Risk Factors for Surgical Site Infection in Spinal Surgery and Interventions: A Retrospective Study

Background: Surgical site infection following spinal surgery causes prolonged delay in recovery after surgery, increases cost, and sometimes leads to additional surgical procedures. We investigated risk factors for the occurrence of surgical site infection events in terms of patient-related, surgery-related, and postoperative factors.Methods: This retrospective study included 1000 patients who underwent spinal surgery in our hospital between April 2016 and March 2019. Before September 2015, we observed multiple occurrences of spinal surgical site infections caused by methicillin-resistant Staphylococcus aureus, and we have since been culturing swabs taken from inside and outside the wound before postoperative wound closure as a form of surgical site infection surveillance.Results: The patient-related factors of dementia, length of preoperative hospital stay (≥14 days), diagnosis at the time of surgery (traumatic injury or deformity), surgery-related factor of multilevel surgery (≥9 intervertebral levels), and postoperative factor of time to ambulation (≥7 days) were statistically significant risk factors for spinal surgical site infection. A retrospective study of 392 patients who underwent spinal surgery between June 2009 and August 2011, before surgical site infection surveillance was implemented, showed that the incidence of surgical site infection was 4.59%, although in this study, it had dropped to 2.0%.Conclusion: The introduction of surgical site infection surveillance thus helps reduce the incidence of surgical site infection through measures taken by medical staff to prevent them and to improve associated problems. One risk factor identified in this study that is amenable to intervention is the time to ambulation. As delayed ambulation is a risk factor for postoperative surgical site infection, how medical staff can intervene in postoperative ambulation to further reduce the incidence of surgical site infection is a topic for future research.