What can help establish the diagnosis of acute osteomyelitis on MRI?
First, clinical history that is suggestive of infection is useful to make a diagnosis of acute osteomyelitis. Additionally, other findings of infection often are encountered, including skin ulceration, cellulitis, fasciitis, pyomyositis, phlegmon, and abscess. The presence of such findings increases confidence that the bone marrow edema represents acute osteomyelitis. In particular, if a skin ulcer is seen to directly communicate with a bone that demonstrates bone marrow edema, then the diagnosis of osteomyelitis is almost certain.