Which clinical feature is commonly associated with spina bifida occulta?

Which clinical feature is commonly associated with spina bifida occulta?

• A. Midline tuft of hair on the overlying skin
• B. Protruding sac containing meninges
• C. Nerve tissue fully exposed
• D. Visible spinal gap

Answer: (A)

A midline tuft of hair over the lower back is a classic skin sign of spina bifida occulta. This condition involves a defect in the vertebral arches (usually in the lumbosacral region) with no herniation of meninges or neural tissue, so there’s no open sac or exposed nerves. The hair tuft reflects an underlying closed or occult dysraphism, meaning the spinal defect is hidden under the skin rather than visibly protruding. The other scenarios describe open or cystic spinal defects. A protruding sac containing meninges fits a meningocele, where the protective coverings protrude through a bony defect. Nerve tissue fully exposed indicates an open neural tube defect like myelomeningocele, where neural elements are exposed outside the body. A visible spinal gap points to spina bifida aperta, another open defect. In occult spina bifida, you wouldn’t typically see an external sac or obvious gap, but you may notice a skin marker such as a tuft of hair, dimple, patch of pigment, or lipoma.

A midline tuft of hair over the lower back is a classic skin sign of spina bifida occulta. This condition involves a defect in the vertebral arches (usually in the lumbosacral region) with no herniation of meninges or neural tissue, so there’s no open sac or exposed nerves. The hair tuft reflects an underlying closed or occult dysraphism, meaning the spinal defect is hidden under the skin rather than visibly protruding.

The other scenarios describe open or cystic spinal defects. A protruding sac containing meninges fits a meningocele, where the protective coverings protrude through a bony defect. Nerve tissue fully exposed indicates an open neural tube defect like myelomeningocele, where neural elements are exposed outside the body. A visible spinal gap points to spina bifida aperta, another open defect. In occult spina bifida, you wouldn’t typically see an external sac or obvious gap, but you may notice a skin marker such as a tuft of hair, dimple, patch of pigment, or lipoma.