What Is Muscular Dystrophy?
Muscular dystrophy is a group of diseases that make muscles weaker and less flexible over time. It is caused by a problem in the genes that control how the body keeps muscles healthy. For some people, the disease starts early in childhood. Others don’t have any symptoms until they are teenagers or middle-aged adults.
How muscular dystrophy affects you or your child depends on the kind. Most people’s condition will get worse over time, and some people may lose the ability to walk, talk, or care for themselves. But that doesn’t happen to everyone. Other people can live for many years with mild symptoms.
There are more than 30 kinds of muscular dystrophy, and each is different based on:
- The genes that cause it
- The muscles it affects
- The age when symptoms first appear
- How quickly the disease gets worse
People usually get one of nine major forms of the disease:
- Duchenne muscular dystrophy (DMD) is the most common form. It mainly affects boys, and starts between ages 3 and 5.
- Becker muscular dystrophy is like Duchenne, except milder. It also affects boys but the symptoms start later -- between ages 11 and 25.
- Myotonic muscular dystrophy is the most common form in adults. People who have it can't relax their muscles after they contract. It can affect both men and women, and it usually starts when people are in their 20s.
- Congenital muscular dystrophy starts at birth or shortly afterwards.
- Limb-Girdle muscular dystrophy often starts in a person's teens or 20s.
- Facioscapulohumeral muscular dystrophy affects the muscles of the face, shoulders, and upper arms. It can affect anyone from teenagers to adults in their 40s.
- Distal muscular dystrophy affects the muscles of the arms, legs, hands, and feet. It usually comes on later in life, between ages 40 and 60.
- Oculopharyngeal muscular dystrophy starts in a person's 40s or 50s. It causes weakness in the muscles of the face, neck, and shoulders, and droopy eyelids (ptosis), followed by difficulty swallowing (dysphagia).
- Emery-Dreifuss muscular dystrophy affects mainly boys, usually starting around age 10. People with this form often have heart problems along with muscle weakness.
There are many treatments that can help keep muscles strong and flexible, and scientists are looking for new ones, too.The important thing is to get the treatment you need and find support.
Muscular dystrophy can run in families, or you can be the first one in your family to have it. The condition is caused by problems in your genes.
Genes contain the information your cells need to make proteins that control all of the different functions in the body. When a gene has a problem, your cells can make the wrong protein, the wrong amount of it, or a damaged protein.
You can get muscular dystrophy even if neither of your parents had the disease. This happens when one of your genes gets a defect on its own. But it’s rare for someone to get it this way.
In people with muscular dystrophy, the broken genes are the ones that make the proteins that keep muscles healthy and strong. For example, those with Duchenne or Becker muscular dystrophies make too little of a protein called dystrophin, which strengthens muscles and protects them from injury.
For most types of muscular dystrophy, symptoms start to show up in childhood or in the teen years. In general, children with the condition:
- Fall down often
- Have weak muscles
- Have muscle cramps
- Have trouble getting up, climbing stairs, running, or jumping
- Walk on their toes or waddle
Some will also have symptoms like:
Getting a Diagnosis
Your doctor will need to check different parts of your child’s body to know if he has muscular dystrophy. He’ll start with a general physical exam. He’ll also ask you questions about your family’s medical history and the kind of symptoms you’re noticing in your child. He may ask:
- Which muscles seem to be giving him trouble?
- Does he have a hard time walking or doing his usual activities?
- How long has this been happening?
- Does anyone in your family have muscular dystrophy? What kind?
He also may ask you questions about how your child plays, moves, and speaks, as well as how he acts at home and at school.
The doctor may use different tests to check for conditions that can cause muscle weakness.
- Blood tests. They check for levels of certain enzymes that muscles release when they are damaged.
- Electromyography, or EMG. Your doctor will put small needles, called electrodes, on different parts of your child’s body and ask him to slowly flex and relax his muscles. The electrodes are attached with wires to a machine that measures electrical activity.
- Muscle biopsy. Using a needle, your doctor removes a small piece of your child’s muscle tissue. He’ll look at it under a microscope to see which proteins might be missing or damaged. This test can show the type of muscular dystrophy your child may have.
- Tests of muscle strength, reflexes, and coordination. These help doctors rule out other problems with his nervous system.
