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What is shoulder separation?


A shoulder separation is an injury to the complex shoulder joint area. It is most definitely not similar to a shoulder dislocation.

The shoulder is in fact a double junction of bones. The top of the arm and the shoulder blade meet in a ball and socket joint where the arm swings from. However the shoulder blade also meets the collar bone in a sliding joint above the ball and socket.

The collar bone (clavicle) slides into an outcrop of the shoulder blade (scapula). This outcrop (the acromion) and the clavicle can slide against each other and provide cover and support above the ball and socket joint of the arm. The two joints and three bones are linked by ligaments.

A shoulder separation injury is a pushing apart of the clavicle and acromion and is sometimes called an acromioclavicular separation injury. (AC for short.) The ligaments holding the two bones together are pulled or torn and the bones move out of place.

This injury is almost always caused by a sharp blow to the shoulder area, often by a pushing of the arm upwards into the top joint. The injury is mostly caused in contact sports such as football where tackling is strong and you may fall with the extra weight of another man on top of you applying addition pressure. Falling from a height such as from a horse or obstacle is also a possibility. A simple fall from the ground is unlikely to provide the force necessary.

The injury causes immediate pain and there is usually swelling and sometimes even bleeding. Different grades of AC injury show increasingly large bumps above the shoulder where the clavicle is pushed up out of line. It is also possible, although rarer, for the clavicle to be pushed under the shoulder blade. In any of these cases, immediate Orthopedic attendance should be sought.

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