Hospital outcomes and complications of anterior and posterior cervical fusion with bone morphogenetic protein

Abstract

Study design: Retrospective database analysis.

Objective: A nationwide population-based database was analyzed to identify the incidence of complications and mortality associated with bone morphogenetic protein (BMP) utilization in cervical spine fusion surgery.

Summary of background data: "Off-label" use of BMP as an adjunct in cervical fusions has been associated with increased complication rates in small case series. The incidence of complications with utilization of BMP is not well characterized on a national level.

Methods: Data from the Nationwide Inpatient Sample were obtained for each year from 2002-2009. Patients undergoing anterior cervical fusion (ACF) or posterior cervical fusion for diagnoses of cervical myelopathy and/or radiculopathy were identified and separated into cohorts ("BMP" and "No BMP"). Patient demographics and comorbidities were compared. Complications, length of stay, costs, and mortality rates were assessed. Student t test and χ test were used to assess significant differences. A P value of less than 0.0005 was used to denote significance.

Results: A total of 213,421 ACFs and 20,334 posterior cervical fusions were identified from 2002-2009; 6.2% of all ACFs and 12.5% of posterior cervical fusions utilized BMP. Patients receiving BMP in the ACF group were older with greater comorbidities than patients who did not receive BMP (P < 0.0005). Both surgical groups with BMP experienced increased length of stay and costs. Overall complication rates were significantly greater when BMP was utilized in ACFs (P < 0.0005) due to a significantly higher rate of dysphagia (37.2 vs. 22.5 per 1000 cases) (P < 0.0005).

Conclusion: Our study found that "off-label" use of BMP as an adjunct to cervical fusions was associated with increased rates of dysphagia in ACFs and increased costs for all cervical fusions. Our study does not measure long-term outcomes after discharge; however, the impact of increased inhospital costs, length of stay, and incidence of dysphagia with utilization of BMP should be considered prior to its use in cervical fusions.