Healthcare resource utilization and costs for hip dislocation following primary total hip arthroplasty in the medicare population

Aim To estimate 2-year healthcare resource utilization (HCRU) and costs of dislocation following primary total hip arthroplasty (THA). Materials and methods This retrospective evaluation used medical claims from the US Medicare database. Patients were eligible if they were >= 65 years old, underwent a primary elective inpatient THA between 1 January 2010 and 31 December 2016 (index), and had continuous Medicare coverage and enrollment >= 365 days prior to index (baseline). Exclusion criteria were prior THA, concomitant infection, non-Medicare primary payer, or enrolled in Medicare due to end-stage renal disease. One- and 2-year HCRU and costs across all service types and settings of care excluding retail pharmacy were evaluated. Propensity score matching and direct matching adjusted for confounding. Results Among Medicare patients who underwent THA and met inclusion criteria (n = 450,355; mean age similar to 74, and two-thirds female), 7,680 (1.7%) had a hip dislocation. After matching, 4,551 patients without and 4,551 patients with dislocation were selected. Percentage utilization, mean days of service, and claims payments amounts were significantly greater for patients with vs without THA dislocation for variables such as THA hospitalization, home health agency, skilled nursing facility, inpatient rehabilitation facility, other inpatient admission, long-term care hospital, and outpatient care. Findings were consistent for 1- and 2-year follow-up, although differences were more pronounced for 1-year. Per-patient-cost increases with dislocation were $19,590 over 1 year and $24,211 over 2 years. Two-thirds of the cost increase was due to other inpatient admission and the remaining one-third was due to skilled nursing facility, outpatient, inpatient rehabilitation facility, and home health agency costs. Limitations Administrative claims are not collected for research and lack clinical information. Results may not be generalizable to other patients or settings of care. Conclusions This large US retrospective database study demonstrated the substantial HCRU and cost burden of THA dislocation.