Asymmetrical Axillary Artery Deviations of the Brachial Plexus

Introduction: The relationship between the brachial plexus and other key axillary vascular structures have been explored extensively in medical literature highlighting different variations in the brachial plexus. Understanding variations provides valuable knowledge for surgical interventions. Typically at the axillary region, the lateral cord splits into the musculocutaneous nerve and the lateral root of the median nerve. The medial cord contributes the medial root to the median nerve where the axillary artery normally runs posteriorly.

Objective: The goal of this case report is to highlight a bilateral anatomical variation of the brachial plexus in relation of the progression of the axillary artery in a 71 year-old male cadaver.

Methods: During a routine dissection in a medical school Anatomy course, the axilla of a male cadaver was dissected bilaterally according to laboratory protocol. Digital photography was used to preserve visual observations.

Results: In the right axilla, the joining of the lateral root and medial root to form the median nerve occurs proximally in the axillary region. This junction occurs more distally in the brachial region of the left arm. In the left axilla, the axillary artery is running between the superior anterior division and the middle anterior division from anteriorly to posteriorly. More distally, the axillary emerges from the posterior side coming over the median nerve. The right axillary region has an axillary artery running above the median nerve as well.

Conclusion: Knowledge of anatomical variations in the brachial plexus is important for anatomists and surgeons during interventional procedures including nerve blocks and surgery. Here we report a unique variation of the brachial plexus and the position of the axillary artery in the left axilla as well as the right axilla.