Myelomeningocele describes which protrusion?

• A. Meninges only protruding
• B. Spinal cord and membranes protruding through the vertebral column
• C. Brain tissue protruding through the skull
• D. The brain and meninges protruding into the spinal canal

Answer: (D)

Myelomeningocele is a form of spina bifida where both the spinal cord and the meninges protrude through a defect in the vertebral column. This means the neural tissue plus protective membranes herniate outside the body, typically in a sac on the back, which can lead to significant motor and sensory impairment below the level of the defect.

This is different from a meningocele, where only the meninges protrude without the spinal cord, and from conditions involving brain tissue protruding through openings in the skull (encephalocele). The description that best matches myelomeningocele is the one involving the spinal cord and meninges protruding through the vertebral column.