Shoulder of the rotator cuff are supraspinatus, subscapularis, infraspinatus, and teres minor. The cuff adheres to the glenohumeral capsule and attaches to the humeral head. The shoulder must be mobile enough for the wide range actions of the arms and hands, but stable enough to allow for actions such as lifting, pushing, and pulling. The shoulder consists of a ball-and-socket joint formed by the humerus and scapula and their surrounding structures - ligaments, muscles, tendons - which support the bones and maintain the relationship of one to another. These supporting structures attach to the clavicle, humerus, and scapula, the latter providing
Annular ligaments of fingers Annular ligaments of fingers In human anatomy, the annular ligaments of the fingers, often referred to as A pulleys, are the annular part of the fibrous sheathes of the fingers. Four or five such annular pulleys, together with three cruciate pulleys, form a fibro-osseous tunnel on the palmar aspect of the hand through which passes the deep and superficial flexor tendons. The annular and cruciate ligaments serve to govern the flexor mechanism of the hand and wrist, providing critical constraints to the flexor tendons to prevent bowstringing upon contraction and excursion of extrinsic flexor musculo-tendinous units. The first annular pulley