Regional anatomy of median nerve palmar cutaneous branch and its clinical significance

Abstract

Objective To provide anatomic data for avoiding injury of the palmar cutaneous branch (PCB) of the median nerve during operation around the wrist and palm.Methods The origin,course,branching,distribution and blood supply of the PCB of the median nerve were observed and measured in dissections of 52 adult cadaver upper extremity specimens.Results PCB existed in all 52 specimens originating from the radial side of the median nerve in 50 and from the ulnar side in 2.PCB ran in the deep side between the palmaris longus and flexor carpi radialis tendon.The distance from PCB origin to the zero point (the midpoint of the distal wrist crease) was (45.2 ± 21.2) mm.The point where PCB piercing the forearm deep fascia was (19.8 ± 12.3) mm from the zero point,while the point where PCB piercing the palm aponeurosis was (8.2 ± 4.3) mm from the zero point.The length of PCB before branching was (49.2 ± 24.2) mm,while the width at its beginning was (1.2 ± 0.7) mm.The vertical distance of PCB to the scaphoid tubercle midpoint was (8.3±2.8) mm.3 branches of PCB were found in 31 specimens (59.6％),2 branches in 15 specimens (28.9％) and 1 branch in 6 specimens (11.5％).Distribution of the PCB was mainly in the thenar and midpalm area.Palmar cutaneous branch nutritional artery either entered the PCB directly,accompanying it or by way of muscular branch.Conclusion The origin and course of PCB is relatively constant.Surgical incisions at the wrist or palm should be ulnar to the longitudinal axis of the ring finger and close to the fourth metacarpal,to avoid inadvertent injury of the median nerve PCB and its nutrient vessels. Key words: Median nerve; Palmar cutaneous branch; Applied anatomy; Vascular