Sprained Shoulder Anatomy
To better understand shoulder sprain, it helps to understand the anatomy of the shoulder joint.
The shoulder joint allows motion between two major bones: the humerus and the scapula. The shoulder joint is a ball and socket joint. A depression in the scapula, known as the glenoid, provides the socket for the head of the humerus. Ligaments and muscles hold the joint together as the bones move.
The clavicle, or collar bone, connects to the scapula at the acromion, which is a bony projection off the scapula. The acromioclavicular ligaments normally surround and secure this joint.
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