A rare bilateral neurovascular variation of the upper limb: A case report of a 97-year-old Caucasian male

Introduction Numerous review articles have described variations to the branching pattern of the vasculature [3, 8, 10] and innervation [1, 4,] in the upper limbs of cadavers. The classification of the arterial patterns that we used for this report corresponded to McCormick et al.’s [8] description of radial artery origin proximal to the intercondylar line. Multiple names have been given to this variant artery: Drizenko et al. [3] named it a highorigin radial artery, whereas Rodriquez et al. [10] called it the brachioradial artery. Such variations are additionally known to be relatively common, with McCormick et al. [8] reporting that departures from the typical arterial branching pattern in the upper limb occurred in 30.77% of cadavers, with bilateral variations in 6.32%. McCormick et al. [8] also reported that a radial artery of high origin accounted for 77% of all upper-limb variations. Rodriquez-Niedenfuhr [10] reported that the instances of high-origin radial artery occurred in 14.27% of all specimens, and of those, 65.5% originated from the brachial artery. Our arterial variation, consisting of the radial recurrent artery originating from the ulnar artery on the left and the superior ulnar collateral artery originating from the variant high-origin radial artery on the right, was not reported in these arterial variation review articles [8, 10, 3]. Additionally, to our knowledge, this variation has not been reported in the numerous original case studies published in the scientific literature. There are a multitude of articles reporting on the variations of the brachial plexus. Variations to the musculocutaneous and median nerve were reported in 43% [4] to 46.4% [1] of cadavers, with a communicating branch between the two nerves in 43% [4]. Additionally, the absence of normal musculocutaneous innervation to the coracobrachialis was found in 11.1% [4] to 13.7% [1] of cadavers.