Impact of Local Vancomycin on Postoperative Outcomes in Ankle Arthrodesis: A Propensity-Matched Cohort Study.

Abstract

In orthopaedic surgery, intrawound vancomycin has become a widely used strategy to reduce the incidence of surgical site infections, commonly caused by gram-positive microorganisms. This study evaluated the incidence of postoperative orthopaedic complications in patients undergoing ankle arthrodesis with and without the use of intrawound vancomycin. This retrospective study used data from the TriNetX Research Network to identify patients who underwent ankle arthrodesis between October 1, 2002, and October 1, 2022. This population was divided into two cohorts: patients who received perioperative cefazolin and local vancomycin (cefazolin-vancomycin) and patients who received perioperative cefazolin but no local vancomycin (cefazolin-only). This study assessed rates of implant-related complications occurring within 2 years of the arthrodesis. A total of 374 patients in the cefazolin-vancomycin cohort and 5,218 in the cefazolin-only cohort were identified, with an average age of 58.0 ± 14.0 years and 56.6 ± 14.6 years, respectively (P = 0.083). Before matching, the cefazolin-vancomycin cohort had higher rates of comorbidities, including diabetes (30% vs. 21%, P < 0.001), obesity (32% vs. 21%, P < 0.001), and liver disease (13% vs. 5%, P < 0.001). After propensity matching, each cohort had 373 patients. The cefazolin-vancomycin group demonstrated a significantly lower risk of nonunion (13% vs. 19%, P = 0.020), whereas other outcomes showed no statistically significant differences. This study evaluated the incidence of postoperative complications in patients undergoing ankle arthrodesis with and without intrawound vancomycin. The analysis demonstrated a markedly lower nonunion rate in the cefazolin-vancomycin group (13%) compared with the cefazolin-only group (19%), aligning with previously reported rates but lower than those seen in high-risk populations. These findings suggest that local vancomycin administration may mitigate nonunion risk and optimize fusion outcomes in ankle arthrodesis by reducing infection.