Chondromalacia Patellae

Kneecap pain, often called Runner's Knee

Chondromalacia patellae is a common cause of kneecap pain. Often called Runner's Knee, this condition often affects young, otherwise healthy athletes. The problem is due to an irritation of the undersurface of the kneecap. The undersurface of the kneecap, or patella, is covered with a layer of smooth cartilage. This is supposed to glide effortlessly across the knee during bending of the joint. However, in some individuals, the kneecap tends to rub against one side of the knee joint, and the cartilage surface become irritated.

Chondromalacia is due to changes of the deepest layers of cartilage, causing ¡®blistering¡¯ of the surface cartilage. This pattern of cartilage damage is distinct from the degeneration seen in osteoarthritis, and the damage from chondromalacia is thought to be capable of repair, unlike that seen in osteoarthritis.

Chondromalacia is interesting in that it often strikes young, otherwise healthy, athletic individuals. Women are more commonly affected with chondromalacia. Exactly why this is the case is unknown, but it is thought to have to do with anatomical differences between men and women, in which women experience increased lateral forces on the patella.

The treatment of this disorder remains controversial, but most individuals can be effectively treated by resting the knee and adhering to a proper physical therapy program. Allowing the inflammation to settle is the first step. Avoiding painful activities that irritate the knee for several weeks, followed by a gradual return to activity is important. In this time, cross-training activities such as swimming can allow an athlete to maintain their fitness while resting the knee. A physical therapy program should emphasize strengthening and flexibility of the quadriceps and hamstring muscle groups. Use of nonsteroidal anti-inflammatory medication is also helpful to minimize the pain associated with this condition. Surgical intervention is declining in popularity for two reasons: good outcomes without surgery, and the small number of patients who actually benefit from surgical intervention.

However, some patients are not cured by conservative therapy, and it may be determined that surgery is needed. By looking into the knee with an arthroscope, the surgeon can assess the damage done to the cartilage. He or she can also assess the mechanics of the joint to ascertain if there is an anatomic misalignment that could be corrected. One common misalignment is due to abnormal tracking of the patella (tracking is simply the movement of the patella as the knee moves) caused by too much lateral tension. For this problem, a procedure known as a lateral release can be performed. This procedure involves cutting the tight lateral ligaments to allow for normal position and tracking of the patella. If this is not sufficient to correct the misalignment there are more extensive surgeries which can be performed.