Acromioclavicular Joint Sprain (Separated Shoulder)

Acromioclavicular (AC) joint sprains are injuries to the ligaments at the joint where the clavicle
(collarbone) articulates with the acromion (roof of the shoulder) of the scapula (shoulder
blade). These injuries are commonly referred to as “shoulder separations” and represent
injuries to the acromioclavicular ligaments between the clavicle and the acromion and the
coracoclavicular ligaments between the coracoid and the clavicle. A sprain indicates that the
ligament between the bones is either partially or completely torn which affects the stability of
the acromioclavicular joint. AC joint sprains are graded I through VI from least to most severe.