Charcot-Marie-Tooth (CMT)

CMT is the most common inherited neurological condition in the world. It’s also highly likely that it’s something you’ve never heard of. CMT awareness month this October aims to change that! 

Charcot-Marie-Tooth (CMT) Disease is a group of inherited disorders estimated to affect one in 2,500 people that cause nerve damage, mostly in the arms and legs (peripheral nerves). These nerves are responsible for passing on commands from the brain to the muscles (motor nerves) and information to the brain about sensations, such as pain, heat, cold, touch, importantly for balance – where your joints are in space (sensory nerves). When these are damaged, people are said to have a neuropathy. CMT disease is also called hereditary motor and sensory neuropathy.

Because of this nerve damage, people with CMT may find that some of their muscles become slowly weaker over the years, particularly in their feet and hands. Some find that feeling becomes dull, or numb, in the same areas. You may also experience loss of sensation and muscle contractions, and difficulty walking. Foot deformities such as hammertoes and high arches also are common. Symptoms usually begin in the feet and legs, but they may eventually affect your hands and arms.

SYMPTOMS

The symptoms of CMT usually start to appear between the ages of five and 15, although they sometimes do not develop until well into middle age or later. CMT is a progressive condition. This means the symptoms slowly get worse, making everyday tasks increasingly difficult.

People with CMT may have:

• Muscle weakness in their feet, ankles, legs and hands

• Decreased sensation or a loss of feeling in your legs and feet

• An awkward way of walking (gait)

• Highly arched or very flat feet

• Loss of muscle bulk in legs and feet

• Curled toes (hammertoes)

• Decreased ability to run

• Difficulty lifting the foot at the ankle (footdrop)

• Frequent tripping or falling

CAUSES

CMT is caused by an inherited fault in one of the many genes responsible for the development of the peripheral nerves. This fault means the nerves become damaged over time. A child with CMT may have inherited the genetic fault responsible for the condition from one or both of their parents.

There’s no single faulty gene that causes CMT. There are many types of CMT that are caused by different genetic faults and these can be inherited in several different ways. The chances of passing CMT to your child depend on the specific genetic faults you and your partner carry.

TREATMENT

CMT is not life threatening and most people with the condition have the same life expectancy as a person without the condition. But it can make everyday activities very difficult. Living with a long-term progressive condition can also have a significant emotional impact.

There’s currently no cure for CMT. But treatments can help relieve symptoms, aid mobility, and increase independence and quality of life for people with the condition.

These treatments may include:

• Physiotherapy and certain types of exercise

• Occupational therapy

• Walking aids

In some cases, surgery may be needed to correct problems such as flat feet and muscle contractures, where muscles shorten and lose their normal range of movement.

For more details and how to support CMT Awareness Month, visit cmt.org.uk