neuromuscular disorders in children

Question 1

describe lower motor neurons

Answer 1

starts from anterior horn cells in spinal cord
comprised of cell bodies and axons all the way to NMJ
carries on to the muscle fibres

Question 2

when to suspect neuromuscular disorders

Answer 2

• baby floppy from birth
• slips from hands when you pick them up
• lack of spontaneous limb movements
• alert infants but less motor activity
• delayed motor milestones
• able to walk but frequent falls and clumsiness

Question 3

what is the gower’s sign

Answer 3

indicates weakness in proximal hip muscles - pelvic girdle and lower limb weakness

lie on back up then get up as quickly as possible - process of getting up in photo

Question 4

what does Gower’s sign indicate

Answer 4

Duchenne muscular dystrophy

Question 5

what causes Duchenne muscular dystrophy and who does it occur in

Answer 5

1/ 3500 male infants

Xp21 - dystrophin gene (x linked)

Question 6

features of Duchenne muscular dystrophy

Answer 6

delayed motor skills and may walk late

symmetrical proximal weakness - waddling gait, calf hypertrophy, Gower’s sign +ve

elevated creatinine kinase levels - >1000

cardiomyopathy

resp involvement in teens

Question 7

evidence of muscle weakness in Duchenne muscular dystrophy

Answer 7

Question 8

facial muscle weakness - myopathic facies

Answer 8

• lack of muscle tone and power around the mouth
• open mouth and tented lip appearance
• drooped eyelids
  
  • can’t maintain head control

Question 9

what is myotonia

Answer 9

inability for the muscle to relax after contraction

Question 10

what is Charcot-Marie-Tooth disease

Answer 10

• lack of muscle in feet, high arch, claw toes
• hereditary motor-sensory neuropathy

Question 11

anatomical approach to neuromuscular conditions

• where is the site of the lesion
• what is the lesion

Answer 11

• muscle: muscular dystrophies, myopathies - congenital and inflammatory, myotonic syndromes
• NMJ: myasthenic syndromes
• nerve: hereditary or acquired neuropathies
• anterior horn cell: spinal muscular atrophy

Question 12

neuropathy vs myopathy

Answer 12

NEUROPATHY:

• site of weakness: distal
• sensory: may have concomitant sensory symptoms and signs
• reflexes: lost early
• fasciculation: may be present
• contractures: not a feature
• myocardial dysfunction: not a typical feature

MYOPATHY:

• site of weakness: usually proximal
• sensory: usually pure motor
• reflexes: preserved till late
• fasciculation: not typical
• contractures: present
• myocardial dysfunction: may can accompanying cardiac dysfunction w/ muscle dystrophies