Lower Leg Compartment Fasciotomy

Indication. Acute compartment syndrome of the leg is a surgical emergency diagnosed clinically — pain out of proportion to the visible injury, pain on passive stretch of the compartment muscles, and a tense, swollen leg. Once the diagnosis is made, the leg is taken to theatre for emergency four-compartment fasciotomy without delay.

When the picture is unclear. Pressure monitoring is an adjunct, not a substitute for clinical judgement. The accepted threshold is a delta pressure (diastolic blood pressure minus compartment pressure) of less than 30 mmHg. Absolute pressures are less reliable because they do not account for systemic hypotension.

Why the two-incision technique. The two-incision (lateral plus medial) approach is the standard of care and reliably decompresses all four compartments. Single-incision techniques have been described but carry a higher risk of incomplete deep posterior release. Endoscopic or limited-incision techniques are not recommended in the acute setting. Consent. Counsel regarding incomplete release, nerve injury (superficial peroneal, saphenous, tibial), infection, the need for skin grafting, amputation (rare, in delayed cases), and chronic pain or foot drop. Setup. Supine on a radiolucent table, leg prepared and draped free from thigh to toes, thigh tourniquet applied but not inflated unless required for vascular control. General or regional anaesthesia — note that spinal or epidural may mask early symptoms in the contralateral leg. Equipment: a soft-tissue set with long Metzenbaum scissors or a fasciotome, headlamp or loupe magnification, compartment pressure monitor if used, and vessel loops or Penrose drains for nerve identification.

The goal is to release all four fascial compartments of the leg through two long incisions, protect the nerves and vessels that cross the field, assess and debride non-viable muscle, and leave every wound open. The exposure is the operation — the two incisions are placed so that each opens directly onto the compartment fascia it must divide, and the danger structures are identified before any fascia is cut.

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Immediate post-operative care - Continue close observation for 24-48 hours — missed or recurrent compartment syndrome can still occur.

• Monitor the contralateral leg if the patient is at risk (bilateral injury, prolonged surgery).
• Keep wounds moist with saline dressings or negative-pressure therapy; change every 24-48 hours.
• Second-look debridement at 24-48 hours for any questionable muscle.
• Elevate the leg above heart level at rest. Avoid circumferential dressings or casts. Delayed closure or grafting Most wounds are ready for closure or grafting between day 5 and day 7, once swelling has subsided and healthy granulation tissue is present. Techniques: - Delayed primary closure — approximate wound edges with staples or sutures over a vessel loop or elastic band (the shoelace technique).
• Skin grafting — split-thickness skin graft (0.012-0.015 inch) meshed 1.5:1 or 2:1.
• Flap coverage — rarely required unless bone or tendon is exposed, or for large defects in the distal third. If swelling persists, continue negative-pressure therapy and reassess in 48 hours. Rehabilitation | Phase | Timing | Weight-bearing | Therapy focus | |-------|--------|----------------|---------------| | 1 | 0-2 weeks | Non-weight-bearing / touch weight-bearing | Active ankle and toe range of motion within pain limits; no resistance | | 2 | 2-6 weeks | Progressive, as wounds allow | Gentle resistance (isometrics to isotonics); scar massage once grafts mature | | 3 | 6-12 weeks | Full weight-bearing | Strengthening and proprioception; light work or sport-specific training | | 4 | 3-6 months | Full activity | Gradual return to full activity; monitor for late contractures (equinus, claw toes) | Expected outcomes With timely fasciotomy (less than 6 hours), greater than 90 percent of patients regain near-normal function. Delayed fasciotomy (greater than 12 hours) is associated with a 20-50 percent rate of permanent disability, infection or amputation. Foot drop from deep peroneal nerve injury or anterior compartment muscle loss occurs in 5-15 percent of cases and may require an ankle-foot orthosis or tendon transfer. Complications

Anatomy — the four compartments. Understanding the contents of each compartment determines where each is released and how its ischaemia is detected on passive stretch.

Surface landmarks. The lateral incision runs 2 cm anterior to the fibular shaft, from just distal to the fibular head (staying 5 cm clear of the common peroneal nerve at the neck) to 3-4 cm proximal to the lateral malleolus. The medial incision runs 1-2 cm posterior to the posteromedial tibial border, from the tibial tuberosity to 3-4 cm proximal to the medial malleolus. The posterior tibial neurovascular bundle lies along the posterior tibial surface between the superficial and deep posterior compartments — the reason the deep posterior release is taken hard against bone. Key evidence. Mubarak and Hargens established the pathophysiology and the delta-pressure concept, emphasising that late clinical signs are unreliable. Whitesides provided the experimental basis for the 30 mmHg delta-pressure threshold. Mubarak and Owen described the two-incision technique that remains the standard, and Sheridan and Matsen quantified the morbidity of delayed diagnosis. Court-Brown and McBirnie identified the missed deep posterior compartment as the most common technical failure — the basis for insisting on a full-length medial release confirmed by finger sweep.