NINDS Monomelic Amyotrophy Information Page: NINDS


Article title: NINDS Monomelic Amyotrophy Information Page: NINDS
Main condition: Monomelic Amyotrophy
Conditions: Monomelic Amyotrophy
What is Monomelic Amyotrophy?
Monomelic amyotrophy (MMA) is a disease of nerves, known as motor neurons, that are responsible for controlling voluntary muscles. It is characterized by weakness and wasting in a single limb, usually an arm and hand rather than a foot and leg. There is no pain associated with MMA. While some physicians contend that mild sensory loss may be associated with this disease, many experts suggest that such symptoms actually indicate a cause other than MMA. gene exstart profile MMA occurs primarily in males between the ages of 15 and 25. Onset is insidious and progression is slow. MMA is seen most frequently in Asia, particularly in Japan and India; it is much less common in North America. In most cases, the cause is unknown, although there have been a few published reports linking MMA to traumatic or radiation injury. There have also been a few unconfirmed reports of familial occurrence of MMA. Diagnosis is made by physical exam and medical history. Electromyography (EMG), a special recording technique that detects electrical activity in muscles, shows a loss of the nerve supply, or denervation, in the affected limb; MRI and CT scans may show muscle atrophy. People believed to have MMA should be followed by a neuromuscular disease specialist for a number of months to make certain that no signs of other motor neuron diseases develop.

Is there any treatment?
There is no cure for MMA. Treatment consists of muscle strengthening exercises and training in hand coordination.

What is the prognosis?
The symptoms of MMA usually progress slowly for one to two years before reaching a plateau, then remain stable for many years. Disability is generally slight. Occasionally, the weakness progresses to the opposite limb. There is also a slowly progressive variant of MMA known as O'Sullivan-McLeod syndrome, which affects the small muscles of the hand and forearm and has a slowly progressive course.

What research is being done?
The NINDS conducts and supports a broad range of research on motor neuron diseases. The goals of these studies are to increase understanding of these disorders and to find ways to treat, prevent, and ultimately cure them.


This fact sheet is in the public domain. You may copy it.Provided by:
The National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892

Medical Tools & Articles:

Next articles:

Medical Articles:
CureResearch.comTM Copyright © 2010 Health Grades, Inc. All rights reserved.
Home | Contents | Search | Site Map | Feedback | Contact Us | Terms of Use | Privacy Policy | About Us | Advertise