- Electrocardiogram or EKG . It measures electrical signals from the heart and tells how fast your child’s heart is beating and if it has a healthy rhythm.
- Imaging can show the quality and amount of muscle in your child’s body. He may get:
Doctors can also test a sample of his blood to look for the genes that cause muscular dystrophy. Genetic tests can help diagnose the condition, but they’re also important for people with a family history of the disease who are planning to start a family. You can talk with your doctor or a genetics counselor to find out what the results of this test mean for you and your children.
Questions for Your Doctor
You’ll want to find out as much about your child’s condition as you can to learn how he can stay as healthy as possible. You may want to ask:
- What kind of muscular dystrophy does he have?
- Does he need any more tests?
- Do we need to see any other doctors?
- How will the disease affect his life?
- What kinds of treatments are available?
- How will they make him feel?
- What can I do to keep his muscles strong?
- Are there any clinical trials that would be good for him?
- Will my other children get muscular dystrophy?
Right now, there’s no cure for the disease. But there are many treatments that can improve symptoms and make life easier for you and your child.
Your doctor will recommend a treatment based on the type of muscular dystrophy your child has. Some of them are:
- Physical therapy uses different exercises and stretches to keep muscles strong and flexible.
- Occupational therapy teaches your child how to make the most of what his muscles can do. Therapists can also show him how to use wheelchairs, braces, and other devices that can help him with daily life.
- Speech therapy will teach him easier ways to talk if his throat or face muscles are weak.
- Respiratory therapy can help if your child is having trouble breathing. He'll learn ways to make it easier to breathe, or get machines to help.
Medicines can help ease symptoms.
- Eteplirsen (Exondys 51) has been approved to treat DMD. It is an injection medication that helps treat individuals with a specific mutation of the gene that leads to DMD. The most common side effects are balance problems and vomiting. Although the drug increases dystrophin production, which would predict improvement in muscle function, this has not yet been shown.
- Anti-seizure drugs reduce muscle spasms.
- Blood pressure medicines help with heart problems.
- Drugs that turn down the body’s immune system, called immunosuppressants, may slow damage to muscle cells.
- Steroids like prednisone and defkazacort (Emflaza) slow down muscle damage and can help your child breathe better. They can cause serious side effects, such as weak bones and a higher risk of infections.
- Creatine, a chemical normally found in the body, can help supply energy to muscles and improve strength for some people. Ask your child’s doctor if these supplements are a good idea for him.
- Surgery can help with different complications of muscular dystrophy, like heart problems or trouble swallowing.
Scientists also are looking for new ways to treat muscular dystrophy in clinical trials. These trials test new drugs to see if they are safe and if they work. They often are a way for people to try new medicine that isn't available to everyone. Your doctor can tell you if one of these trials might be a good fit for your child.
Taking Care of Your Child
It’s hard when your child loses strength and can’t do the things other kids can do. Muscular dystrophy is a challenge, but it doesn’t have to keep your child from enjoying life.
There are many things you can do to help him feel stronger and get the most out of life.
- Eat right. A healthy, well-balanced diet is good for your child in general. It’s also important for helping him stay at a healthy weight, which can ease breathing problems and other symptoms. If it’s hard for him to chew or swallow, talk to a dietitian about foods that may be easier to eat.
- Stay active. Exercise can improve your child’s muscle strength and make him feel better. Try low-impact activities like swimming.
- Get enough sleep. Ask your doctor or therapist about certain beds or pads that can make your child more comfortable and rested.
- Use the right tools. Wheelchairs, crutches, or electric scooters can help your child if he has trouble walking.
The disease will most likely have a big impact on your family. Remember that it’s OK to ask a doctor, counselor, family, or friends for help with any stress, sadness, or anger you may feel. Support groups are also good places to talk to other people who have lived with muscular dystrophy. They can help your child connect with others like him and give you and your family advice and understanding.
What to Expect
Muscular dystrophy is different for everyone. Some children may lose muscle strength very slowly, giving them and their families time to adjust to the changes. Others will get worse more quickly. Many people with the disease will need wheelchairs and help with daily living at some point, but that’s not always the case.
Talk to your doctor about your child’s muscular dystrophy. Together, you can make the best possible treatment plan for him and get the support you need for your family.
To learn more about muscular dystrophy or find a support group in your area, visit the web site of the Muscular Dystrophy Association.