Hereditary motor sensory neuropathy, type I (Charcot-Marie-Tooth disease), is an autosomal dominant disease characterized by atrophy of the distal muscles of the feet and legs that slowly progresses to involve the muscles of the hands and forearms. The peripheral nerves are clinically enlarged, and deep tendon reflexes are decreased. Motor and sensory nerve conduction velocities are low. Classic Charcot-Marie-Tooth disease is considered to be a relatively benign disease associated with a normal life expectancy. Major functional disability with incapacitation is rare.1,2
See also p 1739.
It is, however, clear that the term encompasses a wide spectrum of clinical disease. Distinct subgroups with significant variation in severity and degree of disability have been described. Since 1927,3 numerous investigators have attempted to classify this complex group of disorders. Several classifications based on inheritance, age at onset, types of neurons affected, pathologic features, and biochemical abnormalities have been proposed, but none