Efficacy, Cost, and Complications of Demineralized Bone Matrix in Instrumented Lumbar Fusion: Comparison With rhBMP-2

Abstract

Study Design: Retrospective cohort study. Objectives: To evaluate demineralized bone matrix as an adjunct for instrumented lumbar spine fusion compared with recombinant human bone morphogenetic protein–2 (rhBMP-2). Methods: Clinical and radiographic review was performed of 43 patients with degenerative spine disease treated with posterolateral spinal fusion with or without posterior or transforaminal lumbar interbody fusion. Final analysis included sixteen patients treated with demineralized bone matrix (DBM; Accell Evo3, SeaSpine) compared with a retrospective matched group of 21 patients treated with rhBMP-2 (rhBMP-2, Infuse, Medtronic). All patients were followed for 24 months. Fusion was evaluated by computed tomography and/or x-ray. Clinical outcomes included visual analogue scale (VAS), Oswestry Disability Index (ODI), and Short Form 12 (SF-12). Results: Overall fusion rate, including posterolateral and/or interbody fusion, was 100% for both groups, though the fusion rates in the posterolateral space alone were 93.5% and 100% for the DBM and rhBMP-2 groups, respectively. Clinical outcomes were similar between groups, with the DBM group showing greater improvement in ODI. The rhBMP-2 group showed higher rates of radiographic complications with 7 of 21 patients (33.3%) demonstrating either adjacent level fusion or ectopic bone formation, compared with zero in the DBM group. Average biologic cost per level was $1522 for DBM and $3505 for rhBMP-2. Conclusions: DBM and rhBMP-2 demonstrated similar radiographic and clinical outcomes in instrumented lumbar fusions. rhBMP-2 was associated with higher rates of radiographic complications and significantly higher costs.