Obesity does not necessarily affect the accuracy of acetabular cup implantation in total hip replacement

Postoperative radiographs of 111 patients who had undergone cemented total hip replacement performed or supervised by a single surgeon were analysed. All surgeries were performed via an anterolateral approach with patients in the lateral position. Patients were stratified according to Body Mass Index (BMI) into three groups (healthy, overweight and obese) and acetabular cup angles were measured. Mean values for cup abduction angle were similar for all three groups (44.5 degrees, 46.8 degrees, 44.0 degrees respectively, p = 0.335). Furthermore there were no differences in mean cup anteversion between groups (11.6 degrees, 12.2 degrees and 10.7 degrees respectively, p = 0.665). We conclude that obesity does not necessarily influence the accuracy of cup positioning in total hip replacement.