Measuring Intracompartmental Pressures in the Lower Leg: Assessing the Use of Unilateral Measurements in Patients with Bilateral Symptoms

Background:The purpose of the present study was to evaluate whether unilateral intracompartmental pressure (ICP) measurements correctly represent the contralateral ICP value in patients suspected to have bilateral chronic exertional compartment syndrome (CECS) in the anterior compartment of the leg.Methods:A retrospective cohort study was performed that included military service members who had been referred to a secondary care department for bilateral anterolateral exercise-related leg pain. The obtained ICP values were utilized to assess 2 possible measurement strategies to perform unilateral ICP measurements: the right-leg strategy (i.e., always testing the right leg) and the most-symptomatic-leg strategy (i.e., always testing the most symptomatic). The diagnostic cutoff value for CECS in this cohort was 35 mmHg in the first minute after provocation. Four outcome categories were created to describe the pressure classification of the second leg if only 1 leg would have been measured: correct (category 1: both values ≥35 mmHg; category 2: both values <35 mmHg) or incorrect (category 3: measured leg, ≥35 mmHg and contralateral leg, <35 mmHg; category 4: measured leg, <35 mmHg and contralateral leg, ≥35 mmHg).Results:A total of 442 patients (884 legs) were included. In 88% of patients, the unilateral value would have correctly diagnosed the other symptomatic leg, whereas in 12% of patients, the contralateral leg would have been diagnosed incorrectly. The right-leg strategy had a slightly smaller proportion of cases in which the contralateral leg would have been incorrectly diagnosed (7% compared with 8% for the most symptomatic leg strategy). In 89% of the 390 patients in categories 1 and 2, the ICP values deviated by >5 mmHg from the 35-mmHg cutoff value compared with 40% of the 52 patients in categories 3 and 4.Conclusions:In military service members with bilateral chronic anterolateral exertional pain, a unilateral ICP measurement seems to be justified, especially among those with pressure values >5 mmHg above or below the diagnostic cutoff value. When a unilateral pressure measurement is within 5 mmHg above or below the cutoff value, a bilateral ICP measurement may be warranted.Level of Evidence:Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.