Musculoskeletal Surgery in Psoriatic Arthritis: Prevalence and Risk Factors

Despite medical therapy, damage occurs in patients with psoriatic arthritis (PsA) requiring musculoskeletal (MSK) surgery. We aimed to describe MSK surgery in patients with PsA and identify risk factors for undergoing first MSK surgery attributable to PsA.

A single-center cohort identified patients with PsA fulfilling Classification Criteria for Psoriatic Arthritis who had MSK surgery between January 1978 and December 2019 inclusive. Charts were reviewed to confirm surgeries were MSK-related and attributable to PsA. Descriptive statistics determined MSK surgery prevalence and types. Cox proportional hazards models evaluated clinical variables for undergoing first MSK surgery using time-dependent covariates. Using a dataset with 1-to-1 matching on markers of PsA disease severity, a Cox proportional hazards model evaluated the effect of targeted therapies, namely biologics on time to first MSK surgery.

Of 1574 patients, 185 patients had 379 MSK surgeries related to PsA. The total number of damaged joints (hazard ratio [HR] 1.03, P < 0.001), tender/swollen joints (HR 1.04, P = 0.01), presence of nail lesions (HR 2.08, P < 0.01), higher Health Assessment Questionnaire scores (HR 2.01, P < 0.001), elevated erythrocyte sedimentation rate (HR 2.37, P = 0.02), and HLA-B27 positivity (HR 2.22, P = 0.048) were associated with increased risk of surgery, whereas higher Psoriasis Area Severity Index (HR 0.88, P < 0.002) conferred a protective effect in a multivariate model. The effect of biologics did not reach statistical significance.

MSK surgery attributable to PsA is not rare, affecting 11.8% of patients. Markers of cumulative disease activity and damage are associated with a greater risk of requiring surgery.