Figure 27.

Osteomyelitis in a 42-year-old diabetic man who previously un- derwent transmetatarsal amputation and currently presented with sepsis and soft tissue ulcer over the lateral aspect of the midfoot. There is replace- ment of a normal fatty marrow signal at the bases of the third and fourth metatarsals on coronal T1-weighted magnetic resonance (MR) image (aster- isks in A) and bone marrow edema-like signal on short TI inversion recovery MR image (asterisks in B), indicative of osteomyelitis. Loss of a normal sub- cutaneous fat signal is observed deep near the ulcer (black arrowhead in A) in continuity with bone marrow abnormality; compared to the area of pre- served subcutaneous fat (white arrowhead). Coronal gadolinium contrast enhanced fat-suppressed T1-weighted MR image (C) demonstrates intense bone marrow enhancement (asterisks in C) and depicts non-enhancing si- nus tract (curved arrows) extending from the ulcer to infected bone