Diagnostic Biopsy of a Motor Branch of the Superficial Peroneal Nerve to the Peroneus Longus: A Convenient Alternative for Motor Nerve Biopsy.

Abstract

Motor nerve biopsy is performed to supplement clinical, serologic, and imaging data in the workup of neuropathies of unknown origin, especially when motor neuron disease is suspected. We describe a surgical technique for biopsy of a motor branch of the superficial peroneal nerve innervating the peroneus longus muscle. Three patients presented with weakness concerning for motor neuropathy and underwent biopsy of a motor branch of the superficial peroneal nerve innervating the peroneus longus muscle. The surgical technique is described in detail. Biopsied tissue was sufficient for pathologic diagnosis. No patient suffered postsurgical sensory or motor deficits related to the procedure. No patient suffered postsurgical complications. Biopsy of the motor branch of the superficial peroneal nerve to the peroneus longus is a safe and effective alternative for motor nerve biopsy and can be easily combined with peroneus longus muscle biopsy.