Anatomical Variation of the Median Nerve and Accompanying Subclavius Posticus Muscle: a Cadaveric Case Report

The median nerve and subclavius muscle are two critical neuromuscular structures of the upper extremity. Although their anatomical variations are well described in the literature, a case report involving both anatomical variations in the same extremity is rare. Here, we report a case involving different anatomical variations in the median nerve formation and aberrant subclavius posticus muscle. During routine dissection, a rare anatomical variation was encountered in the left upper extremity of an adult male cadaver. In this case report, we observed two distinct findings in the left upper extremity of a 66-year-old male cadaver: a variant basilic vein passing between the lateral and medial roots of the median nerve and the presence of the subclavius posticus muscle. To our knowledge, a case involving an unusual basilic vein passing between the lateral and medial roots of the median nerve and an aberrant subclavian posticus muscle in the same extremity has not been reported to date. Knowledge of such variations may be useful for surgeons in avoiding iatrogenic injuries during anaesthetic and surgical procedures around the axilla and arm.