Charcot (shahr-KOH)-Marie-Tooth disease is a group of inherited conditions that cause nerve damage. Inherited conditions pass down through families. This damage mainly is in the nerves of the arms and legs, called the peripheral nerves. Charcot-Marie-Tooth disease also is called hereditary motor and sensory neuropathy.

Charcot-Marie-Tooth disease causes smaller, weaker muscles. It also may cause trouble walking, and loss of feeling in the legs and feet. Some people cannot tense their muscles. Foot issues such as hammertoes and high arches are common. Symptoms most often begin in the feet and legs. But in time, they may affect the hands and arms.

People with Charcot-Marie-Tooth disease most often get symptoms in the teen years or early adulthood. But symptoms also may start in midlife or in the toddler years.

Symptoms of Charcot-Marie-Tooth disease may include:

• Weakness in the legs, ankles and feet.
• Muscle shrinking, called atrophy, in the legs and feet. This can cause the calves to look like an upside-down Champagne bottle.
• High foot arches.
• Curled toes, called hammertoes.
• Not being able to run.
• Trouble lifting the foot at the ankle, called footdrop.
• Clumsy walking.
• Tripping or falling often.
• Loss of feeling in the legs and feet.

As Charcot-Marie-Tooth disease gets worse, symptoms may spread from the feet and legs to the hands and arms. How bad the symptoms are varies greatly from person to person, even among family members.

Other causes of nerve damage, such as diabetes, may cause symptoms like those of Charcot-Marie-Tooth disease. Having another condition with such symptoms can make the symptoms of Charcot-Marie-Tooth disease worse.

Certain medicines, such as the chemotherapy treatments vincristine and paclitaxel, can make symptoms worse. Be sure to tell your healthcare professional about all the medicines you take.

Gene changes that affect the nerves in the feet, legs, hands and arms cause Charcot-Marie-Tooth disease. These gene changes most often pass down through families. But new gene changes can happen when there's no family history of changed genes.

Sometimes, these gene changes damage the nerves. Other changes damage the coating around the nerve, called the myelin sheath. Both changes weaken the messages that travel between the arms and legs and the brain.

Charcot-Marie-Tooth disease is a hereditary disease. That means it passes from parents to children through genes. The risk of getting the condition is higher for people who have parents or brothers or sisters with the condition.

Complications of Charcot-Marie-Tooth disease vary from person to person in how bad they are. Foot issues and trouble walking are often the most serious concerns. And it's possible to harm areas of the body that have less feeling because of Charcot-Marie-Tooth disease.

Sometimes signals from the brain don't make it to the muscles in the feet. Then the muscles don't tighten when they should. This may cause tripping and falling. And the brain may not get pain messages from the feet. So a blister on a toe, for instance, may get infected without your knowing it because you can't feel the pain.

Other complications may include trouble breathing, swallowing or speaking if Charcot-Marie-Tooth disease affects the muscles involved with those activities.

Because Charcot-Marie-Tooth disease is a hereditary disease, there's no way to prevent it. Hereditary means it's passed through families. If you have the condition, genetic testing may help you with family planning.

To diagnose Charcot-Marie-Tooth disease, a healthcare professional takes a medical history and does a physical exam to check for symptoms of the disease.

The following tests may inform your healthcare professional about the cause of the nerve damage and how bad it is:

• Nerve conduction studies. These tests measure the strength and speed of electrical signals sent through the nerves. Electrodes on the skin deliver small electric shocks to the nerve. Delayed or weak responses may mean a nerve condition such as Charcot-Marie-Tooth disease.
• Electromyography. This test also is called EMG. A healthcare professional puts a thin needle electrode through the skin into a muscle. The test measures electrical activity as you relax and as you gently tighten the muscle. This may help show which muscles the condition affects.
• Nerve biopsy. A healthcare professional cuts through the skin at the back of the lower leg and take a small piece of peripheral nerve. The nerve sample goes to a lab, where it's tested to find the cause of the nerve condition.
• Genetic testing. A blood sample goes to a lab to be tested for the most common gene changes known to cause Charcot-Marie-Tooth disease. Genetic testing may help people with the condition do family planning. A gene test also can rule out other causes of nerve damage. A genetic counselor can talk with you about testing.

There's no cure for Charcot-Marie-Tooth disease. But the disease most often worsens slowly. And most often, it doesn't shorten life.

