Abstract
Introduction
This study compares the incidence of post-operative complications (within 90 days) following primary total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA).
Methods
2,919 Consecutive patients were retrospectively reviewed over 5 years at three institutions; 2,290 underwent primary TKA and 629 underwent UKA. Simultaneous bilateral procedures and diagnoses other than osteoarthritis were excluded. Regression analysis was performed to isolate the effects of TKA versus UKA on the rate of post-operative complications.
Results
Patients undergoing TKA had a longer length of hospital stay (mean 3.3 vs. 2.0 days, p<0.0001) and were less likely to be discharged to home (odds ratio 5.2, p<0.0001). TKA was associated with a higher risk of undergoing a manipulation (odds ratio 13.0, p<0.0001), requiring a transfusion (odds ratio 8.5, p=0.036), being admitted to an ICU (odds ratio 7.4, p=0.049), and a higher risk of overall complication (11% vs. 4.3%; odds ratio 2.8, p<0.0001) compared to UKA. With the numbers available for this study, there was a trend towards a higher risk of deep infection (0.8% vs. 0.2%; p=0.13) and re-operation for any reason within 90 days (1.4% vs. 0.6%;p=0.064). The risk of complications was higher for TKA even when patients were stratified by Charlson comorbidity index (p=0.008).
Conclusion
The increased risk of peri-operative complications, the longer length of hospitalization and the higher risk of requiring discharge to an extended care facility following TKA should be considered when counseling patients on the choice of TKA versus UKA.
