- Muscle tone refers to the resting tension of a muscle when it’s relaxed and supports the body position.
- Muscle tone is regulated by signals that travel from the brain through nerves and tell the individual muscles to contract a small amount.
- Low tone or hypotonia (the medical term) makes it harder for children to move against gravity.
- Parents may first notice hypotonia in their baby as they can feel “floppy” in their neck, trunk, arms or legs and this floppiness is due to low muscle tone.
- Children with low tone may take longer to reach their developmental milestones such as rolling, lifting their head, sitting, crawling and walking.
Hypotonia can be mild, moderate or severe and affect different areas or sides of the body. It can be difficult to tell initially how affected the child is, but as the child grows and attempts to learn gross motor skills it can be easier to identify the muscles affected by low tone.
Muscle tone is different to muscle strength although it can be difficult to control the affected muscles. Hypotonia can result in difficulty with muscle control and it is this control that allows us to regulate the force, speed and timing of our movements.
Diagnosis
Hypotonia may be identified by a parent or health professional by observing the child and completing a physical examination. They would feel hardly any resistance when they move their arms or legs which would indicate low tone. The child would then be referred to a health professional who would then take a detailed medical history, possibly request blood tests and scans to discover the cause of the low muscle tone.
Cause
Hypotonia is a symptom and not a condition and can be caused by a number of conditions such as;
- Cerebral Palsy
- Neurological conditions
- After serious infections (such as meningitis or encephalitis)
- Babies born prematurely (because their muscles aren’t fully developed by the time they’re born)
- Genetic conditions (such as Down’s syndrome or Prader-willi syndrome)
It can also occur in older children or adults however, this is less common
Prognosis
The prognosis of a particular case of hypotonia depends largely on the cause of the low tone, if the condition is progressive or degenerative the prognosis will be different to a non-progressive condition. In many cases a child’s muscle tone will improve over time and therapeutic exercises and activities will help them master motor skills in spite of their abnormal tone. As the child grows, develops and receives therapy the affects of low muscle tone will become less noticeable.
Treatment
Early intervention is important if your child is not meeting their developmental milestones and you can seek advice and referrals from your health visitor, GP, paediatrician, physiotherapist, speech and language therapy and occupational therapist.
The main focus of physical therapy is to optimize postural control, improve motor control and overall body strength in children with hypotonia. Therapy should be specific to the individual child and aim to help them reach their developmental milestones with simple exercises and techniques to help them build strength, control, co-ordination, encourage correct movement patterns, confidence and independence.
If you have just received this diagnosis or suspect low tone, remember there are lots of simple exercises that can help a young child work towards their developmental milestones. The most important thing to do is to ask for professional help and guidance from NHS or private professionals if needed because they are there to help and support you.
For more information visit:
NHS Website – Hypotonia
What is Cerebral Palsy? – blog post
