Athletic Injuries 101: Separated Shoulder

In this edition of Athletic Injuries 101, Dr. Sarah Ytsma explains the separated shoulder, including an explanation, causes, and treatment of a separated shoulder.

DEFINITION

The “AC” joint is anatomically known as the ACROMIOCLAVICULAR joint, or the joint that forms on the top part of the shoulder between the acromion, a portion of the scapula or shoulder blade, and distal portion of the clavicle or the collar bone. When someone injuries this joint it is commonly referred to as a SEPARATED SHOULDER.

PATHOPHYSIOLOGY

Typically, the most common way to injure the AC joint is through direct trauma on the joint such as getting checked into the boards during hockey or falling directly on the shoulder during football, skiing, snowboarding, etc. Occasionally, the AC joint can become problematic if the anatomy of the acromion differs from the norm.

TYPES OF AC JOINTS

Type 1: flat acromion is just as it says, flat along the bottom.
Type 2: curved acromion has a slight rounded appearance and is the most common type.
Type 3: also known as a hooked acromion, this can easily lead to rotator cuff impingement syndromes with overuse of the shoulder, improper weight lifting techniques, and poor postural syndromes. The hooked portion at the tip of the acromion creates less room for the supraspinatus tendon that runs through the glenohumeral joint, creating possible impingement at the shoulder. These are often candidates for surgery as chronic impingement at this area will often lead to a rotator cuff tear.

DEGREE’S OF SEPARATION

REHABILITATION/OUTCOME

Type’s V and VI are very rare to happen. Surgery is required for types III – VI to repair the ligaments. Extensive rehabilitation is required after surgery. Type I and II separation can be helped significantly with rehab. Ice, rest, and support of the arm are required after immediate injury. Range of motion and strength must be restored after initial pain and swelling have subsided.