Kneecap Dysplasia

Dysplasia is where the shape of the kneecap and the groove it sits in on the lower end of the thigh bone simply don’t match each other. This creates abnormal pressure points on the surfaces and they wear out causing grating and pain (Kneecap Arthritis). Where one or both surfaces are too flat, kneecap instability (Kneecap Subluxation/Dislocation)can occur, and this can also cause damage to the surfaces and possibly kneecap arthritis after a long period of time.
The condition is surprisingly common and is often associated with other structural abnormalities of the kneecap.
Treatment is extremely difficult, as it is not easy to change the shape of the kneecap or its groove (called the femoral trochlea). Activity reduction and modification combined with patella stabilizing exercises and bracing can be effective and help but do not usually fully cure the problem.
Occasionally open surgery is necessary to change the shape of the kneecap and/or its groove.