|Classification and external resources|
Chondromalacia patellae (also known as CMP) is inflammation of the underside of the patella. While it often affects young individuals engaged in active sports it also afflicts older adults who overwork their knees.
While the term chondromalacia sometimes refers to abnormal-appearing cartilage anywhere in the body, it most commonly denotes irritation of the underside of the kneecap (or "patella"). The patella's posterior surface is covered with a layer of smooth cartilage, which the base of the femur normally glides effortlessly against when the knee is bent. However, in some individuals the kneecap tends to rub against one side of the knee joint, irritating the cartilage and causing knee pain.
The condition may result from acute injury to the patella or chronic friction between the patella and a groove in the femur through which it passes during knee flexion. Possible causes include a tight iliotibial band, neuromas, bursitis, overuse, malalignment, core instability, and patellar maltracking.
Pain at the front or inner side of the knee is common in both young adults and those of more advanced years, especially when engaging in soccer, gymnastics, cycling, rowing, tennis, ballet, basketball, horseback riding, volleyball, running, figure skating, snowboarding, skateboarding, and even swimming. The pain is typically felt after prolonged sitting." Skateboarders most commonly experience this injury in their non-dominant foot due to the constant kicking and twisting required of it.Swimmers acquire it doing the breaststroke, which demands an unusal motion of the knee.
In the absence of cartilage damage pain at the front of the knee due to overuse can be managed with a combination of RICE (rest, ice, compression, elevation), anti-inflammatory medications, and physiotherapy.
Usually chondromalacia develops without swelling or bruising. While treatment remains controversial, most individuals benefit from rest and adherence to an appropriate physical therapy program. Allowing inflammation to subside while avoiding irritating activities for several weeks is followed by a gradual resumption. Cross-training activities such as swimming can help to maintain general fitness until a physical therapy program emphasizing strengthening and flexibility of the hip and thigh muscles can be undertaken. Use of nonsteroidal anti-inflammatory medication is also helpful to minimize the swelling amplifying patellar pain. Treatment with surgery is declining in popularity due to positive non-surgical outcomes and the relative ineffectiveness of surgical intervention.
See also 
- Knee pain
- Patellofemoral pain syndrome
- Knee osteoarthritis
- Plica syndrome
- Iliotibial band syndrome
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