Duchenne muscular dystrophy (DMD) is a genetic disease. The main sign of DMD is muscle weakness that worsens over time. Before age 5, the muscles in the legs, arms, and trunk begin to weaken. Later in the disease, the heart and respiratory muscles weaken.


DMD is caused by a genetic mutation. The mutation causes the gene to make inadequate amounts of a protein called dystrophin. This protein is needed to keep muscles intact.

Risk Factors

Male children and children with a family history of DMD are at increased risk.


Symptoms of DMD may include:

  • Child is late in learning to walk
  • Larger than normal calf muscles
  • Frequent falls
  • Clumsy walking
  • Difficulty climbing stairs
  • Trouble running
  • Walking on toes or balls of feet
  • Trouble with balance
  • Walking with shoulders back and belly out
  • Trouble keeping up with friends when playing
  • Learning disabilities

Contracture of the Hand

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You will be asked about your child’s symptoms and medical history. A physical exam will be done. You will be asked if there is any family history of neuromuscular disease. The exam will focus on your child’s muscles. Signs of weakness will be looked for. Your child will likely be referred to a specialist.

Your child's bodily fluids and tissues may be tested. This can be done with:

Your child's nerves and muscles may be tested. This can be done with electromyography (EMG).

EMG of the Shoulder

EMG shoulder 2
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Talk with your doctor about the best plan for your child. The disease worsens over time. Your child may need different treatments as the disease progresses. Options include the following:

Therapy plays a large role in treating DMD. Your child will work with a therapist to try to keep muscles strong.

The disease causes contractures. This is when a muscle shortens, making it difficult to move. The therapist will focus on preventing this with range of motion exercises.

Scoliosis is common in DMD. Exercises can help to keep the back as straight as possible.

Braces are used to keep the legs straight and prevent contractures. A walker and wheelchair may be needed later when the leg muscles become too weak to walk.

Steroid medication, like prednisone, may be prescribed. This can help to improve muscle strength and slow muscle weakening. Steroids can weaken bones. To keep bones healthy, vitamin D and calcium supplements may be prescribed. If heart problems exist, medications may be given to slow the damage.

As the disease progresses, the muscles that support breathing may weaken. A ventilator may be needed. It will deliver air through a mask, tube, or sometimes through a surgical hole in the windpipe called a tracheotomy.

Surgery is sometimes used to treat symptoms of DMD. For severe contractures, surgery may be done to release specific tendons. Scoliosis can sometimes interfere with your child’s breathing. In this case, back surgery may be done.


There are no known guidelines to prevent this progressive muscle disease.