RESUMEN
BACKGROUND: Accessory Deep Peroneal Nerve (ADPN) is an anatomic variation that can potentially cause disturbance in electrodiagnostic studies. This anomaly could be detected by nerve conduction studies. There are no recent updates about prevalence of this anatomic variation. Electrodiagnostic medicine clinic is the best environment for detecting presence and prevalence of this nerve, so present study enrolled. MATERIALS & METHODS: In this cross sectional descriptive study that take place from March 2009 to July 2010, 230 cases comprising 460 legs referred for electrodiagnostic studies of upper limbs problems participated in the study. Compound muscle action potential (CMAP) and Nerve conduction Velocity (NCV) of Deep Peroneal Nerve (DPN) were measured by using EMG machine by stimulating DPN at knee, ankle and lateral malleolous areas accordingly, with recording from extensor digitorum brevis muscle. Results were analyzed and conclusion made. RESULTS: The study population included 120 females (52%) and 110 (47%) males with mean age of 42.1 ± 13.5 years. ADPN was detected in 28 patients (12%). Among them,10(17.9%) had bilateral ADPN and in remained 18 cases (82.1%) APN was unilateral. In 8 patients there was no recorded CMAP from EDB by proximal and distal stimulation implying EDB agenesis. Gender distribution was similar which means half of the cases (14 patients) belonged to each gender. CONCLUSION: The prevalence of ADPN in this study was 12.2%, (17.9% bilateral and 82.1% unilateral).