Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Spina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae of the spinal cord are not fully formed and stay unfused and open. When the opening is large enough, it allows a portion of the spinal cord to stick out through the opening in the bones where there may or may not be a fluid-filled sac surrounding the spinal cord... Learn more about spina bifida, the related condition hydrocephalus, and other related matters such as the neural tube and the vertebral column with the help of this book.