Spina Bifida and Related Conditions

The term “spinal dysraphism” encompasses the broadest array of the conditions known as the neural tube defects. The open neural tube defects (spina bifida aperta and cystica) include both disorders of primary and/or secondary neuralation and are best defined as myelomeningocele complex (MMC) due to their protean nervous system manifestations beyond the spinal lesion. Closed spinal dysraphisms (so-called spina bifida occulta) include lipomatous lesions, forms of tethered spinal cord, sinus tracts, and forms of split spinal cord (diastematomyelia). Both genetic and environmental etiologies have been identified. Gene-environment and gene-gene interactions are also important in the pathobiology of these conditions.