Common Fibular (Peroneal) Nerve Injury (L4-S2)

A Common Fibular (Peroneal) Nerve Injury (L4-S2) affects a nerve that controls muscles and sensation in the lower leg and foot. This nerve runs near the knee and can be easily injured by trauma, compression, or prolonged leg crossing. When damaged, it can cause foot drop, which means difficulty lifting the front part of the foot, leading to a distinctive high-stepping walk to avoid tripping. People may also experience numbness or tingling on the outer part of the lower leg and the top of the foot. This condition impacts the nervous system and can significantly affect mobility and balance.

Common Fibular (Peroneal) Nerve Injury (L4-S2) is a peripheral neuropathy resulting from damage to the common fibular nerve, which originates from the L4-S2 nerve roots. The injury commonly occurs due to trauma (such as knee dislocation or fibular head fracture), compression (from leg crossing or casts), or iatrogenic causes during surgery. The nerve innervates the anterior and lateral compartments of the leg, controlling dorsiflexion and eversion of the foot, as well as providing sensory innervation to the lateral leg and dorsum of the foot. Clinically, this injury manifests as foot drop, weakness in ankle dorsiflexion and eversion, and sensory deficits in the nerve distribution. It is significant because it impairs gait and increases the risk of falls. Electrophysiological studies often confirm the diagnosis and help localize the lesion.