4. What is neurapraxia?
Correct answer: Damage to the nerve fibres without loss of continuity of the axis cylinder; this is analogous to concussion within the central nervous system. The conduction along the fibres is interrupted for only a short period of time. Recovery…
3. How can peripheral nerves be injured in general?
Correct answer: Laceration, stretching (traction) or compression.
2. What are the three degrees of peripheral nerve injury?
Correct answer: (1) Neurapraxia.(2) Axonotmesis.(3) Neurotmesis.
13. What are the clinical features of spina bifida occulta?
Correct answer: This is usually an incidental finding noted on X-ray. When overlying skin changes (dimple, hair tuft, lipoma, sinus) are present, the cord beneath may be tethered to the skin by a fibrous band, and, as the child grows…
12. What should the astute clinician look for in the overlying skin in the case of spina bifida?
Correct answer: Tuft of hair; a dimple; an overlying lipoma.
11. Why is does hydrocephalus almost always coexist with a myelomeningocele?
Correct answer: This is because of an Arnold–Chiari malformation, in which the cerebellar tonsils descend below the foramen magnum with consequent obstruction of the cerebrospinal fluid pathway.
10. What are the clinical features of spina bifida?
Correct answer: These defects are particularly common in the lumbosacral area, although any part of the spine may be involved. There may be an associated overlying lipoma, tuft of hair or skin dimple, which may be an important clue to…
9. What has been the result of antenatal screening for spina bifida?
Correct answer: The number of infants born with severe spinal abnormalities has, in consequence, greatly declined.
8. How can spina bifida be screened for antenatally?
Correct answer: Antenatal screening (presence of high levels of ∝-fetoprotein in the amniotic fluid and ultrasound) enables a high degree of accuracy in intrauterine diagnosis of neural tube defects, and gives the opportunity for termination of the pregnancy.
