Post Operative Infection Following Posterior Cervical Spinal Instrumentation in the Vancomycin Powder Era

Introduction: Since the early 2010s, prophylactic vancomycin powder has become widely utilized in spine surgery, with many surgeons crediting its application for low surgical site infection (SSI) rates of 1-2%. However there remains a lack of consensus within the neurosurgical community regarding the effectiveness of vancomycin powder as a preventive measure.

Methods: The TriNetX Research Network was queried to identify adult patients who underwent single- or multi-level posterior spinal instrumentation with a preoperative diagnosis of cervical spinal stenosis, cervical disc disorder, cervical spondylosis, or cervical radiculopathy. The patient population was divided into two cohorts: (1) those who underwent surgery between January 1, 2003, and December 31, 2013, and (2) those who underwent surgery between January 1, 2014, and December 31, 2023. Propensity score matching (PSM) was performed based on demographics and selected comorbidities. The composite rate of postoperative infection, encompassing infection following the procedure, superficial incisional SSI, deep incisional SSI, organ and space SSI, and procedure-related sepsis as well as postoperative wound infections requiring incision and drainage (I&D) were identified through corresponding procedural and diagnostic codes within 90 days of surgery.

Results: A total of 21,586 patients met the inclusion criteria with 18,156 (84.11%) undergoing surgery between 2014 and 2023, and 3,430 (15.89%) between 2003 and 2013. After PSM, each cohort comprised 3,427 patients. In the matched cohorts, patients who underwent surgery between 2014 and 2023 had significantly lower odds of developing postoperative infection (OR = 0.656, 95% CI [0.493, 0.872]) and comparable odds of requiring I&D for postoperative wound infection (OR = 1.092, 95% CI [0.611, 1.950]) when compared to those who had surgery between 2003 and 2013.

Conclusion : This large-scale, propensity-matched analysis demonstrates that the odds of developing a postoperative infection following posterior cervical spinal instrumentation are approximately 35% lower in the era of prophylactic vancomycin powder, while the rates of I&D for postoperative infection remain consistently low at 0.6-0.7%. These findings suggest that prophylactic vancomycin powder is an effective measure for reducing postoperative infection rates in spine surgery.