• INTRODUCTION
    • Total hip arthroplasty (THA) is reaching a broader spectrum of younger patients who struggle with incapacitating hip disease. This study aimed to explore national bearing surface trends for young THA recipients. Specifically, we evaluated bearing surface utilization, patient demographics, and hospital demographics in 20- to 50-year-old THA recipients in the United States from 2009 to 2016.
  • MATERIALS AND METHODS
    • The National Inpatient Sample database was queried for patients aged 20 to 50 who underwent primary THA from 2009-2016 (n=279,190). Patients were grouped according to bearing surface type (metal-on-polyethylene [MOP], metal-on-metal [MOM], ceramic-on-ceramic [COC], and ceramic-on-polyethylene [COP]). Demographics included sex, age, race, obesity status, age-adjusted Charlson Comorbidity Index (CCI), primary payer, median household income, region, and teaching status. Chi-square analyses were employed for categorical variables, while independent t-tests were utilized for continuous variables.
  • RESULTS
    • The incidence of THA for patients aged 20 to 50 increased slightly from 33,003 in 2009 to 33,545 in 2016 (p<0.001). Overall, bearing surface type was reported in 46.8% (n=127,876) of THAs. Of the THAs with bearing surface codes, the use of MOP (29.6 to 18.7%) and MOM (39.6 to 4.4%) decreased, while COC (9.0 to 14.3%) and COP (21.8 to 62.6%) utilization increased (p<0.001 for all). Those receiving COC implants had the youngest average age (42 years) (p<0.001). Females were more likely to receive COC (44.2%) or COP (43.6%) implants (p<0.001). Obese individuals were more likely to receive MOP (21.3%) or COP (21.2%) (p<0.001).
  • CONCLUSION
    • Over an 8-year period, considerable shifts in bearing surface trends have occurred across the United States among 20 to 50-year-old patients. Advantages of ceramic femoral heads, along with increased acceptance of highly cross-linked polyethylene, appear to be reasons for the selection of COP over other bearing surfaces.