Posterior Muscles

p {margin: 0; padding: 0;} .ft00{font-size:19px;font-family:Arial;color:#ff0000;} .ft01{font-size:16px;font-family:MS-PGothic;color:#000000;} .ft02{font-size:16px;font-family:Arial;color:#000000;} .ft03{font-size:16px;font-family:ArialMT;color:#000000;} .ft04{font-size:16px;line-height:21px;font-family:ArialMT;color:#000000;} Posterior muscles ❉ Supraspinatus The supraspinatus extends from the supraspinatus fossa to the upper end of the humerus.During its course passes below the acromioclavicular joint and the acromiocoracoidligament, and above the scapulohumeral joint. It ends in a tendon adherent to the upper partof the capsule on the upper surface of the greater tuberosity. The supraspinatus has threeessential functions: - He is an abductor of the arm. - It applies the humeral head to theglenoid cavity during abduction and thus allows stabilization of the joint during deltoidcontraction. - It plays a role as an active ligament of the shoulder joint. ❉ Infraspinatus The infraspinatus connects the infraspinous fossa to the greater tuberosity on which it insertsoutside its middle facet by a flattened tendon. It is separated from the joint capsule by abursa. The infraspinatus is the external rotator and abductor of the arm. Like thesupraspinatus, it helps to maintain contact between the articular surfaces of theglenohumeral joint. ❉ Large circle This elongated muscle extends from the lower angle of the scapula to the bicipital slide.During its path, the teres major carries forward, passes under the subscapularis muscle andattaches to a flattened and broad tendon on the anterior surface of the humerus. Like thelatissimus dorsi, the teres major is the internal rotator and adductor of the arm. When thehumerus acts as a fixed point, the teres major elevates the shoulder stump and the lowerangle of the scapula. ❉ Small circle The teres minor is placed under the infraspinatus which it follows in its path from the externaledge of the scapula to the posterior surface of the humeral head. It is inserted on the lowerfacet of the greater tuberosity. The teres minor is the external rotator and abductor of thearm. ❉ Latissimus dorsi The latissimus dorsi is a very broad, flattened muscle that extends from the dorsal andlumbar region to the bicipital slide. It attaches to the spinous processes of the last six dorsalvertebrae and the five lumbar vertebrae, to the sacral and iliac crests, to the external face ofthe last four ribs to reach the bottom of the bicipital slide. The latissimus dorsi is an adductor,internal rotator and causes a retropulsion of the arm. When the fulcrum is the arm, thelatissimus dorsi becomes an elevator of the trunk.