Bilateral asymmetrical variation of median artery in coexistence with bifid median nerve and variation in the origin and course of its palmar cutaneous branch: a case study with clinical implications

The median artery typically regresses after two months of intrauterine life, although it may persist into adulthood in some individuals. The presence of a persistent median artery (PMA) may be associated with other anatomical variations including a bifid median nerve. In the present cadaveric study, we report a rare variation of bilateral asymmetry of PMA associated with the bifid median nerve, and unilateral variation of the origin and course of the palmar cutaneous branch of the median nerve (PCBMN) which to our knowledge, is the first study to report all these variations in an individual. Classical dissection of the upper limb was performed on a 45-year-old male cadaver. The cadaver was donated to the Department of Anatomy at Kerman University of Medical Sciences. Bilateral PMA was observed in both upper limbs. The PMA originated from the ulnar artery and contributed to the formation of an incomplete superficial palmar arch (SPA) on both sides; however, the branching pattern of these arteries was different between the right and left hands. Also, a bilateral high division of the median nerve was observed proximal to the carpal tunnel. We also encountered a very rare variation of PCBMN, in which it originated from the ulnar side of the median nerve, and passed beneath the flexor retinaculum of the left hand. Awareness of anatomical variations of the median nerve and also the presence of PMA is of utmost importance due to their implication in carpal tunnel syndrome and surgical complications.