Hypotonia is decreased muscle tone.
Considerations: Hypotonia is often a sign of a worrisome problem. It may be a sign of a central nervous system problem, genetic disorder, or muscle disorder.
It can affect children or adults.
Infants with hypotonia seem floppy and feel like a "rag doll" does when held. They rest with their elbows and knees loosely extended, while infants with normal tone tend to have flexed elbows and knees. Head control may be poor or absent, with the head falling to the side, backward, or forward.
Infants with normal tone can be lifted with the parent's hands placed under the armpits, while hypotonic infants tend to slip between the hands as the infant's arms rise unresistingly upward.
What to expect at your health care provider's office: The health care provider will perform a physical exam and ask questions about the patient's family and medical history, including:
- When did you first notice the decreased muscle tone?
- Was it seem at birth?
- Did it develop suddenly or slowly?
- Have you ever noticed a pattern to the behavior (is it always the same or is it worse at certain times)?
- What other symptoms are present?
The physical examination will probably include a detailed nervous system and muscle function examination.
Diagnostic tests will vary depending on the suspected cause of the hypotonia. Most of the conditions associated with hypotonia also cause other symptoms that together will suggest a particular disorder.