Defective development within any part of the spinal cord refers to which condition?

• A. Spina bifida
• B. Anencephaly
• C. Cerebral palsy
• D. Poliomyelitis

Answer: (A)

Spina bifida is a neural tube defect where the spine doesn’t form properly because the vertebral arches fail to fuse during early development. This results from defective development in the spinal region, where the spinal cord and surrounding structures don’t close or form correctly. The condition ranges from occult forms, where the defect is hidden, to cystic forms like meningocele or myelomeningocele, where protective coverings or the cord itself may protrude.

In contrast, anencephaly is a failure of brain development due to incomplete cranial neural tube closure, so it affects the brain rather than the spinal region. Cerebral palsy is a motor disorder arising from early brain injury or malformation, not a primary spinal defect. Poliomyelitis is a viral infection that damages motor neurons in the spinal cord, also not a defect of spinal development. Hence, defective development within the spinal area best aligns with spina bifida.