Spinal cord injury without radiographic abnormality and Chiari malformation.

Spinal cord injury without radiographic abnormality and asymptomatic Chiari I malformation have an unusual coincidence. A young boy who had recently fallen from his porch was transferred to the neurosurgery service with a high cervical central cord syndrome. Careful study demonstrated no radiographic abnormality and, although the patient was previously quite well, magnetic resonance imaging revealed Chiari I malformation. Although expectedly uncommon, reports of three other similar cases support a less than independent relationship between these two processes. All four children, each aged 2 years, were premorbidly asymptomatic and were playing when they fell from low elevations; two were on a couch. All were evaluated by primary authorities 12 to 48 hours before definitive admission, and all had normal plain film examinations. Three of the four children suffered injuries in flexion, the fourth in extension. Three realized a 5-minute to 3-hour delay before the onset of symptoms, and three suffered gradual progression of deficit. Magnetic resonance imaging was the most commonly applied and productive diagnostic medium, demonstrating cerebellar ectopia in three of three cases. Two children were surgically treated, and all achieved at least a functional outcome. Similarities among these cases support a common mechanism of injury, and indicate careful counseling in children with asymptomatic Chiari I malformation and consideration of operative decompression in those children with progressive neurological injury and deficit.