Hypotension associated with methylmethacrylate in partial hip arthroplasties. The role of femoral canal size.

The relationship between a decrease in systolic blood pressure following methylmethacrylate cement insertion in femoral head replacement and femoral canal diameter was investigated in 33 patients. A positive, significant correlation was demonstrated in all patients, especially among the female subgroup. Femoral canal diameters of 21 mm or more were associated with a significantly greater risk of intraoperative hypotension than were diameters of 20 mm or less. This relationship between femoral canal diameter and hypotension appears to be primary and unrelated to the patient's sex or age. In clinical terms, the femoral canal diameter may be easily measured prior to arthroplasty, and a diameter of 21 mm or more indicates an increased risk of hypotension following insertion of cement into the femoral canal.