A 19-year-old baseball player was referred for assessment of recurrent
sprains of the right ankle. This was found to be secondary to a palsy
of the common peroneal nerve that was compressed by an osteochondroma
of the fibular neck. The lesion was resected from the fibula and the
patient made a complete recovery. We present this case as an example o
f a rare underlying problem in a patient who was initially diagnosed a
s having a sports-related ankle injury.