Spinal muscular atrophy (SMA) is the name given to a collection of rare genetic disorders that affect motor neurons. Motor neurons are located in the brain stem and spinal cord and enable the nervous system to communicate with muscles.
In order to remain healthy and function normally, motor neurons depend on a protein called survival motor neuron (SMN) protein. When a person has SMA, levels of this protein are too low, which disrupts communication between the nervous system and muscles. When muscles do not receive signals, muscle tissue weakens, shrinks, and atrophies.
SMA typically affects muscles in the upper back, upper arms, upper legs, and trunk, though it can affect muscles that control things like breathing and swallowing.
There is no cure for spinal muscular atrophy—SMA is a lifelong condition that requires ongoing management. Treatment focuses on managing symptoms, preventing complications, and slowing the progression of muscular atrophy.
Below is a look at how people with SMA and their healthcare providers approach treatment.
Individualized treatment
There are different types of SMA, most of which begin in childhood (though some occur later in life). The specific symptoms, the severity of those symptoms, and the progression of the disorder are different for each person. Accordingly, treatment varies from person to person, taking into account individual symptoms, needs, and goals.
Medications
Physicians have been documenting cases of SMA since the 1890s and identified the genetic mutations that cause SMA in the 1990s. However, the first medication to treat SMA did not become available until 2016. This medication was administered with an injection into the fluid around the spinal cord and works by increasing the production of the SMN protein.
Since the first medication because available, several more medications have become available. These include a gene therapy that is administered to children under the age of 2 who have infantile-onset SMA and an oral medication that also works by increasing SMN protein production.
Additional treatment options are being researched and may become available in the future. You may want to talk to your healthcare providers about the possibility of joining a clinical trial.
Physical therapy and occupational therapy
Physical activity is an important part of SMA. Physical therapy and occupational therapy can help slow the progression of the disorder and improve the quality of life for people with SMA.
Physical therapy or physiotherapy usually focuses on strengthening and stretching exercises designed to help improve muscle function, mobility, and circulation. Occupational therapy may focus on the use of assistive devices (such as braces, splits, or standers), changes around the home, or changes to how a person approaches a certain task, with a goal of making everyday life easier.
People with SMA may work with their healthcare providers to identify and address challenges, such as difficulties with things like speech, breathing, swallowing, and nutrition.
Remember, living with SMA is a different experience for everyone. If you or a loved one is living with SMA, your best sources of information about the condition and treatment options are your healthcare providers.
Medically reviewed in April 2021.
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