Subcutaneous and intramuscular pressures in the post-phlebitic limb.

The mechanisms of pain in patients with chronic iliac vein obstruction and venous claudication is not fully understood. Ten patients with severe to moderate unilateral post-thrombotic syndrome with chronic iliac vein obstruction were studied. Subcutaneous tissue pressures and intramuscular pressures were measured using the slit-catheter technique in both legs, at rest and during exercise. The subcutaneous tissue pressure was higher, but not significantly higher, in the leg with iliac vein obstruction, +2 (-2 to +10) mmHg, than in the contralateral healthy legs, 0 (-4 to +4) mmHg in supine position at rest. During exercise in the standing position the subcutaneous tissue pressure rose significantly (p less than 0.01) in the diseased leg to 9 (+4 to +15) mmHg, while no such increase was seen in the control limb, 0 (-4 to +4) versus -1 (-5 to +4) mmHg. The intramuscular pressures were significantly higher (p less than 0.01) in the leg with iliac vein obstruction 26 (15 to 42) mmHg, than in the control leg, 11 (1 to 15) mmHg at rest in supine position as well as during exercise in standing position, 64 (35 to 82) mmHg and 26 (10 to 36) mmHg, respectively.