ChondromalaciaChondromalacia refers to softening of the articular cartilage of the kneecap. The disorder occurs most often in young adults and may be caused by trauma, overuse, parts out of alignment, or muscle weakness. Instead of gliding smoothly across the lower end of the thigh bone, the kneecap rubs against it, thereby roughening the cartilage underneath the kneecap. Traumatic chondromalacia occurs when a blow to the knee cap tears off either a small piece of articular cartilage or a large fragment containing a piece of bone.
Symptoms of ChondromalaciaThe most frequent symptom of chondromalacia is a dull pain around or under the kneecap that worsens when walking down stairs or hills. A person may also feel pain when climbing stairs or during other activities when the knee bears weight as it is straightened. The disorder is common in runners and is also seen in skiers, cyclists, and soccer players. A patient's description of symptoms and a followup x ray usually help the doctor make a diagnosis. Although arthroscopy can confirm the diagnosis of chondromalacia, it is not performed unless the condition requires extensive treatment.
Chondromalacia TreatmentsMany doctors recommend that patients with chondromalacia perform low-impact exercises that strengthen muscles, particularly the inner part of the quadriceps, without injuring joints. Swimming, riding a stationary bicycle, and using a cross-country ski machine are acceptable as long as the knee is not bent more than 90 degrees. Electrical stimulation may also be used to strengthen the muscles. If these treatments fail to improve the condition, the physician may perform arthroscopic surgery to smooth the surface of the articular cartilage and wash out cartilage fragments that cause the joint to catch during bending and straightening. In more severe cases of chondromalacia, surgery may be necessary to correct the angle of the kneecap and relieve friction involving the cartilage or to reposition parts that are out of alignment.
Injuries to the MeniscusThe two menisci are easily injured by the force of rotating the knee while bearing weight. A partial or total tear of a meniscus may occur when a person quickly twists or rotates the upper leg while the foot stays still (for example, when dribbling a basketball around an opponent or turning to hit a tennis ball). If the tear is tiny, the meniscus stays connected to the front and back of the knee; if the tear is large, the meniscus may be left hanging by a thread of cartilage. The seriousness of a tear depends on its location and extent.
SymptomsGenerally, when people injure a meniscus, they feel some pain, particularly when the knee is straightened. The pain may be mild, and the person may continue activity. Severe pain may occur if a fragment of the meniscus catches between the femur and tibia. Swelling may occur soon after injury if blood vessels are disrupted, or swelling may occur several hours later if the joint fills with fluid produced by the joint lining (synovium) as a result of inflammation. If the synovium is injured, it may become inflamed and produce fluid to protect itself. This causes swelling of the knee. Sometimes, an injury that occurred in the past but was not treated becomes painful months or years later, particularly if the knee is injured a second time. After any injury the knee may click, lock, or feel weak. Symptoms of meniscal injury may disappear on their own but frequently, symptoms persist or return and require treatment.
DiagnosisIn addition to listening to the patient's description of the onset of pain and swelling, the physician may perform a physical examination and take x rays of the knee. The examination may include a test in which the doctor flexes (bends) the leg then rotates the leg outward and inward while extending it. Pain or an audible click suggests a meniscal tear. An MRI test may be recommended to confirm the diagnosis. Occasionally, the doctor may use arthroscopy to help diagnose and treat a meniscal tear.
TreatmentIf the tear is minor and the pain and other symptoms go away, the doctor may recommend a muscle-strengthening program, such as:
- Warming up the joint by riding a stationary bicycle, then straightening and raising the leg (but avoiding straightening the leg too much).
- Extending the leg while sitting (a weight may be worn on the ankle for this exercise).
- Raising the leg while lying on the stomach.
- Exercising in a pool, including walking as fast as possible in chest-deep water, performing small flutter kicks while holding onto the side of the pool, and raising each leg to 90 degrees in chest-deep water while pressing the back against the side of the pool.