Fracture-related infection (FRI) is an important complication after operative management of pelvic and lower-limb fractures. Intrawound topical antibiotic powder—most commonly vancomycin and/or tobramycin—achieves high local antibiotic concentrations when applied during surgery, but its clinical effectiveness and safety profile are not fully established. This systematic review and meta-analysis aimed to evaluate the effect of prophylactic intrawound antibiotic powder compared with standard systemic prophylaxis in patients undergoing operative treatment for pelvic and lower-limb fractures.
The authors performed a systematic search of PubMed, Embase, and the Cochrane Library for randomized controlled trials (RCTs) and observational studies that compared intrawound antibiotic powder (vancomycin and/or tobramycin) versus standard systemic prophylaxis in operatively treated pelvic and lower-limb fractures. Pooled estimates used random-effects models, reporting odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals (CIs). The GRADE approach was applied to assess certainty of evidence.
A total of 14 studies were included: three RCTs and 11 observational studies, comprising 4,906 patients overall. Of these patients, 1,779 received topical antibiotic powder.
Pooled results indicated that intrawound antibiotic powder was associated with reduced odds of fracture-related infection. The combined effect showed an OR of 0.63 (95% CI 0.45 to 0.87), reflecting a relative reduction in the odds of FRI by approximately 37% in the treatment group compared with controls.
Subgroup analyses demonstrated the greatest effect in higher-risk scenarios. For high-risk fractures the OR for FRI was 0.54, and for open fractures the OR was 0.49, indicating larger relative reductions in those subpopulations compared with the overall pooled estimate.
No significant impact of topical antibiotic powder was found for superficial surgical site infection (OR 0.79; 95% CI 0.51 to 1.21). Likewise, there was no significant effect on fracture nonunion (OR 1.03; 95% CI 0.64 to 1.66). Thus, available data did not show increased nonunion risk associated with intrawound powder.
The pooled analyses of organism types identified an increased frequency of Gram-negative organisms in infections occurring in the intervention group (OR 2.52; 95% CI 1.24 to 5.14). Conversely, there was a trend favoring the intervention for Gram-positive organisms (OR 0.42; 95% CI 0.16 to 1.08), though the latter estimate crossed unity. The authors highlight a shift in the microbiologic profile toward Gram-negative pathogens when topical powder is used; this finding warrants further study.
No statistically significant difference was observed for acute kidney injury (AKI) between groups (OR 0.94; 95% CI 0.44 to 2.02). Hospital length of stay did not differ significantly, with a mean difference of -1.72 days (95% CI -4.05 to 0.61). The review reports that safety outcome data derive from relatively few studies and carry lower certainty.
Overall, the authors rated the evidence as of moderate certainty; however, this rating reflects that most data came from observational studies (11 of 14 included studies). Safety outcomes were informed by a smaller number of studies and were judged to have low to very low certainty. These limitations mean the magnitude and generalizability of safety findings should be interpreted with caution. The observed microbiologic shift toward Gram-negative organisms is an important signal that requires additional focused investigation.
Moderate-certainty evidence—predominantly from observational data—indicates that intrawound antibiotic powder (vancomycin and/or tobramycin) is associated with a reduction in fracture-related infection among operatively treated pelvic and lower-limb fractures, with the largest apparent benefit in high-risk and open fractures. No increase in nonunion or AKI was detected. Safety outcomes, however, were reported in few studies with lower certainty, and the increased frequency of Gram-negative infections in the intervention group requires further research. Clinicians should weigh the potential reduction in FRI against limitations in safety evidence and the need for prospective, high-quality trials to clarify microbiologic and adverse-event implications.