Agricultural Trauma causing Open Fractures: Is Antibiotic Coverage against Anaerobic Organisms Indicated?

OBJECTIVE To compare deep infection rate and causative organisms in open fractures of the lower extremity from agricultural trauma to similar injuries in non-agricultural trauma. DESIGN Retrospective. SETTING Two tertiary-care institutions. METHODS Open lower extremity fractures sustained between 2003-2018 by agriculture-related trauma in adult patients were reviewed. A non-agriculture open fracture control group was identified for comparison. Patient demographics and injury characteristics were assessed. Outcomes included occurrence of deep infection and causative organism. RESULTS 178 patients were identified in the agriculture(AG) (n=89) and control(NAG) (n=89) groups. Among agricultural-injury patients, farm machinery was the most common mechanism in 69 (77.5%) patients. Open injuries of the foot (38.2%) were most common in the AG-group and tibial shaft (25.8%) in the NAG-group.Deep infection was seen in 21% of the AG-group compared to 10% in the NAG-group(p<0.05). AG-group anaerobic infection occurred in 44% of patients with deep infection versus 9.1% in NAG-group(p<0.05). Most common anaerobic organisms included Enterococcus, Pseudomonas aeruginosa, and Clostridium perfringens. CONCLUSION This study supports that open fractures due to agricultural trauma have a high infection rate, with anaerobic infection occurring at higher rates than in non-agricultural trauma. Prophylactic treatment with antibiotics directed against anaerobes is indicated in these injuries. LEVEL OF EVIDENCE Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.