Dwarfism

What is dwarfism?

Dwarfism is a condition where a person is unusually short.

Short stature is generally defined as an adult height of 147cm (4 feet and 10 inches) or less. However, most people with dwarfism only grow to 122cm (4 feet).

Most people prefer the term ‘short stature’, while others are happy to be called ‘little people’ or ‘dwarfs’.

What are the symptoms of dwarfism?

There are 2 main types of dwarfism:

1. proportionate short stature — a general lack of growth but with normal body proportions
2. disproportionate short stature — your arms and legs are smaller than normal

Proportionate short stature

People with proportionate dwarfism usually have a medical condition that affects their overall growth and development.

They are usually slow to grow and have delayed sexual development.

Disproportionate short stature

People with disproportionate dwarfism often have an average-sized torso with short arms and legs. They often have a large head.

Most people with disproportionate dwarfism have normal intelligence.

Other symptoms of short stature

Other signs and symptoms vary across the spectrum of disorders.

Most people with dwarfism don’t have serious health problems and have a normal life expectancy. People with dwarfism go to school or work just like other people.

Often the biggest challenge is being accepted and included in everyday society.

What causes dwarfism?

Many different conditions result in dwarfism or restricted growth. These are often genetic conditions, but sometimes the cause is unknown.

Causes of proportionate short stature

The most common cause of proportionate short stature is being born to small parents. However, your doctor may still want you to have tests to make sure that there are no other causes of your short stature.

Proportionate short stature can also be caused by:

• your body not producing enough growth hormone
• certain genetic syndromes — such as Noonan syndrome, Prader-Willi syndrome and Turner syndrome

Causes of disproportionate short stature

Achondroplasia is the most common cause of disproportionate short stature. It causes poor bone growth, resulting in short upper arms and thighs.

Many children with achondroplasia have parents of normal height — 8 out of 10 people with achondroplasia are the first in their family with the condition.

Other common genetic conditions that cause disproportionate short stature are:

• diastrophic dysplasia
• hypochondroplasia
• osteogenesis imperfecta
• pseudoachondroplasia
• spondyloepiphyseal dysplasia congenita

When should I see my doctor?

Sometimes dwarfism can be diagnosed before your child is born or at birth. At other times, growth problems become obvious as your child gets older.

How is dwarfism diagnosed?

To diagnose dwarfism, your doctor will usually:

• take a full medical and family history
• collect measurements, such as height and weight
• do some blood tests (sometimes including hormone tests)
• do imaging, such as x-rays, an MRI scan or a CT scan

If one or both parents have a family history of a condition that causes short stature, your baby can be tested for this during pregnancy (prenatal diagnosis).

Some people might be asked to have genetic testing.

How is dwarfism treated?

Growth hormone

Treatment with growth hormone injections may help a child with restricted growth grow more than they otherwise would.

This treatment is covered under the Pharmaceutical Benefits Scheme.

Leg lengthening

A leg-lengthening operation is sometimes used to treat disproportionate short stature. The leg bone is broken and fixed to a special frame. This allows new bone to form between the 2 broken ends of bone.

It can sometimes cause a large increase in height. However, it’s a long treatment and there is a risk of complications. Further, its safety and effectiveness isn’t fully understood.

Vosoritide medicine

In May 2023, the Australian Government added the medicine vosoritide to the Pharmaceutical Benefits Scheme.

Vosoritide can be used to treat achondroplasia. It works by encouraging new bone growth in children who are still growing.

Emotional wellbeing

People with dwarfism may benefit from emotional support. People of short stature are often misunderstood. This hasn’t been helped by the often stereotypical portrayal of dwarfs in movies and the entertainment industry.

Connecting with others with short stature may be helpful. Contact the Short Statured People of Australia organisation for more information.

Can dwarfism be prevented?

Because there are many causes of dwarfism, including new genetic mutations, it can’t be prevented.

What are the complications of dwarfism?

Complications of dwarfism can vary greatly.

People with disproportionate short stature may have a number of physical health problems, such as:

• back pain
• increased wear and tear on your joints leading to pain and disability
• abnormal skull growth — which can cause problems with jaw growth and teeth over-crowding
• frequent ear infections leading to hearing loss
• sleep apnoea