Traumatic Conditions (Dislocations): Acromio-Clavicular Disruption

Dislocations of the acromio-clavicular (A-C) joint are common, usually being caused by a fall onto the point of the shoulder. There is an apparent upward displacement of the end of the clavicle, though it is the whole of the shoulder girdle on the affected side which has sagged to leave the clavicle prominent. This is due to rupture of the coracoclavicular ligaments which have a suspensory function for the upper limb.

The majority of A-C joint dislocations recover to a reasonable degree of function in three weeks with a simple sling and analgesia, and only the most severe need surgery. In the ED, do not confuse this injury with a distal clavicular fracture: an x-ray may be helpful.

The literature [1] suggests that the long-term results of operative and non-operative treatment are balanced.

Click on the x-rays to enlarge.

Fig 1: A-C joint disruption, conservatively managed	Fig 2: A-C joint disruption (Tossy 3) requiring surgery

Learning bite

Stress x-rays are not required in the majority of cases, and may even look normal, due to the upward pull of the trapezius on the scapula.