Is intramuscular pressure a valid diagnostic criterion for chronic exertional compartment syndrome?

OBJECTIVE: To compare the intramuscular pressure (IMP) of the tibialis anterior in healthy persons under several exercise conditions with the IMP diagnostic criteria in use for diagnosing chronic exertional compartment syndrome (CECS). DATA SOURCES: A search of MEDLINE for the period 1966 to March 2010 used the words "intramuscular," "intracompartment," "anterior compartment," and "anterior tibial compartment" linked with "pressure." Reference lists of relevant studies were searched for further articles. STUDY SELECTION: Articles published in English that tested IMP in the tibialis anterior in asymptomatic humans were included if they used no interventions before or during IMP testing. Studies were excluded if data were given as a percentage of IMP or if the data could not be extracted for the tibialis anterior compartment alone. From 515 articles identified, 38 studies met selection criteria DATA EXTRACTION: : Details of the studies included IMP measurement technique, timing of measurement (before, during, and/or after exercise), type and duration of exercise, the number of compartments measured, and participants' ages. Mean or median pressure was recorded in mm Hg. DIAGNOSTIC STANDARD: Criteria for the upper limit of normal pressure under different conditions were the Pedowitz criterion for preexercise IMP (15 mm Hg), the Puranen criterion for IMP during exercise (50 mm Hg), the Styf criterion for relaxation pressure (30-55 mm Hg), and the Pedowitz criteria for mean 1-minute postexercise and 5-minutes postexercise pressures (30 mm Hg and 50 mm Hg, respectively). MAIN RESULTS: Exercise was mostly treadmill walking/running (duration, 1.5-120 min) or ankle dorsiflexion (duration, 10 sec-20 min). Methods of measuring IMP varied from study to study. The lowest mean IMP was identified preexercise at rest (range, 0-20 mm Hg). Five of the 34 studies found a higher mean resting pressure than the criterion (15 mm Hg). Mean pressure during exercise (10 studies, 9 of running, with durations of 5-20 min) varied between 23 mm Hg and 66 mm Hg. Two of these studies found a higher mean peak pressure during exercise than the criterion (50 mm Hg). Mean relaxation IMP, measured in 9 studies, was approximately 25 mm Hg in the 1 treadmill study in which it was measured, whereas studies of dorsiflexion found a range of approximately 5 to 15 mm Hg. All the studies found lower mean relaxation IMP than the criterion (35-50 mm Hg). One of 11 studies and 1 of 10 studies found the mean postexercise IMP after 1 minute and 5 minutes to be above the criteria of 30 mm Hg and 20 mm Hg, respectively. CONCLUSIONS: The limits of anterior tibialis IMP before, during, and after exercise that are used as diagnostic criteria for CECS would include many asymptomatic persons. Intramuscular pressure values were not valid criteria for the presence of the syndrome.