Elevated Risk of Periprosthetic Joint Infection and Revision in Patients Who Have Psoriasis after Total Knee Arthroplasty: A Propensity-Matched Cohort Analysis.
BACKGROUND Total knee arthroplasty (TKA) is a highly successful procedure for managing arthritis, though complications such as periprosthetic joint infection (PJI), periprosthetic fracture (PPFx), and mechanical loosening can occur. Psoriasis has been associated with an increased likelihood of requiring TKA. METHODS A large, multi-institutional electronic health records database was utilized to identify patients who had an active diagnosis of psoriasis within three months prior to undergoing TKA. Using propensity-score matching, these patients were matched 1:1 with a cohort of patients who did not have psoriasis prior to TKA. Outcomes assessed at 90-days postoperatively included wound disruption, infection, pulmonary embolism, deep vein thrombosis (DVT) of the lower extremity, acute kidney injury (AKI), and readmissions. The two-year outcomes included PPFx, PJI, mechanical loosening, and revision total knee arthroplasty (rTKA). A total of 156,015 patients undergoing primary TKA were identified. Ultimately, 4,191 patients who had psoriasis were propensity matched to 4,191 controls. RESULTS Patients who had psoriasis were at a greater risk of developing DVT (RR [relative risk]: 1.5; CI [confidence interval]: 1.1 to 2.0) and wound disruption (RR: 1.7; CI: 1.1 to 2.6) at 90 days postoperatively. At two years postoperatively, patients who had psoriasis had higher rates of PJI (RR: 1.5; CI: 1.1 to 2.1) and rTKA (RR: 1.5, CI: 1.1 to 2.0). CONCLUSIONS Patients who have psoriasis undergoing TKA have a higher risk of wound disruption and DVT of the lower extremity within 90 days, and of PJI and rTKA within two years. The elevated risk of these complications warrants particular attention from orthopaedic surgeons and their patients who have psoriasis in both preoperative shared decision-making and close follow-up care.