Objective:

Surgical site infection (SSI) is a well-documented complication in patients that undergo posterior spine instrumentation, with most studies reporting an incidence of 1-12%. Some studies have documented that a diluted sterile povidone-iodine (PVI) solution can be safely used in posterior spinal fusion surgeries as an antiseptic. In this study, we analyzed its effectiveness in reducing SSI.

Methods:

This retrospective study consisted of consecutive elective patients who underwent posterior lumbar instrumentation by a single surgeon from 2016-2019. The first 134 patient’s wounds were irrigated before arthrodesis and closure with 1 liter of 0.9% normal saline solution (NSS) and the following 144 with a solution of 35mL of sterile 10% PVI. Both groups were analyzed to determine if wound irrigation with a sterile PVI solution decreased SSI.

Results:

There were nine (6.7%) SSIs in the 0.9% NSS group vs. one (0.7%) in the PVI group (p=0.008). The PVI solution had a RR for SSI of 0.093 (p=0.008) and an adjusted OR 0.113 (p=0.05). Increased BMI and the PLSF-L were significant risk factors for SSI (p=0.04) and (p=0.030), respectively.

Conclusion:

Wound irrigation with a PVI solution significantly reduced SSI on elective posterior lumbar instrumentation cases. The subgroup analysis provided significant results to recommend its use for SSI prevention, particularly in overweight and obese patients. We also recommend its use in patients with risk factors for SSI, such as longer operative time and unintended durotomy.