Shoulder Joint
Synovial capsule and ligaments at lateral end of clavicle, anterolateral view.
Observe:
1. The attachments of the four rotator cuff muscles prevent the capsule (purple) from extending onto the lesser and greater tubercles of the humerus, but it extends inferiorly onto the surgical neck of the humerus;
2. The capsule has two prolongations: (a) where it forms a synovial sheath for the tendon of the long head of the biceps muscle in its osseofibrous tunnel, and (b) inferior to the coracoid process, where it forms a bursa between the subscapularis tendon and margin of the glenoid cavity.
Anterior view of upper limb
Anterior view of the bones of the upper limb.
The shoulder is a ball-and-socket joint. It is made up of three bones: the upper arm bone (humerus), shoulder blade (scapula), and collarbone (clavicle).
Posterior view of upper limb
Posterior view of the bones of the upper limb.
The shoulder is a ball-and-socket joint. It is made up of three bones: the upper arm bone (humerus), shoulder blade (scapula), and collarbone (clavicle).
The ball at the top end of the upper arm bone fits into a small socket (glenoid) of the shoulder blade to form the shoulder joint. The shoulder joint moves with a smooth motion due to the smooth, durable surface (articular cartilage) on the head of the arm bone.
The upper part of the shoulder blade (acromion) projects over the shoulder joint. One side of the collarbone is joined with the shoulder blade by the acromioclavicular (AC) joint.
Glenohumeral ligaments and rotator cuff
Dissection, lateral view
The joint capsule is a thin sheet of fibers that surrounds the shoulder joint. The capsule allows a wide range of motion yet provides stability. The rotator cuff is a group of muscles and tendons that attach your upper arm to your shoulder blade. The rotator cuff covers the shoulder joint and joint capsule. The muscles attached to the rotator cuff enable you to lift your arm, reach overhead, and take part in activities such as throwing or swimming.
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