Hypotonia Overview
Learn About Hypotonia
Hypotonia means decreased muscle tone.
Decreased muscle tone; Floppy infant
Hypotonia is often a sign of a worrisome problem. The condition can affect children or adults.
Infants with this problem seem floppy and feel like a "rag doll" when held. They rest with their elbows and knees loosely extended. Infants with normal tone tend to have flexed elbows and knees. They may have poor head control. The head may fall to the side, backward, or forward.
Infants with normal tone can be lifted with the adult's hands placed under the armpits. Hypotonic infants tend to slip between the hands.
Muscle tone and movement involve the brain, spinal cord, nerves, and muscles. Hypotonia may be a sign of a problem anywhere along the pathway that controls muscle movement. Causes may include:
- Brain damage, due to lack of oxygen before or right after birth, or problems with brain formation
- Disorders of the muscles, such as muscular dystrophy
- Disorders that affect the nerves that supply muscles
- Disorders that affect the ability of nerves to send messages to the muscles
- Infections
Genetic or chromosomal disorders, or defects that may cause brain and nerve damage include:
- Down syndrome
- Spinal muscular atrophy
- Prader-Willi syndrome
- Tay-Sachs disease
- Trisomy 13
Other disorders that can lead to the condition include:
- Achondroplasia
- Being born with hypothyroidism
- Poisons or toxins
- Spinal cord injuries that occur around the time of birth
Take extra care when lifting and carrying a person with hypotonia to avoid causing an injury.
Your health care provider will do a physical exam including a detailed examination of the nervous system and muscle function.
In most cases, a neurologist (specialist in brain and nerve disorders) will help evaluate the problem. Geneticists may help diagnose certain disorders. If there are also other medical problems, a number of different specialists will help care for the child.
Which diagnostic tests are done depends on the suspected cause of the hypotonia. Most of the conditions associated with hypotonia also cause other symptoms that can help make the diagnosis.
Many of these disorders require ongoing care and support. Physical therapy may be recommended to help children improve their development.
Laurence Faivre practices in Dijon, France. Mr. Faivre is rated as an Elite expert by MediFind in the treatment of Hypotonia. His top areas of expertise are Cohen Syndrome, Achalasia Microcephaly Syndrome, Microcephaly, Hypotonia, and Orchiectomy.
Bertrand Isidor practices in Nantes, France. Mr. Isidor is rated as an Elite expert by MediFind in the treatment of Hypotonia. His top areas of expertise are Achalasia Microcephaly Syndrome, Microcephaly, Hypotonia, and Cortical Dysplasia.
Carsten Bonnemann is a Pediatric Neurologist and a Pediatrics provider in Philadelphia, Pennsylvania. Dr. Bonnemann is rated as an Elite provider by MediFind in the treatment of Hypotonia. His top areas of expertise are Tubular Aggregate Myopathy, Congenital Fiber-Type Disproportion, X-Linked Myotubular Myopathy, Hypotonia, and Gastrostomy.
Background: Congenital myopathies (CM) are genetic disorders that can cause decreased muscle tone and muscle weakness. Most CMs in the United States are related to the ryanodine receptor 1 (RYR1) gene. Researchers need more natural history data to learn about these CMs in children and adults.
Summary: Obstructive sleep apnea (OSA) is a prevalent medical condition with important implications for overall health and quality of life in both children. Therefore, it is important to treat OSA early and effectively. Children with Down syndrome and Prader-Willi syndrome have many predisposing factors for OSA, including mouth breathing, narrow upper airways resulting from craniofacial abnormalities, and ...
Published Date: December 31, 2023
Published By: Anna C. Edens Hurst, MD, MS, Associate Professor in Medical Genetics, The University of Alabama at Birmingham, Birmingham, AL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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