Unilateral Anatomical Variation of the Suprascapular and Dorsal Scapular Arteries: A Cadaveric Case Report

While most anatomical variations in cervical neurovasculature remain asymptomatic throughout life, clinical impacts may arise during surgical procedures, potentially worsening patient outcomes. This case report highlights two unique anatomical variations observed in the arteries of the right neck and shoulder regions of a 75-year-old Caucasian male donor body. The first variation was the origin of the suprascapular artery (SSA), the primary blood supply to two of the four rotator cuff muscles. The SSA arose directly from the first part of the axillary artery instead of the thyrocervical trunk off the subclavian artery (SA). The vessel passed over the lower trunk and continued obliquely between the contributions of the upper and middle trunks to the lateral cord of the brachial plexus before coursing posteriorly, where it divided further into two branches. While one branch continued to the supraspinous fossa, the second branch split into three smaller branches to supply the subscapularis muscle. The second variation concerned the dorsal scapular artery. The artery emerged normally from the third part of the SA but provided branches to the supraspinatus muscle in addition to its normal blood supply to the rhomboid and levator scapulae muscles. Knowledge of potential anatomical variations of the origin and distribution of the branches of the SA is crucial for surgeons, given the importance of this vasculature. Awareness and prior identification of variations such as those presented in this report can help avoid potential complications in surgical procedures.