Anatomy study and clinical significance about the spatial distribution of the recurrent branch of median nerve

Objective To provide anatomical data for avoiding the injury of the recurrent branch of median nerve (RBMN) through the proximal operative incision of the carpal thenar region. Methods Thirty adult upper limb specimens (16 formaldehyde fixed specimens and 14 fresh frozen specimens) were dissected. The origin of the RBMN, the angle between the RBMN and the longitudinal axis of the median nerve main trunk, the location of the first bifurcation point of the RBMN, the distribution of the superficial branch and the deep branch of the RBMN were measured, and the relationship between the RBMN and the proximal, middle and distal regions of the thenar was observed. Results The origin of the trunk of the RBMN located in the proximal and middle third of the thenar area account for 46.7% and 52.3%, respectively. After the RBMN originated from the main trunk of the median nerve, it moved towards the radial side at an average angle of 48.6° (range, 20° to 70°). The first bifurcation point of RBMN located in the proximal and middle third of the thenar area account for 56.7% and 43.3%, respectively. 96.7% deep branch and 56.7% superficial branch were located in the proximal third of the thenar area. Conclusion The RBMN and its terminal branches were mostly located in the proximal third of the thenar area, and any operation in this area should pay attention to avoiding injury. Key words: Median nerve; Anatomy; Recurrent branch; Clinical significance