Hypotonic infant Flashcards
Tone
passive resistance to muscle movement- cannot be changed by voluntary control or exercise
Weakness
power of strength
Hypotonia
lowered resistance to passive movement when alert but not stimulated
differs from strength (weakness)
differs from fatigability
weak infants are always hypotonic
hypotonic infants may have normal strength
Causes of hypotonia
central nervous abnormalities
- chromosome disorders
- metabolic diseases- sepsis
- spinal cord injuries
- cerebral dysgenesis
- hypoxic-ischemic injuries- obtained during birth
motor neuron- anterior horn cells
- spinal muscular atrophies
- traumatic myelopathy
nerve
- no myelin or degeneration
- preservation of intelligence- no cognitive, just motor
muscle
- congenital myopathy
- muscular dystrophy
- central core disease/fibre myopathies
neuromuscular junction
- infantile botulism
- congenital and transient myasthenia gravis
History for hypotonia includes:
history of pregnancy
- term
- TORCH exposure or infections
- hx of spontaneous abortions
delivery
- hx of hypoxia of mother
- abnormal physical exam at birth (dysmorphic, arthrogryposis)
- APGAR
post natal period
- milestones- Hx of motor delay with normal socialization decreases likelihood of CNS
- clinical course (increase in tone vs. progressive weakness)
- ability to feed
family hx
premature death
APGAR scoring system
Activity (tone)
0- absent
1- flexed arms and legs
2- active
Pulse
0- absent
1- bellow 100
2- over 100
Grimace (reflexes)
0- floppy
1- minimal response
2- prompt response to stimulation
Appearance (color)
0- blue, pale
1- pink body, blue extremities
2- pink
Respiration
0- absent
1- slow and irregular
2- vigorous cry
taken at 5, 10, & 30 min
score out of 10
Motor milestones
6 w- smiles
2/3 m- head lifted RED- lack of social response or vocalization
5-6- roll over
6- sit, finger feed self RED- poor head control, floppiness, not reaching
9m- crawls- sits steadily when unsupported and pivots around
11-12- stand up without assistance- RED not communicating by gestures (pointing) and not bearing weight on legs
Frog leg posture
abnormal at any age
Tone is maintained by
cerebellar at the red nucleus, basal ganglia, and motor strip
damage to cerebellar and motor strip = hypotonia
damage to red nucleus and basal ganglia= hypertonia
Primitive reflex
Moro- startle- head back, arms out then cry
6m
Tonic neck- turn head tonic contracture on that side
6-7m
Suck- touch root of mouth
Root- touch side of mouth
Horizontal suspension
attempt to lift head
flexes arms and legs
abnormal= draped like cloth
Vertical suspension
no pull through
flexion at knee, hip, ankle
Traction response
flex of arm
holds head
infant tries to help
measure of postural tone
Down syndrome- trisomy 21
microgenia (small chin) macroglossia (large tongue) simian crease (hand) eye folds thin upper lip railroad track ears upturned nose flat nasal bridge congenital heart defects otitis media short stature
Prader-Willi- deletion
narrow temple distance and nasal bridge almond shaped eyes thin upper lip overweight developmental delay
