BMP-7 (OP-1) safety in anterior cervical fusion surgery

Bone morphogenetic proteins (BMPs) are increasingly used in spinal fusion surgery. Previous reports of BMP use in anterior cervical fusion have suggested high rates of complications related to soft tissue swelling. We evaluate the safety of using BMP-7 osteogenic protein (OP-1); Stryker, Kalamazoo, MI, USA) in a relatively contained form and controlled dose. A prospective consecutive cohort of 131 patients underwent anterior cervical discectomy and fusion using interbody cages. In 123 of these patients, BMP-7 was also used. The primary outcome measure was the presence (or otherwise) of clinical adverse events during the first 30 days. The secondary outcome was the extent of radiological soft tissue swelling as measured on plain radiographs in the early post-operative period. There was no mortality and no reoperation in this series; however, 2.4% of patients experienced complications of transient brachalgia (1 patient), and dysphagia (2 patients). The use of BMPs in spinal fusion is discussed, and the relevant literature reviewed, particularly as it relates to adverse clinical events. We concluded that BMP-7 can be used safely in anterior cervical fusion. The effect of BMP-7 on the rate and timing of fusion, as well as clinical outcome, is yet to be elucidated.