Scapula - Bone
Scapula
Anatomy:
- Supraspinous fossa - superior to the spine
- Infraspinous fossa - inferior to the spine
- Body – triangular surface of scapula
- Superior angle – projects superomedially
- Inferior angle - projects inferiorly
- Lateral angle – projects laterally; includes the glenoid cavity
- Superior border - extends from the glenoid cavity to the superior angle
- Lateral (aka axillary) border - extends from the inferior angle to the lateral angle
- Medial (aka vertebral) border - extends from the superior angle to the inferior angle
- Subscapular fossa - anterior surface of the scapula; it is the attachment site for subscapularis
- Acromion - the most-superior extension of the scapula and arises from the scapula's posterior surface
- Coracoid process - extends from the superior aspect of the scapula and projects laterally
- Glenoid cavity (aka fossa) - laterally oriented cup-shaped depression where the humerus articulates with the pectoral girdle
- Glenoid labrum - rim of the glenoid cavity, composed of fibrocartilage and aids in humeral stabilization
- Supra- and infraglenoid tubercles - raised portions of bone above and below the glenoid cavity that provide muscle attachment sites for the biceps brachii and triceps brachii
- Scapular neck - the portion of the scapula that extends toward the glenoid cavity
- Spine of the scapula - prominent ridge of bone that separates the posterior scapula into superior and inferior portions
- Acromion process - projects laterally; it is a continuation of the spine of the scapula
- Suprascapular notch - a small indentation in the superior border medial to the coracoid process
- Superior transverse ligament - closes off this notch superiorly to create a foramen through which the suprascapular nerve traverses.
- Calcification of the superior transverse ligament can compress the suprascapular nerve and impair innervation to the posterior scapular muscles
- The scapula articulates with the acromial end of the clavicle and the head of the humerus (upper arm).