Triceps Muscles, Gross Anatomy

Description

Posterior upper trunk and arm are rendered with the scapulae flanking the thoracic spine and the proximal humerus descending inferiorly from the glenohumeral joint. Overlying the posterolateral shoulder, the deltoid caps the humeral head, while the triceps brachii occupies the posterior compartment of the arm with its long head coursing medially from the infraglenoid tubercle of the scapula and the lateral and medial heads arising from the posterior humeral shaft. Distally, the three heads converge into the triceps tendon toward the olecranon, forming the familiar posterior arm contour. Understanding the triceps in a back view matters because it clarifies what sits superficial and what crosses the shoulder joint. The long head is a frequent landmark in posterior approaches to the shoulder and proximal humerus and helps frame the quadrangular space (with teres minor and major and the surgical neck of the humerus), where the axillary nerve and posterior circumflex humeral artery run and can be injured with shoulder dislocation or surgical neck fractures. It also supports teaching of elbow extension mechanics and why triceps weakness can follow radial nerve injury in the spiral groove. Faculty commonly select this plate for gross anatomy lab manuals, upper limb dissection guides, and orthopedic or sports medicine chapters discussing posterior arm compartments, shoulder landmarks, and triceps tendon pathology near the olecranon. It also suits patient-facing educational handouts for postoperative counseling after proximal humerus fixation or posterior shoulder procedures. Anatomical accuracy verified by SciePro's Medical Advisory Board.