Cefazolin is given routinely pre and intraoperatively for patients undergoing spinal surgery to reduce the rate of infection. Intra-wound admission of Vancomycin powder has been suggested to reduce wound infection rates. Therefore, this study aims to compare the rate of wound-related complications between patients receiving standard treatment compared to patients receiving an addition of topical Vancomycin and to identify the optimal Vancomycin dosage. All groups will receive the recommended regimen of routine IV antibiotic prophylaxis.

Inclusion Criteria:

• Patients undergoing posterior spinal fusion operation at the neurosurgery department at the Rabin Medical Center
• Ability to understand and sign written informed consent by the patient or legal guardian

Exclusion Criteria:

• Preoperative ongoing infectious disease present as judged by the primary surgeon (based on lab results and clinical assessment)
• Receiving ongoing treatment of antibiotics for other infections
• Sensitivity or allergy to vancomycin or cefazolin
• Previous spine surgery at the index level within the last 90 days
• Postoperative radiotherapy of the surgical site required (e.g. for tumor)
• Renal insufficiency with stage 4 chronic kidney disease (CKD) with a glomerular filtration rate (GFR) of 15-30 ml/min or worse
• Undergoing spinal decompression only
• Trauma patients
• Pregnancy