GuidelinesOther guideline
The Floppy Infant (Distinguished from the Weak Child)
The Floppy Infant (Distinguished from the Weak Child)
It is important in the case of the floppy infant to distinguish whether the child is weak or hypotonic. It is not always possible, but it does help to locate the level of the lesion.
A practical approach is to divide floppy infants into 2 broad categories:
- Central Hypotonia- the setting is usually one of a brain abnormality or injury, with a more global involvement of cerebral function.
- Peripheral Hypotonia- this is usually due to pathology from the anterior horn cell and distally, where higher functions are usually intact and the infant is alert and visually responsive.
Clinical features to focus on
- Detailed history: recent infection/family history/milestones/birth history. Intra-uterine movements.
- Course of illness: Recent and rapid onset of weakness: see below
- Immunisations: Polio
- Head circumference
- Examine cranial nerves
- Deep tendon reflexes: if intact rules out lower motor neurone lesions
- Signs of rickets
- Signs of hypothyroidism
- Dysmorphic features
- Malnutrition
- Systemic disease
Causes
Lower motor neuron intact
Acute illness
- Neonatal insults- IVH’s or HIE.
- Cerebral Palsy
- Down’s Syndrome
- Nutrition – PEM/Rickets
- Hypothyroidism
- Connective tissue disorder
- Cerebral degenerative conditions
Lower motor neuron or muscle lesions
SMA
- Poliomyelitis
- Congenital Myasthenic syndromes
- Hypokalaemia
- Peripheral Neuropathies
- Congenital Myopathies
- Botulism