Janice F. Wiesman, MD, FAAN
Janice F. Wiesman, MD, FAAN, clinical associate professor of neurology at New York Grossman School of Medicine in New York City and author of Peripheral Neuropathy: What It Is and What You Can Do to Feel Better.
Bottom Line: CMT: It’s More Common Than You Think
Named for the three doctors who first identified the disorder in 1886—Jean-Martin Charcot, Pierre Marie and Howard Henry Tooth—Charcot-Marie-Tooth disease (CMT) is one of the most common inherited neurological diseases, affecting about one in 2,500 Americans.
People with CMT have one of many genetic mutations that affects the way the peripheral nerves in the arms, hands, feet and legs function. The first signs of CMT are often clumsiness, frequent tripping and/or a feeling of numbness and/or coldness in the hands and/or feet.
Symptoms can appear in childhood, adolescence or middle age and progress slowly, but a patient with CMT may eventually experience muscle wasting in the lower legs and feet, which can hinder walking, and/or muscle atrophy in the hands, which can cause difficulty in performing everyday tasks like writing, preparing food or dressing. Foot deformities, such as a high arch and claw toes, are also a hallmark of CMT.
Anyone who has a family member with CMT or who is experiencing the onset of clumsiness and numbness in the hands or feet, should consult a neurologist experienced in diagnosing and treating CMT. You can find a doctor who has expertise in this field on the website of the Charcot-Marie-Tooth Association, CMTAUSA.org.
CMT is typically diagnosed with a neurological exam, which includes a check of reflexes, skin sensation and gait. Further testing may include a nerve conduction velocity test, which measures the strength and speed of electrical signals in the nerves, or a similar test of the muscles called an electromyogram. Genetic testing is also used, but a negative result cannot rule out CMT, since some types cannot yet be accurately tested. If results of these tests are inconclusive, the doctor may take a nerve biopsy from the leg to check for signs of CMT.
CMT is treated with a regimen of physical therapy that includes strength training and stretching, as well as occupational therapy, which can help patients in performing everyday tasks. Some patients may need leg braces and/or custom footwear. Hearing loss is another possible symptom, so it’s important that patients get their hearing tested and that they wear a hearing aid, if necessary.
There is no cure for CMT, but people with the disease can manage their symptoms with treatment, and they have a normal life expectancy.