The "fabella syndrome": an update.

Sixteen adolescents presented with symptoms referable to the posterior lateral compartment of the knee, specifically the region of the fabella. The salient features of the syndrome include intermittent pain in the posterolateral region, accentuated by knee extension and localized tenderness when the fabella is compressed against the femoral condyle. The condition appears to be unique to late adolescence (15-17 years of age). Five patients responded to conservative measures. Eleven patients required surgery, all of whom obtained immediate relief of symptoms with removal of the ossified fabella, cartilaginous fabella, or thickened gastrocnemius fibers.