Which form of spina bifida is the most common and least severe, without protrusion of the spinal cord or meninges?

• A. Spina bifida cystica
• B. Spina bifida meningomyelocele
• C. Spina bifida occulta
• D. Spina bifida myelomeningocele

Answer: (C)

Spina bifida occulta represents a defect in the vertebral arch without any protrusion of the spinal cord or meninges. Because there is no sac or exposed neural tissue, it typically causes no or only mild symptoms and is often discovered incidentally. It’s the most common and least severe form, sometimes described as hidden spina bifida, with signs that may include a skin marker over the spine, such as a tuft of hair or a small dimple.

In contrast, forms that involve protrusion—such as meninges with cerebrospinal fluid (a meningocele or cystica) or both meninges and spinal cord tissue (myelomeningocele)—tend to have more significant neurological implications and require surgical repair and ongoing care.