Pressures in the tibialis anterior muscle were recorded at rest and during exercise with transducer-tipped
catheters in 12 volunteers while they were supine or standing. The recordings were repeated with venous stasis created by an inflated
tourniquet cuff on the thigh.
Catheters were placed at 3 different sites in the muscle:
catheter I adjacent to the deep surface of the fascia over the anterior compartment;
catheter II between the fascia and the central tendon; and
catheter III deep in the muscle close to the interosseous membrane. In both the supine and standing positions the intramuscular pressure at rest and the muscle relaxation pressure during exercise, obtained by
catheter II, were greater than the corresponding pressures measured by the superficially located
catheter I in the normal as well as in the volume loaded limb. The same conditions for pressure measurement consistently revealed lower pressures recorded by
catheter III compared to II, but the difference was not significant. Our results indicate that intramuscular pressure increases centripetally, as the centrally lying tendon is approached. We conclude that pressure measurements for diagnosis of acute and chronic
compartment syndromes and in ergonomic studies should be based on recordings from a standard location of the
catheter within the muscle and a standard posture of the subject.