Did you know that knee-replacement surgery is virtually epidemic in this country? The number has doubled over the past decade. And among Medicare beneficiaries, the number of knee replacements has increased by more than 160%. One recent research paper reported that 4 million Americans now have knee implants—including half a million who had to have their knee replacement redone at least once. What explains all the extra knee replacements?

Am I being a cynic to suspect that a lot of unnecessary operations are being done? No, I’m not…and there are things you must know before letting someone cut out your knee…


A recent study showed that just about one-third of all knee replacements are inappropriate. The patients had relatively low levels of pain that could have been managed in other ways, and/or their knee X-rays showed little evidence of substantial arthritic changes. Many patients who were inappropriately given knee replacements were under age 55, and for them, considering that the life expectancy of the artificial joint is 15 to 20 years, another—and then perhaps another—arduous replacement operation will be needed.

Why are so many people so willingly getting an operation that is expensive, can take a year for full recovery and is certainly not without serious risks, including deadly blood clots? I spoke with Mitchell Yass, DPT, the founder and owner of PT2 Physical Therapy and Personal Training, to get his take because he is a leading authority on physical therapy and an outspoken critic of overdiagnosis and misdiagnosis of musculoskeletal pain. According to Yass, most patients—and their doctors—jump to the conclusion that they need a knee replacement because of pain due to arthritis, but pain is not a reason for knee replacement or necessarily a sign of knee arthritis.

Studies that have looked at pain in relation to arthritic changes have shown that only about 15% of people with X-ray evidence of knee arthritis actually have knee pain. One study even showed that sham surgery relieved knee pain caused by osteoarthritis just as well as real surgery. “Clearly the relationship between osteoarthritis and knee pain cannot be directly correlated,” said Yass.


“Most people who suffer knee pain experience the pain around the kneecap. The pain is caused by an imbalance in the strength of the quadriceps muscles on the front of the thigh and the hamstring muscle on the back of it. The quadriceps naturally get a lot more use from walking and everyday activity and naturally tend to be much stronger than the hamstrings,” Yass said. When the hamstring muscles are weaker than the quads, the quads shorten. This increases tension on the kneecap. Instead of painlessly gliding along with the joint, the kneecap presses against the joint…painfully.

Another possible, but less likely, cause of knee pain, Yass said, is either a strain on the quadriceps or the band of connective tissue that runs from the hip to the outer side of the kneecap (called the iliotibial band). Strain on the quads will cause the kneecap to “float” outward, and strain on the iliotibial band will cause the knee cap to edge toward the left or right side of the knee joint. Either way, when the knee bends or straightens, the kneecap rubs against points in the knee joint that it shouldn’t, causing pain.


“Joints are nothing more than ‘pivot points’ that exist solely to allow range of motion,” Yass said. “When a joint has undergone arthritic changes severe enough to prevent motion, then and only then is surgery warranted.” To be sure, there are people whose knees have been so degraded by wear and tear that replacement is the only current option to provide them with normal use of their knee. But Yass suggests that those people are actually rather few and far between. Rather than knee-replacement surgery, most people with knee pain need exercise to keep leg and knee muscles balanced and toned.

If you have knee pain, consider trying the exercises below to improve and balance your leg muscles and avoid the type of knee symptoms that have convinced too many people—and their doctors—that they need knee-replacement surgery. (Do check with your doctor first—but there is seldom a good medical reason not to try exercises before going to surgery.) How many reps should you do? Do each exercise 10 times, take a one-minute break, then repeat two more sets. How frequently? Two or three times a week.

DHN Loosen quads• Loosen the Quads. Stand near a wall for support. If your left knee is the most bothersome, turn your right side to the wall and rest your right hand against it. Then, reach back with your left hand to grip your left foot or ankle. Gently pull the foot toward the buttocks until you feel a stretch in the front of your thigh. Hold for about 20 to 30 seconds. Repeat on the other side whether or not you have problems with the other knee to keep all the muscles in balance.

Straight leg dead lift exercise• Strengthen the Hamstrings. Practice the straight leg dead lift. To do this, stand with your legs hip width apart, hands at hip level either holding hand weights or grasping a pole (such a broomstick) horizontally in front of you. Bend forward from your hips, keeping your legs straight (without “locking” your knees) and letting your hands (holding weights or a pole) run down your thighs until you begin to feel a pull at the back of the thighs. Then immediately return to the start position. Do three sets of 10 repetitions.

• Strengthen the Calves. In Yass’s experience, strengthening the calves can help offset excessive tightening of the quads and can strengthen the hamstrings. To do this exercise, stand facing a wall, counter or sturdy chair and place both hands on it to keep your balance. Rise up onto the balls of the feet (lifting your heels)…then, gently lower your heels to the ground. Once you feel that you can keep your balance when doing this exercise, you can hold dumbbells, which will create more muscle resistance and help strengthen the calves even more.

By the third week of doing these exercises, you should notice a significant improvement, said Yass. But even if you are completely rid of pain, you ought to keep up your exercise routine to keep the pain from returning. “You have to keep your muscles strong your entire life to keep them functional,” said Yass. “It’s like brushing your teeth to keep decay away.”