The Effect of Obesity on Simultaneous Bilateral Knee Arthroplasty Surgery

The aim of this study was to evaluate the effect of obesity on clinical outcomes and complications in patients undergoing simultaneous bilateral total knee arthroplasty (SBTKA) based on body mass index criteria.

Between 2013 and 2020, SBTKA was performed on 795 patients with a mean age of 72 years. After applying exclusion criteria, 776 patients were included in the study. Patients, followed up for an average of 48 months, were categorized by body mass index into two groups: <30 kg/m2 (group I: nonobese) and 30 to 39.9 kg/m2 (group II: obese). Group I consisted of 347 patients while group II included 429 patients. The groups were compared using univariate and multivariate logistic regression analyses for parameters such as length of hospital stay, mobilization time, surgical time, clinical and functional outcomes, prosthetic infection, aseptic loosening, early complications, and wound healing problems.

Statistically, there was no significant difference between the groups regarding the incidence of deep vein thrombosis, acute kidney injury, or pulmonary embolism. Statistical analysis revealed that the risk of complications such as aseptic loosening, septic loosening, and medial retinaculum detachment was lower in group I compared with group II. However, univariate and multivariate logistic regression analyses demonstrated no significant differences in overall complications or clinical outcomes between the groups. The only parameters showing significant differences were surgical time, mobilization time, and length of hospital stay.

We conclude that, when existing comorbidities are taken into account, SBTKA can be safely and successfully performed in obese patients, comparable to nonobese patients.