Minimum 2-Year Outcomes of All-Polyethylene Tibial Components in Patients Who Have Body Mass Index of 35 or Greater.

Abstract

Several studies have reported negative results after total knee arthroplasty (TKA) in obese patients. This study aims to analyze the minimum 2-year outcomes in patients who have a body mass index (BMI) > 35 undergoing cemented TKA using an all-polyethylene tibial component (APTC) at a minimum of 2 years of follow-up. We retrospectively studied 163 obese patients (192 TKAs) who underwent a primary cemented TKA using an APTC comparing the outcomes of 96 TKA patients who had a BMI > 35 to 39.9 (group A) with 96 patients who a TKA and a BMI ≥40 (group B). Median follow-up of groups A and B were 3.8 years and 3.5 years respectively (P = .02). Multiple regression analyses were performed to evaluate independent risk factors associated with complications. Kaplan-Meier survival curves were estimated, defining failure as the need for any further femoral or tibial revision surgery with implant removal, irrespective of the reason. There was no significant difference at the latest follow-up patient-reported outcomes between both groups. Survivorship, as defined by revision for any reason, was 99% for group A and 99% for group B (P = 1.00). There was 1 aseptic tibial failure in group A, and 1 septic failure in group B. Multiple regression analyses showed no significant associations between age (odds ratio [OR] = 1.00; P = .98; 95% confidence interval (CI) = 0.93 to 1.08), sex (OR = 1.38; P = .70; 95% CI = 0.26 to 7.25), BMI (OR = 1.00; P = .95; 95% CI = 0.87 to 1.16), and complication rate. At a median 3.7-year follow-up, the use of an APTC provided excellent outcomes and survivorship in patients who had Class 2 and Class 3 obesity. Level III, therapeutic study.