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Posterior shoulder dislocation — RCPSC EM MCQ

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ModerateMusculoskeletalPosterior shoulder dislocationRCPSC EM

A 42-year-old has shoulder pain after a witnessed seizure. The arm is held adducted and internally rotated, external rotation is blocked, and AP radiograph shows a lightbulb appearance of the humeral head. What is the most likely diagnosis?

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Correct answer: A — Posterior shoulder dislocation

Posterior shoulder dislocation is correct: the clues indicate Posterior shoulder dislocation and this option addresses the immediate ED priority. The distractors delay care, target a less likely problem, or are unsafe in this physiology.

Reference: Canadian EM orthopaedic practice