Infraspinatus Muscle, Posterior View

Description

Occupying the infraspinous fossa on the posterior surface of the scapula, the infraspinatus spreads inferior to the spine of the scapula and tapers laterally into its tendon as it approaches the humeral head. Fibers course superolaterally toward the greater tubercle of the humerus, deep to the posterior deltoid and adjacent to the posterior margin of the glenohumeral joint. Superiorly, the muscle lies near the scapular spine and acromion, while inferiorly it blends toward the region shared with teres minor along the lateral border of the scapula. Orientation is clear. Posterior shoulder anatomy is where rotator cuff pathology stops being abstract. The infraspinatus tendon is a frequent component of posterosuperior cuff tears, and this perspective supports teaching why fatty infiltration of the infraspinatus on MRI correlates with chronicity and poorer repair outcomes. It also maps cleanly onto the posterior arthroscopic portal concept, where instrument trajectory skirts the posterior deltoid and targets the cuff footprint on the greater tubercle without violating the joint capsule unnecessarily. Use this artwork in musculoskeletal anatomy and kinesiology courses to link fiber direction with external rotation mechanics, or in orthopedic and sports medicine materials discussing impingement, cuff tear patterns, and post-operative rehabilitation. It also fits surgical atlases and patient education handouts explaining why posterior shoulder pain can reflect infraspinatus tendinopathy or referred pain from the rotator cuff rather than the cervical spine. Anatomical accuracy verified by SciePro's Medical Advisory Board.