Efficacy of Magnetic Resonance Imaging in Diagnosing Osteomyelitis in Diabetic Foot Ulcers

BACKGROUND: The clinical diagnosis of osteomyelitis is difficult because of neuropathy, vascular disease, and immunodeficiency; also, with no established consensus on the diagnosis of foot osteomyelitis, the reported efficacy of magnetic resonance imaging (MRI) in detecting osteomyelitis and distinguishing it from reactive bone marrow edema is unclear. Herein, we describe a retrospective study on the efficacy of MRI for decision-making accuracy in diagnosing osteomyelitis in diabetic foot ulcers. METHODS: Twelve diabetic patients with infected foot ulcers underwent preoperative MRI between January 1, 2008, and December 31, 2011. The findings were compared with the histopathologic features of 67 parts of 45 resected bones, the cut ends of which were also histopathologically evaluated. RESULTS: Osteomyelitis was disclosed by MRI and histopathologically confirmed in 30 parts. In contrast, bone marrow edema diagnosed by MRI in 29 parts was confirmed in 23; the other six parts displayed osteomyelitis. Among 17 resected bones, 13 cut ends displayed bone marrow edema and four were normal. All of the wounds healed uneventfully. CONCLUSIONS: In the diagnosis of diabetic foot ulcers, osteomyelitis is often reliably distinguished from reactive bone marrow edema, except in special cases.