Infraspinatus Muscle

Description

Posterior shoulder musculature is rendered in a male figure with the deltoid muscle emphasized, and the underlying rotator cuff anatomy organized around the scapula. Deep to the posterior deltoid, the infraspinatus occupies the infraspinous fossa inferior to the spine of the scapula, its fibers converging laterally toward a tendon that blends with the posterior glenohumeral capsule before inserting on the middle facet of the greater tubercle of the humerus. Superior to it lies supraspinatus at the supraspinous fossa, while teres minor runs along the lateral border of the scapula inferior and slightly lateral to infraspinatus, with teres major and latissimus dorsi positioned more inferiorly and anteriorly at the posterior axillary fold. Surface landmarks read clearly. Clinically, isolating the infraspinatus in a posterior view helps correlate external rotation strength testing with rotator cuff integrity, since infraspinatus and teres minor generate most of the resisted external rotation torque with the elbow flexed at 90 degrees. The course of the suprascapular nerve is a key teaching point in this region: compression at the spinoglenoid notch produces selective infraspinatus denervation and visible atrophy in the infraspinous fossa while sparing supraspinatus, a pattern often discussed in overhead athletes and patients with paralabral cysts. This is the anatomy that informs posterior arthroscopic portal placement and safe dissection planes around the scapular spine and glenoid. Use this artwork for rotator cuff modules in gross anatomy, kinesiology, and orthopedic or sports medicine teaching files, and for publisher figures that need accurate layering between the deltoid and the posterior cuff. It also fits patient education materials on rotator cuff tears, suprascapular neuropathy, and postoperative rehabilitation focused on restoring external rotation. Anatomical accuracy verified by SciePro's Medical Advisory Board.