Neural tube defects occur due to interference with cranial or caudal closure during embryological development between 3-4 weeks. Risk factors include genetic and environmental influences. Neural tube defects are classified as open spina bifida, where the spinal cord and meninges are exposed through an opening in the vertebral column, or occult spina bifida, where defects are hidden below the skin surface and can include tethered cord, dermal sinus, lipoma of the cord, diastematomyelia, or thickened filum terminal. Clinical features of neural tube defects include weakness, sphincter disturbances, back pain, scoliosis, sensory deficits, and cutaneous signs.

1. Clinical features of neural tube defects Embryology *Neural Groove dorsal aspect of the embryo3-4 w *Neural Tube

3. Interference with cranial closure (anencephaly or encephalocel Failure of caudal closure leads to meningeocele or meningeomyelocel

6. Risk factors Prenatal influence ,including familial factors, are paramount in each abnormality, especially in the latter Microcephaly may be caused by irradiation or exposure to toxins, while megalencephaly may be associated with neurofibromatosis ,achondroplasia or cerebral gigantism. Familial

8. Opened SB

19. CLINICAL FEATURES WEAKNES SPHINCTERIC DISTURBANCE PAIN IN THE BACK SCOLIOSIS SENSORY DEFICITS CUTANOUS SIGNES