Compartment Pressure Studies and the Diagnosis of Exertional Compartment Syndrome

Exertional compartment syndrome (ECS) is a condition in which exercise leads to abnormally elevated pressures within a closed muscle compartment, most commonly in the lower leg. This increase in intracompartmental pressure causes pain, tightness, and occasionally neurological symptoms during activity. Compartment pressure studies remain the gold standard investigation, distinguishing ECS from other causes of exertional leg pain, which can cause similar symptoms, including popliteal artery and vein entrapment syndrome, tibial stress injuries, and medial tibial stress syndrome.

Compartment pressure testing involves inserting a needle or catheter into the affected muscle compartment, connected to a pressure transducer (C2Dx STIC Pressure Monitor). Measurements are taken at rest and 1 and 5 minutes post-exercise. The commonly accepted criteria include: a resting pressure ≥15 mmHg, a 1-minute post-exercise pressure ≥30 mmHg, or a 5-minute post-exercise pressure ≥20 mmHg. Exceeding these cut-offs supports the diagnosis of ECS.