Muscular Dystrophy

What is muscular dystrophy?

Muscular dystrophy is a group of genetic diseases that permanently weaken and shrink your muscles. The disease is rare. However, it gets worse over time. Eventually, the muscle weakness will affect your ability to walk, swallow, and breathe. There are several types of muscular dystrophy:

• Duchenne
• Myotonic
• Limb girdle
• Facioscapulohumeral
• Congenital
• Distal
• Oculopharyngeal
• Emery-Dreifuss

Duchenne is the most common type of muscular dystrophy. Duchenne and Emery-Dreifuss affect males more often than females.

Symptoms of muscular dystrophy

Weakened and shrinking muscles are the underlying cause of the symptoms in each type. The different types of the disease affect different muscle groups. Muscle weakness often begins in one part of your body and progresses to other areas. For example, a person with Duchenne muscular dystrophy may:

• Fall frequently
• Have difficulty getting out of bed or from a chair
• Have difficulty running and jumping
• Walk on their toes or waddle as they walk
• Have overly large calf muscles
• Experience muscle pain, and stiffness

People with Duchenne muscular dystrophy don’t have enough of a protein in their body called dystrophin. Dystrophin helps stabilize muscle cells. Symptoms for most types of muscular dystrophy often begin in childhood. However, some people don’t experience their first symptoms until they become an adult.

Symptoms for each type of muscular dystrophy include:

• Duchenne: This type of muscular dystrophy begins affecting the muscles in your hips, thighs, and pelvis. Then it moves to the muscles in your shoulders, lower arms, and legs. As it progresses, it affects your heart and respiratory muscles.
• Becker: Symptoms usually appear in your teens or young adult life and are similar to the Duchenne type. Muscle weakness progresses much slower and is less predictable.
• Myotonic type 1 and type 2: Symptoms from this type of muscular dystrophy overlap. Both types affect your ability to relax your muscles. Symptoms include general muscle weakness, facial weakness, shrinking muscle mass, cataracts, and heart problems. Children with type 1 myotonic muscular dystrophy have some learning problems. They can have problems planning ahead and making decisions. It can be difficult for them to organize the information they see (called visual-spatial processing).
• Limb-Girdle: Symptoms include muscle weakness in the shoulders, hips, heart, chest muscles, and spine.
• Facioscapulohumeral: Muscle weakness usually begins in the face, shoulders, upper arms, and lower legs before advancing to the eyes, ears, heart, and lower half of the body.
• Congenital (and myopathies): This is a form of type 1 myotonic muscular dystrophy. Symptoms begin with muscle weakness in the neck, arms, trunk, and legs. It can progress to the brain, eyes, throat, heart, chest, nerves, and spine.
• Distal: Symptoms begin with muscle weakness in the lower arms, hands, lower legs, and feet. Eventually, the weakness moves to your nerves and other muscles.
• Oculopharyngeal: Symptoms include drooping eyelids and problems swallowing. Eventually, muscle weakness in your arms and legs causes problems moving (walking, kneeling, bending, climbing stairs).
• Emery-Dreifuss: The classic symptom of this form of muscular dystrophy in young children is toe-walking. This is due to having stiff tendons in your heels. People who have this type of muscular dystrophy have difficulty bending their elbows. Muscle weakness progresses to your arm, neck, and spine. This form tends to advance much slower. Some people experience episodes of fainting due to a weakened heart muscle.

Depending on the type, muscular dystrophy can shorten your lifespan. People who have Duchenne muscular dystrophy, for example, have a life expectancy of under 40 years. But with facioscapulohumeral muscular dystrophy, a more typical lifespan is possible.

How is muscular dystrophy diagnosed?

If you are having muscle weakness problems, see your doctor. Your doctor will ask about your symptoms, medical history, family medical history, and do a physical exam. Your doctor might do an enzyme test. This involves taking a sample of your blood and sending it to a lab. The lab checks for high levels of the creatine kinase (CK) enzyme. CK levels are often elevated in people who have muscular dystrophy. A blood sample also can test your genes for the disease.

Treatment

There is no cure for muscular dystrophy. It is permanent and gets worse over time. Your family doctor will work with specialists to diagnose and best treat it.

Certain things can help your symptoms. These include medicine that improves muscle strength and certain therapies (physical, occupational, and speech). Sometimes these things can prevent complications. Certain medical devices and technology also can help. Those items include equipment (such as a walker or a wheelchair) to help you move and be as independent as possible.

A high-fiber, high-protein diet and drinking plenty of fluids are helpful in reducing the risk of problems affected by not being able to move or exercise. These include obesity, constipation, and dehydration.

Surgery to repair a curved or damaged spine is another possible treatment. If your heart is affected, your doctor may prescribe a heart medicine. If your respiratory (breathing) muscles are seriously weakened, you may need a device to help you breathe. This is called a respirator. You may need to use it part or all of the time.

Living with muscular dystrophy

Living with muscular dystrophy becomes more difficult as muscle weakness progresses. It threatens your health and limits your independence. In the later stages of the disease, you may get more respiratory infections. It’s important to get pneumonia and flu vaccines. Choking may also be a hazard as the muscles in your throat affect your ability to swallow.

Emotionally, losing your ability to move your muscles and be independent can be hard on you and your caregiver. Talk to your doctor about ways to cope or for referrals to a local support group.

Questions to ask your doctor

• If one of my children has muscular dystrophy, is it likely my other children will have it too?
• Does muscular dystrophy contribute to an early death?
• Can a parent be a carrier of muscular dystrophy and not have symptoms?
• Do muscle strengthening exercises help slow the progression of the disease?
• How would I know if someone I am caring for is choking?
• Are there ways to improve the learning disabilities caused by muscular dystrophy?
• If my sibling or in-law has MD, should I get a genetic test to see if I carry that same gene?

Resources

Muscular Dystrophy Association

National Institutes of Health, MedlinePlus: Muscular Dystrophy

National Institute of Neurological Disorders and Stroke