Two patients with acute osteomyelitis had technetium 99m methylene diphosphonate bone images that were misinterpreted. A review of six prospective evaluations of technetium scanning in the diagnosis of acute osteomyelitis shows that bone image interpretation may be misleading in five to seven per cent of pediatric patients. Definitive diagnostic procedures and management should not be delayed until a positive bone scan is obtained, if the clinical findings are persuasive.