Leg Length Discrepancy after Total Hip Replacement

Leg length differential in 110 patients with unilateral hip arthritis was measured on supine AP radiographs before and after hip arthroplasty, and compared with subjective sensation of leg length discrepancy at that time. Eight percent of limbs were of equal length, 60% were within 0.5 cm. and 9% demonstrated a discrepancy greater than 1 cm. Shortening was tolerated better than lengthening. No patient with true shortening of less than 6 mm or lengthening of less than 4 mm perceived discrepancy. Shortening of over 10 mm and lengthening of over 6 mm was perceived universally. Shortening of between 6 mm and 10 mm was perceived by 55% of patients, and lengthening between 4 mm and 6 mm by 26%.