Background and Objectives
The study, published in the Journal of Clinical Medicine (2026), aimed to compare the effectiveness of chlorhexidine (CHG)-based and iodine-based skin preparations in reducing 90-day postoperative infection risk after instrumented degenerative cervical or lumbar spine surgery. Chlorhexidine and iodine-based antiseptics are commonly used in surgical settings, with prior research suggesting potential advantages of chlorhexidine in clean elective procedures. However, the study sought to determine whether this benefit extends to instrumented degenerative spine surgeries, which involve the placement of hardware such as screws or rods. The primary objective was to evaluate if CHG-based preparations reduce postoperative infections compared to iodine-based preparations, with secondary outcomes including specific types of surgical site infections and related complications.
Study Design and Participants
The research utilized a retrospective cohort study design through the TriNetX database, analyzing data from adults who underwent instrumented degenerative cervical or lumbar spine surgery. Patients were categorized based on the type of skin preparation used—CHG-based or iodine-based—and further stratified by anatomic region (cervical or lumbar). A 1:1 propensity score matching was conducted within each anatomic group to balance baseline characteristics, including demographics, Charlson Comorbidity Index (CCI), diabetes, smoking status, obesity, BMI, immunosuppression, methicillin-resistant Staphylococcus aureus (MRSA) carrier status, and surgical procedure codes. The cervical cohort included 3,528 matched pairs (3,528 patients per group), while the lumbar cohort had 4,164 matched pairs (4,164 patients per group). Baseline characteristics, such as age and comorbidities, were comparable between the matched groups.
Key Findings
The study found no statistically significant difference in 90-day postoperative infection rates between CHG-based and iodine-based skin preparations in either the cervical or lumbar cohorts. In the cervical group, the infection rate was 1.76% for CHG and 1.59% for iodine (risk ratio [RR] 1.11, 95% confidence interval [CI] 0.77–1.58; p = 0.578). In the lumbar group, the rates were 3.17% for CHG and 3.29% for iodine (RR 0.96, 95% CI 0.76–1.22; p = 0.757). Secondary outcomes, including superficial and deep surgical site infections, MRSA infections, debridement, sepsis, urinary tract infections, and pneumonia, also showed no significant differences between the groups. These findings suggest that neither antiseptic preparation demonstrated a clear advantage in reducing postoperative complications after instrumented spine surgery.
Discussion and Implications
The study’s results contrast with some previous literature suggesting a potential benefit of CHG in clean surgical settings. However, the authors noted that spine surgeries are classified as clean (class I) wounds, and the antiseptic literature in such contexts may not directly apply. The study highlights that the CHG advantage observed in broader orthopedic or clean surgery populations may not translate to instrumented spine procedures. The authors speculated that differences in preparation composition, such as the alcohol-based carrier in CHG, might influence outcomes, though the study did not directly compare formulations. Additionally, microbiological studies on skin flora eradication showed mixed results, with some trials finding equivalent efficacy between CHG and iodine. The lack of significant differences in this study could reflect the specific patient populations, surgical techniques, or antiseptic application methods used in spine surgery. Further research is needed to clarify the role of antiseptic choice in reducing infections in this context.
Limitations
The study has several limitations inherent to its retrospective and observational design. Despite propensity score matching to account for confounding variables, unmeasured factors such as differences in surgical technique or intraoperative practices could still influence outcomes. The reliance on procedure codes and documentation within the TriNetX database may have led to incomplete or inaccurate coding of antiseptic use, as field preparation is not always recorded as a medication. Additionally, the study could not account for the use of intrawound vancomycin powder or other local antibiotic measures, which are inconsistently coded. These limitations underscore the need for future randomized controlled trials to validate these findings and better understand the impact of antiseptic selection on postoperative infection rates in spine surgery.