Spinal muscular atrophy refers to an autosomal recessive motor neuronal disease caused by degenerative changes of the spinal anterior horn cells which eventually lead to the weakening of symmetrical proximal muscles and early death.

The incidence rate is 1 in 6,000~24,000 newborns and 1/40~50 among carriers. This disease can be further classified into Type I, II and III spinal muscular atrophy depending on the age of onset and clinical progress.
The most efficient means of diagnosis of spinal muscular atrophy once included electromyography and muscle biopsy, but ever since the location of the associated gene was identified via genetic analysis in the 1990's with the advances in molecular genetic technologies, diagnosis of the disease through using the distal end of SMN gene (telomeric survivor motor neuron gene; SMNT or SMN1) located on chromosome 5q13 was possible.

Categories of Spinal Muscular Atrophy

There is currently no known cure for spinal muscular atrophy, but prevention and management of complications and rehabilitation are carried out to lessen the degree of severity of the disease. Some of the significant complications include restrictive lung disease, nutrient deficiency and changes in the skeletal system. For restrictive lung disease, it is important to prevent a transition into pneumonia through treatment such as chest percussion, intermittent positive pressure breathing, etc. Scoliosis is one of the most serious complications witnessed among the patients with spinal muscular atrophy.
Wearing a therapeutic corset or having surgery could prove helpful.
Since infants with this disease are unable to be breast or bottle-fed properly, a nutrient deficiency and other related growth problems may occur and thus, adequate precautions must be taken.