Anatomy and function of the subdeltoid bursa.
An anatomical study was undertaken on 40 non-embalmed normal cadaver shoulders to determine the attachments, boundaries and macroscopic nerve supply of the subdeltoid bursa. Two areas of attachment were observed, one (proximal and superficial) along the free border of the coracoacromial ligament and adjacent deep surface of deltoid, the other (distal and deep) to the humerus distal to the supraspinatus tendon: there were no posterior or anterior attachments. In addition, two blind pouches were observed, one proximal under the coracoacromial ligament and the other beyond the distal attachment. The continuity observed between the lateral border of the coracoacromial ligament and the subdeltoid bursa provides a smooth surface, thereby casting doubt on the aggressive action of the ligament on the rotator cuff.