Bilateral anterior shoulder dislocations in bench pressing: an unusual cause.

A case of bilateral anterior glenohumeral dislocation in a young weight trainer is presented. The patient, an insurance clerk, had been using a free weight bar in the bench press position and had become tired when the weight on the bar forced his arms into hyperextension in the mid-abducted position. The humeral shaft gradually pivoted on the bench and the humeral heads were slowly dislocated anteriorly by the weight of the bar. Simple closed reduction under sedation was performed and there were no complications. After six weeks in bilateral broad arm slings, with pendulum exercises from two weeks, the patient began to mobilise his arms and he achieved a full range of movements. This unusual mechanism of injury has not previously been reported and we recommend that bench pressing should be performed with a weight that can be "locked" to prevent crushing of the user. Furthermore, the bench should be narrow enough to allow the shoulders to overhang, allowing greater extension in the abducted position without the arm pivoting on the edge of the bench.