Middle Collateral Artery, Posterior View

Description

Posterior anatomy of the male arm is rendered with the humerus in situ and the triceps brachii forming the dominant superficial mass, its long head positioned medially and its lateral head sweeping laterally over the posterior shaft. Along the posterior surface of the humerus, the middle collateral artery branches from the profunda brachii and descends within the lateral intermuscular septum toward the lateral epicondyle, running in close company with the radial nerve as both traverse the radial (spiral) groove. Distally, the vessel approaches the posterior aspect of the elbow where it contributes to the periarticular anastomoses around the lateral epicondyle, adjacent to the origins of the extensor compartment of the forearm. This posterior perspective matters because it clarifies the relationship between the profunda brachii system and the radial nerve at the level most relevant to injury. Midshaft humeral fractures and posterior approaches to the humerus place the radial nerve at risk, and the middle collateral artery can be a useful vascular landmark while you track the nerve’s course through the triceps interval. Arterial continuity at the elbow also becomes clinically relevant when brachial artery flow is compromised, as collateral pathways, including the middle collateral, help maintain distal perfusion. Use this plate in upper limb anatomy teaching to anchor the concept of posterior arm compartments, radial groove contents, and elbow collateral circulation, or in orthopedic and trauma publications discussing humeral shaft fracture patterns, posterior plating corridors, and iatrogenic radial nerve palsy. It also fits operative anatomy guides for elbow exposure where recognition of the lateral intermuscular septum and adjacent vessels helps orient dissection. Anatomical accuracy verified by SciePro's Medical Advisory Board.