Muscle atrophy often produces symptoms such as clumsiness of the hands or weakness of the hands and feet. There are several causes of muscle atrophy:
Muscle diseases
The best-known of these are the muscular dystrophies. Metabolic diseases (e.g. diabetes), some medications or many years of harmful alcohol use can also lead to muscle atrophy.
Diseases of the peripheral nerves
Diseases of peripheral nerves (nerves that travel from the spinal cord to the body) are often not perceived in themselves. When muscle fibers no longer receive normal signals from these nerves, they shrink. In that case muscle atrophy is the only noticeable sign of peripheral nerve disease.
Impingement, pressure on or entrapment of a peripheral nerve (e.g. carpal tunnel syndrome) can cause pain, sensory disturbance and local muscle atrophy, resulting in clumsiness of the hands.
If many peripheral nerves are affected, this is known as polyneuropathy. The commonest causes of this nerve disease are metabolic diseases (diabetes) or years of harmful alcohol use. Rarer forms are caused by vitamin deficiencies or are congenital (genetic). There is often sensory disturbance, especially in the toes and feet, and in more severe cases, sensory disturbance in the hands and weakness in the hands and feet.
The standard examinations used for diseases of the muscles and peripheral nerves are electroneurography (ENG) and electromyography (EMG).
