Risk factors for medical complication after cervical spine surgery: a multivariate analysis of 582 patients.

STUDY DESIGN: Multivariate analysis of prospectively collected registry data. OBJECTIVE: Using multivariate analysis to determine significant risk factors for medical complication after cervical spine surgery. SUMMARY OF BACKGROUND DATA: Several studies have examined the occurrence of medical complication after spine surgery. However, many of these studies have been done using large national databases. While these allow for analysis of thousands of patients, potentially influential covariates are not accounted for in these retrospective studies. Furthermore, the accuracy of these retrospective data collection in these databases has been called into question. METHODS: The Spine End Results Registry (2003-2004) is a repository of prospectively collected data on all patients who underwent spine surgery at our 2 institutions. Extensive demographic and medical information was prospectively recorded. Complications were defined in detail a priori and were prospectively recorded for at least 2 years after surgery. We analyzed risk factors for medical complication after lumbar spine surgery, using univariate and multivariate analyses. RESULTS: We analyzed data from 582 patients who met our inclusion criteria. The cumulative incidences of complication after cervical spine surgery per organ system are as follows: cardiac, 8.4%; pulmonary, 13%; gastrointestinal, 3.9%; neurological, 7.4%; hematological, 10.8%; and urologic complications, 9.2%. The occurrence of cardiac or respiratory complication after cervical spine surgery was significantly associated with death within 2 years (relative risk, 4.32, 6.43, respectively). Relative risk values with 95% confidence intervals and P values are reported. CONCLUSION: Risk factors identified in this study can be beneficial to clinicians and patients alike when considering surgical treatment of the cervical spine. Future analyses and models that predict the occurrence of medical complication after cervical spine surgery may be of further benefit for surgical decision making.