Insulin Dependence Increases the Risk of Failure After Total Knee Arthroplasty in Morbidly Obese Patients

The aims of this study were to compare the outcomes between nondiabetic (n = 1284), type II diabetic (n = 530), and insulin-dependent type II diabetic (n = 164) morbidly obese (body mass index ≥ 40 kg/m2) patients undergoing primary total knee arthroplasty at 6-year follow-up. Patients with type II diabetes mellitus (DM) had similar outcomes when compared with non-DM patients. However, patients with insulin dependence had an increased risk of reoperation (hazard ratio [HR], 1.8; P = .005), revision (HR, 2; P = .02), and periprosthetic joint infection (HR, 2.1; P = .03), as well as decreased 10-year implant survivorship (84% vs 92%; P = .01) when compared to non-DM patients. Prospective studies should further evaluate outcomes and optimization measures within this population. Level of evidence: Level III-prognostic study.