Bringing hope to a complex condition

The experts at UW Health are national leaders in SMA treatment. We are committed to advancing new therapies for people affected by this life-changing disease.

Your body has more than 600 muscles — each with a critical role to play. Muscles allow you to do everything from walk to breathe. If your muscles become weak, you might find it hard to perform everyday activities. 

Spinal muscular atrophy (SMA) is a genetic condition that causes weakness by damaging the nerves that go to muscles. These nerves are damaged because there is not enough survival motor neuron (SMN) protein to keep them alive. The gene that makes this protein is missing but there is a “copy gene” that makes a small amount of this protein so children can live, though they are still weak. Due to this muscle weakness, individuals with SMA can have difficulty in walking, eating or breathing. Children with SMA have normal brain development and are as smart as other children their age. Children with SMA are able to learn, play, think and interact, building relationships with those around them.

Symptoms and diagnosis

Recognizing SMA

SMA is a genetic condition, caused by a change to a gene called SMN1. This change leads to damage of nerves that control your muscles. These nerves are called motor neurons. When motor neurons break down, they cannot send signals to your muscles to make muscles move. Without these signals, muscles become weak and get smaller.

Symptoms of SMA 

SMA is something you are born with, but symptoms might not develop right away. People can start becoming weak from SMA in infancy, childhood or even during adult years.

The most common presentation can occur in young infants and is the most severe form. Children with this presentation would be described as “floppy” and might miss important developmental milestones such as rolling, sitting or walking when expected. Older infants might be able to roll and sit, but develop weakness that prevents them from standing or walking. Toddlers and young children could start falling more and being unable to walk or run as fast as other children their age.

Because of this range of weakness and symptoms, we used to divide SMA into “types,” with the type 1 SMA being the most severe presentation (an infant who never was able to roll), type 2 SMA describing an infant who could sit at some point but never stand and type 3 SMA patients presenting in early childhood, after being able to stand. We are using this classification less and less, because it does not take into account the effects of early diagnosis and treatment of SMA.

Diagnosing SMA

Diagnosis of SMA is typically made by genetic testing. 

  • If you or a member of your family has a known history of a carrier status or other family member diagnosed with SMA, there are testing options that can be discussed before or during pregnancy with a genetic counselor. 

    • Parents can be tested for carrier status. This will determine the need to test children. 

    • Children can be tested during pregnancy if deemed necessary and safe. This typically includes chorionic villus sampling or amniocentesis. As SMA is a treatable condition, determining the status of your child allows for planning and prompt treatment following birth.

  • Wisconsin is one of 32 states that added SMA testing to be included as part of the newborn screening panel. This means that 24 hours after birth, whether in a medical institution or other arrangement, a heel prick is completed and tested for this condition through the state testing lab.

Genetic testing also can be arranged for any person if SMA is suspected. 

Treatments and research

SMA treatments

Our UW Health Kids specialists can provide the most current treatment options that best suit your child's and your family’s needs. We are happy to discuss all options, experiences and expectations to aid in this determination.

Treatment options

Zolgensma is an FDA-approved, gene replacement therapy for the treatment of patients with SMA under 2 years of age.  Zolgensma works by replacing the missing or mutated SMN1 gene with a one-time intravenous (IV) infusion, which provides the cells with the new DNA to produce the missing protein and prevent muscle loss or weakness. 

At UW Health, we had the opportunity to be involved early in learning about the results, effects and outcomes associated with this treatment, while we were involved in the early clinical trials and were the first site in Wisconsin to use gene therapy for treatment of SMA.

Spinraza is an FDA-approved treatment for all ages and types of SMA. Spinraza works by increasing the amount of functional protein generated by the SMN2 gene, nourishing the nerves responsible for muscle function and movement. Spinraza is given by an intrathecal injection, meaning directly into the cerebrospinal fluid, with a puncture into the lower back. It requires four loading doses within the first two months and treatment every four months after that indefinitely. 

Our UW Health Kids specialists understand the distress that medical procedures can inflict on not only a child, but the entire family. We have a multidisciplinary team to aid with comfort in dosing to include anesthesia, child life specialists, respiratory therapy, radiology, pre/post-operative staff and our neurology providers, who specialize in children with neuromuscular disease. We have had success in dosing patients with even the most complex spines and medical issues.

Evrysdi is the newest FDA-approved treatment for SMA, which includes all ages and types of those with SMA over 2 months of age. Evrysdi works by increasing the amount of functional protein generated by the SMN2 gene, nourishing the nerves responsible for muscle function and movement. Evrysdi is given via oral/feeding tube once daily for the duration of the individual's lifetime.

In Spring 2020, we were fortunate to be able to enroll as an expanded access program for this treatment, providing it to our patients prior to its final approval by the FDA.

The timing of treatment with any of these options is critical, as those dosed as soon as able had better outcomes than those who waited. Our UW Health Kids specialists work to provide treatment in a timely manner, with a clear understanding of the implications delays can cause on your child’s outcomes.

Supportive therapies

In addition to the treatments listed above, supportive therapies remain pertinent and a mainstay in the ongoing care for patients affected by SMA. These additional resources will be provided to you as needed with your care and can include:

Ventilatory support, airway clearance

Calculations of nutritional needs, specialized diets, feeding tube management/discussions

Rehabilitation physician, physical therapy, occupational therapy, vocational counseling, communication aids and systems (CASC), orthotics (splinting/bracing), equipment needs.

Scoliosis management

Resource support/financial support with our social work team

Clinical research

Clinical research is vital to our understanding of SMA. Clinical trials give you access to new treatment options. Many gene therapy treatments for SMA are being tested through clinical trials. Learn more about SMA research at the University of Wisconsin School of Medicine and Public Health and UW Health

Meet our team

An expert, compassionate team

Our pediatric neurologists are committed to advancing the treatment of SMA through expert, compassionate care and research. We have exceptional experience in treating this condition with a large following at our facility and within our Pediatric Neuromuscular Clinic.

Our UW Health Kids SMA specialists see pediatric patients 18-21 years of age at our Pediatric Neurology Clinic at UW Health and at the American Family Children’s Hospital in Madison, Wis., after which time they can be transferred to the Adult Neuromuscular specialists at UW Health in Madison.


Care for your child

American Family Children’s Hospital

At American Family Children’s Hospital, you will find a friendly, child-centered environment. Our hospital is designed with relaxing spaces and areas where children are encouraged to play. 

Patient stories

Stopping a devastating condition

Piper was just a week old when her parents learned she had SMA. Without treatment, her muscles would weaken. Breathing and eating would become difficult. At three weeks old, Piper was the first child in Wisconsin treated with a new gene therapy for spinal muscular atrophy. Read Piper’s story

Patient and support services

Resources for you

An SMA diagnosis can be hard for families to cope with. There are many national SMA resources you can turn to for information and support:

Online resources

Smiling child with sign reading UW Health Kids
UW Health Kids
Our pediatric experts have served the special needs of children for more than 100 years. We focus on each child’s unique needs and offer social and emotional support to help you and your child face even the most complex condition. Our long history includes the creation of medical advances that save lives around the world. Together, we get your child back to health and enjoying being a kid.