Down Syndrome and Hypotonia

What is Down Syndrome?

A child with Down syndrome has an extra, critical portion of chromosome 21 present in all or some of their cells. This additional genetic material alters the course of development and causes the characteristics associated with Down syndrome. 


  • A round face with a flat profile and small nose and mouth
  • A large tongue that may protrude from the mouth
  • Almond-shaped eyes with skin that covers the inner eye (epicanthus folds)
  • White flecks in the coloured part of the eyes (Brushfield spots)
  • Small ears
  • A small head that’s somewhat flat in the back (brachycephaly)
  • Short neck
  • Clinodactyly: A single crease across the palm of each hand (normally there are two), short stubby fingers, and a pinky finger that curves inward
  • Small feet with a larger than normal space between big and second toes
  • Short, stocky build
  • Low muscle tone: Infants with Down syndrome often appear “floppy” due to a condition called hypotonia. 

What is Hypotonia?

Simply put, hypotonia is the decreased level of muscle tone. It leaves your child’s muscles feeling too relaxed. That’s why kids with low tone are sometimes compared to ragdolls.

But don’t confuse tone with strength. Your child isn’t weak. What he or she needs is stability, not necessarily strength.

What are the symptoms?

Though hypotonia can and often does improve with age and physical therapy, most children with Down syndrome typically reach developmental milestones—sitting up, crawling, and walking—later than other kids. Low muscle tone may contribute to feeding problems and motor delays. Toddlers and older kids may have delays in speech and in learning skills such as feeding, dressing, and toilet training.

As we know, kids with Down syndrome are most of the time late walkers. Pronation (also called flat feet) is a common cause of walking problems. This occurs when an ankle rolls inward, causing the foot’s arch to shrink or disappear completely. This throws your child out of alignment, causing a chain reaction up the body. Although flat feet are fairly common when kids first learn to walk, pronation that is excessive and prolonged can lead to problems down the road. 

Common hypotonia symptoms include:

  • Hypermobility
  • Poor posture
  • Breathing difficulties
  • Feeding problems
  • Delayed speech
  • Walking with a wide base
  • Poor reflexes

What are the treatment options for hypotonia?


Custom-made orthotics are an excellent complement to physical therapy. These little braces help keep your child’s body in proper alignment as he or she learns, develops, and gains strength.

One orthotic solution in particular, the Surestep SMO, revolutionised the treatment of hypotonia. With uniquely flexible plastic, a focus on compression, and an innovative design, it’s effective and unlike any other option.


Inserts that slip into shoes seem like the easy, ideal solution. From the outside, it looks like a significant improvement because the arch of the foot is pushed up. But this fails to address the fact that pronation starts in the heel, not the arch. And if your child’s pronation is more than typical, they’ll simply pronate on top of the insert.

Physical Therapy

PT is an excellent way to help strengthen muscles and develop motor skills. But it won’t fix the alignment, which makes it just half of the solution. And even if your physical therapist spends an hour with your child each week, that leaves 167 hours unattended.


Taking a “wait and see” approach is common, and the self-reliant optimism is admirable. But it risks further delays down the road. If your child hasn’t developed a strong base, further complications can pop up as he or she gets bigger.

Overall, the goal of treatment isn’t just to get your child walking. It’s to set them up for success both today and tomorrow. If left untreated, that poor alignment in childhood can lead to pain and fatigue later in life.

So even if your child who has Down syndrome and hypotonia is reaching milestones, discussing treatment options is an investment in his or her future.