Infraspinous Fascia, Posterior View

Description

Posterior to the thorax, the infraspinous fascia spans the infraspinous fossa of the scapula, lying deep to the deltoid and superficial to the infraspinatus muscle belly and its tendon as it courses laterally toward the greater tubercle of the humerus. Superiorly, it meets the region of the scapular spine and the supraspinous fascia over the supraspinatus fossa; inferiorly it blends toward the lateral border near teres minor, while medially it approaches the vertebral border where the rhomboid major and minor attach deep to trapezius. Trapezius frames the midline from the nuchal region into the upper thoracic spine, with the scapulae positioned lateral to the spinous processes and the rounded deltoid caps forming the most lateral shoulder contour. A clean fascial plane. This posterior emphasis on the infraspinous fascia matters because it is one of the more teachable boundaries between rotator cuff musculature and the superficial deltoid envelope, and it helps orient the clinician to the scapular spine as a palpable landmark during shoulder examination. In rotator cuff disease, infraspinatus atrophy and tendon pathology often present as posterior shoulder weakness in external rotation, and correlating the fascial covering with the underlying muscle belly improves interpretation of physical findings and musculoskeletal ultrasound or MRI slices taken just inferior to the scapular spine. It also relates to posterior surgical exposures around the scapula, where separating deltoid from underlying cuff structures depends on respecting these tissue layers. Orthopaedic and sports medicine texts use this view when explaining posterior rotator cuff anatomy, scapular surface landmarks, and approaches to evaluating suspected infraspinatus tears or suprascapular nerve entrapment at the spinoglenoid notch. It also fits gross anatomy lab manuals, kinesiology courses focused on scapulohumeral rhythm, and patient-facing surgical consent materials that need a faithful posterior shoulder map. Anatomical accuracy verified by SciePro's Medical Advisory Board.