Open Tibial Shaft Fracture with a Suspected Compartment Syndrome
A 24-year-old man is brought in 90 minutes after a motorcycle collision. He has an open fracture of the left tibial shaft with a 6 cm anteromedial wound; the tibia is visibly protruding and there is gross instability. Blood pressure is 92/58 mmHg, heart rate 124/min, and he has received 1 L crystalloid. The anterior compartment is tense, passive dorsiflexion of the toes is painful, and sensation over the first web space is reduced; the dorsalis pedis pulse is palpable and the foot is warm. Haemoglobin is 9.6 g/dL. The wound is contaminated with road debris. The hospital has no plastic surgery on site; the nearest flap unit is 200 km away. The orthopaedic registrar is in theatre and the emergency physician asks you whether to send him for CT angiography before any intervention.
1. State your immediate priorities in the first hour and justify each, including antibiotic choice and whether imaging should precede treatment.
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Immediate priorities follow ATLS. Control catastrophic haemorrhage with direct pressure and splinting, then address airway, breathing and circulation. This patient is tachycardic and hypotensive, so assume significant blood loss, give blood rather than more crystalloid, and involve anaesthesia early.
Antibiotics within one hour of arrival improve outcomes in open fractures: cefazolin 2 g IV plus gentamicin 5 mg/kg for a Gustilo-Anderson IIIA injury, with benzylpenicillin added for soil contamination or clostridial risk, plus tetanus toxoid and immunoglobulin as indicated. Photograph and dress the wound, and do not repeatedly inspect it.
Imaging: CT angiography is not indicated before debridement when pulses are palpable and the foot is warm; it would only delay care. Plain radiographs of the whole tibia and fibula suffice. Angiography is reserved for absent pulses, an expanding haematoma, or a cold, pulseless foot.
Debridement within 6-12 hours, analgesia, NPO status, and keeping the limb at heart level complete the first hour. Do not elevate the limb above the heart.
2. Explain how you would confirm and treat the suspected compartment syndrome, including pressure thresholds and technique.
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Compartment syndrome here is primarily a clinical diagnosis: a tense anterior compartment, pain on passive stretch, and paraesthesia in the first web space. Pulses may remain palpable, so their presence does not exclude it.
If the patient is reliable and cooperative, clinical signs are enough to proceed to fasciotomy at the time of debridement. If examination is unreliable because of sedation, head injury or a regional block, measure compartment pressures with a side-port needle or an arterial-line transducer, within 5 cm of the fracture and in all compartments. Use the delta pressure (diastolic pressure minus compartment pressure); a delta of less than 30 mmHg indicates decompression. Absolute pressure above 30-40 mmHg alone is less reliable, particularly in a hypotensive patient.
Treatment is urgent four-compartment fasciotomy through anterolateral and posteromedial incisions, done at the same anaesthetic as the debridement. Release all constricting bandages and casts, keep the limb at heart level, leave wounds open with negative-pressure dressings, and plan a second look at 48 hours. Monitor CK, urine output and myoglobinuria.
3. Outline the sequence for skeletal stabilisation and soft-tissue cover, including the role of the external fixator and timing of referral.
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Skeletal stabilisation: a spanning external fixator is the safe choice if the patient is physiologically borderline, the wound is heavily contaminated, or the soft-tissue reconstructive plan is uncertain. Reamed intramedullary nailing is acceptable for a IIIA fracture if debridement is adequate and performed within 12 hours, and it gives better alignment and earlier weight-bearing. If in doubt, damage-control external fixation followed by conversion to a nail once the soft tissues settle is reasonable.
Soft-tissue cover: leave the wound open, apply negative-pressure therapy, and plan a second look with further debridement at 48 hours. Communicate early with the nearest plastic surgery unit, because definitive cover should ideally be achieved within 7 days; a free flap is likely to be needed for a 6 cm anteromedial defect with exposed bone. Send tissue cultures at debridement and start organism-directed therapy when results are available, usually at 48-72 hours. Never close the wound under tension, and counsel the patient about the risk of infection, non-union and amputation.