Excellent 10-Year Implant Survivorship Following Primary Total Hip Arthroplasty in Patients Who Have Down Syndrome: A Retrospective Cohort Study.

Abstract

Patients who have Down syndrome (trisomy 21) have unique musculoskeletal and medical characteristics that may influence outcomes after total hip arthroplasty (THA). While early postoperative complications have been described, 10-year implant survivorship in this population remains poorly defined. This study's objective was to evaluate 10-year implant survivorship and mechanical outcomes following primary THA in patients who have Down syndrome and to compare these outcomes to matched patients who did not have Down syndrome. A retrospective cohort study was conducted using a large national database to identify patients who had Down syndrome and underwent a primary THA. Longitudinal outcomes were assessed at predefined intervals up to 10 years postoperatively. Kaplan-Meier analyses were used to estimate survivorship free from revision THA, mechanical failure, and any subsequent hip or pelvic surgery. A 1:1 propensity score-matched cohort of patients who did not have Down syndrome undergoing THA was generated to compare 10-year mechanical outcomes. A total of 255 patients who had Down syndrome were included (mean age 43 years (range, nine to 86)). By 10 years, revision THA occurred in 4.7% of patients. Kaplan-Meier analysis demonstrated 10-year revision-free survival of 94.6%, mechanical failure-free survival of 85.9%, and freedom from any subsequent hip or pelvic surgery of 72.6%. In the propensity-matched analysis (n = 246 per group), there were no statistically significant differences between patients who had and did not have Down syndrome in rates of revision THA (relative risk (RR) 0.92, P = 0.84), mechanical failure (RR 1.30, P = 0.24), or subsequent hip or pelvic surgery (RR 1.16, P = 0.42). Patients who have Down syndrome undergoing primary THA demonstrate excellent implant survivorship at 10 years comparable to matched controls. Trisomy 21 alone does not appear to compromise 10-year implant durability, supporting THA as a durable treatment option in appropriately selected patients.