Decreased muscle tone in infants, usually indicating the presence of genetic, muscle, or central nervous system disorders. Infants who are hypotonic feel floppy when held, and when at rest, they lie with their limbs loosely extended, unlike infants with normal muscle tone, who tend to flex their elbows and knees.
Hypotonia, also referred to as floppy infant syndrome, describes a condition in which infants exhibit extreme limpness. Babies with hypotonia lack the ability to hold up their limbs against gravity, and as a result, they tend to lie flat with their arms and legs spread out.
Hypotonia can be a result of various conditions including Down’s syndrome or hypothyroidism, which is characterized by insufficient production of thyroid hormones. It could also be an early sign of cerebral palsy. Spinal cord disorders, like Werdnig-Hoffman disease, as well as some cases of muscular dystrophy in children, can also lead to hypotonia.