Impact of Systemic Lupus Erythematosus on Short-Term and Long-Term Outcomes in Total Knee Arthroplasty: A National Database Propensity-Matched Cohort Study.

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune condition that elevates perioperative risk in patients undergoing total knee arthroplasty (TKA), including thromboembolic, renal, and infectious complications. Previous studies have been limited by small sample sizes and inadequate cohort matching. This study aims to evaluate 90-day and 2-year complications in SLE patients undergoing TKA using a large, propensity-matched national database.

METHODS

A retrospective cohort analysis was conducted using the TriNetX database. A total of 920 SLE patients undergoing primary TKA were 1:1 matched to non-SLE controls based on demographics and comorbidities. Patients with drug-induced lupus were excluded. Outcomes included medical complications (e.g., DVT, pulmonary embolism, myocardial infarction, renal failure, infection, sepsis, ED visits, readmissions) and mechanical complications (e.g., aseptic loosening, implant failure, revision, dislocation, deep surgical site infection). Kaplan-Meier survival analysis and risk ratio comparisons were done (significance set at P < 0.05).

RESULTS

At 90 days, SLE patients had markedly higher rates of DVT (3.5% vs 2.1%; P = 0.020) and ED visits (11.4% vs 8.2%; P = 0.006). At 2 years, they experienced increased pulmonary embolism (3.9% vs 2.4%; P = 0.021), DVT (8.2% vs 5.1%; P = 0.001), myocardial infarction (3.0% vs 1.8%; P = 0.046), renal failure (9.7% vs 5.2%; P < 0.001), readmissions (6.0% vs 3.6%; P = 0.004), ED visits (30.4% vs 26.9%; P = 0.041), deep SSI (4.9% vs 3.4%; P = 0.044), and dislocation (1.9% vs 1.0%; P = 0.036).

CONCLUSION

SLE patients undergoing TKA demonstrate increased risk for thromboembolic events, renal failure, ED utilization, deep infection, and dislocation.