The role of diagnostic imaging in the evaluation of suspected osteomyelitis in the foot: a critical review.

The early diagnosis of osteomyelitis in the foot from its clinical presentation alone can be difficult particularly in cases when the early signs are subtle. Early diagnosis and subsequent early intervention are imperative to reduce the risk of chronic infection, associated early lytic changes to bone and potential long term structural complications caused by subsequent deformity and lost anatomy. Diagnostic imaging has a major role to play in the early assessment and diagnosis of bone infection, yet the choice of approach can be controversial. Several imaging modalities have been advocated, imaging of the infected foot is complex and no single test is ideal for every situation. The clinician needs to be aware of the strengths and weaknesses of each imaging modality so that the most appropriate test is selected for the individual case. Factors such as site of infection in the foot, the aggressive nature of the organism, the time since onset, previous associated surgery and co-morbidity may all play apart in the clinician's decision making process to determine the best approach in detecting the sometimes subtle changes which may be seen in some cases of osteomyelitis. This review considers the literature and highlights the advantages and disadvantages of the main imaging techniques used for the evaluation of the foot when osteomyelitis is suspected. An evidence based algorithm for the selection of appropriate imaging techniques is suggested to aid clinicians in there decision making process.