Some treatments can help manage Charcot-Marie-Tooth disease.

Medications

Charcot-Marie-Tooth disease may sometimes cause pain due to muscle cramps or nerve damage. Prescription pain medicine may help manage the pain.

Therapy

• Physical therapy. Physical therapy can help strengthen and stretch the muscles to prevent muscle tightening and loss. A program most often includes low-impact exercises and stretches that a trained physical therapist designs. Physical therapy that's started early and done with regular exercises can help prevent disability.
• Occupational therapy. Weakness in the arms and hands can cause trouble with gripping and finger movements, such as closing buttons or writing. Occupational therapy can help you learn to use assistive devices. These might include special rubber grips on doorknobs or clothes with snaps instead of buttons.

• Orthopedic devices. Many people with Charcot-Marie-Tooth disease need certain orthopedic devices to keep moving and to prevent injury. Leg and ankle braces or splints can help with walking and climbing stairs.

  Boots or high-top shoes can give ankle support. Custom-made shoes or shoe inserts may improve how you walk. Thumb splints can help with gripping and holding things.

Surgery

Surgery to correct issues with the foot may help ease pain and improve walking. Surgery can't improve weakness or loss of feeling.

Potential future treatments

Researchers are studying therapies that may one day treat Charcot-Marie-Tooth disease. These include medicines, supplements, gene therapy and procedures that may help prevent families from passing the disease. These procedures are done outside of the body in a test tube or lab, called in vitro.

Here are some steps you can take to prevent complications of Charcot-Marie-Tooth disease and help you manage its effects:

• Stretch regularly. Stretching can help keep or improve the range of motion of your joints and lower the risk of injury. Stretching also improves your balance and how well you move. If you have Charcot-Marie-Tooth disease, regular stretching can prevent or lessen joint issues that may result from muscles pulling unevenly on bones.
• Exercise daily. Exercise keeps bones and muscles strong. Try low-impact exercises, such as biking and swimming, to put less stress on muscles and joints. Stronger muscles and bones can improve your balance and help you move better, lowering your risk of falls.
• Work on being more stable. Muscle weakness linked to Charcot-Marie-Tooth disease may cause you to be unsteady on your feet. This can cause falls and serious injuries. Walking with a cane, a walker or walking sticks may help. Good lighting at night can help keep you from tripping and falling.

Take care of feet

Because of foot issues and loss of feeling Charcot-Marie-Tooth disease causes, foot care can help ease symptoms and prevent complications:

• Inspect your feet. Check them daily to catch calluses, sores, wounds and infections early.
• Take care of your toenails. Cut your nails often. To keep from getting ingrown toenails and infections, cut straight across. Don't cut into the nailbed. A specialist who treats foot issues, called a podiatrist, can trim toenails for you if you need help. A podiatrist also may be able to suggest a salon where you can have your toenails trimmed safely.
• Wear the right shoes. Choose shoes that fit well and protect your feet. Think about wearing boots or high-top shoes for ankle support. If you have foot issues, such as a hammertoe, you might want to get custom-made shoes.

Support groups bring together people who are coping with the same kinds of challenges. Support groups offer people a place to share common problems. A support group may help you deal with Charcot-Marie-Tooth disease.

Ask your healthcare professional about support groups in your area. The internet, local health department and public library also may be good ways to find a support group in your area.

You may first talk with your main healthcare professional, who may send you to a specialist in conditions of the brain and nervous system, called a neurologist.

Here's some information to help you get ready for your appointment.

What you can do

Ask a family member or friend to go with you to your appointment. This person can help you remember all the information.

Make a list of:

• Your symptoms and when they began.
• All medications, vitamins or supplements you take, including dosages.
• Family members who have symptoms like yours.
• Questions to ask your healthcare professional.

For Charcot-Marie-Tooth disease, some questions to ask include:

• What's the most likely cause of my symptoms?
• What tests do I need?
• What treatments are there? Which do you suggest for me?
• I have other health conditions. How can I best manage these conditions together?
• Do I need to restrict what I do?
• Are there brochures or other printed material that I can have? What websites do you suggest I visit?

What to expect from your doctor

Your healthcare professional may ask you:

• How bad are your symptoms?
• Do you have symptoms all the time, or do they come and go?
• Does anything seem to make your symptoms better?
• Does anything make your symptoms worse?
• Have you or others in your family had genetic testing to confirm the diagnosis?