Spinal Dysraphism is a generalised term for a group of congenital abnormalities that can cause progressive neurological damage and therefore the deterioration of neural and physical function. The abnormalities are also sometimes known as neural tube defects. The feature common to all the conditions is an anomaly in the midline structures of the back, especially the absence of some of the neural arches (outward facing bony parts of the vertebrae), and damage to the skin, filum terminale, nerves and the spinal cord itself. It is therefore a congenital condition in most cases rather than acquired by injury.
Spina Bifida Occulta can also occur without a tethered cord. It is known that 5-10% of the general population may have mild spina bifida but in most cases the damage is limited to one or two vertebrae, the defect is invisible and overall it causes no neurological, musculo-skeletal, or bladder and bowel problems. Some people may suffer from backache which may be investigated through their GP and perhaps x-rays taken, and the condition may be detected by accident.