Unusual sites of acute osteomyelitis in childhood.

In children osteomyelitis is common in the long hours of femur, tibia and humerus. This study reports 16 children, aged 2-13 years, with osteomyelitis at unusual sites: in the bones of the thoracic cage including three involving the clavicle; in the spine, foot and elsewhere. In one case, multifocal involvement of the vertebral body and the knee occurred. In two large series reported previously, the incidence of osteomyelitis was 1-3% in the clavicle, 3-8% in the calcaneus and less than 1% in the ribs. Four out of 16 cases (two involving clavicles, one rib and one with multifocal sites of the lesion) required open biopsies and histological examination to achieve the final diagnosis of osteomyelitis; in three of these patients the causative agent was not identified on culture. Staphylococcus aureus was the infective organism in 50% of cases where cultures were obtained. In five cases there was no growth on culture and specific search for less common organisms, including mycobacteria tuberculosis (AAFB), proved negative. It is suggested that in such situations diagnostic problems may present as the clinical and radiological findings may not be specific or conclusive. In such cases early biopsy is mandatory.