(I-668) Projected Savings Associated With Lowering the Risk of Total Hip Arthroplasty Revision Due to Dislocation Among Patients With Spinopelvic Pathology

Introduction: Spinopelvic pathology is present in approximately 16% of patients undergoing primary total hip arthroplasty (THA) and is associated with an increased risk of THA revision (rTHA) due to dislocation estimated at 8%. In the United States (US), THA is the most common hospital inpatient operation among Medicare beneficiaries and is ranked fourth when considering all payers. Several strategies can be used to mitigate instability in this population, such as dual-mobility implants, anterior surgical approach, and technology-assistance (for example, pre-surgical planning, computer navigation, and robotic assistance). We aimed to estimate (1) the target population size; (2) economic burden; and (3) 10-year projected savings to the payer of lowering the risk of rTHA due to dislocation in patients with spinopelvic pathology.

Methods: A budget impact analysis was undertaken using published literature; American Academy of Orthopaedic Surgeons American Joint Replacement Registry 2021 Annual Report; Centers for Medicare & Medicaid Services MEDPAR 2019 file; and National (Nationwide) Inpatient Sample (NIS) 2019. Expenditures were inflation-adjusted to 2021 US dollars using the Medical Care component of the Consumer Price Index. Sensitivity analyses were performed.

Results: The target population size in calendar year 2021 was estimated at 5040 (range, 4830-6309) for Medicare (fee-for-service plus Medicare Advantage) and 8003 (range, 7669-10,018) for all-payer. The annual rTHA episode of care (through 90 days) expenditures for Medicare and all-payer were $185 million and $314 million, respectively. Using a 4.14% compound annual growth rate from NIS, the estimated number of applicable rTHA procedures that will be performed from 2022 to 2031 was 63,419 Medicare and 100,697 all-payer. With each 10% reduction in the relative risk of rTHA due to dislocation, Medicare and all-payer could save $233 million and $395 million, respectively, over a 10-year period.

Conclusion : For patients with spinopelvic pathology, a modest reduction in the risk of rTHA due to dislocation could achieve substantial cumulative savings to payers while improving healthcare quality.

How to Improve Patient Care: Adult spinal deformity surgeons should be aware of the increased risk of total hip dislocation with corrective spinal deformity surgery. Potential strategies exist to help minimize this risk.