In this most severe form, the spinal opening typically extends along several vertebrae, and it most commonly affects the lower or middle back. An open sac comes through the spinal defect opening, and contains part of the spinal cord, cerebrospinal fluid (CSF), and meninges (the protective membranes that cover the brain and spinal cord).
Myelomeningocele can cause serious complications depending on where the opening is along the spine. These problems can be physical, such as leg weakness or paralysis, or cognitive, such as learning, social and emotional issues.