Unilateral vs. bilateral total knee arthroplasty with 90-day morbidity and mortality: A retrospective cohort study

Background The decision to adopt a unilateral vs. a bilateral approach while performing a total knee arthroplasty (TKA) for a patient with bilateral knee involvement remains a matter of much debate. Previous literature has claimed the supremacy of unilateral surgery in terms of complications where as some evidence supporting no significant difference between the two approaches also exists. In this study, we aim to compare the morbidity and mortality of unilateral with bilateral TKA. Methodology A review of 658 patients who underwent TKA (2005–2015) was carried out. Details of patient characteristics, hospital course and complications occurring within 90 post-operatively were recorded. Data was analyzed using both univariate testing and multivariate regression analysis with a threshold for significance at p < 0.2 and p < 0.05 respectively. Results The study showed that there is no statistically significant difference in the mortality and major complication between unilateral TKA and bilateral TKA. Further analysis revealed that only higher ASA status (3-4) is associated with higher risk of SSI (RR = 3.42,p-value = 0.034). No variables were found to be significant predictors for cardiac complications and UTI. Interestingly, all 3 cases of DVT occurred in bilateral TKR. Conclusions There is no significant difference between unilateral and bilateral TKA in terms of mortality and morbidity except for DVT. This tips the balance in favor of the simultaneous bilateral approach owing to the added benefits of a combined lower cost of surgery, faster recovery, less work absence, single anesthesia session, single hospital admission and fewer follow-ups. Hence, it can be preferred in selected patients with bilateral osteoarthritis.