Spinal Muscular Atrophy: Causes, Symptoms And Treatment

Spinal muscular atrophy is referred to a genetic disorder in which a person is unable to control movement of muscles because of loss nerve cells in spinal cord and brainstem. The condition causes muscle wasting and weakness, which might even make it difficult for one to stand, control head movements, walk and in breathe and swallow in some cases. Spinal muscular atrophy is not just one single health condition. It is characterized by a range of diseases – which when grouped together – are known to be the second leading cause of neuromuscular disease. Spinal muscular atrophy can be fatal if it strikes individuals under the age of 3. In December 2016, the first drug – Spinraza – to treat spinal muscular atrophy was approved. Besides this, there is no cure for the condition. People suffering from the condition are treated with the help of assistive devices which help them function in their day-to-day life.
Causes of spinal muscular atrophy
Spinal muscular atrophy occurs when motor neurons in spinal cord and brainstem either stop working because of genetic changes. Motor neurons are referred to the nerve cells which control movement.
The condition is genetic. For a child to have spinal muscular atrophy, both parents are likely to have faulty genes. However, one in 40 adults is carrier of the gene that causes spinal muscular atrophy.
Symptoms of spinal muscular atrophy
Spinal muscular atrophy symptoms are dependent on severity of the condition and the person’s age when it starts. Infants with SMA type I are said to have a weak muscle tone along with facing feeding and breathing problems. In SMA type III, symptoms do not appear until second year of life.
Most symptoms of spinal muscular atrophy are similar to secondary complications of muscle weakness, which can often relived partly by therapy.
Types of spinal muscular atrophy (SMA)
SMA type 1
This is a serious condition. Children affected with SMA type 1 are unable to sit or stand. The condition is said to be fatal before 2 years of age. It can be detected during birth as there may be reduced fetal movement during the final months of pregnancy. At times, the same is visible within the first few months of pregnancy as well.
SMA type II
This condition appears between ages 3 and 15. The infant maybe able to sit, but may never be able to stand or walk. Life expectancy of people suffering from SMA type II is dependent on whether or not the patient experiences bathing problems or not. Most people with SMA type II survive into adulthood.
SMA type III
This kind of SMA appears between the ages 2 to 17. Under this condition, a person has an unusual gait and experiences difficult in running, rising from a chair or climbing steps. There may be a slight tremor of the fingers. Some people with SMA type III also lose the ability to walk and may develop scoliosis. Other complications include osteoporosis and obesity.
Kennedy syndrome
This is a slow progressing inherited condition which appears between 20 to 40 years of age or later. The gene is carried by women and only a son inherits this disorder.
Congenital SMA with arthrogryposis
People with this condition experience persistent contracture of joints. This condition is evident at birth and includes symptoms like curvature of spine, chest deformity, small jaw, respiratory problems and drooping upper eye lids.
Adult SMA or SMA IV
This condition appears after the age of 18. People suffering from SMA IV are able to walk and do not experience any problem with breathing or eating.