About one-fourth of all problems treated by orthopedic surgeons involve the knee, according to the American Academy of Orthopaedic Surgeons. Torn ligaments and cartilage are the bulk of the problems, but many knee ailments are lumped under the term "runner's knee," a loose heading for aches and pains involving the kneecap.
Runner's knee, which can strike cyclists, swimmers, basketball and volleyball players, step-aerobics fans, and runners, happens when the tendon below the kneecap becomes irritated from overuse or there is wear or arthritis under the kneecap. Sometimes, in knock-kneed people, leg muscles pull the kneecap out of the groove in which it normally slides up and down, causing painful grating on the cartilage. Flat-footedness also can cause kneecap displacement during exercise.
Prevention and treatment tips:
- Preventing runner's knee often involves simply replacing your worn-out shoes or insoles, which helps reduce impact. Switching from a hard to a soft running surface -- or from a hilly to a flat route -- also may relieve symptoms. Ask your doctor about shoe inserts called orthotics, which lift your arches and help position your feet so impact doesn't lead to misalignment at the kneecaps.
- To help hold your kneecap in line, strengthen your quadriceps, the front thigh muscles. Getting more rest and cross-training can also help prevent overusing one set of muscles. A tried-and-true rule in sports medicine may help you avoid doing too much too soon. The "10 percent rule" says to increase the frequency, duration, and intensity of an activity by only 10 percent per week. So, if you start walking 10 miles the first week, you would walk no more than 11 miles the second week.
- If you get a bad case of runner's knee, take two days off and anti-inflammatory medication, such as ibuprofen. After two days, be sure to warm up and cool down and to ice your knee for 20 minutes after the workout.
- Strengthening and stretching the muscle is key, says Lewis G. Maharam, M.D., a New York City sports medicine specialist. He recommends using a weight machine to do leg extensions, concentrating on the last 30 degrees of the extension. This isolates the thigh muscles that help hold the kneecap in line. "Within eight weeks of doing this exercise regularly, runner's knee is pretty much under control," he says.
Note: Women are especially vulnerable to ligament injuries and other knee disorders. A study by Edward Wojtys, M.D., of the University of Michigan Medical School, found that female athletes had more knee laxity, less muscle strength and endurance, and different muscle reaction time than male athletes, even when strength was corrected for body weight. These factors have contributed to a large rise in women's knee injuries, two to eight times the level found in male athletes.