A High Origin Subscapular Trunk and its Clinical Implications
Anatomy & Physiology
Important variations in the arrangement of branches of the axillary artery revolve around the origin of the subscapular artery. The case of a "high origin" subscapular artery as a common trunk to lateral thoracic, common circumflex humeral trunk in the left upper limb of a 72 year-old female cadaver, is discussed. This variant trunk originated posterior to the pectoralis minor muscle about 2-3 cm posteroinferior to that of the thoracoaromial artery. Trunk formations in the axillary artery with
... illary artery with four or more branches sharing a common stem of origin are infrequent compared with those with fewer numbers. In certain surgical orthopedic procedures, surgeons sometimes administer a ligature in the 3 rd part of the artery, relying on a suprascapular/dorsal scapular-circumflex scapular colateral pathway to dump blood into the artery distal to the ligature. Surgeons engaged in placing such ligature should be aware of proximal origin of the subscapular artery, as in the case of high origin of the artery being presented to guide placements of such ligature. Incorrect ligature placement distal to the origin of the subscapular artery would result in blood being dumped proximal to the clamped site, resulting in posible ischemia, gangrene and limb loss. Preoperative vascular imaging is advocated during surgical interventions in the shoulder region to assist in the selection of appropriate procedure to help needed in the reduction of iatrogenic complications and in assisting radiologists in the correct interpretation of images.