Risk factors for fracture-related infections after low-velocity gunshot fractures to the pelvis.

Background: Although treatments have improved dramatically in recent years, mortality following gunshot wounds (GSW) to the pelvis continue to range between 3 and 20 %. This project was designed to determine the incidence and risk factors associated with pelvic fracture-related infection (FRI) following GSWs to the pelvis given the paucity of evidence regarding this complication.

Methods: A retrospective review of 13 years (1/2010-12/2022) of patients with GSW to the pelvis was performed. Patients meeting inclusion criteria underwent chart review for the development of pelvic FRI and the following additional data elements were extracted: demographics, presence and type of bowel injury, operations performed, complications, use of postoperative antibiotics (≤24 h vs. >24 h), surgical osseous debridement, presence of retained bullet fragments, and bullet trajectory. Discrete variables were analyzed using Wilcoxon rank-sum test, chi-square, and Fischer's exact test. Pearson correlation coefficients were calculated for continuous variables.

Results: 242 patients were included in the study. Concomitant bowel injury was present in 108 patients (45 %). Eleven patients (4.5 %) developed FRI, all of whom had a concomitant bowel injury (p < 0.001). Neither the presence of retained bullet fragments nor the bullet trajectory (through bowel before the bone) was associated with FRI. Antibiotic duration >24 h was not associated with a lower rate of pelvic FRI.

Conclusion: Development of FRI after a GSW to the pelvis occurs in 4.5 % of patients and is significantly associated with concomitant bowel injury, specifically colonic injury. These findings can be used to help guide further studies on the role of prophylactic antibiotics or other strategies to prevent pelvic FRI.