A large database study of hospitalization charges and follow-up re-admissions in US lumbar fusion surgeries using a cellular bone allograft (CBA) versus recombinant human bone morphogenetic protein-2 (rhBMP-2)

Abstract

Background The objective of this study was to retrospectively compare initial procedure and 12-month follow-up hospitalization charges and resource utilization (lengths of stay; LOS) for lumbar fusion surgeries using either recombinant human bone morphogenetic protein-2 (rhBMP-2) or a cellular bone allograft comprised of viable lineage-committed bone cells (V-CBA) via a large US healthcare system database. Potentially relevant re-admissions during the follow-up period were also assessed. Methods A total of 16,172 patients underwent lumbar fusion surgery using V-CBA or rhBMP-2, of whom 3503 (21.66%) patients had follow-up re-admission data. Initial patient, procedure, and hospital characteristics were assessed to determine confounding factors. Multivariate regression modeling compared differences in hospitalization charges (in 2018 US dollars) and LOS (in days) between the groups, as well as incidences of potentially relevant re-admissions during the 12-month follow-up period. Results The adjusted mean initial procedure and 12-month follow-up hospital charges were significantly lower in the V-CBA group versus the rhBMP-2 group ($109,061 and $108,315 versus $160,191 and $130,406, respectively; P < 0.0001 for both comparisons). This disparity remained in an ad hoc comparison of charges for initial single-level treatments only (V-CBA = $103,064, rhBMP-2 = $149,620; P < 0.0001). The adjusted mean initial LOS were significantly lower in the V-CBA group (3.77 days) versus the rhBMP-2 group (3.88 days; P < 0.0001), but significantly higher for the cumulative follow-up hospitalizations in the 12-month follow-up period (7.87 versus 7.46 days, respectively; P < 0.0001). Differences in rates of follow-up re-admissions aligned with comorbidities at the initial procedure. Subsequent lumbar fusion rates were comparable, but significantly lower for V-CBA patients who had undergone single-level treatments only, in spite of V-CBA patients having significantly higher rates of initial comorbidities that could negatively impact clinical outcomes. Conclusions The results of this study indicate that use of V-CBA for lumbar fusion surgeries performed in the US may result in substantially lower overall hospitalization charges versus rhBMP-2, with both exhibiting similar rates of 12-month re-admissions and subsequent lumbar fusion procedures.

A 24-month retrospective update: follow-up hospitalization charges and readmissions in US lumbar fusion surgeries using a cellular bone allograft (CBA) versus recombinant human bone morphogenetic protein-2 (rhBMP-2)

“…Previously, we reported [10] that use of V-CBA was associated with $51,130 less in mean hospital charges for initial lumbar fusion procedures versus rhBMP-2, and $22,091 less in mean 12-month follow-up hospitalization charges. Yet, these 12-month data showed that patients receiving either graft exhibited similar rates of subsequent lumbar fusion procedures and potentially-relevant hospital readmissions [10]. The primary objective of this study was to build upon these findings by extending the comparison to 24-months of follow-up hospitalization charges and resource utilization.…”

“…As an alternative, recombinant human bone morphogenetic protein-2 with a bovine collagen sponge scaffold (rhBMP-2; marketed as Infuse ® by Medtronic Inc., Memphis TN), has been widely utilized with demonstrated osteoinductive efficacy in spinal fusion, despite US FDA approval for the spine being limited to single-level lumbar fusions within approved interbody cages and multiple reports of serious complications [5][6][7]. However, rhBMP-2 remains relatively expensive [8][9][10] and reduction of economic burden has become an increasingly high priority in modern healthcare systems [5].…”

“…While most CBAs rely on viable cryopreserved mesenchymal stem cells for their osteogenic component, a more recent advanced CBA (V-CBA; marketed as ViviGen ® by LifeNet Health ® , Virginia Beach VA) is comprised of lineage-committed bone-forming cells, which may be more conducive to effect bone fusion [13][14][15]. V-CBA can be used for homologous repair of any bone defect throughout the body [16] and reported clinical outcomes of spinal fusions using V-CBA have thus far been positive [10,12].…”

Allografts and Spinal Fusion

“…In a well-established rat model, fusion is assessed by manual palpation of a bony mass 6 to 8 weeks after implantation of DBM-based or CBM-based graft placed between the transverse processes during a posterolateral fusion procedure. 33,34,76 Using this model, Bhamb et al 33 reported at 8 weeks a 0 of 16 fusion rate in rats implanted with CBM Osteocel Plus Pro (NuVasive) compared with 88% to 100% fusion rate after noncellular human DBM-based products were implanted (Acell Evo3, DBX Mix, DBX Strip, Grafton Crunch, Grafton Flex, and Grafton Matrix), and 13% (2 of 16) were manually fused when implanted with syngeneic bone graft. Lin et al 76 The findings of these studies highlight the variability among CBM commercial products and potentially among production lots.…”

“…33,34,76 Using this model, Bhamb et al 33 reported at 8 weeks a 0 of 16 fusion rate in rats implanted with CBM Osteocel Plus Pro (NuVasive) compared with 88% to 100% fusion rate after noncellular human DBM-based products were implanted (Acell Evo3, DBX Mix, DBX Strip, Grafton Crunch, Grafton Flex, and Grafton Matrix), and 13% (2 of 16) were manually fused when implanted with syngeneic bone graft. Lin et al 76 The findings of these studies highlight the variability among CBM commercial products and potentially among production lots. 32 Yet, interestingly, there are common observations across these studies: Syngeneic bone graft, a proxy for ICBG in this model, containing some live cells yielded low fused rates (13%, 33%, and 40%) across the studies, whereas the Osteocel Plus preparations consistently yielded almost no sites fused (0%, 0%, and 7%).…”