Charcot-Marie-Tooth Disease (CMT) is the most common inherited neurological disorder, affecting at least 150,000 individuals in the US. CMT, also known by the descriptive term Hereditary Motor and Sensory Neuropathy (HMSN), is named for the three physicians who first identified the disease in 1886.
CMT is a group of inherited peripheral neuropathies that cause progressive muscle weakness and wasting (atrophy), in the feet, legs, hands, and forearms, as well as diminished sensation in the limbs. Although CMT is characterized by muscle deterioration, the disease is caused by the progressive degeneration of the peripheral nerve cells that carry signals from the spinal chord to the muscles and to the spinal chord from the sensory organs. These nerves tend to deteriorate in a length dependent manner i.e., the longer the nerve the greater the probability of problems, therefore muscle wasting and sensory loss begin in the extremities.
Persons with CMT usually begin to experience symptoms in adolescence or early adulthood, but the onset and symptoms are quite variable even within families. The disease begins with mild indications, typically foot, ankle and hand weakness, but can progress to severe deformities, neuropathic pain, confinement to a wheelchair and the need for assisted breathing.
Some characteristics of CMT:
High arched feet or flat feet, hammer toes, and other foot deformities Frequent foot and ankle sprains Muscle cramping Problems with walking, running and balance Hand weakness, difficulty with writing and other hand functions Pain in the extremities, including neuropathic pain and burning feet
At present, there are no therapies to stop or retard the disease, but there are treatment options, including physical therapy, orthotics (braces, splints and shoe inserts) and surgery. Life expectancy is usually normal, but breathing problems can exist and may be life threatening.