Which form is the most common among spina bifida aperta?

• A. Meningocele
• B. Myelomeningocele
• C. Myeloschisis
• D. Occulta

Answer: (B)

Spina bifida aperta refers to open spinal defects where neural tissue or meninges are exposed. The form that most commonly presents in this category is myelomeningocele, in which both meninges and the spinal cord protrude through a vertebral defect. This is far more frequent than myeloschisis, where neural tissue is directly exposed without a covering, and more common than meningocele, where only meninges and CSF herniate without neural tissue. Occulta, by contrast, is a closed, non-aperta defect and is not part of spina bifida aperta. Myelomeningocele is the classic, most common open form and is typically associated with significant neurological involvement and related complications.