Background
The spectrum of bicycle riding injuries is extremely wide. However, compression peroneal neuropathy complicating a bicycle injury has not been previously reported.
Material and Method
An 11-year-old girl with common peroneal neuropathy is presented. Her knee was caught in between the chain stay and the crank arm on the left side of her bicycle and was jammed. Clinical examination indicated a motor paralysis producing foot drop and a sensory deficit over the lateral calf and the dorsum of the foot. Magnetic resonance imaging (MRI), although not diagnostic, provided useful information regarding soft tissue injury in relation to the common peroneal nerve's course in the popliteal fossa. An electrodiagnostic (EDX) study was indicative of a common peroneal neuropathy. Complete recovery of the peroneal nerve was noted 7 months post-injury.
Results

Conclusions
Compression peroneal neuropathy may be included in traumatic bicycle-related injuries, while the space between the chain stay and the crank arm on the left side of the bicycle may be recognized as potentially hazardous to entrap the rider's leg.

Keywords: Soft Tissue Injuries - pathology, Peroneal Neuropathies - pathology, Paralysis - etiology, Nerve Compression Syndromes - pathology, Foot Injuries - pathology, Child, Bicycling, Accidents, Tibia - pathology