Subacute osteomyelitis of the femur due to Fusobacterium nucleatum in a 7-year-old boy.

Subacute hematogenous osteomyelitis is an insidious infection, which commonly has a delayed diagnosis. We describe the case of a 7-year-old boy with subacute osteomyelitis, which was initially considered to be a bone tumor. Infection should be considered in all cases of bone pain, especially in children, even in the absence of typical systemic features of inflammation.