The difference between actual and prescribed weight bearing of total hip patients with a trochanteric osteotomy: Long-term vertical force measurements inside and outside the hospital

Objective: To determine whether patients load the operated leg at a prescribed weight-bearing target load during postoperative recovery. Design: A descriptive prospective study. Setting: Orthopedic clinic and patients' homes. Participants: Fifty patients who had undergone total hip arthroplasty (THA) with trochanteric osteotomy. Intervention: Patients were verbally instructed by a physical therapist to perform partial weight bearing at a 10% body weight (BW) target load (n=33) or at a 50% BW target load (n= 17). Main Outcome Measures: Mean peak load (%BW) and percentage of patients and mean percentage of steps below, equal to, and above the target load. Weight bearing was measured when patients walked with (condition 1) and without (condition 2) a physical therapist in the hospital and walked at home (condition 3). Results: The mean peak load was significantly higher than the target in the 10% BW group for all 3 conditions (condition 1, 19.2% BW; condition 2, 20.0% BW; condition 3, 26.8% BW). In the 50% BW group, the mean peak load was significantly lower than the target in conditions 1 (28. 1% BW) and 2 (32.5% BW). No significant difference in weight bearing was found when walking with or without a physical therapist (change in 10% BW -0.1% BW; change in 50% BW, -3.17% BW). At home, the mean peak load was significantly larger compared with walking without a physical therapist in the hospital (change in 10% BW, -7.0% BW; change in 50% BW, -11.5% BW). Conclusions: Partial weight bearing at a specific target load was not achieved by patients with a THA when given verbal instructions. Especially when using a low target load and when walking at home with no supervision of a physical therapist, patients loaded the operated leg higher and more frequently above the target load. Other training methods (eg, biofeedback) have to be evaluated to use as training tools for partial weight bearing at specific target loads.