Shoulder problem that attach the shoulder muscles to bone and assist the muscles in moving the shoulder. Ligaments attach shoulder bones to each other, providing stability. For example, the front of the joint capsule is anchored by three glenohumeral ligaments. The rotator cuff is a structure composed of tendons that, with associated muscles, holds the ball at the top of the humerus in the glenoid socket and provides mobility and strength to the shoulder joint. Four filmy sac-like structures called bursa permit smooth gliding between bone, muscle, and tendon. They cushion and protect the rotator cuff from the bony arch of the
Glenohumeral ligaments capsule is strengthened in front by two bands derived from the tendons of the Pectoralis major and Teres major respectively. During abduction of the arm the middle and inferior ligaments become taut while the superior ligament relaxes. The radius of curvature of the head of the humerus is greater superiorly than inferiorly, which further stretches these ligaments so that they keep the articular surfaces of the joint in their close-packed position. During abduction the greater tubercle of the humerus comes in contact with the upper margin of the glenoid cavity, which limits maximum abduction. By rotating the humerus laterally, this