Excessive limpness in infants, also known as floppy infant syndrome. Hypotonic babies cannot hold their limbs up against gravity and so tend to lie flat with their arms and legs splayed. Hypotonia may be caused by Down’s syndrome or hypothyroidism and may be
an early feature of cerebral palsy.
It occurs in disorders of the spinal cord, such as Werdnig–Hoffman disease, and in some children who have muscular dystrophy.
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