Long Head of the Triceps Brachii, Posterior View

Description

Positioned on the posterior arm of an adult male, the long head of triceps brachii is traced proximally to its scapular attachment at the infraglenoid tubercle, just inferior to the glenoid cavity, then followed distally as it converges with the lateral and medial heads toward the common triceps tendon. Medially, the long head forms a clear boundary with the posterior axillary fold alongside latissimus dorsi and teres major, while laterally it lies adjacent to the deltoid and the surgical neck region of the humerus. Distal to the midarm, the muscle belly narrows toward the olecranon insertion, with posterior forearm extensor compartments and wrist tendons rendered for continuity. Clean posterior topography. For teaching, this posterior perspective clarifies a frequent point of confusion: the long head is the only triceps head crossing the glenohumeral joint, so it contributes to shoulder extension and adduction as well as elbow extension. That relationship matters when distinguishing posterior shoulder pain from primary elbow extensor pathology, and it is also the key landmark when discussing the triangular interval, where the radial nerve and profunda brachii artery pass inferior to teres major and lateral to the long head. It also supports surgical orientation for posterior approaches to the arm and for nerve injury patterns in humeral shaft fractures. Anatomy faculty can drop this plate directly into upper-limb dissection guides, kinesiology modules on elbow extension, and exam items contrasting biceps brachii and triceps brachii actions and attachments. Medical publishers will find it suited to chapters on posterior arm compartments, axillary region boundaries, and clinical correlations such as radial neuropathy and triceps tendon injury. Anatomical accuracy verified by SciePro's Medical Advisory Board.