Infectious morbidity associated with colonic trauma was evaluated with respect to the specific site of the colonic injury, the surgical method used, and the antibiotic treatment prescribed. Septic complications were more frequent among patients who had left-sided colon injuries (P = less than 0.01) and among those who received antibiotics known to be ineffective against anaerobic bacteria (P = less than 0.01). A statistical analysis of the different surgical methods used, i.e., primary repair of the colon, primary repair with loop exteriorization, or colostomy, was indeterminable.