Distal hereditary motor neuropathy type V

Distal hereditary motor neuropathy type V is an inherited disorder of the motor nerves, one of the distal hereditary motor neuropathies, which damage the axons of the motor neurons serving the extremities and cause slowly progressive weakness and wasting of the muscles of the hands and feet. It is sometimes called a spinal form of Charcot-Marie-Tooth disease because the two share symptoms and genetic causes, but it is told apart by the absence of sensory loss. Type V is inherited in an autosomal dominant pattern with incomplete penetrance and is marked by progressive, symmetrical weakness of the upper limbs and wasting of the small muscles of the hands, especially at the base of the thumb. Onset is usually in the teenage years or the twenties, a high arch of the foot is common, life expectancy is normal, and most people keep the ability to walk. Mutations on chromosome 7 have been linked to it, and a rare form involves a splicing mutation in the REEP1 gene. Electromyography shows a pure motor neuropathy. Physical therapy is the main treatment, with orthopedic shoes or foot surgery for foot problems. Its frequency is unknown. This entry records what is documented and is not medical advice.