What Is Charcot-Marie-Tooth (CMT)? Causes, Symptoms and Progression

Many people have never heard of Charcot-Marie-Tooth (CMT), even though it is one of the most common inherited neurological disorders.

It affects the peripheral nerves that control muscles and sensory functions, which means both movement and sensation can be impacted. For many, the diagnosis comes as a shock. However, with the right knowledge, it is possible to live well with CMT.

Charcot-Marie-Tooth is a type of neuropathy, meaning it affects the peripheral nerves. These nerves connect the brain and spinal cord to muscles and skin. When they do not function properly, signals are not transmitted effectively.

The condition is named after the physicians Jean-Martin Charcot, Pierre Marie and Howard Henry Tooth. CMT belongs to a group of disorders known as hereditary motor and sensory neuropathies. This means it is inherited and affects both movement and sensation.

How Common Is Charcot-Marie-Tooth?

Even though many people are unfamiliar with the condition, it is not rare.

Estimates suggest that around 1 in 2,500 to 5,000 people are affected. [1]

The diagnosis is often made late, as early symptoms can be non-specific and easily mistaken for other conditions.

Charcot-Marie-Tooth is caused by genetic mutations.

These mutations affect how certain nerve cells are structured and how they function. There are different types of CMT, such as CMT1, CMT2 and CMTX. They differ in the genes involved and in how the condition develops.

Some mutations damage the myelin sheath, the protective layer around nerve fibers. Others affect the axon, the inner part of the nerve.

In both cases, signal transmission becomes less reliable. Muscles respond more slowly, and sensation in the hands and feet may decrease.[2]

Inheritance in Families

CMT is often inherited in an autosomal dominant pattern.

This means that if one parent is affected, there is about a 50 percent chance that a child will inherit the condition.

There are also autosomal recessive and X-linked forms.

Genetic counseling can help you better understand your individual risk, especially if CMT already runs in your family. It is important to remember that no one is to blame. Genes are not a mistake, but a natural part of human diversity.

Early signs often appear in childhood or adolescence, but they can also develop later in life.

Symptoms usually progress slowly and can vary in severity. [3]

Common symptoms include:

• weakness in the feet and lower legs
• an unsteady gait or frequent tripping
• changes in foot shape, such as high arches or hammer toes
• later involvement of the hands and arms
• numbness or tingling sensations

These symptoms occur because the nerves can no longer properly control the muscles.

How Symptoms May Progress

The course of CMT varies widely.

For some people, the condition remains mild for many years, while others experience more significant limitations.

CMT is a chronic condition, but it is generally not life-threatening.

The progression of CMT can vary significantly.

Many people remain active and mobile for years.[4] The condition usually progresses slowly, and life expectancy is typically normal [5].

What may help in everyday life:

• regular exercise and physiotherapy
• supportive devices such as insoles or orthoses
• early rehabilitation
• patience with yourself

Emotional support and connecting with others can also be very helpful.

What Influences the Progression?

• the specific type of CMT
• your level of physical activity
• early treatment and appropriate therapies [6]

If you notice persistent muscle weakness, foot problems or sensory changes, it is important to seek neurological evaluation.

Diagnosis usually involves several steps:

Typical tests include:

• neurological examination to assess reflexes, strength and sensation
• nerve conduction studies (ENG/EMG) to measure how fast signals travel through the nerves
• genetic testing to confirm the exact type of CMT

Why an Accurate Diagnosis Matters

Many people go through a long journey before receiving a diagnosis.

A clear diagnosis provides certainty, opens up appropriate treatment options and helps in choosing the right supportive devices.[7].

Living with CMT means adapting, but not giving up.

Supportive devices, regular movement and connecting with others can make everyday life much easier.

Charcot-Marie-Tooth is not curable, but it can be managed effectively.

With knowledge, movement and support, it is possible to live a full and active life.

The earlier you understand what is happening in your body, the easier it becomes to cope with the condition.

1. StatPearls - Charcot-Marie-Tooth Disease. NCBI Bookshelf, 2024.
2. European Journal of Human Genetics - Charcot-Marie-Tooth disease, 2009.
3. MedlinePlus - Charcot-Marie-Tooth Disease: Symptoms and Overview. NIH, 2024.
4. OrphanAnesthesia - Charcot-Marie-Tooth disease: Anaesthesia recommendations.
5. HNF - What is CMT? Living and coping with Charcot-Marie-Tooth disease.
6. MDPI (2023) - Physiotherapy and balance interventions for CMT.
7. Gelbe Liste - Charcot-Marie-Tooth Erkrankung - mögliche Therapie, 2023.