Humeral Circumflex Anastomosis

rete circumflexum humeri

The humeral circumflex anastomosis is the arterial network formed by the anterior and posterior circumflex humeral arteries around the surgical neck of the humerus, supplemented by branches of the profunda brachii and acromial vessels. This anastomosis maintains humeral head perfusion when individual circumflex vessels are interrupted.

Region: Upper Arm

Clinical Relevance

Clinical Notes

The humeral circumflex anastomosis is critical in proximal humeral fractures, where disruption of the arcuate artery (the ascending branch of the anterior circumflex humeral) risks avascular necrosis of the humeral head. Fibular free flap to shoulder reconstruction and reverse shoulder arthroplasty preserve this anastomotic network to maintain deltoid vascularity. The anastomosis is the basis for the deltoid flap and the posterior circumflex humeral artery perforator flap.

Pathology

Common Injuries & Conditions

Humeral Head Avascular Necrosis

Disruption of the humeral circumflex anastomosis in displaced four-part proximal humeral fractures, cutting off humeral head perfusion and producing avascular necrosis in 13-34% of four-part fractures managed non-operatively.