Disability associated with MMA is typically mild. In the majority of cases, the disorder usually ceases to progress within five years of onset. People with MMA can expect to have a normal life span.
Monomelic amyotrophy (MMA) is a rare disease of the nerves that control voluntary movements of the limbs.
Monomelic amyotrophy may also be known as benign focal amyotrophy, single limb atrophy, Hirayama syndrome or Sobue disease
Monomelic amyotrophy occurs worldwide and is most prevalent in Asia, and especially in Japan and India. According to a report in 1984, MMA of the lower limb occurs in about four in a million people in India.
Treatment primarily consists of rehabilitation measures such as physical therapy and occupational therapy. Severe muscle weakness (present in a minority of cases) may require orthopedic intervention
Initially, symptoms of MMA can be similar to early signs of other, more serious neurological disorders such as amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease) and spinal muscular atrophy .
The main features of MMA are muscle weakness and atrophy in one limb. The weakness and wasting progresses slowly and may spread to the corresponding limb on the opposite side of the body
Physical findings include reduced muscle girth (width around the arm or leg) and decreased strength in the affected limb. Tendon reflexes tend to be normal or sluggish.
Viral infection, vascular insufficiency of the spinal cord, heavy physical activity, radiation injury, traumatic injury, and atrophy of the spinal cord--have been suggested as possible causes of MMA.
Tests that may aid in diagnosis of MMA include electromyography (EMG), imaging studies such as magnetic resonance imaging (MRI) and computed tomography (CT ) scans, and muscle biopsy .
The main features of the disease are wasting and weakness of a single upper or lower limb. Generally, MMA progresses slowly overa period of 2-4 years, and then reaches a stationary phase
Amyotrophy is another name for muscular atrophy - a reduction in functionality of a muscle due to disease or injury.
The prognosis for most people with Raynaud's disease is very good