Anatomical Structure And Location Of The Scapula's Spine

Description

Scapular spine (spina scapulae) dominates the posterior surface of the shoulder blade as a thick, triangular bony ridge running transversely from the medial border toward the lateral angle. Laterally, the spine expands into the acromion, which projects anterolaterally over the glenohumeral joint, while the spine itself separates the supraspinous fossa superiorly from the infraspinous fossa inferiorly. Along its superior and inferior lips, the illustration emphasizes the roughened attachment areas for trapezius and deltoid, with the medial root of the spine positioned closest to the vertebral border and the acromial end forming the roofline of the subacromial space. Clinically, this landmark matters because the spine and acromion define key corridors for shoulder examination and intervention, and their contours influence subacromial impingement patterns and acromioclavicular joint mechanics. The fixed posterior emphasis makes it easy to teach how the scapular spine guides palpation for scapular orientation (upward rotation, winging), and why fractures at the spine base or acromion can disrupt deltoid and trapezius force couples during abduction. Bony relief is the message. The spine’s position relative to the supraspinatus and infraspinatus fossae also supports discussions of rotator cuff topography when correlating surface anatomy with ultrasound or MRI findings. Use this illustration in gross anatomy and kinesiology courses to anchor scapular landmarks, or in orthopedic and sports medicine materials covering acromial morphology, scapular dyskinesis, and posterior shoulder approaches. It also fits patient education graphics on shoulder blade pain and acromioclavicular sprain, where naming the scapula, spine, and acromion correctly reduces ambiguity. Anatomical accuracy verified by SciePro's Medical Advisory Board.