Spinal muscular atrophy (SMA) is a rare genetic condition that causes muscles to become weak and emaciated. Most types of SMA are diagnosed in babies or young children.
SMA can cause joint deformities, feeding difficulties, and potentially life threatening breathing problems. Children and adults with SMA may have difficulty sitting, standing, walking, or completing other activities without assistance.
There is currently no known cure for SMA. However, new targeted therapies may help improve the outlook for children and adults with SMA. Supportive therapy is also available to help manage symptoms and potential complications.
Take a moment to learn more about treatment options for SMA.
SMA can affect your child’s body in different ways. To manage their varied support needs, it’s essential to put together a multidisciplinary team of healthcare professionals.
Regular checkups will allow your child’s health team to monitor their condition and assess how well their treatment plan is working.
They may recommend changes to your child’s treatment plan if your child develops new or worsened symptoms. They may also recommend changes if new treatments become available.
To treat the underlying causes of SMA, the Food and Drug Administration (FDA) has recently approved two targeted therapies:
- nusinersen (Spinraza), which is approved to treat SMA in children and adults
- onasemnogene abeparvovec-xioi (Zolgensma), which is approved to treat SMA in children under 2 years old
These treatments are relatively new, so experts don’t yet know what the long-term effects of using these treatments may be. Studies suggest that they may significantly limit or slow the progression of SMA.
Spinraza is a type of medication that’s designed to boost the production of an important protein, known as sensor motor neuron (SMN) protein. People with SMA don’t produce enough of this protein on their own.
If your child’s doctor prescribes Spinraza, they will inject the medication into the fluid surrounding your child’s spinal cord. They will start by giving four doses of the medication over the first couple months of treatment. After that, they will administer one dose every 4 months.
Potential side effects for the medication include:
- increased risk of respiratory infection
- increased risk of bleeding complications
- kidney damage
- back pain
Although side effects are possible, keep in mind that your child’s healthcare provider will only recommend the medication if they believe the benefits outweigh the risk of side effects.
Zolgensma is a type of gene therapy, in which a modified virus is used to deliver a functional SMN1 gene to nerve cells. People with SMA lack this functional gene.
Zolgensma is a one-time treatment that’s administered through intravenous (IV) infusion.
Potential side effects include:
- increased liver enzymes
- serious liver damage
- increased markers of heart muscle damage
If your child’s doctor prescribes Zolgensma, they will need to order tests to monitor your child’s liver health before, during, and after treatment. They can also provide more information about the benefits and risks of the treatment.
Scientists are studying several other potential treatments for SMA, including:
The FDA has not yet approved these experimental treatments. However, it’s possible that the organization might approve one or more of these treatments in the future.
If you’re interested in learning more about experimental options, talk to your child’s doctor about clinical trials. Your healthcare team may be able to give you more information about whether your child could participate in a clinical trial, and the potential benefits and risks.
In addition to targeted therapy to treat SMA, your child’s doctor might recommend other treatments to help manage symptoms or potential complications.
Children with SMA tend to have weak respiratory muscles, which makes it harder to breathe. Many also develop rib deformities, which can worsen breathing difficulties.
If your child has difficulty breathing deeply or coughing, it puts them at increased risk of pneumonia. This is a potentially life threatening lung infection.
To help clear your child’s airways and support their breathing, their health team may prescribe:
- Manual chest physiotherapy. A healthcare provider taps on your child’s chest and uses other techniques to loosen and clear mucus from their airways.
- Oronasal suctioning. A special tube or syringe is inserted into your child’s nose or mouth and used to remove mucus out of their airways.
- Mechanical insufflation/exsufflation. Your child is hooked up to a special machine that simulates a cough to clear mucus from their airways.
- Mechanical ventilation. A breathing mask or tracheostomy tube is used to connect your child to a special machine that helps them breathe.
It’s also important to follow your child’s recommended vaccination schedule to lower their risk of infections, including influenza and pneumonia.
Nutritional and digestive health
SMA can make it hard for children to suck and swallow, which can limit their ability to feed. This can lead to poor growth.
Children and adults with SMA may also experience digestive complications, such as chronic constipation, gastroesophageal reflux, or delayed gastric emptying.
To support your child’s nutritional and digestive health, their healthcare team may recommend:
- changes to their diet
- vitamin or mineral supplements
- enteric feeding, in which a feeding tube is used to deliver fluid and food to their stomach
- medications to treat constipation, gastroesophageal reflux, or other digestive issues
Babies and young children with SMA are at risk of being underweight. On the other hand, older children and adults with SMA are at risk of being overweight or having obesity due to low physical activity levels.
If your child is overweight, their healthcare team may recommend changes to their diet or physical activity habits.
Bone and joint health
Children and adults with SMA have weak muscles. This can limit their movement and put them at risk of joint complications, such as:
- a type of joint deformity known as contractures
- unusual curvature of the spine, known as scoliosis
- distortion of the rib cage
- hip dislocation
- bone fractures
To help support and stretch their muscles and joints, your child’s healthcare team may prescribe:
- physical therapy exercises
- splints, braces, or other orthoses
- other postural support devices
If your child has severe joint deformities or fractures, they may need surgery.
As your child gets older, they may need a wheelchair or other assistive device to help them get around.
Living with a serious health condition can be stressful for children, as well as their parents and other caregivers.
If you or your child is experiencing anxiety, depression, or other mental health challenges, let your doctor know.
They may refer you to a mental health specialist for counseling or other treatment. They may also encourage you to connect with a support group for people living with SMA.
Though there is currently no cure for SMA, there are treatments available to help slow the development of the disease, relieve symptoms, and manage potential complications.
Your child’s recommended treatment plan will depend on their specific symptoms and support needs. To learn more about the treatments that are available, talk to their healthcare team.
Early treatment is important for promoting the best possible outcomes in people with SMA.