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July 8, 2017
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July 12, 2017

An Overview of Spinal Muscle Atrophy and Treatment Options

Spinal Muscle Atrophy

Spinal Muscle Atrophy (SMA) is an inherited genetic condition caused by a deterioration of spinal nerve tissue. The disease leads to a loss of size and strength in the muscles surrounding the spinal column, resulting in muscle weakness and paralysis. The disorder is rare, occurring in one out of every 6,000 to 10,000 children.

The main characteristics of SMA are muscle weakness and a decrease in the size of upper arm and leg muscles. The disease is divided into five different categories (0,1,2,3, and 4) based on the level of severity and age of the individual at the time of its discovery. Currently, there is no cure for SMA.

The symptoms of SMA are grouped according to severity and include:

1. SMA 0 (most severe)

  • decreased movement (fetal)
  • swallowing problems
  • joint irregularities
  • respiratory failure

2. SMA 1 (severe)

  • severe muscle weakness before the age of six months
  • inability to sit independently
  • the absence of motor development
  • muscle tone deficiencies
  • Most infants with level I SMA do not live beyond two years old.

3. SMA 2

  • usually, begins between six and twelve months of age
  • cannot walk more than a few steps independently
  • quivering of the fingers
  • can sit independently until the mid-teens

4. SMA 3

  • prone to frequent falls and difficulty navigating stairs between ages two and three
  • the legs are affected to a greater degree than the arms

5. SMA 4

  • muscle weakness usually starts after age 10
  • most individuals can walk until age 60

An abnormal gene inherited from both the mother and the father causes SMA. The diagnosis of the disorder happens when symptoms are noted and is verified by genetic testing. Treatment for SMA depends on the stage of which the individual has been classified. Breathing and nutritional support are often required. In 2017, a new drug, Spiranza, received FDA approval for use in the treatment of children with SMA.

If your child has experienced back problems and you would like to learn about our treatment choices from one of our specialists, please contact our Seguin or New Braunfels offices.

No medical treatment is available

If you have experienced a back injury and would like to learn about our treatment choices from one of our specialists, please contact our Seguin or New Braunfels offices.

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