Timing of Renal Transplant Prior to Total Knee Arthroplasty Impacts 90-Day Post-Operative Outcomes.

INTRODUCTION: Renal transplant (RT) patients are at increased risk for complications after total knee arthroplasty (TKA); however, it is unknown if the time from RT to TKA influences such risks. This study evaluated RT patients undergoing primary TKA at various time intervals after transplant. We hypothesized that increased time between RT and TKA would decrease the risk of complications after TKA.

METHODS: There were 499 RT patients in a national database undergoing subsequent primary TKA from 2010 to 2020. Patients were stratified by intervals of less than one year, between 1 to 2 years, and greater than two years from RT to TKA. Medical complications up to 90 days, readmissions, and two-year revisions were compared via univariable and multivariable analyses.

RESULTS: Patients who underwent TKA less than one year after RT were associated with higher 90-day medical complications when compared to those who underwent TKA 1 to 2 years after RT (odds ratio (OR) 0.4, confidence interval (CI) 0.2 to 0.8, P = 0.01) and greater than two years (OR 0.3, CI 0.2 to 0.7, P < 0.01) after RT. Acute kidney injury and blood transfusion were the most common complications. The TKAs performed two years after RT were less likely to have 90-day readmissions when compared to TKAs performed less than one year after RT (OR 0.4, CI: 0.2 to 0.9, P < 0.01). However, time from RT to TKA did not increase the risk of revision at two years (P > 0.30).

CONCLUSION: Patients undergoing TKA within one-year of RT have an increased risk of 90-day postoperative medical complications and readmissions, but the time interval from RT does not appear to affect revision risk. These findings suggest waiting one year after RT before proceeding with TKA may be advantageous.