Controversial Issues Regarding Positive Bone Margins in Surgery for Diabetic Foot Osteomyelitis: A Pilot Study

Obtaining clean margins in patients who undergo surgical treatment for diabetic foot osteomyelitis (DFO) is recommended. We hypothesize that the rate of recurrence of the infection is not associated with positive margins, even when using a short-term duration of postoperative antibiotic treatment. We conducted a retrospective pilot study of patients who underwent surgery for DFO confirmed by histopathological analysis of the resected bone from August 1, 2020, to December 1, 2020. Bone samples were taken from the proximal margins to be studied by microbiology and histopathology. Twenty-five (89.3%) patients underwent conservative surgery, and 3 (10.7%) patients underwent a minor amputation. After surgery, the antibiotics were stopped in 19 (67.9%) patients and continued in 9 (32.1%) patients for a median period of 4 days. The microbiology of the bone margins was positive in 20 (71.4%) cases, but the histopathology of the bone margins was positive in just 7 (25%) cases. Recurrence of the infection was detected in 3 (10.7%) patients. Seventeen (68%) patients with microbiological-positive margins did not have a recurrence of infection, while 3 (100%) patients had a recurrence of infection (P = .53). Six (24%) patients among those with histopathological-positive margins did not have a recurrence of infection, and1 (33.3%) patient had a recurrence of infection (P = 1). The recurrence of infection was low and always detected in soft tissues, including the cases with a histopathological-positive bone margin. Postoperative antibiotics were administered for a short period of time and not based on the analysis of bone margins.