Imaging of osteomyelitis in the mature skeleton.

Diagnosis of acute osteomyelitis is often challenging but can be made by plain radiograph, bone scan, or MR imaging. This diagnosis may be more problematic in small bones, in diabetic or immunocompromised patients, those partially treated, post-traumatic, previous surgery, or with pre-existing marrow conditions and associated soft tissue infections. CT is the modality of choice for revealing sequestra and cortical erosions in chronic osteomyelitis. Nonenhanced and enhanced STIR or fat-saturated sequences are essential to reveal the marrow abnormality and its extension for diagnosis of subtle cases with neuropathic or other associated conditions. Combined radionuclide scintigraphy becomes necessary in complicated situations.