What Is Muscular Dystrophy?

Muscular dystrophy (MD) is a genetic disorder that weakens the muscles that help the body move. People with MD have incorrect or missing information in their genes, which prevents them from making the proteins they need for healthy muscles. Because MD is genetic, people are born with the problem — it's not contagious and you can't catch it from someone who has it.

MD weakens muscles over time, so children, teens, and adults who have the disease can gradually lose the ability to do the things most people take for granted, like walking or sitting up. Someone with MD might start having muscle problems as a baby or their symptoms might start later. Some people even develop MD as adults.

How Do Doctors Diagnose MD?
In addition to doing a physical examination, the doctor will ask you about any concerns and symptoms you have, your past health, your family's health, any medications you're taking, any allergies you may have, and other issues. This is called the medical history.

Tests can help the doctor determine which type of MD a person has and rule out other diseases that affect the muscles or nerves. Some tests measure how nerves and muscles are working. Others check the blood for levels of certain enzymes, the proteins that cause chemical changes like converting food to energy. Abnormally high blood levels of certain enzymes from muscle cells are present in many people with MD.

Sometimes a muscle biopsy is needed. The doctor removes a small piece of muscle tissue and examines it under a microscope. If a person has MD, the muscle tissue will have some unusually large fibers, and some of the other fibers will show signs of breaking down. Finally, genetic testing can show if a person has Duchenne MD.

How Is MD Treated?
There is no cure for MD, but doctors and scientists are working hard to find one. Some scientists are trying to fix the defective genes that lead to MD so they will make the right proteins. Others are trying to make chemicals that will act like these proteins in the body. They hope that this will help the muscles to work properly in people with MD. Doctors are also dedicated to finding the best ways to treat the symptoms of MD so that kids, teens, and adults with the disease can live as comfortably and happily as possible.

Teens with MD can do some things to help their muscles. Certain exercises and physical therapy can help them avoid contractures, a stiffening of the muscles near the joints that can make it harder to move and can lock the joints in painful positions. Often, teens are fitted with special braces to ensure flexible joints and tendons (the strong, rubber band-like tissues that attach muscles to bones). Surgery is sometimes used to reduce pain and increase movement from contractures.

Because we rely on certain muscles to breathe, some teens with MD need respiratory aids, such as a ventilator, to help them breathe. Teens with MD also might need to be treated for problems like scoliosis, which can be caused by weakened muscles or muscles that are contracting or pulling too tightly.

For some types of MD, medication can help. Guys with Duchenne MD may be helped by a medicine called prednisone, and teens with myotonic MD might use phenytoin or quinine to relax muscles.

It's also important that people with heart problems caused by muscular dystrophy be monitored by a heart specialist.