Confirmation by magnetic resonance imaging of Bell's cruciate paralysis in a young child with Chiari type I malformation and minor head trauma.

We report the case of a young girl who suffered bilateral upper extremity paralysis after minor head trauma. Her clinical picture, as well as radiographic evidence of a fracture at C1, led to the diagnosis of Bell's cruciate paralysis, caused by a small lesion in the rostral part of the pyramidal decussation. Magnetic resonance images showed, in addition to a Chiari Type I malformation, an abnormality in the medulla. All previous cases of cruciate paralysis lack both pathological and radiographic supporting evidence.