Charcot-Marie-Tooth disease explained

What Charcot-Marie-Tooth disease is

Charcot-Marie-Tooth disease, often shortened to CMT, is a group of inherited conditions that damage the peripheral nerves — the long nerves that carry signals between the spinal cord and the muscles and skin of the limbs. These nerves work rather like electrical wiring, and in CMT either the wires themselves or their insulating covering do not work properly, so signals travel poorly. Because the longest nerves are affected first, the feet and lower legs usually show problems before the hands. CMT is caused by changes in genes and runs in families, though it can vary a lot from person to person, even within the same family. There are several types, differing in the exact gene involved and how the nerve is affected, but they share the same broad pattern of slowly progressive weakness and reduced sensation in the limbs.

The symptoms it causes

Symptoms usually begin in childhood or early adulthood, though they can appear later, and typically progress slowly over many years. Early signs often involve the feet: high arches or, sometimes, flat feet, curled toes, frequent tripping or ankle sprains, and difficulty lifting the front of the foot, which can cause a high-stepping walk or foot drop. Over time the lower legs may become thin as the muscles waste, sometimes described as an inverted champagne bottle shape. The hands can become affected later, with weakness and clumsiness making fiddly tasks like doing up buttons harder. Many people have reduced feeling in the feet and hands, and some have foot pain or cramps. CMT does not usually affect thinking or shorten life expectancy, and its impact ranges widely, from mild and barely noticeable to more disabling.

How it is diagnosed

Diagnosis usually begins with a doctor listening to the symptoms and family history and carrying out a neurological examination, checking muscle strength, reflexes, the shape of the feet and how well sensation is preserved. Because CMT runs in families, a history of similar foot problems or walking difficulties in relatives is an important clue. Special tests called nerve conduction studies measure how well and how fast the nerves carry signals, which can show the pattern typical of CMT and help distinguish its types. Genetic testing can often identify the specific gene involved, which confirms the diagnosis, helps predict how the condition may behave, and informs advice for the wider family. Sometimes other tests are done to rule out other causes of nerve problems. Reaching a clear diagnosis helps guide management and gives access to the right support.

How it is managed

There is currently no cure for CMT, so care focuses on maintaining strength, mobility, comfort and independence, usually through a team approach. Physiotherapy helps keep muscles and joints as strong and supple as possible and advises on exercise, while occupational therapy helps with daily tasks and aids. Many people benefit from podiatry for foot care and from orthotics such as insoles or ankle-foot splints that support the foot and improve walking and stability. Suitable, supportive footwear makes a real difference. Where foot deformities cause significant problems, surgery is occasionally considered. Pain, if present, is managed on an individual basis, and staying active within one's limits helps maintain function. Because CMT can affect balance and sensation, attention to preventing falls and looking after the feet is important, and regular review helps tailor support as needs change over time.

Living well with CMT

Most people with CMT lead full and active lives, and the slow pace of the condition often allows time to adapt. Staying as active as possible, within comfortable limits and with guidance from a physiotherapist, helps maintain strength and mobility, while low-impact activities such as swimming or cycling can be easier on the joints. Good foot care matters, because reduced feeling can mean injuries or pressure sores go unnoticed, so checking the feet regularly and wearing well-fitting shoes is worthwhile. Practical aids, workplace adjustments and support from occupational therapy can keep everyday tasks and work manageable. Because CMT is inherited, some people find it helpful to discuss what it means for their family, and genetic counselling can provide clear, personalised information. Connecting with a patient charity or support group offers practical tips and the reassurance of others who understand the condition.