Chondromalacia patellae

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Overview
Chondromalacia Patellae (also known as CMP, Patello-femoral Pain Syndrome, or Runner's Knee) is a degenerative condition of the cartilage surface of the back of the knee cap, or patella. It produces discomfort or dull pain around or behind the patella. It is common in young adults, especially football players, cyclists, rowers, tennis players, ballet dancers and runners. Snowboarders are particularly prone to this injury, especially those specializing in jumps where the knees are under great stress. The condition may result from acute injury to the patella or from chronic friction between the patella and the groove in the femur through which it passes during motion of the knee. CMP specifically refers to a knee that has been structurally damaged, while the more generic term Patello-femoral Pain Syndrome refers to the earlier stages of the condition, where symptoms might still be fully reversible.

Causes
The term "chondromalacia" is a term left over from the 20th century. In the early 1900s investigators in Europe developed the theory that soft cartilage (the literal translation of chondro-malacia) is the cause of pain at the front of the knee. By the end of the 20th century, that theory had been discredited, but health professionals continued to use the term to describe patients with pain at the front of the knee. The term is still used today, but with diminishing frequency. It is gradually being replaced by the term "patellofemoral syndrome", a term used by clinicians when they do not have a specific explanation for a patient's pain. "Chondromalacia" and "Patellofemoral Syndrome" are now recognized to encompass a large and disparate group of medical conditions that can cause pain at the front of the knee. These include a tight iliotibial band, neuromas, bursitis, overuse, malalignment, core instability, to name but a few. The term chondromalacia can also be used to describe abnormal appearing cartilage (anywhere in the body). A Radiologist might, for example, note chondromalacia on an MRI of an ankle. There is no one "cause" of chondromalacia. There are as many causes as there are conditions lumped under the term "chondromalacia".

Treatment
The treatment will depend on the specific source of a person's pain. As noted above, "chondromalacia" and "patello femoral syndrome" are not diagnoses, as they do not help explain the source of pain. If pain is due to a tight iliotibial band, treatment will be focused on stretching of that band. If a person suffers from irritation of the infrapatellar branch of the saphenous nerve, treatment might consist of a small injection. If core stability is the issue, treatment might consist of physical therapy focused on the abdomen, pelvis and hips.