Study design: A retrospective cohort study.
Objective: To compare the complications between posterior cervical fusions with and without recombinant human bone morphogenetic protein 2 (rhBMP2).
Summary of background data: Use of rhBMP2 in anterior cervical spinal fusion procedures can lead to potential complications such as neck edema, resulting in airway complications or neurological compression. However, there are no data on the complications associated with the "off-label" use of rhBMP2 in upper and lower posterior cervical fusion approaches.
Materials and methods: Patients from the PearlDiver database who had a posterior cervical fusion between 2005 and 2011 were identified. We evaluated complications within 90 days after fusion and data was divided in 2 groups: (1) posterior cervical fusion including upper cervical spine O-C2 (upper group) and (2) posterior cervical fusion including lower cervical spine C3-C7 (lower group). Complications were divided into: any complication, neck-related complications, wound-related complications, and other complications.
Results: Of the 352 patients in the upper group, 73 patients (20.7%) received rhBMP2, and 279 patients (79.3%) did not. Likewise, in the lower group of 2372 patients, 378 patients (15.9%) had surgery with rhBMP2 and 1994 patients (84.1%) without. In the upper group, complications were observed in 7 patients (9.6%) with and 34 patients (12%) without rhBMP2. In the lower group, complications were observed in 42 patients (11%) with and 276 patients (14%) without rhBMP2. Furthermore, in the lower group the wound-related complications were significantly higher in the rhBMP2 group (23 patients, 6.1%) compared with the non-rhBMP2 group (75 patients, 3.8%).
Conclusions: Our data showed that the use of rhBMP2 does not increase the risk of complications in upper cervical spine fusion procedures. However, in the lower cervical spine, rhBMP2 may elevate the risk of wound-related complications. Overall, there were no major complications associated with the use of rhBMP2 for posterior cervical fusion approaches.
Level of evidence: Level III.