The association of leg length and offset reconstruction after total hip arthroplasty with clinical outcomes

Abstract

Background: Restoring native hip anatomy and biomechanics is important to create a well-functioning hip arthroplasty. This study investigated the association of hip offset and leg length after hip arthroplasty with clinical outcomes, including patient reported outcome measures, the Trendelenburg Test and gait analysis. Methods: In 77 patients undergoing primary hip arthroplasty for osteoarthritis (age mean=65 SD=11 years; BMI mean=27 SD=5 kg/m 2), hip offset and leg length discrepancy were measured on anteroposterior radiographs. The Western Ontario & McMaster Universities Osteoarthritis Index, the Trendelenburg Test and gait were assessed preoperatively, and at 3 and 12 months postoperatively. An inertial measurement unit was used to derive biomechanical parameters, including spatiotemporal gait parameters and tilt angles of the pelvis. Relationships between radiographic and functional outcomes were investigated, and subgroups of patients with >15% decreased and increased femoral offset were analysed separately. Findings: patient-reported function scores and clinical tests demonstrated a few significant, weak correlations with radiographic outcomes (Spearman's ρ range =0.26-0.32; p<0.05). Undercorrection of femoral offset was associated with lower patient-reported function scores and with more step irregularity as well as step asymmetry during gait. Postoperative leg length inequality was associated with increased frontal plane tilt angle of the pelvis during the Trendelenburg Test and increased sagittal plane motion of the pelvis during gait. Femoral offset subgroups demonstrated no significant differences for patient-reported function scores and outcomes of the Trendelenburg Test and gait analysis. Interpretation: Reduced hip offset and leg length dicrepancy following hip arthroplasty seem to be marginally associated with worse clinical outcomes.

Geometrical restoration during total hip arthroplasty is related to change in gait pattern - a study based on computed tomography and three-dimensional gait analysis

“…This study has some limitations and strengths. Leg length discrepancy after THA has been discussed as a cause of gait deviations [ 40 ]. In this analysis, we have not included this factor since leg length was measured on CT scans at the pelvis level, not on the total leg.…”

Measuring gait kinematics in patients with severe hip osteoarthritis using wearable sensors

“…Several inertial sensor systems have been described in the last decade [16]. While most studies on OA using inertial sensor systems have focused on knee OA, a few studies performing measurements with inertial sensor systems in patients with hip OA have reported spatiotemporal parameters [6,9,10,17,18], but none of these captured joint kinematics. Among inertial sensor systems, the RehaGait® system has been shown to provide reliable data that are comparable to an instrumented treadmill and camera-based system for measuring spatiotemporal parameters and lower limb kinematics in younger and older healthy subjects as well as in patients with knee OA and lumbar spinal stenosis [19][20][21][22][23].…”

A Workflow Change in Anterior Approach Total Hip Arthroplasty Leads to Improved Accuracy of Biomechanical Reconstruction Without Increased Risk of Complications

“…Innmann et al demonstrated that patients undergoing THA who had accurate hip offset reconstruction and balanced leg length had significantly higher Harris Hip Scores (P ¼ .029) [3]. In addition, there were worse Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores in patients that had undercorrected femoral offset [1,2]. We found that the FF technique significantly improves the accuracy of the hip center of rotation, femoral offset, and leg length.…”

“…The principal study question we sought to address was whether FF workflow would improve biomechanical hip reconstruction in comparison to the traditional AF workflow. Previous studies have reported increased femoral offset to result in leg lengthening, which can lead to a perceived leg length discrepancy and impaired function [1]. In a systematic review, De Fine et al found a statistically significant correlation between femoral offset restoration and reduction of conventional ultrahigh-molecular-weight polyethylene wear [5].…”