Overview

Muscular dystrophy is a group of diseases that cause progressive weakness and loss of muscle mass. In muscular dystrophy, abnormal genes (mutations) interfere with the production of proteins needed to form healthy muscle.

There are many different kinds of muscular dystrophy. Symptoms of the most common variety begin in childhood, mostly in boys. Other types don't surface until adulthood.

There's no cure for muscular dystrophy. But medications and therapy can help manage symptoms and slow the course of the disease.

Source: http://www.mayoclinic.com

Symptoms

The main sign of muscular dystrophy is progressive muscle weakness. Specific signs and symptoms begin at different ages and in different muscle groups, depending on the type of muscular dystrophy.

Duchenne type muscular dystrophy

This is the most common form of muscular dystrophy. Although girls can be carriers and mildly affected, it's much more common in boys.

About one-third of boys with Duchenne muscular dystrophy (DMD) don't have a family history of the disease, possibly because the gene involved may be subject to sudden abnormal change (spontaneous mutation).

Signs and symptoms typically appear in early childhood and may include:

• Frequent falls
• Difficulty rising from a lying or sitting up position
• Trouble running and jumping
• Waddling gait
• Walking on the toes
• Large calf muscles
• Muscle pain and stiffness
• Learning disabilities

Becker muscular dystrophy

Signs and symptoms are similar to those of Duchenne muscular dystrophy, but tend to be milder and progress more slowly. Symptoms generally begin in the teens but may not occur until the mid-20s or even later.

Other types of muscular dystrophy

Some types of muscular dystrophy are defined by a specific feature or by where in the body symptoms first begin. Examples include:

• Myotonic. Also known as Steinert's disease, this form is characterized by an inability to relax muscles at will following contractions. Myotonic muscular dystrophy is the most common form of adult-onset muscular dystrophy. Facial and neck muscles are usually the first to be affected.
• Facioscapulohumeral (FSHD). Muscle weakness typically begins in the face and shoulders. The shoulder blades might stick out like wings when a person with FSHD raises his or her arms. Onset usually occurs in the teenage years but may begin in childhood or as late as age 40.
• Congenital. This type affects boys and girls and is apparent at birth or before age 2. Some forms progress slowly and cause only mild disability, while others progress rapidly and cause severe impairment.
• Limb-girdle. Hip and shoulder muscles are usually the first affected. People with this type of muscular dystrophy may have difficulty lifting the front part of the foot and as a result may trip frequently. Onset usually begins in childhood or the teenage years.

When to see a doctor

Seek medical advice if you notice signs of muscle weakness — such as increased clumsiness and falling — in yourself or your child.

Source: http://www.mayoclinic.com

Causes

Certain genes are involved in making proteins that protect muscle fibers from damage. Muscular dystrophy occurs when one of these genes is defective.

Each form of muscular dystrophy is caused by a genetic mutation particular to that type of the disease. Many of these mutations are inherited. But some occur spontaneously in the mother's egg or the developing embryo and can be passed on to the next generation.

Source: http://www.mayoclinic.com

Diagnosis

Your doctor is likely to start with a medical history and physical examination.

After that, your doctor may recommend:

• Enzyme tests. Damaged muscles release enzymes, such as creatine kinase (CK), into your blood. In a person who hasn't had a traumatic injury, high blood levels of CK suggest a muscle disease — such as muscular dystrophy.
• Electromyography. An electrode needle is inserted into the muscle to be tested. Electrical activity is measured as you relax and as you gently tighten the muscle. Changes in the pattern of electrical activity can confirm a muscle disease.
• Genetic testing. Blood samples can be examined for mutations in some of the genes that cause different types of muscular dystrophy.
• Muscle biopsy. A small piece of muscle can be removed through an incision or with a hollow needle. Analysis (biopsy) of the tissue sample can distinguish muscular dystrophies from other muscle diseases.
• Heart-monitoring tests (electrocardiography and echocardiogram). These tests are used to check heart function, especially in people diagnosed with myotonic muscular dystrophy.
• Lung-monitoring tests. These tests are used to check lung function.

Source: http://www.mayoclinic.com

Complications

The complications of progressive muscle weakness include:

• Trouble walking. Some people with muscular dystrophy eventually need to use a wheelchair.
• Shortening of muscles or tendons around joints (contractures). Contractures can further limit mobility.
• Breathing problems. Progressive weakness can affect the muscles associated with breathing. People with muscular dystrophy may eventually need to use a breathing assistance device (ventilator), initially at night but possibly also during the day.
• Curved spine (scoliosis). Weakened muscles may be unable to hold the spine straight.
• Heart problems. Muscular dystrophy can reduce the efficiency of the heart muscle.
• Swallowing problems. If the muscles involved with swallowing are affected, nutritional problems and aspiration pneumonia may develop. Feeding tubes may be an option.

Lifestyle and home remedies

Dietary changes haven't been shown to slow the progression of muscular dystrophy. But proper nutrition is essential because limited mobility can contribute to obesity, dehydration and constipation. A high-fiber, high-protein, low-calorie diet may help.

Source: http://www.mayoclinic.com

Coping and support

A diagnosis of muscular dystrophy can be extremely challenging. To help you cope:

• Find someone to talk with. You may feel comfortable discussing your feelings with a friend or family member, or you might prefer meeting with a formal support group.
• Learn to discuss your child's condition. If your child has muscular dystrophy, ask your doctor about the most appropriate ways to discuss this progressive condition with your child.

Source: http://www.mayoclinic.com

Risk factors

Muscular dystrophy occurs in both sexes and in all ages and races. However, the most common variety, Duchenne, usually occurs in young boys. People with a family history of muscular dystrophy are at higher risk of developing the disease or passing it on to their children.

Source: http://www.mayoclinic.com