[Results and complications of knee arthroplasty in patients with obesity].

Introduction: In México, many patients undergoing total knee arthroplasty (TKA) are obese, which has medical and financial consequences. The functional outcomes and the incidence of complications of these patients remain uncertain due to the inconsistency between studies. Objective: To determine the association between obesity, complications and functional results of patients undergoing TKA. Material and methods: Descriptive, cross-sectional, prospective, observational, cohort study in which patients who underwent TKA between September 1, 2021, and August 30, 2022, were studied. Patients were divided by their body mass index (BMI) in < 30kg/m2 and > 30kg/m2 and their demographic characteristics, Oxford Knee Score (OKS), and incidence of complications were compared. Results: Out of the 102 patients, 59 presented a BMI < 30 kg/m2 and 43 a BMI > 30 kg/m2. No difference was found in their postoperative OKS (p = 0.12) and delta OKS (p = 0.07). A significant increase in trans-surgical (p = 0.02) and post-surgical (p = 0.04) complications was found in the group with BMI > 30 kg/m2, presenting a risk 5.03 times higher. Conclusion: A BMI > 30kg/m2 does not affect the functional results after a TKA; however, it is associated with a risk 5.03 times higher of suffering complications during and after surgical intervention.