High Bifurcation of the Brachial Artery and Superficial Ulnar Artery: A Case Report and Prevalence Study in a Donor Population

Objectives: To describe the prevalence of a high bifurcation of the brachial artery and a superficial ulnar artery in a donor population of 17 individuals, the rare occurrence of both variations in one of the 17 individuals, and to explore the clinical, surgical, and embryological significance of both types of anatomical variations. Methods: During routine anatomical dissection of 17 formalin-fixed cadavers at Rocky Vista University College of Osteopathic Medicine- Southern Utah, 34 upper limbs were examined bilaterally for vascular anomalies. Standard dissection techniques were used to assess the origin, course, and branching of the brachial, radial, and ulnar arteries. Results: A unilateral case was identified with a high bifurcation of the brachial artery occurring approximately 2.54 cm distal to the teres major muscle. The ulnar artery coursed superficially over the forearm flexor mass before rejoining its typical path. The common interosseous artery originated anomalously from the radial artery. This combined vascular variation was found in one of the 34 upper extremities (2.94%), while high bifurcation alone was present in four of the 34 upper extremities (11.7%). Embryological review suggests abnormal regression or persistence of axial arterial branches may contribute to such variations. Conclusion: Although rare, recognition of a high bifurcation of the brachial artery with a superficial ulnar artery is critical for preventing complications during venipuncture, catheterization, and vascular surgery. This case underscores the importance of anatomical education and preoperative imaging when encountering vascular anomalies.