CERVICAL SPINE REOPERATION RATES AND HOSPITAL RESOURCE UTILIZATION AFTER INITIAL SURGERY FOR DEGENERATIVE CERVICAL SPINE DISEASE IN 12 338 PATIENTS IN WASHINGTON STATE

OBJECTIVE: Patients undergoing surgery for degenerative cervical spine disease may require future Surgery for disease progression. We investigated factors related to the rate of additional cervical spine Surgery, the associated length of stay, and hospital charges. METHODS: The was a longitudinal retrospective cohort study using Washington state's 1998 to 2002 state inpatient databases and International Classification of Diseases-Ninth Revision-Clinical Modification (ICD-9) codes to analyze patients undergoing cegenerative cervical spine surgery. Multivariate Poisson regression to identify patientand surgical factors associated with reoperation for degenerative cervical spine disease was used. Multivariate linear regressions to identify factors associated with length of stay and hospital charges adjusted for age, Sex, year of surgery, primary diagnosis, payment type, discharge status, and comorbidities were also used. RESULTS: A total of 12 338 patients underwent initial cervical spine surgeries from 1998 to 2002; the mean follow-up duration was 2.3 years, and 688 patients (5.6%) underwent a reoperation (2.5% per year). Higher reoperation rates were independently associated with younger patients (P < 0.001) and a primary diagnosis of disc herniation with myelopathy (P = 0.011). Ventral surgery (P < 0.001) and fusion (P < 0.001) were both associated with lower rates of reoperation; however, a high correlation (Spearman's rho = 0.82; P < 0.001) made it impossible to determine which factor was dominant. Longer length of stay was independently associated with nonventral approaches (+1.0 day; P < 0.001) and fusion surgery (+0.8 day; P < 0.001). Greater hospital charges were independently associated with nonventral approaches (+$2900; P < 0.001) and fusion Surgery (+$9600; P < 0.001). CONCLUSION: Patients undergoing surgery for degenerative cervical spine disease undergo reoperations at the rate of 2.5% per year. An initial ventral approach and/or fusion seem to be associated with lower reoperation rates. An initial nonventral approach and fusion were more expensive.