Musculoskeletal and Orthopaedic Emergencies
Limb-threatening injuries
Compartment syndrome is the diagnosis most often missed. The earliest reliable sign is pain out of proportion to the injury, worsened by passive stretch of the compartment muscles. Pulses are usually present, and pallor, paraesthesia, paralysis and pulselessness are late features. Measure compartment pressure when uncertain: a delta pressure (diastolic minus compartment pressure) below 30 mmHg supports fasciotomy, but strong clinical suspicion alone justifies it.
Open fractures: antibiotics within one hour, tetanus prophylaxis, photograph the wound, cover with a saline-soaked dressing, splint, and document neurovascular status before and after.
Knee: apply the Ottawa knee rules before ordering radiographs; an effusion with fever suggests septic arthritis - aspirate before antibiotics. Hip: an elderly patient unable to weight bear after a fall needs urgent imaging; occult fractures may need MRI.
Spine: use the Canadian C-spine rule to avoid unnecessary immobilisation, respecting its exclusions. Back pain with saddle anaesthesia, urinary retention or bilateral leg weakness is cauda equina syndrome - emergency MRI, not analgesia and discharge.
Dislocations: reduce promptly, document distal neurovascular status, and obtain post-reduction films.
Rule of thumb: pain that is severe, progressive and worse on passive stretch is compartment syndrome until measured otherwise.