Heterotopic dorsal-root ganglion cells around the spinal cord in children with spina bifida aperta.

Sixty-three of 95 cords from children with spina bifida aperta had associated heterotopic ganglion cells, usually located in dorsal nerve roots posterior or lateral to the cord. Heterotopic cells were more common in cords with complete or partial diplomyelia, and the largest number was found in the upper sacral region. It is proposed that the heterotopic position of the cells is due to abnormal and delayed migration of neural crest cells during primary neurogenesis. The findings lend support to the concept that in children with myelomeningocele the cord lesion is not due to secondary rupture.