Bilateral upper extremity paralysis (Bell's cruciate paralysis) from a gunshot wound to the cervicomedullary junction.

Cruciate paralysis is characterized by midline involvement of the rostral portion of the pyramidal decussation, resulting in paralysis of the upper extremity without lower extremity involvement. The neuroanatomical basis is the more rostral and medial decussation of the upper extremity motor fibers in the medulla compared with the more caudal and lateral decussating fibers of the lower extremity at the lower boundary of the cervicomedullary junction. We believe this to be the first reported case of Bell's cruciate paralysis caused by a gunshot wound to this region. The neuroanatomical basis and the mechanisms that produce this unique clinical entity are discussed.