Pes anserinus syndrome due to solitary tibial spurs and osteochondromas.

We studied 19 children with the pes anserinus syndrome due to proximal tibial exostoses. Nine children had a solitary sessile or pedunculated osteochondroma that produced a painful lump that was readily palpable. The symptoms resolved following removal of the osteochondroma. Ten children had a bone spur that was shaped like a rose thorn. It produced pain with snapping or a feeling of locking of the pes anserinus tendons. Careful palpation was required to detect the tender bone spur beneath the pes anserinus. In five children, the bone spurs were excised because of persistent symptoms, and each was shown to be an exostosis without a cartilage cap. The symptoms resolved. However, the bone spurs need not be excised if the symptoms improve with rest and do not recur following resumption of activities.