Scoliosis in Children with Muscular Dystrophy

Scoliosis in Children with Muscular Dystrophy

Muscular dystrophy (MD) is a genetic disorder that results in progressive muscle wasting. Nine forms of MD exist, each affecting different sets of muscles. Some children who are diagnosed with MD may develop an abnormal curve in the spine known as scoliosis. This can lead to pain, decreased function, and respiratory problems.

Undergoing treatment for MD-related scoliosis can help slow, or even stop, the spinal deformity from progressing. As a result, the child will become more comfortable and enjoy a better quality of life. In addition, treatment may improve the child’s ability to perform the activities of daily living more independently.

How does muscular dystrophy affect the spine? What are some ways in which doctors can slow the progression of this degenerative disease? And, when is surgery necessary? Use this guide to understand more.

Understanding Muscular Dystrophy

Muscular dystrophy is often the result of a mutation in someone’s genes. In fact, some families display a history of the disorder. Other children may develop it without any prior family history.

MD affects the gene responsible for making proteins—mainly dystrophin—that allow the body to build and maintain healthy muscles. Specifically, the loss of dystrophin affects skeletal muscle cells. As a result, certain muscles become weak and start to waste away. This leads to problems with ambulation and meeting certain developmental milestones. Some forms of MD can also affect the heart, lungs, and pulmonary function.

In addition, the degeneration of the muscles can lead to scoliosis. This abnormal sideways curve of the spine can be painful and severely limit a child’s abilities.

The two forms of MD that typically lead to scoliosis include:

  • Duchenne Muscular Dystrophy (DMD): The most common form of MD, affecting 1 in every 3,600-6,000 newborn males. Virtually no functional dystrophin is made by the body. Symptoms usually start between the ages of 1 and 5 and start progressing rapidly. Early indicators include delayed motor skills like sitting, standing, or walking. Eventually, the child will lose the ability to walk—usually requiring wheelchair use by adolescence. In addition, the lack of dystrophin weakens the heart muscles, leading to a condition known as cardiomyopathy.
  • Becker Muscular Dystrophy (BMD): A less common form of MD. In fact, BMD only affects about 1 in every 30,000 boys. The symptoms are similar to DMD but start out later in adolescence—usually during the teen years. Symptoms typically progress much slower than with DMD. With BMD, the body still makes some partially functional dystrophin. Muscle weakness generally starts in the hips, pelvic area, and thighs. Some children with BMD may also have enlarged calves due to fatty deposits replacing muscles. Prognosis is generally better for those with BMD, although it depends on how badly the heart is compromised.

How Muscular Dystrophy Leads to Scoliosis

As is the case of children with DMD, muscular weakness begins to affect their ambulation and ability to change positions. They usually exhibit one of the tell-tale characteristics of DMD—Gower’s sign. This sign manifests when a child rises from a sitting or lying position by walking his hands up the legs. In particular, this motion helps to compensate for the weakness in the gluteus maximus and quadriceps muscles.

A child with DMD usually loses the ability to walk between the ages of 6 to 12. At first, the child can maintain posture and get around with wheelchair use. This lack of mobility, combined with increasing muscle weakness, eventually leads to changes in the trunk. As the trunk grows weaker, neuromuscular scoliosis may develop.

Understanding Scoliosis

The spine isn’t a straight line that extends from the base of the neck to the pelvis. It actually contains natural curves that distribute weight and stress as the body moves or rests. These natural curves turn forward and backward in the body. If you were looking at an image of the spine from the side of a person, it would actually resemble an “S” shape.

Some curves aren’t natural. Curves that twist to the left or right are not normal. This is a condition known as scoliosis. Calling it a curve, however, may be oversimplifying. It is actually a complex condition that involves the rotation of the spine. As a result, areas between the vertebrae become compressed or overstretched, causing painful and chronic conditions.

Scoliosis has several causes. For those affected by muscular dystrophy, it is generally due to wheelchair use and progressive muscle deterioration. As the trunk muscles lose their ability to support the body, the spine begins to change. For those with DMD, this can happen rather quickly. In fact, boys with DMD can experience an increase in scoliosis angulation between 16 and 24 degrees per year.

In addition, the shape of the spine for those with DMD is different than for those with other forms of scoliosis. Those with another common form of the condition—idiopathic scoliosis—usually experience the curve higher in the body, typically near the middle of the chest. The apex of the curve for those with MD usually occurs where the chest and lower back meet. As a result, the area can also have an abnormal outward curve (kyphosis).

Treating Scoliosis in Children with Muscular Dystrophy

When a child is diagnosed with MD, especially DMD, taking measures to prevent scoliosis is very important. Once a child with DMD develops scoliosis, surgical correction is the only solution.

By using a multidisciplinary approach, children with MD can stay independent for longer. The more that a child can move around, the more strength that he can maintain. This affects the severity of scoliosis in the long term.

A typical multidisciplinary approach includes input from physiotherapists, physical therapists, pediatric spine specialists, respiratory therapists, and cardiologists. Each discipline offers different benefits for the child with MD. For example, physical therapy can help maintain a child’s muscle tone and reduce the severity of joint contractures.

Steroid injections offer several benefits for children with DMD. This includes increased muscle strength, independent ambulation, and the decreased progression of scoliosis. If a child can maintain ambulation until his pubertal growth spurt, it may reduce the risk of developing scoliosis. A steroid injection can also aid with breathing and heart function.

Steroid therapy has some risks, however. Decreased bone density, spinal compression, and long bone fractures are a concern. Also, some boys will develop cataracts from steroid use. Vitamin supplements, proper nutrition, and adjuvant therapies can help decrease these risks.

In addition, developments in orthotics and wheelchair technology can increase a child’s comfort and slow deformities of the spine. Scoliosis bracing may also be an option before the spinal deformity becomes too defined.

Treating Scoliosis with Surgery

As you probably know, MD has no cure. Surgery, however, can relieve painful symptoms, stabilize the spine, and resolve some respiratory problems. Candidates for surgery include those with a quick progression of scoliosis and those who are suffering from heart and breathing problems. Surgery is often recommended for developing boys with a scoliotic curve beyond 20 degrees.

Spinal fusion surgery can correct the spine and stop the progression of scoliosis. Usually, this surgery uses a bone graft and surgical hardware like pedicle screws to stabilize the spine and help vertebrae grow together. In time, this fusion limits any extra movements of the spine, despite weakening trunk muscles.

In general, those with MD who undergo surgery for their scoliosis experience favorable results. This includes better sitting balance and improved function. Less pain and decreased deformity also improve the child’s quality of life. Experts still disagree about the effectiveness of scoliosis surgery on respiratory function. Therapies like steroids, non-invasive ventilation, and respiratory therapy, however, can be combined effectively with surgery to increase respiratory function and prolong life expectancy.

How Dr. Lowenstein Can Help

Scoliosis is a complicated spine condition even for those without muscular dystrophy. This degenerative disease only makes spinal issues more complex. Seeing a doctor who specializes in scoliosis and spinal deformity surgery is crucial. These doctors specialize in stabilizing the spine and allowing the child to live as comfortably and independently as possible.

With almost two decades of experience, Dr. Jason Lowenstein has the skills and knowledge to handle the complexities of muscular dystrophy and scoliosis. Let Dr. Lowenstein and his team guide you through the process of determining the best treatments. Schedule an appointment today and find out firsthand why Dr. Lowensteins is consistently rated one of the area’s Top Doctors.