Clinical significance of leg-length inequality after total hip arthroplasty

Sixty-eight patients were interviewed and examined after total hip arthroplasty (THA) to determine the clinical consequences (patient satisfaction, shoe lift use, gait abnormalities, etc) of leg-length inequality. No patient met clinical or radiographic criteria for revision THA. Minimum follow-up was 2 years, and average follow-up was 6.6 years (range, 2 to 20.5 years). A questionnaire, with specific questions about leg-length inequality, was completed by each patient. Leg-length inequality was determined by orthoroentgenography and compared with clinical measurements of leg length. The average inequality in this series of patients was 9.7 mm. A significant number (32%) of patients were aware of this inequality; the average leg-length inequality in this group was 14.9 mm. More than half of these patients were disturbed by the inequality. The magnitude of leg-length inequality closely correlated with awareness of the inequality, abnormal gait, use of ambulatory assistive devices, the need for a shoe lift, prior leg-length inequality, and revision THA. Clinical measures of leg-length inequality correlated poorly with values determined orthoroentgenographically. The high rate of dissatisfaction among patients with a leg-length inequality and the untoward results associated with this inequality indicate that surgeons performing THA should familiarize themselves with a reliable method for equalizing leg lengths intraoperatively.