Longitudinal Outcomes of Total Hip Arthroplasty in Developmental Dysplasia of the Hip: A National Database Propensity-Matched Analysis.

Abstract

Developmental dysplasia of the hip (DDH) complicates total hip arthroplasty (THA) due to altered anatomy and biomechanics, increasing surgical complexity and postoperative risks. Although its effect on THA outcomes has been studied, data on long-term implant performance and revision surgery rates remain limited. This study uses a large, propensity-matched cohort to assess 90-day medical complications and 2-year mechanical outcomes in patients with DDH undergoing THA, addressing critical gaps in the literature. A retrospective cohort study using the TriNetX Research Network analyzed data from 104 healthcare organizations. Patients with DDH undergoing THA (n = 5908) were matched with control subjects (n = 5908) based on age, sex, BMI, and comorbidities. Outcomes included 90-day medical (infection, sepsis, thromboembolism, myocardial infarction, and mortality) and 2-year mechanical complications (reoperations and implant failure). Analyses included risk differences (RD), risk ratios (RR), Kaplan-Meier survival, and P-values. No notable differences were observed in 90-day medical complications between DDH and control cohorts. However, patients with DDH demonstrated significantly higher risks of 2-year mechanical complications: revision surgeries: RD: 0.011 (95% CI, 0.005 to 0.017, P = 0.000); RR: 1.492 (95% CI, 1.199 to 1.858). Implant failure: RD: 0.012 (95% CI, 0.005 to 0.018, P = 0.001); RR: 1.394 (95% CI, 1.152 to 1.687). Kaplan-Meier survival analysis further confirmed significantly lower revision surgery-free survival (log-rank P = 0.001) and implant survival (log-rank P = 0.002) in patients with DDH compared with control subjects. DDH increases 2-year mechanical complications post-THA, emphasizing the need for tailored surgical planning. The absence of increased 90-day medical complications supports perioperative safety. Future research should optimize long-term outcomes through innovations in implant design and surgical techniques.