Acute infarction of long bones in children with sickle cell anemia

The clinical features of long bone infarction in patients with sickle cell disease have not been well defined, and differentiation of bone infarct from osteomyelitis has accordingly been difficult. We reviewed records from 192 children with sickle hemoglobinopathies and identified 41 episodes of acute long bone infarction in 21 patients. The most commonly affected bones were the humerus (38%), tibia (23%), and femur (19%). The distal segment was more commonly involved. Tenderness and prominent swelling occurred in all cases; other findings included impaired joint motion (68%), local heat (65%), and erythema (14%). Fever was usually absent or low grade, and patients did not appear ill. Laboratory studies included negative bacterial cultures in all cases, absence of left shift in WBC count in most, and variable erythrocyte sedimentation rate. Plain roentgenographs were unremarkable. Contrary to previous reports, radionuclide bone and bone marrow scans were not helpful in differentiation of bone infarction from osteomyelitis. Patients received supportive therapy and improved within several days. Long-term sequelae were not evident. The rarity of osteomyelitis in our sickle cell population (five cases in 22 years) precluded direct comparison of most of its clinical features with those of bone infarction. Acute long bone infarction is at least 50 times more common than bacterial osteomyelitis in sickle cell disease.