Facioscapulohumeral muscular dystrophy Health Article

Definition

Facioscapulohumeral muscular dystrophy is progressive muscle weakness and loss of muscle tissue.

See also: Muscular dystrophy

Alternative Names

Landouzy-Dejerine muscular dystrophy

Causes, incidence, and risk factors

Facioscapulohumeral muscular dystrophy affects the upper body, unlike Duchenne muscular dystrophy and Becker muscular dystrophy, which affect the lower body.

Facioscapulohumeral muscular dystrophy is a genetic disorder. It appears in both men and women and may develop in a child if either parent carries the gene for the disorder.

Facioscapulohumeral muscular dystrophy affects approximately 5 out of 100,000 people. It affects men and women equally.

Symptoms

Facioscapulohumeral muscular dystrophy mainly affects the face, shoulder, and upper arm muscles. However, it can affect muscles around the pelvis, hips, and lower leg.

Symptoms often do not appear until age 10 - 26, but it is not uncommon for symptoms to appear much later. In some cases, symptoms never develop.

Symptoms are usually mild and very slowly become worse. Facial muscle weakness is common, and may include:

• Eyelid drooping
• Inability to whistle
• Decreased facial expression
• Depressed or angry facial expression
• Difficulty pronouncing words

Shoulder muscle weakness causes deformities such as pronounced shoulder blades (scapular winging) and sloping shoulders. The person has difficulty raising the arms because of shoulder and arm muscle weakness.

Weakness of the lower legs is possible as the disorder gets worse. The weakness can be severe enough to interfere with walking.

Hearing loss and abnormal heart rhythms may occur, but are rare.

Signs and tests

A physical examination reveals weakness of the facial and shoulder muscles. High blood pressure may be noted but is usually mild. An eye exam may show changes in the blood vessels in the back of the eye.

Tests that may be done include:

• Creatine kinase test (may be slightly high)
• Electrocardiogram (EKG)
• EMG (electromyography)
• Genetic testing of chromosome 4
• Hearing test
• Muscle biopsy (may confirm the diagnosis)

Treatment

There is no known cure for facioscapulohumeral muscular dystrophy. Treatments are given to control symptoms and improve the person's quality of life. Activity is encouraged. Inactivity such as bedrest can make the muscle disease worse. Physical therapy may help maintain muscle strength.

Expectations (prognosis)

Disability is often minor. Lifespan is usually not affected.