Surgical site infections following operative management of cervical spondylotic myelopathy: prevalence, predictors of occurence, and influence on peri-operative outcomes

Purpose: Studies have examined infection rates following spine surgery and their relationship to post-operative complications and increased length of stay. Few studies, however, have investigated predictors of infection, specifically in the setting of operative intervention for cervical spondylotic myelopathy (CSM). This study aims to identify the incidence and factors predictive of infection amongst this cohort. Methods: This study performed a retrospective review of the prospectively collected American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Patients included those treated surgically for CSM (ICD-9 code 721.1) from 2010 to 2012. Patient demographics and surgical data were collected with outcome variables including the occurrence of one of the following surgical site infections (SSIs) within 30 days of index operation: superficial SSI, deep incisional SSI, and organ/space SSI. Results: 3057 patients were included in this analysis. Overall infection rate was 1.15 % (35/3057), of which 54.3 % (19/35) were superficial SSIs, 28.6 % (10/35) were deep incisional SSI, and 20 % (7/35) were peri-spinal SSI. Logistic regression revealed factors associated with SSI included: higher BMI [OR 1.162 (CI 1.269–1.064), p = 0.001] and operative time ≥208 min [OR 4.769 (CI 20.220–1.125), p = 0.034]. Conclusions: The overall SSI rate for the examined CSM cohort was 1.15 %. This study identified increased BMI and operative time ≥208 min as predictors of infection in surgical CSM patients. This information should be carefully considered in delivering patient education and future efforts to optimize risk in CSM patients indicated for surgical intervention.