Nuclear medicine and the diagnosis of diabetic foot osteomyelitis

The diagnosis of diabetic foot osteomyelitis is often difficult both clinic ally and radiologically with a delay in radiological sign occurrence and di fficulties of imaging interpretation. Bone biopsy is known to be the diagno sis gold standard. However, if negative, the diagnosis of osteomyelitis can not be excluded and this method is not harmless. An early diagnosis of oste omyelitis is necessary to start an antibiotic treatment in conjunction with conservative surgery. Tc-99m-HMPAO labelled leucocyte scintigraphy perform ed in conjunction with bone scintigraphy significantly contributes to the d iagnosis of osteomyelitis (sensitivity = 100% and specificity > 95%). In ca se of osteomyelitis suspicion, after plain radiography, the Tc-99m-MDP bone scintigraphy is the first step. If negative, osteomyelitis is unlikely. If positive, a Tc-99m-HMPAO leucocyte scintigraphy should be performed in ord er to exclude or to confirm the diagnosis of bone infection.