Learn about CMT

Charcot-Marie-Tooth disease (CMT) is not one disease but a family of inherited peripheral neuropathies. It is named after the three physicians who first described it in 1886. It is one of the most common inherited neurological conditions worldwide.

In CMT, the peripheral nerves that connect the brain and spinal cord to the muscles and to sensory receptors gradually stop working as well as they should. Depending on the subtype, the problem may be with the insulating myelin sheath (demyelinating types) or with the nerve fibre itself (axonal types).

Because the longest nerves are affected first, symptoms usually begin in the feet and lower legs, and later involve the hands. Common features include high arches or flat feet, hammer toes, foot drop, reduced ankle reflexes, muscle wasting in the calves and hands, numbness, and difficulty with fine tasks such as buttons or keys.

CMT is usually slowly progressive over years or decades. It is not contagious, it does not shorten life expectancy for most people, and it varies widely — even within the same family one person may be severely affected while another has barely any symptoms.

Diagnosis is made by a clinician, usually with a neurological examination, nerve conduction studies or EMG, family history, and often genetic testing to identify the specific subtype.