19,000 Patient Study Finds Link Between BMI and TKA Reoperation

A new, 19,000 patient study is reporting a positive linear correlation between elevated body mass index (BMI) and reoperations after total knee arthroplasty revision.

The study, “The Effect of Body Mass Index on 30-day Complications After Revision Total Hip and Knee Arthroplasty,” appears in the February 13, 2019 edition of The Journal of Arthroplasty.

The study authors reviewed data from 18,866 patients (9,093 who had revision total hip arthroplasties and 9,773 who had revision total knee arthroplasties. The patient data came from the American College of Surgeons National Surgical Quality Improvement Project database.

The researchers looked at thirty-day rates of readmissions, reoperations, and major and minor complications and then stratified that data according to different weight categories (overweight: BMI >25 and ≤30 kg/m; obese: BMI >30 and ≤40 kg/m; morbidly obese: BMI >40 kg/m) and the normal weight category (BMI > 18.5 and ≤25 kg/m).

Co-author Carlos A. Higuera-Rueda, M.D., director of the Orthopaedic and Rheumatologic Center and department chairman in the Levitetz Department of Orthopaedic Surgery at Cleveland Clinic Florida, explained the correlation he found between BMI and readmission rates to OTW, “There is a clear correlation between elevated BMI and readmission and reoperations, mainly after revision total knee arthroplasty. Likewise, in a univariate analysis the correlation between elevated BMI and revisions after total hip arthroplasty was significant, but after multivariate analysis it was not.”

“This is of a particular interest because surgeons have to be wary of the elevated risk and act on it when possible. Optimize the patients as best as possible and sometimes take some extra measures and stay hypervigilant to prevent such complications. Finally, this has to be taken into consideration for risk stratification for quality metrics analyses and reimbursement.”

Dr. Higuera-Rueda, who is also the Amy and David Krohn Family Distinguished Chair in Orthopaedic Outcomes concluded by telling OTW that the linear correlation he found between elevated BMI and reoperations after total knee arthroplasty revision mean that, “Obese and morbidly obese patients undergoing total knee arthroplasty revisions should be optimized clinically as best as possible and stay under close follow up to detect potential complications early and avoid further surgeries.”