once you return home, the pain level is hard to predict. Some people experience very little and can find relief with ordinary over-the-counter drugs. Others, however, have severe pain and are reluctant to even get out of bed.
It’s not always clear why a person may experience exceptional pain. It can be a matter of perception—people’s thresholds for pain vary tremendously. In other cases, there may be an underlying problem causing the pain, such as a swollen tendon or an infection.
Never suffer in silence. If your pain level is unacceptable, call your surgeon. If there’s an underlying cause, he or she can address it. For example, pain caused by a swollen tendon can be alleviated with a steroid shot, and infections can be cured with antibiotics. If there is no direct cause, the surgeon can prescribe a more powerful medication, such as oxycodone (OxyContin, Percocet). This drug is tightly regulated due to its potential for abuse and dependence, but it’s unlikely to be misused by pain patients and is generally effective. Your primary care physician is another good person to talk to if your pain is not being adequately managed.
Dos and don’ts: Post-surgery
These tips can help ensure that your return to mobility following surgery goes smoothly.
Do eat right. Eating a healthy diet, including lots of fruits, vegetables, whole grains, and lean protein is important to promote proper tissue healing and restore muscle strength.
Do learn the signs of blood clots. Warning signs of a leg clot include increasing pain, tenderness, redness, or swelling in your knee and leg. Signs a clot has traveled to your lung include shortness of breath and chest pain that comes on suddenly with coughing. Call your doctor if you develop any of these signs.
Do exercise wisely. Performing the exercises your physical therapist recommends is crucial to restoring movement in your new joint and strengthening the surrounding muscles.
Do look for signs of infection. These include persistent fever, shaking, chills, increasing redness or swelling of the knee, drainage from the surgical site, and increasing pain with both activity and rest.
Don’t take risks that could cause you to fall. Be especially careful on stairs until your joint feels strong. Use a cane, crutches, or a walker until you have improved your balance and strength.
Don’t soak your wound. Upon returning from the hospital, keep your wound dry until it has thoroughly sealed and dried.
Guidelines for recovery from knee or hip replacement
Ask your doctor and physical therapist how soon you can return to specific activities and what preparation will help you achieve those goals.
Driving. If your left knee was replaced and your car is an automatic, you may be able to drive as soon as you are not taking opioid medication and feel up to it. If the right knee was operated on, a wait of six weeks is typical. If pain previously hampered your ability to brake quickly, your reaction time may improve greatly after you have healed.
If you had a hip replaced, ask your physical therapist for guidance on getting in and out of the car and riding safely. Some vehicles are unacceptably high or low, forcing your hip into an unhealthy position. In some cars, sitting on a firm pillow can help you avoid overflexing your hip. On long drives, stop and get out at least once an hour.
To drive with a replacement hip, you need to be off opioid painkillers and blood thinners, able to put weight on your right leg (for an automatic transmission) or both legs (for a manual transmission), and able to brake without violating your current hip precautions. It usually takes about six weeks before you can drive an automatic and 12 weeks for a stick shift.
Work. After a knee replacement, you’ll probably be able to return to a desk job after six to eight weeks; a job requiring lots of standing, walking, or lifting may take twice as long. Avoid heavy lifting, which places significant stress on your implant. After a hip replacement, it may be three to six months until you can return to work, depending on the physical demands of your job. If you sit at a desk, your chair should have arms and be high enough to properly position your hips.
Sex. After a knee replacement, wait until the incisions and tissues in the front of the knee heal (about six weeks). If you usually put weight on your knees during sex, you may want to try a position that involves lying on your back or side or even sitting. For a hip replacement, you need to wait until muscles and incisions have healed. You may need to adjust your sexual positions. You might lie on your back or on your non-operated side, resting your operated leg on your partner’s leg. Don’t flex your hips more than 90 degrees, and don’t raise your knees higher than your hips. Avoid positions that rotate your hips out (either sitting or lying with knees wide apart).
Sports. By eight weeks after surgery, you may be able to resume activities such as golfing, bowling, ballroom dancing, biking (without great hills, for people with hip transplants), swimming (as long as the wounds have healed), or scuba diving. Be reasonable about what you can and cannot do. Some sports will never be advisable with a replacement knee or hip, because most implants won’t hold up to much of the jumping, twisting, or repeated jarring of running, soccer, basketball, volleyball, or other contact sports. And you’ll want to avoid activities that require jumping or heavy lifting, that might jolt or stress your hip or knee, or that make it likely you might fall or have something (or someone) bump into your replaced joint. That said, life is meant to be enjoyed, not just endured. So ask your doctor whether you can return to your favorite activities, perhaps with some modifications. Limited running—maybe one to two miles several times a week—may be possible, for example. Even skiing, doubles tennis, and hockey might be within reach, though such sports may shorten the life of your implant. A physical therapist can help tailor your rehab program to prepare you for the safest possible return to activities you enjoy.
