Charcot-Marie-Tooth (CMT) Disease

Overview of Charcot-Marie Tooth Disease

Charcot-Marie-Tooth Disease (CMT) is a genetic condition that affects the nerves in your hands, feet, and legs, making the muscles weak and sometimes causing foot problems like high arches. CMT can make it harder to walk, balance, or do everyday activities. Even though there’s no cure, doctors can help manage it with treatments like physical therapy to make muscles stronger, special braces or shoes for better walking, and sometimes surgery to fix foot issues. These treatments aim to help people with CMT stay active and independent.

Background

Charcot-Marie-Tooth Disease (CMT) is a genetic disorder that affects the nerves that control your muscles, mainly in the hands, feet, legs, and lower arms. It is also called a “hereditary sensory motor neuropathy. This is because CMT is often inherited (hereditary); it can lead to decreased sensation (sensory) and muscle function (motor); and the abnormality affects the nerves (neuropathy). It happens because of mutations (changes) in the genes that help build and protect these nerves, causing them to become increasingly dysfunctional and thereby leading to weakness in the muscles these nerves supply. This leads to symptoms like muscle weakness, loss of sensation, difficulty walking, high foot arches, curled toes (hammer toes), and sometimes problems with balance. CMT usually starts showing symptoms in childhood or early adulthood, but it can appear at any age. Since it’s usually inherited, people are more likely to get it if someone in their family has the condition.

Exam Findings in CMT

Charcot-Marie-Tooth Disease (CMT) is diagnosed by looking at a person’s medical history, doing a physical exam, and using special tests. During the exam, a doctor will check for signs like muscle weakness, reduced reflexes, and problems with balance or foot shape. People with CMT often have very high arched feet and claw toes (Figure 1). This is due to some nerves supplying the muscles affecting the feet being weaker than others.

Special Tests to Diagnose Charcot-Marie-Tooth Disease

To confirm the diagnosis, doctors might do a nerve conduction study, which tests how well the nerves send electrical signals, or an electromyography (EMG), which checks the muscles’ electrical activity. They may also take a blood sample to look for genetic changes that cause CMT. Sometimes, a small piece of nerve tissue is taken (called a nerve biopsy) to be studied under a microscope, but this is less common.

Treatment of CMT

Charcot-Marie-Tooth Disease (CMT) is usually treated by focusing on managing symptoms and keeping muscles and joints as healthy as possible. While there’s no cure, physical therapy can help strengthen muscles and improve flexibility, making it easier to move around. Occupational therapy can teach ways to handle everyday activities if hands and arms are affected. People with CMT might also wear braces or special shoes to support their feet and ankles, helping them walk better. If there are serious foot problems, surgery might be needed to correct them. Pain relief medications can also be used if someone is experiencing discomfort. The goal of these treatments is to help people stay active and maintain their independence.

Edited by Stephen Pinney MD November 11th, 2024