Health Topics for Child Health and Development

UI Children's Hospital

UI Family Care Centers

Divisions Within the Department of Pediatrics

Iowa Registry for Congenital and Inherited Disorders

Muscular Dystrophy

Muscular dystrophy is a group of inherited diseases that cause the muscles to weaken and degenerate. The muscles lack a key protein needed for proper muscle function. The voluntary muscle tissue decreases and becomes progressively weak. In late stages, fat tissue replaces lost muscle tissue. This makes the muscles look larger than normal. In most cases, the arms, legs, and spine become deformed. The various types of MD affects more than 50,000 Americans. There is no cure.

Nine forms of muscular dystrophy exist. Duchenne muscular dystrophy is the most common type and the most severe childhood form of the disease. It usually begins before the age of 5 and affects mostly boys. It affects the muscles of the pelvis, upper arms and upper legs. The current life span for persons with the disease is usually shortened to the twenties. Becker's Muscular Dystrophy is a milder form and affects older boys and young men. Progression is over several decades.

Early signs of the disease include:

• a tendency to fall
• lack of coordination
• progressive crippling, resulting in fixations of the joints (contractions)
• difficulty getting up from sitting or lying down
• an unusual, waddling gait
• enlargement of the calf and other muscles or
• a high level of creatine kinase (a muscle enzyme in the blood)

Duchenne's usually appears between ages 2 and 5. Both Duchenne's and Becker's muscular dystrophy are passed from mother to son. The symptoms of muscle weakness may be found in many other serious conditions. It is important to consult with your healthcare provider as soon as possible if these symptoms are identified in your child. Breathing problems and respiratory infections occur as the disease progresses. The course of the disease varies from child to child. A wheelchair is usually needed by age 12.

A physical exam, medical history, and lab tests confirm the diagnosis of muscular dystrophy. The tests include studying a small piece of muscle, a test for muscle and nerve function, and blood tests.

Diagnosis is made by:

• blood tests for enzyme levels of creatine kinase
• electromyography to measure electrical activity of the muscles most affected
• muscle biopsy for disease markers in the muscle tissue and
• genetic testing

Treatment is designed to prevent and/or reduce deformity and may include physical therapy, medications, and assistive devices (braces). Gene therapy seems to be the most promising.

For the family coping with the illness, a significant commitment is involved. Support groups are available.

Last Reviewed 2005

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

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