Spina bifida literally means ‘split spine’
A fault in the development of the spinal cord and surrounding bones (vertebrae) leaves a gap or split in the spine. The spinal cord has not formed properly, and may also be damaged. To help understand what it is, it is useful to explain the composition of the nervous system.
The Central Nervous System
The central nervous system consists of the brain and the spinal cord. All activities are controlled by the brain which receives information from touching, seeing, feeling, tasting and hearing – responding to this information by initiating the appropriate movements of different parts of the body. Messages from the brain are carried to different parts of the body by the spinal cord which runs down the centre of the spinal column. This communication system for the body is very important and needs protection.
The spine is made up of 33 bones or vertebrae. The vertebrae have two main functions. One is to provide anchorage for muscles so that we can move as the brain dictates to those muscles. The other is to provide protection to the spinal cord.
The Neural Tube
The central nervous system and spine develops between the 14th and 23rd day after conception. Spina bifida occurs when the neural tube fails to close correctly. The vertebrae also fail to close in complete rings around the affected portion of the spinal cord. This leaves a gap posteriorly (at the back), involving one or more vertebrae. The fault may occur in one or more of the vertebrae but it is most common around waist-level.