Retrotendinous calcification of the infrapatellar tendon: unusual cause of anterior knee pain syndrome.

Bilateral anterior knee pain is a common presentation to the orthopaedist. Correct diagnosis is based on careful history and physical examination aided by proper radiographs. Erroneous diagnosis may lead to improper treatment. This report describes a case of bilateral anterior knee pain syndrome of 3 years' duration. The teenaged patient was believed to be suffering from seronegative rheumatoid arthritis. Her pain persisted despite numerous antirheumatoid medications as well as a single injection of steroids into each infrapatellar tendon. The management of her case by means of arthroscopic surgical intervention is described.