Intraneural ganglion cyst of the common peroneal nerve causing foot drop in a 12-year old child.

Objectives: Intraneural ganglia are benign fluid-filled cysts contained within the subepineurial space of peripheral nerves. The common peroneal nerve at the fibular neck is by far the most frequently involved, although other nerves can be affected as well. Although the differential diagnosis of foot drop in adults and children show some differences, clinical presentation, diagnostic workup, treatment and follow-up of intraneural ganglia are quite similar in both groups.