Please see Bibliography of References for a list of abstracts, manuscripts and posters.
van den Brand J, Nelson T, Verleisdonk E, van der Werken C. The American Orthopaedic Society for Sports Medicine Annual Meeting; June 24-27, 2004; Quebec City, Quebec, Canada.
Patients with chronic exertional compartment syndrome (CECS) have recurrent pain during exercise that usually subsides quickly at rest. Although the aetiology of this syndrome is incompletely understood, the general agreement is that exercise causes abnormal elevation of intramuscular pressure, thus impairing local tissue perfusion and thereby resulting in ischemic pain. History and physical examination may rise the suspicion of CECS but diagnosis is usually confirmed by Intra Compartmental Pressure measurement (ICP) after exercise. Recent studies have shown that Magnetic Resonance Imaging (MRI) and Near Infrared Spectroscopy (NIRS) also have diagnostic ability in CECS
Objective: Although MRI and NIRS have both proven to be feasible diagnostics in smaller studies, this is the first study to seek validation for both methods in a larger series of patients.
Methods: Patients were enrolled if there was a clinical suspicion of CECS and as such a fasciotomy was performed based solely on this suspicion. Prior to fasciotomy ICP, NIRS and MRI data were collected during and after exercise on a treadmill. NIRS and ICP values were recorded in the same manner after fasciotomy. The retrospective proof that the diagnosis CECS had been correct was when the exertional complaints from visit # 1 were gone during exercise at the post-fasciotomy visit.
Results: 50 patients (100 legs) participated in the pre-fasciotomy visit, 3 patients refused fasciotomy, 2 were lost to follow-up. Of the 45 patients (90 legs) that completed the post-fasciotomy visit, the diagnosis CECS was retrospectively confirmed in 42 patients (84 legs) and discarded in 3 patients (6 legs). The sensitivity for ICP (cut-off point ICP > 35 mmHg) found in this study was 77% (67%, 86%, Exact 95% CI), lower than comparator estimates from literature (93%). The sensitivity (previously defined cut-off) found in this study for NIRS was 84% (74%, 91%, Exact 95% CI) which validates the estimate found in the literature (85%). The sensitivity of MRI was found to be comparable to that of ICP and NIRS. However, the associated specificity at a given sensitivity appeared to be lower with MRI.
Conclusion: This study validates the sensitivity of NIRS and provides initial estimates for the sensitivity and specificity of MRI in Chronic Exertional Compartment Syndrome in a larger group of patients. The sensitivity of Near InfraRed Spectroscopy -a non-invasive technique- is clinically equivalent to that of invasive intra compartmental pressure measurements.
Supported by: Hutchinson Technology Inc. BioMeasurement Div., Hutchinson, MN USA