These membranes are called the meninges, the outermost membrane is called the dura mater, then the arachnoid and then the pia mater.
The liver, spleen, lungs, bone, skin, and sometimes the membrane surrounding the brain and spine (meninges) may be affected.
This is due to an inflammation of the meninges (tissues which cover the spinal cord and brain).
More commonly, the abnormality appears as a localized mass on the back that is covered by skin or by the meninges, the three-layered membrane that envelops the spinal cord.
The term meningocele is used when the spine malformation contains only the protective covering (meninges) of the spinal cord.
