SPINA BIFIDA

A bony defect in the vertebral column through which the meningeal membrane and spinal cord may protrude (spina bifida cystica) or may not protrude so that the defect remains hidden, covered by skin (spina bifida occulta). Spina bifida cystica, also known as meningomyelocele (MM), is due to failure of closure during embryonic life of bottom end of the neural tube, the structure which gives rise to the central nervous system (the brain and spinal cord). The term spina bifida refers specifically only to the bony defect in the vertebral column but, through usage, the term spina bifida is gradually becoming synonymous with MM. The risk of spina bifida (and all neural tube defects) can be decreased by the mother eating ample folic acid during pregnancy.