What is Charcot-Marie-Tooth disease?

Charcot-Marie-Tooth disease (CMT) is a group of genetic conditions that affect your nervous system. CMT is sometimes called hereditary motor and sensory neuropathy (HMSN).

In Australia as many as 1 in 2,500 people may have CMT.

The disease is named after the 3 doctors who first described it — Jean-Martin Charcot, Pierre Marie and Howard Henry Tooth.

CMT is a progressive condition, which means it gets worse over time. It affects people in different ways. CMT is not life-threatening. Most people with the disease have the same life expectancy as someone without the condition.

What are the symptoms of Charcot-Marie-Tooth disease?

Most people with CMT first show signs of the condition by the age of 20 years.

The most common features are weakness and atrophy (loss of muscle bulk) of the lower legs and feet.

Problems usually start in the muscles that support your feet, then later in your hands.

Symptoms vary from person to person, but can include:

• difficulties with balance
• difficulty finding well-fitting shoes due to high foot arches
• problems walking
• twisting of your ankles
• feet slapping

Features are normally symmetrical (happen on both sides of your body).

The most distant muscles are affected first. So, your feet will be affected before your ankles. Which are in turn affected before your hands.

What causes Charcot-Marie-Tooth disease?

CMT is caused by mutations (faults) in your genes. These cause your peripheral nerves (those outside of your brain and spinal cord) to become damaged.

These nerves carry messages from your brain to the rest of your body. They connect your body’s muscles, joints and skin to your spinal cord and brain. The peripheral nerves carry both sensations and commands for movement.

If you have CMT, your peripheral nerves have trouble sending the signals they need to.

There are many different types of CMT. They are all caused by genetic mutations (or errors).

Family history is the only known risk factor for the condition.

When should I see my doctor?

See your doctor if you are concerned that you may have Charcot-Marie-Tooth disease.

How is Charcot-Marie-Tooth disease diagnosed?

Your doctor will ask about your symptoms, your medical history, and any family history of genetic diseases.

If your doctor thinks you might have a neurological disorder, they will arrange for you to have some tests. These will look for problems such as slow or weak nerve signals.

Genetic tests may also be done to try to work out if you have CMT, and which type of CMT you have.

How is Charcot-Marie-Tooth disease treated?

While there is no cure for CMT, there are several treatments that can help you with the condition.

There are many therapies that can help.

• Physiotherapy and exercise can help maintain movement, strength, flexibility and a healthy weight.
• Occupational therapy can offer devices and strategies that will help you with everyday tasks.
• Orthotics and braces to help you stay mobile.
• Surgery to correct bone differences.
• Counselling to help manage pain and tiredness.

Low-impact exercises, such as cycling and swimming, can help increase your energy levels and reduce fatigue and pain. Physiotherapy can also be helpful.

Both bracing and orthopaedic surgery on your feet can improve your mobility and independence.

Bracing

People of all ages with CMT should be assessed for appropriate bracing. Bracing can improve your quality of life. Good bracing can also delay or remove the need for orthopaedic surgery.

It’s important that the right brace is fitted to each person. Gait and mobility aids should be prescribed by a qualified health professional.

Orthopaedic surgery

You may need orthopaedic (bone) surgery at some point. This may be:

• to correct foot difference associated with CMT
• for complications, such as a knee or hip replacement due to osteoarthritis

Can Charcot-Marie-Tooth disease be prevented?

Charcot-Marie -Tooth disease can’t be prevented as it’s caused by mutations (changes) to your genes.

Complications of Charcot-Marie-Tooth disease

Possible long-term complications of CMT are:

• pain
• osteoarthritis

Resources and support

The Charcot-Marie-Tooth Association Australia offers resources and support for people with this condition.

To learn more about genetic disorders, you can visit healthdirect's genetic disorders guide. You can also read about genetic counselling.

If you want to know more about Charcot-Marie-Tooth disease, you can call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.