Early complications of revision total knee arthroplasty in morbidly obese patients.

INTRODUCTION: Morbid obesity is a known risk factor for complications and failure following primary total knee arthroplasty. Complications following revision total knee arthroplasty (rTKA) in the morbidly obese (BMI > 40) have not been well described. A retrospective cohort study was designed to investigate the early complications of rTKA in morbidly obese patients. METHODS: Revision TKA procedures were performed between January 2009 and December 2012 at a single institution. Comparisons were made between patients with a normal BMI (18.5-25) and patients with morbid obesity (BMI > 40). RESULTS: Thirty-three of 141 morbidly obese patients (23.4%) had a complication compared to 10 of 96 patients with a BMI 18.5-25 (10.4%) (p = 0.011). Morbidly obese patients were younger (69.3 vs. 61.4 years, p < 0.0001), and their most frequent complication in comparison with patients with normal BMI was wound healing problems (p = 0.01). CONCLUSION: Morbidly obese patients are at a significantly increased rate of early complications following rTKA compared to a normal weight cohort, especially with regard to wound complications. The morbidly obese group was significantly younger at the time of rTKA. In addition, this study highlights the importance of risk stratification for morbidly obese patients undergoing rTKA.