Living with a replacement joint
Eventually, your knee or hip implant may feel like it is truly your own joint. However, complications can occur that shorten the life of an implant, and you may need to take certain precautions.
Infection. Your implant can become infected years after surgery, almost always because infection elsewhere in the body has spread to the area. Seek immediate treatment if you have symptoms of a urinary tract or other infection, and inform all your doctors that you have a joint replacement. At least for the first couple of years, you may be advised to take prophylactic antibiotics before medical procedures that often result in bacteria entering the bloodstream, such as invasive dental work (extractions, gum surgery, root canals, and any cleaning or procedure likely to result in bleeding), a colonoscopy, or any type of surgery. Your doctor can advise you on how long to continue these precautions, which are particularly important for people who have an illness or have undergone medical treatment that impairs the immune system.
Leg-length discrepancy. A difference in leg length occurs only rarely after knee replacement but occurs frequently, at least temporarily, after hip replacement. Before surgery, one leg is often shorter than the other—or feels shorter because the joint has deteriorated. Your orthopedic surgeon chooses an implant and plans surgery so that your legs will be equal in length after healing. After hip replacement, muscle weakness or spasm and swelling around the hip may temporarily cause an abnormal tilt to your pelvis and make you feel as though your legs are unequal in length. Stretching and strengthening exercises help restore your pelvis to its proper position (see Figure 15). It may be several months before you can tell if the discrepancy is real and needs to be addressed with the use of a lift in the shoe. When the discrepancy is accompanied by pain, surgery can correct both problems.
Figure 15: Exercises after hip replacement
Check with your physical therapist to find out if you are ready to do the following exercises to strengthen your hip.
Standing knee raises: Standing with the aid of a walker or holding a stable surface, lift your thigh and bend your knee. Hold for five to 10 seconds. Straighten your knee and touch the floor with your heel first. Repeat until your leg feels fatigued.
Standing with your hand on a stable surface, lift your leg out to the side as far as you can and hold for five to 10 seconds. Keep your hip, knee, and foot pointing straight forward. Repeat until your leg feels fatigued.
Dislocation. In the weeks after a hip replacement, you’ll need to take great care to keep from dislocating the implant before the surrounding tissues have healed enough to hold it in place. Even afterward, there is a chance of a painful dislocation—five out of every 100 implants dislocate after total hip replacement surgery. If your hip dislocates, your doctor gives you a sedative while he or she manipulates the implant ball back into the socket. A hip that dislocates more than once usually requires surgery to make the joint more stable.
Loosening. A replacement joint can loosen for several reasons. Perhaps the cement never secured it properly or eventually wore out, or the surrounding bone never grew into the implant to create a tight attachment. Perhaps bone supporting the implant was compromised by infection or bone resorption, possibly due to a reaction to wear-debris from a polyethylene implant. Loosening may require revision surgery.
After hip surgery: Four tips to avoid dislocation
Precautions against dislocating a new hip implant are quite limiting for about six weeks. It’s important to follow them regardless of how well you feel, since a position can be risky without causing pain.
Bone loss. As a joint implant suffers wear and tear, loose particles can be released into the joint. As your immune system attacks these foreign particles, it can also attack surrounding bone, weakening it in a process called osteolysis. This, in turn, may loosen the bone’s connection to the implant. Osteolysis is a major factor leading to revision surgery after hip and knee replacement.
Loosening, bone loss, being very active or overweight, and the wearing away of the artificial joint that typically occurs after 15 to 20 years can all necessitate revision surgery. Knee and hip replacements typically last longer in older people, since they tend to be less active than their younger counterparts, who put more wear and tear on a replacement joint. For knee or hip replacement surgery, there is a 1% failure rate per year (meaning that revision surgery is needed within one year).
If your implant fails, surgery to replace it takes longer and may be more complicated than your original operation. There is also more risk involved. The in-hospital death rate for revision hip replacements is more than double that of first-time total hip replacements. Patients who have less pain and fewer additional medical conditions before revision surgery are more likely to experience better pain relief as a result of the surgery.
More mobility = weight gain?
Many overweight people who have painful knees or hips anticipate that having a joint replacement will ultimately help them shed weight by helping them be more active.
While this expectation seems plausible, in many cases patients actually put on more weight after having surgery. A study in Orthopedics documented this phenomenon—at least one year following hip or knee replacement surgery, patients gained an average of three pounds, with younger patients adding the most weight.
