Symptomatic femoral head necrosis in patients with rheumatoid arthritis: A retrospective case‐control study.

Objective: We conducted a retrospective case–control study to investigate the risk factors for osteonecrosis of the femoral head (ONFH) in rheumatoid arthritis (RA) patients. Methods: The clinical data of patients diagnosed with RA at Fujian Provincial Hospital from January 2013 to December 2020 were retrospectively collected and evaluated. Twenty‐two patients with ONFH were identified. Eighty‐eight age‐, sex‐, and disease duration‐matched RA patients without symptomatic ONFH were randomly selected as controls in a ratio of 1:4. Logistic regression analysis was used to analyze the risk factors. Results: The anticardiolipin (ACL)‐immunoglobulin G (IgG) concentration, clinical disease activity index, simplified disease activity index, incidence of hyperlipidemia in the case group were higher than those in the control group. Multivariate logistic regression analysis did not find the independent risk factor in ONFH patients with RA. Conclusion: The pathogenesis of ONFH in RA is related to many factors such as ACL IgG, disease activity index, and hyperlipidemia. While, we went to great lengths to explore the relationship between antiphospholipid antibodies and ONFH, but it plays a very small role. [ABSTRACT FROM AUTHOR]