Work

The Effect of Obesity on Prosthesis Positioning in Total Hip Arthroplasty Through the Posterolateral Approach: A Retrospective Study on 614 Total Hip Arthroplasties

Year: 2025

Type: article

Abstract: Background In total hip arthroplasty (THA), orientation of prosthesis components is important regarding outcome. Obesity has been related to poorer placement of the acetabular component. Larger studies investigating the detailed impact of body mass index (BMI) > 35 kg/m 2 on prosthesis component positioning are lacking. The aim of this study was to investigate the effect of BMI > 35 kg/m 2 on prosthesis positioning in hip osteoarthritis patients undergoing primary THA. Methods This retrospective observational study analyzed 614 THAs performed between 2015 and 2022 categorized in an obese and a normal-weight group. Cup positioning and orientation, stem alignment, and leg length discrepancy were assessed using preoperative and postoperative radiographs. Adjusted multiple linear regression models were applied to detect statistically significant differences in cup and stem orientation and placement between the 2 groups. Results A total of 614 hips were analyzed, including 156 from patients with a BMI > 35 kg/m 2 and 458 from patients with a normal BMI. The acetabular components in the obese group exhibited significantly lower anteversion angles (16.5° vs 19.7°) and greater inclination angles (42.9° vs 45.6°) compared to the normal-weight group. Conclusions The influence of obesity on inclination and anteversion angles should be considered during THA to prevent substantial malpositioning of prosthesis components. Further research is required to determine the clinical implications of these variances in prosthesis component placement between normal-weight and obese patients, particularly given the ongoing debate regarding the optimal ‘safe zone' for acetabular component positioning and orientation.

Source: Arthroplasty Today

DOI: 10.1016/j.artd.2025.101696

Authors: Hans Christian S. Vistisen, Mads J. Rex, Mogens Laursen, Thomas Jakobsen

Institution: Aalborg University Hospital

Language: English

Topic: Orthopaedic implants and arthroplasty

Subfield: Surgery

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,500