Spinda bifida occulta is the commonest form of spina bifida, and is estimated to affect between 10-20% of the population in most western countries.
As there is overlying skin covering the vertebral defect and no associated developmental abnormalities of the cord or nerve roots, there are no usually no accompanying neurological symptoms found.
Spina bifida occulta is a congenital defect which occurs when the bony plates that form the bony spine covering the spinal cord do not form completely resulting in a defect of the neural arch. This usually involves the lower lumbosacral spine.
Appears as a midline bony defect at the posterior arch.
This is the test of choice to assess for suspected spina bifida and determine its extent.