Intraosseous pressure in the femoral head and greater trochanter before and 1-3 years after osteotomy for osteoarthritis of the hip joint.

To elucidate the long-term effect of osteotomy upon the intraosseous pressure in osteoarthritis of the hip, pressure measurements in the femoral head and greater trochanter were performed in 22 patients before intertrochanteric osteotomy and 11.5-33.5 months later, on the occasion of removing the osteosynthesis material after the osteotomy had healed. Preoperatively the mean pressure in the femoral head was higher (35.0 mmHg) than in the greater trochanter (23.4 mmHg). At follow-up the mean pressure in the femoral head had fallen, but not significantly (0.10 less than P less than 0.20). A significant reduction in pressure (0.001 less than P less than 0.005) was found in 10 patients in whom the primary pressure was high (exceeding 35 mmHg) and in 16 patients seen at follow-up less than two years after the osteotomy (0.01 less than P less than 0.02), whereas with a longer observation period there was a tendency towards an increasing pressure. The trochanteric pressures accompanied the pressures in the femoral head, but without significant changes. No close correlation was found between intraosseous pressure and pain at rest. The operation had a good clinical effect, especially upon the pain at rest. A reduction in intraosseous hypertension may be a contributory cause, but the tendency to another increase in pressure after a long observation period indicates the possibility of a subsequent recurrence.