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Acute compartment syndrome complicating tibial plateau fracture — MSRA MCQ

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HardKnee InjuriesAcute compartment syndrome complicating tibial plateau fractureMSRA

A 34-year-old man attends a GP-led urgent treatment centre 4 hours after his motorcycle struck a car. His right knee was forced into valgus while the foot was planted. He was initially assessed in the emergency department, where radiographs showed a minimally displaced lateral tibial plateau fracture. He was placed in an above-knee posterior slab and discharged for fracture-clinic review the following morning. He now reports rapidly escalating deep calf pain despite taking oral morphine. The pain is severe at rest and markedly worsens when his toes are passively extended. The calf is swollen and tense compared with the contralateral side. Dorsalis pedis and posterior tibial pulses are palpable, capillary refill is 2 seconds, and sensation and ankle movements are intact. What is the most appropriate management today?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: C — Transfer immediately to the emergency department with pre-alert for urgent orthopaedic assessment of acute compartment syndrome

Explanation lettering: E = shown as A · A = shown as B · D = shown as C · C = shown as D · B = shown as E

This is suspected acute compartment syndrome, requiring immediate transfer for urgent orthopaedic assessment. The decisive features are a high-risk tibial injury, rapidly escalating analgesia-resistant pain, a tense calf, and severe pain on passive stretch of muscles within the affected compartment. These are early features of compartment syndrome and take priority over defining associated intra-articular soft-tissue injury or routine fracture planning. Palpable distal pulses, normal capillary refill, preserved sensation and intact ankle movement do not exclude compartment syndrome: pulses are commonly retained until late, and pulselessness should instead prompt concern about concomitant arterial injury. The existing posterior slab may be contributory if restrictive, but changing it in an urgent treatment centre must not delay emergency escalation where clinical features are already strongly suggestive. A and E delay treatment for imaging that does not address the immediate limb-threatening complication. B is inappropriate because outpatient review is unsafe in evolving compartment syndrome. C is hazardous because increasing opioid analgesia and observation may mask progression; poor response to opioids is itself a concerning feature. ([rightdecisions.scot.nhs.uk](https://www.rightdecisions.scot.nhs.uk/north-of-scotland-major-trauma-guidelines/orthopaedicsplastics/compartment-syndrome/?utm_source=openai))

Reference: Compartment syndrome | North of Scotland Major Trauma Guidelines (Current page, checked 16 August 2026) — https://www.rightdecisions.scot.nhs.uk/north-of-scotland-major-trauma-guidelines/orthopaedicsplastics/compartment-syndrome/ Compartment syndrome (2022) — https://www.nhs.uk/conditions/compartment-syndrome/ Evaluation and Management of Acute Compartment Syndrome in the Emergency Department (2019) — https://pubmed.ncbi.nlm.nih.gov/30685220/