Researchers aren’t sure why this occurs. One theory is that increased mobility after surgery leads people to make more frequent trips to the refrigerator and go out to eat more often. Whatever the reason, don’t assume that joint replacement surgery will automatically help you slim down. To lose weight, you’ll need to adhere to a regular exercise program and reduce your total caloric intake.
Look for a surgeon with experience doing both implants and revisions. Before you have revision surgery, your doctor will perform a thorough physical exam. If you’re much older than the first time around, you may need to take more precautions, such as banking extra blood for the lengthy procedure.
During surgery, the surgeon removes the old implant and damaged bone or joint tissue surrounding it. Depending on the amount and condition of the remaining bone tissue, you may need bone repairs or a bone graft to create a stable site for the new implant. Rehabilitation is similar to the initial replacement but takes longer after revision, and the outcome is often inferior. For example, your range of motion in the joint may be more restricted or your leg alignment less even, and even after healing you may need to use a cane to keep full weight off the joint.
Hopefully, with improved implant designs and newer materials such as cross-linked polyethylene, total joint replacements will last longer, making revision surgery less likely in the future.
American Academy of Orthopaedic Surgeons
This professional organization for orthopaedic surgeons provides patient fact sheets and booklets on numerous knee and hip problems. The website includes a physician locator.
American Academy of Physical Medicine and Rehabilitation
This professional organization is for physiatrists, physicians who specialize in rehabilitation. The website includes a physician locator.
American Physical Therapy Association
This national professional organization for physical therapists provides consumer brochures and other patient information. The website includes a locator for board-certified physical therapists with additional training in specific areas.
A national not-for-profit organization with local chapters in many states. The website has educational materials on joint surgery, arthritis, pain control, treatments, alternative therapies, and more, as well as exercise videos. Local chapters may offer joint-health exercise classes in a pool or on dry land.
Lose Weight and Keep it Off
Miguel Alonso-Alonso, M.D., and Julie Corliss
(Harvard Medical School, 2011)
This special health report from Harvard Medical School offers a range of solutions that have helped many people lose weight, and can be tailored to your specific needs. Take this challenge seriously, though, because overweight and obesity can lead to serious medical problems, including joint issues.
The Joint Pain Relief Workout: Healing Exercises for Your Shoulders, Hips, Knees, and Ankles
Edward M. Phillips, M.D., Josie Gardiner, Joy Prouty, and Francesca Coltrera (Harvard Medical School, 2012)
This report explains how to use the right blend of exercise to ease joint pain. Little or no equipment is needed. Four full workouts for shoulders, hips, knees, and ankles are included, along with a mini workout for wrists and elbows.
Walk with Ease
Arthritis Foundation, 3rd edition
(Arthritis Foundation, 2009)
An easy-to-follow walking program designed for people with arthritis. Includes information on different types of arthritis, why certain activities are especially helpful, what to do if exercise hurts, and positive solutions for problems that could crop up.
abduction: Movement of a body part away from the midline.
acetabulum: The socket of the hip’s ball-and-socket joint; part of the pelvic bone.
adduction: Movement of a body part toward or across the midline.
arthroplasty: Joint replacement.
arthroscopy: A surgical approach that uses miniature scopes and other small instruments inserted through small incisions to diagnose and repair joint problems.
articular cartilage: Tough, rubbery tissue that coats the surface of bones within joints.
bursae: Cushioning sacs containing lubricating fluid located at a point of friction between two moving structures, such as a muscle and a tendon.
bursitis: Inflammation of a bursa, causing swelling and pain.
chondrocalcinosis: Arthritis caused by calcium crystals.
condyles: The bony knobs of the knee joint located at the lower end of the femur.
crepitus: Grinding sensation or sound when a joint (especially the kneecap) is moved.
fibula: The smaller bone of the calf, located in the back.
gout: Arthritis caused by uric acid crystals.
inflammation: A response to injury or foreign invasion designed to protect the body; the symptoms are heat, redness, swelling, and pain.
ligament: Fibrous tissue connecting bones and cartilage.
tibia: The shin bone; the large bone of the lower leg.
Scott D. Martin, M.D.
Associate Professor of Orthopedics, Harvard Medical School, Department of Orthopedics and Sports Medicine,
Sports Medicine Fellowship Director, Brigham and Women’s Hospital
Editor, Special Health Reports
Published by Harvard Medical School
Anthony L. Komaroff, M.D., Editor in Chief
Edward Coburn, Publishing Director
In association with Belvoir Media Group, LLC
Robert Englander, Chairman and CEO
Timothy H. Cole, Executive Vice President and Editorial Director
Licensing and corporate sales
For the latest information and most up-to-date publication list, visit us online at www.health.harvard.edu