Meningomyelocele

A congenital deformity.

The pushing forward of part of the meninges and spinal cord through a gap in the spine.

Meningomyelocele is a neural tube defect resulting in the herniation of the meninges and spinal cord through a vertebral defect. Neural tube defects (NTDs) refer to a group of malformations of the spinal cord, brain, and vertebrae, the most common being spina bifida, which is characterized by a split of a section of the vertebral arches. When spina bifida is associated with both a meningeal sac and a malformed spinal cord, the condition is called meningomyelocele (or myelomeningocele). Most meningomyeloceles are open, meaning that a portion of the spinal cord is visible at birth as an open sac overlying part of the vertebral column; Pediatric Database [PEDBASE], 1994).

A severe form of spina bifida, a neural tube defect. Meningomyelocele occurs when the bones of the spine do not form completely, leaving the spinal canal incompletely closed. The protrusion of the spinal cord affects neurological function below the site of the defect. Most defects occur in the lowest areas of the back (lower lumbar or sacral areas), because in normal development they are the last parts of the spine to close. Symptoms of muscle weakness, paralysis, loss of sensation, and impaired bladder and bowel control are caused by damage to the spinal cord. Symptoms also include the presence of a sac protruding from the spinal cord on the back of a newborn baby. The exposed spinal cord is susceptible to infection, especially meningitis.