Pressure-controlled ultrasound is a novel non-invasive technique for detecting anterior chronic exertional compartment syndrome.

Objectives: Chronic exertional compartment syndrome (CECS) is traditionally confirmed by intracompartmental pressure (ICP) measurement, but this test has been criticised. The aim of this study was to investigate whether leg muscle compartment compressibility using pressure-controlled ultrasound has diagnostic potential in anterior leg compartment CECS (ant-CECS). We hypothesised that, following exercise, patients with ant-CECS would demonstrate lower compartment compressibility and greater compartment thickness compared with controls. Methods: Patients with bilateral ant-CECS failing conservative treatment underwent ICP measurements of one leg and compartment compressibility analysis of the contralateral leg before and after a standardised treadmill test. Compartment compressibility was calculated as the relative reduction in distance between a superficial and deep muscle landmark at 10 mm Hg and 80 mm Hg external ultrasound probe pressure. The primary outcome was the difference in compressibility between patients with ant-CECS and healthy controls. Results: Between February 2023 and April 2025, 635 ultrasound measurements were analysed in 36 patients (23 males, age 28 (SD 10 years)) and 35 controls (14 males, age 38 (SD 15 years)). Patients had at least one of three Pedowitz criteria confirming ant-CECS (ICP ≥15 mm Hg at rest, or ≥30 mm Hg or ≥20 mm Hg 1 and 5 min after treadmill, respectively). Compressibility in ant-CECS was lower at rest and at each time point after treadmill testing compared with controls (p<0.01). In males, a 7.8% compressibility cut-off value measured 5 min post-exercise yielded a positive predictive value of 94%. Conclusion: Pressure-controlled ultrasound is a novel non-invasive technique for detecting leg anterior chronic exertional compartment syndrome with promising diagnostic accuracy, particularly in males. Trial registration number: NCT05720182.