Intradural cervical disc herniation and Brown-Séquard's syndrome. Report of three cases and review of the literature.

Although cervical disc herniation commonly requires surgical intervention, the intradural sequestration of a herniated cervical disc fragment is rare. In searching the world literature on this topic, the authors found six case reports. They report three new cases of intradural cervical disc herniation in which the patients presented with Brown-Séquard's syndrome and they review the literature. Although Brown-Séquard's syndrome is a rare clinical finding in extradural disc herniation, six of the nine patients with intradural cervical disc herniation (our cases and those from the literature) presented with symptoms of this syndrome. The remaining patients presented with para- or quadriparesis. This suggests that intradural disc herniation should be considered preoperatively in patients in whom there is magnetic resonance imaging or myelographic evidence of cervical disc herniation and Brown-Séquard's syndrome. In patients who underwent anterior cervical discectomy for the treatment of intradural cervical disc herniations, better outcomes were demonstrated than in those in whom posterior procedures were performed.