Study Design. Multivariate analysis of prospectively collected registry data.
Objective. Using multivariate analysis to determine significant risk factors for medical complication after lumbar 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 utilizing large national databases. Although 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 collection of prospectively collected data on all patients who underwent spine surgery at our two institutions. Extensive demographic and medical information were prospectively recorded as described previously by Mirza et al. 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 analysis.
Results. We analyzed data from 767 patients who met out inclusion criteria. The cumulative incidences of complication after lumbar spine surgery per organ system are as follows: cardiac, 13%; pulmonary, 7%; gastrointestinal, 6.7%; neurological, 8.2%; hematological, 17.5%; and urologic complications, 10.3%. The occurrence of cardiac or respiratory complication after lumbar spine surgery was significantly associated with death within 2 years (relative risk: 6.09 and 10.9, respectively). Several significant risk factors were identified for organ-specific complications. Among these, surgical invasiveness appeared to be the largest risk factor for cardiac, pulmonary, neurological, and hematological complications.
Conclusion. Risk factors identified in this study can be beneficial to clinicians and patients alike when considering surgical treatment of the lumbar spine. Future analyses and models that predict the occurrence of medical complication after lumbar spine surgery may be of further benefit for surgical decision making.
Utilizing the Spine End Results Registry (2003–2004), this study performed an exhaustive univariate and multivariate analysis of risk factors for medical complication after lumbar surgery. The relative risk with 95% confidence intervals and P values were determined for numerous potential risk factors. These data can be beneficial when considering surgical treatment of the lumbar spine.
*Department of Orthopedics and Sports Medicine, University of Washington, Seattle, WA;
†Department of Orthopedics and Sports Medicine, Harborview Medical Center, Seattle, WA.
Address correspondence and reprint requests to Michael J. Lee, MD, 1959 Pacific Avenue NE, Box 356500, Department of Sports Medicine and Orthopaedic Surgery, University of Washington Medical Center, Seattle, WA 98195; E-mail: firstname.lastname@example.org
Acknowledgment date: October 14, 2010. Revision date: February 10, 2011. Acceptance date: February 21, 2011.
The manuscript submitted does not contain information about medical device(s)/drug(s).
Corporate/Industry funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript. Approved by the University of Washington Medical Center institutional review board.
Supported by grants NIH/NIAMS 5K23AR48979 and 5P60-AR48093 and supported in part by the Spine End-Results Research Fund at the University of Washington Medical Center through a gift from Synthes Spine (Paoli, PA).