Abstract
Objectives:
Bone marrow aspirate concentrate (BMAC) is an autologous orthobiologic agent that has become an emerging area of interest in orthopaedic surgery. Past literature investigating hip arthroscopy outcomes revealed that patients undergoing acetabular labral repair with BMAC augmentation achieve significantly greater improvements in all PROMs at 12- and 24-month follow-up compared to a control cohort. Despite its promise, there remains a paucity of literature on BMAC’s effects on THA-free survivorship, particularly at mid-term follow-up. Furthermore, a widespread concern is the high and variable costs of BMAC augmentation. As the utilization of BMAC in clinical practice continues to rise, it is imperative that sports medicine surgeons ensure that BMAC is both efficacious and cost-effective for patients. The purpose of the present study was to investigate if BMAC is an efficacious and cost-effective adjuvant therapy for preventing mid-term conversion to THA following arthroscopic acetabular labral repair.
Methods:
This was a retrospective cohort study of patients < 50 years old with minimum 2-year follow-up who underwent arthroscopic repair of symptomatic acetabular labral tears. Patients were placed into BMAC or No BMAC cohorts according to whether they received BMAC at the time of repair. Besides BMAC augmentation, there were no differences in surgical technique, indications, or post-operative rehabilitation between cohorts. The primary outcome was quality-adjusted life years (QALYs) gained between BMAC and No BMAC patients, as measured by THA-free survivorship. Kaplan-Meier survival curve analysis was performed to calculate QALYs gained during the study’s time horizon, defined as the longest follow-up timepoint reached by a BMAC patient. Secondary outcomes included the incremental cost-effectiveness ratio (ICER) [Cost of Intervention #1 – Cost of Intervention #2]/[Intervention #1 QALYs – Intervention #2 QALYs], BMAC’s estimated cost to be considered a cost-effective treatment, and independent risk factors for THA-free survivorship. Our institutional OOP price for BMAC is $10,000 – inclusive of all costs associated with harvesting, processing, and application. BMAC was considered cost-effective if its ICER was below a willingness-to-pay (WTP) threshold of $50,000. Sensitivity analyses were performed to estimate BMAC cost-effectiveness at varying prices and QALYs gained.
Results:
358 (BMAC: 124 [34.6%] vs. No BMAC: 234 [65.4%]) patients met inclusion/exclusion criteria (Table 1 and 2). When performing an adjusted Kaplan-Meier survival analysis controlling for sex, labral tear size, and type of FAI, BMAC and No BMAC patients had 100.0% and 88.8% (P = .117) 6.16-year THA-free survival probabilities, respectively. A weighted Cox regression controlling for the same variables suggests that – while not statistically significant – No BMAC patients had a 372% increased risk of converting to THA (HR: 0.21 [0.03-1.69]; P = .144). QALYs were calculated by multiplying the survival probabilities (Figure 1) with the number of patients at risk at each THA conversion (Table 3). BMAC was associated with approximately 0.233 QALYs gained (BMAC: 6.162 vs. No BMAC: 5.929). Given the only procedural differences between cohorts was the $10,000 OOP cost of BMAC augmentation, BMAC had an ICER of $42,935.43 [BMAC Costs ($10,000)]/[QALYs Gained (0.233)]. At a WTP threshold of $50,000, BMAC was cost-effective by an ICER of $7,064.57. A sensitivity analysis controlling for a treatment price of $10,000 indicates that BMAC can be considered cost-effective if it leads to 0.200 QALYs gained. At a price of $3,000 and $5,000, BMAC must improve QALYs by 0.060 and 0.100, respectively, to be considered a cost-effective treatment.
Conclusions:
Given the growing volume of literature investigating the efficacy of hip arthroscopy for joint preservation, identifying adjuvant therapies with the potential to safely prolong the longevity of acetabular labral repairs and delay the progression of joint degeneration is crucial. At an institutional cost of $10,000, BMAC had an ICER of $42,935.43 and was below the WTP threshold by $7,064.57. These findings reveal that BMAC is a cost-effective treatment that has the potential to significantly improve THA-free survivorship following arthroscopic acetabular labral repair.
