Incidence and risk factors of wound complications in long segment instrumented thoracolumbar spinal fusions: a retrospective study.

Background: This is a retrospective analysis of prospectively collected data. Our objective was to determine the incidence and assess the risk factors associated with surgical site wound complications in long segment (7+ vertebrae) instrumented thoracolumbar fusions. Surgical site complications lead to patient morbidity, increased financial burden, and further medical intervention. Risk factors for wound complications in spinal surgery include patient factors such as obesity and diabetes, and surgical factors such as operative time and procedure type. Fusion with instrumentation is one of the strongest associated risk factors in the literature.

Methods: A comprehensive search of the National Surgical Quality Improvement Program (NSQIP) from 2005 to 2014 was performed, selecting cases based on Current Procedural Terminology (CPT) codes. Cases were then stratified based on the presence of one of the following wound complications: superficial surgical site infection, deep surgical site infection, organ space infection, and wound dehiscence. Univariate and bivariate analyses were performed to determine risk factors.

Results: A total of 2,548 cases were identified, and the most common diagnoses were scoliosis (29%), spondylosis (17%) and spinal stenosis (14%). Overall, 4.24% of cases had at least one wound complication. Identified risk factors include obesity, preoperative transfusion, preoperative wound infection, and operative time. Associated outcomes include stroke with neurological deficit, perioperative transfusion, deep vein thrombosis (DVT), sepsis, septic shock, readmission, reoperation, and longer length of hospital stay. Many of these variables are independently associated with a wound complication.

Conclusions: Our analysis of the NSQIP demonstrated risk factors and complications associated with wound infections in the setting of long segment fusions (7+ levels). These findings may aid surgeons in determining a patient's risk of developing a wound complication, with the goal of lessening the associated morbidity and economic burden.