Outcomes of Total Hip Arthroplasty in Seronegative Spondyloarthropathies: A Propensity-Matched Cohort Analysis

Background: Total hip arthroplasty (THA) is a common surgical intervention for patients who have seronegative spondyloarthropathies (SpA). However, there is a paucity of literature addressing the outcomes of THA specifically in SpA patients. This study aimed to investigate both the short-term and long-term systemic and orthopaedic outcomes of THA in SpA patients as a whole, as well as within the individual subtypes of SpA.

Methods: This retrospective cohort study used a federated health research network, identifying 3,074 SpA patients who underwent THA between 2005 and 2022. Propensity score matching was used to compare SpA and non-SpA patients, balancing baseline characteristics. Short-term (30 days, 180 days, and 1 year) and long-term (5 years) postoperative complications were analyzed. The outcomes included systemic and joint complications. Chi-square analyses were done to compare outcomes across categorical data.

Results: The SpA patients had increased rates of revision THA, prosthetic dislocation, periprosthetic joint infection, and aseptic loosening at various postoperative intervals. Surgical site infections and myocardial infarctions were more frequent at 1 month, 6 months, and 1 year. Additionally, SpA patients exhibited a higher incidence of deep vein thrombosis at 6 months and 1 year. Subtype analysis revealed that ankylosing spondylitis patients were more likely to have revision surgery and prosthetic dislocation, while psoriatic arthritis patients had a lower risk of hip dislocation and femur fractures.

Conclusions: The SpA patients undergoing THA are at greater risk for systemic and orthopaedic complications compared to non-SpA patients. The increased incidence of infections, thromboembolic events, and prosthetic issues highlights the need for careful preoperative assessment and postoperative management.