Effect of Anti-Cyclic Citrullinated Peptide Antibody Serostatus on Outcomes of Silicone Metacarpophalangeal Arthroplasty in Patients With Rheumatoid Arthritis

Background: Anti-cyclic citrullinated peptide antibodies (ACPAs) are associated with more aggressive rheumatoid arthritis disease. We aimed to determine the effect of ACPA serostatus on survival free from revision, all-cause reoperation, and recurrence of coronal plane deformity in patients with rheumatoid arthritis (RA) undergoing silicone metacarpophalangeal (MCP) arthroplasty. Methods: We retrospectively identified silicone MCP arthroplasties performed in patients with RA with known ACPA serostatus from 2000 to 2022. Kaplan-Meier estimates were used to report survival free from revision, all-cause reoperation, and recurrence of coronal plane deviation >10° on postoperative radiographs. We analyzed ACPA serostatus as a risk factor for these endpoints using cluster-robust Cox proportional hazard models, adjusting for patient sex. Results: We included 133 joints in 39 ACPA seropositive patients (9.0 years mean follow-up) and 63 joints in 21 ACPA seronegative patients (5.7 years mean follow-up). Survival free from revision, all-cause reoperation, and recurrent coronal deformity was higher in seropositive patients than in seronegative patients. Anti-cyclic citrullinated peptide antibody seropositivity was significantly associated with lower risk for revision (hazard ratio [HR] = 0.16), all-cause reoperation (HR = 0.20), and recurrent coronal plane deviation >10° (HR = 0.28). Seropositive patients had longer average time to recurrent coronal deviation >10° (3.5 years vs 1.3 years) and less coronal deviation at final radiographic follow-up (15.9° vs 21.5°). Conclusions: Anti-cyclic citrullinated peptide antibody seropositivity is associated with improved silicone MCP implant survivorship and lower risk of recurrent coronal plane deformity in patients with rheumatoid arthritis. More work is needed to better understand the biologic basis of these findings.