What is hypotonia?
According to the National Institute of Neurological Disorders and Stroke, Hypotonia is a medical term used to describe decreased muscle tone. The condition was first described in 1956 among infants who were termed “floppy infants”. Normally, muscles have a very small amount of contraction that gives them a springy feel and provides some resistance to passive movement. It is not the same as muscle weakness, although the two conditions can co-exist. Hypotonia does not affect intellect and the opposite of hypotonia is hypertonia.
As a therapist, the use of this term is becoming more and more common. If you are a parent and this term recently entered your vocabulary, you are probably equal parts concerned and confused.
Today, we would like to clear your doubts and we’ll take a deep dive into the world of hypotonia.
What is muscle tone?
Muscle tone is the amount of tension (or resistance to movement) in muscles. It helps us to hold our bodies upright when we are sitting and standing. Changes in muscle tone are what enable us to move. It also contributes to the control, speed and amount of movement we can achieve.
Low muscle tone is used to describe muscles that are floppy (hypotonia). Children with low muscle tone may need to put more effort to get their muscles moving properly when they are doing an activity. Normally, children with low muscle tone have delays in their gross motor development (e.g. rolling, sitting, walking).
Here is one way you can understand muscle tone better by using the “rubber band method”. Grab a rubber band (or hair tie).
The rubber band represents the amount of tension in muscles while they’re at rest.
Muscles that are too relaxed or too rigid cause a variety of challenges. And they’re not all associated with mobility.
What causes hypotonia?
There is no specific cause to hypotonia. Most of the time it is related to another health problem. There are many causes and here a few are:
- brain damage due to lack of oxygen right before or after birth
- problems with the way the brain formed in the womb
- disorders that affect nerves
- cerebral palsy
- down syndrome
- spinal cord injury
- severe infections
Diagram above is from University of Calgary Blackbook.
If you are not sure if your child has low tone, there are test available.
What are the symptoms if my child has hypotonia?
Hypotonia impacts everyone differently.
This is because:
- Hypotonia can range from mild to severe
- Hypotonia can impact different parts of the body
- Hypotonia can be just one of the symptoms associated with a diagnosis
In general, common symptom categories include:
Kids tend to reach fine and gross motor milestones slower than peers
Kids are seen with increased range of motion and muscle laxity which leads to kids feeling less stable (e.g. kids with flat feet/pronation will have less endurance and poor balance)
Kids with hypotonia are seen to get tired easily and takes extra effort to get an activity done.
What is pronation?
As a therapist, one of the most common signs of hypotonia I’ve noticed is pronation. Parents may first realised that their child’s walking pattern is not stable and is walking with feet wide apart.
Pronation is the inward roll of the ankle that forces a child to stand and walk on the inside of his or her feet.
It may look like it is not a big concern, however, it actually affects your child’s alignment and causes a chain reaction up the body.
How to check?
Have your child stand barefoot and then look from directly behind them. If you see pinky toes but no big toes, your child pronates.
What are the treatment options for hypotonia?
An experienced paediatric physiotherapist will guide your child through activities and experiences that often feels like play. It can help your child to get more control of their movements, improves strength and muscle tone over time.
An experienced paediatric occupational therapist will guide your child through activities and experiences that often feels like play. It can help your child to get fine motor skills, improves strength and muscle tone over time, which are (or will be essential for daily tasks).
An experienced paediatric speech therapist will help with problems breathing, speaking, and swallowing.
Surestep SMOs are braces specifically designed to treat pronation caused by hypotonia.
They gently compresses your child’s feet and ankle, which helps:
- Increase stability
- Improve alignment
- Build confidence
And because they’re custom-made, you’ll first need to get a consultation with us and we will recommend what is best for your child.