Spinal muscular atrophy (SMA) is a neuromuscular disorder caused by the absence or deficiency of full-length survival motor neuron protein (SMN). SMN is essential for developing growth or protrusions in the nerves called dendrites and axons. Dendrite and axons transmit impulses to and from neurons (brain cells) and from neurons to muscles. The absence of SMN disrupts this process, and the muscles do not receive signals from the brain.

The muscles stop growing and begin to weaken, and then start shrinking. Children and infants with spinal muscular atrophy are unable to perform motor movements as they grow. They also have problems breathing and swallowing. Some types of SMA can lead to fatalities within a few weeks of birth. There is no cure for SMA yet. However, treatment aims to increase life expectancy and their quality of life through increased SMN production. Treatment begins immediately on a diagnosis. Read on to know the treatment options for spinal muscle atrophy.

1. SMN enhancing treatment

The goal of this treatment is to increase the production of SMN1. Such protocols are known as SMN-enhancing treatments. Nusinersen was the first approved drug to treat both children and adults. The drug is administered into the fluid around the spinal cord. Spiranza, an approved therapy for all SMA affected patients, targets SMN2, a backup gene that can produce small quantities of SMN1 protein. The drug is administered into the spinal cord canal once in four months. FDA approved a gene therapy drug, onasemnogene abeparovec-xioi (Zolgensma ™), for children below two years of age. A safe virus, which delivers a healthy working SMN1 gene, is injected into the motor neurons. The gene then starts producing the SMN protein. It then improves muscle function and life expectancy. As early as August 2020, FDA has approved another oral medication to treat children over two months and older children with SMA.

2. Combination therapies

To improve both life expectancy and increase the production of SMN1, doctors are working on a combination of two or more drugs to increase the effectiveness of the treatment. Trials show promising results, giving hope to many young children with SMA.

3. Physical and occupational therapists

Therapists work with young patients and teach them fine motor skills to become independent. They often work together to improve movement and design exercises to improve motor function in children and adults. They also suggest the right aids and devices that help in mobility and support.

4. Support devices

Most children eventually need wheelchairs or walkers to be mobile. Doctors use breathing devices (a tracheostomy) and feeding (NG or a G-tube) whenever necessary. A few will need it permanently. Doctors recommend a brace or surgery for children with scoliosis (curved spine). They also need periodic physical therapy and occupational therapy to strengthen muscles and joints.