Does Recombinant Human Bone Morphogenetic Protein-2 Use in Adult Spinal Deformity Increase Complications and Are Complications Associated With Location of rhBMP-2 Use? A Prospective, Multicenter Study of 279 Consecutive Patients

Study Design. Multicenter, prospective analysis of consecutive patients with adult spinal deformity (ASD). Objective. Evaluate complications associated with recombinant human bone morphogenetic protein-2 (rhBMP-2) use in ASD. Summary of Background Data. Off-label rhBMP-2 use is common; however, underreporting of rhBMP-2 associated complications has been recently scrutinized. Methods. Patients with ASD consecutively enrolled into a prospective, multicenter database were evaluated for type and timing of acute perioperative complications. Inclusion criteria: age 18 years and older, ASD, spinal arthrodesis of more than 4 levels, and 3 or more months of follow-up. Patients were divided into those receiving rhBMP-2 (BMP) or no rhBMP-2 (NOBMP). BMP divided into location of use: posterior (PBMP), interbody (IBMP), and interbody + posterior spine (I + PBMP). Correlations between acute perioperative complications and rhBMP-2 use including total dose, dose/level, and location of use were evaluated. Results. A total of 279 patients (mean age: 57 yr; mean spinal levels fused: 12.0; and mean follow-up: 28.8 mo) met inclusion criteria. BMP (n = 172; average posterior dose = 2.5 mg/level, average interbody dose = 5 mg/level) had similar age, smoking history, previous spine surgery, total spinal levels fused, estimated blood loss, and duration of hospital stay as NOBMP (n = 107; P > 0.05). BMP had greater Charlson Comorbidity Index (1.9 vs. 1.2), greater scoliosis (43 vs. 38), longer operative time (488.2 vs. 414.6 min), more osteotomies per patient (4.0 vs. 1.6), and greater percentage of anteroposterior fusion (APSF; 20.9% vs. 8.4%) than NOBMP, respectively (P < 0.05). BMP had more total complications per patient (1.4 vs. 0.6) and more minor complications per patient (0.9 vs. 0.2) than NOBMP, respectively (P < 0.05). NOBMP had more complications requiring surgery per patient than BMP (0.3 vs. 0.2; P < 0.05). Major, neurological, wound, and infectious complications were similar for NOBMP, BMP, PBMP, IBMP, and I + PBMP (P > 0.05). Multivariate analysis demonstrated small to nonexistent correlations between rhBMP-2 use and complications. Conclusion. RhBMP-2 use and location of rhBMP-2 use in ASD surgery, at reported doses, do not increase acute major, neurological, or wound complications. Research is needed for higher rhBMP-2 dosing and long-term follow-up.