FSHD (Facioscapulohumeral Muscular Dystrophy)

What is FSHD?

Facioscapulohumeral muscular dystrophy (FSHD) is a common form of muscular dystrophy (MD). FSHD symptoms typically start in the muscles in your face and upper body but can spread to any muscle in your body. FSHD is an inherited disorder, with symptoms that can start in infancy but typically develop between adolescence and age 20 to 30. There’s no cure, but there are therapies to ease your symptoms and help you keep your quality of life.

Types of facioscapulohumeral muscular dystrophy

The two types of FSHD cause the same symptoms, but happen for different reasons:

• FSHD1, which accounts for 95% of cases, happens when a gene that’s supposed to be inactive in most of your cells becomes active. The reactivated gene makes proteins that destroy muscle cells.
• FSHD2 accounts for the remaining cases. Like FSHD1, protein from a reactivated gene damages muscle. But FSHD2 happens when a different gene mutates, or changes, creating a situation that turns on the inactive genes.

Is FSHD common?

Researchers believe it affects between 4 and 10 in 100,000 people.

What are the symptoms of FSHD?

FSHD (facioscapulohumeral muscular dystrophy) gets its name from Latin and medical terms for the muscles in parts of your body where symptoms typically first appear:

• Facio, the Latin word and medical term for face. People with FSHD can’t “purse” their lips to whistle or sip through a straw. They may sleep with their eyes slightly open because they can’t shut their eyes.
• Scapulo, the Latin word and anatomical term for shoulder blade. FSHD weakens the muscles that hold your shoulder blades in place. When you move your shoulder blades, they stick out and move up toward your neck, so your shoulder blade looks like a wing. Providers may call this scapular winging.
• Humeral, which is the Latin word for the upper arm and the anatomical term for the bone that goes from your shoulder to your elbow. If you have FSHD, your biceps and triceps are unusually weak, making it hard for you to lift your arms higher than your shoulders.

FSHD may affect different muscles at different times. For example, your right arm may be weak, but not your left. Or both arms may be weak, but one will be much weaker than the other. Other common symptoms include:

• Weak lower abdominal muscles, making your belly stick out.
• Sunken breastbone.
• Weak or drooping wrists.
• Chronic fatigue.
• Pain that can be severe.

What are FSHD side effects?

Side effects or complications may include conditions that affect your vision, hearing and your ability to get around. About 20% of people with FSHD need to use wheelchairs after age 50. Specific conditions include:

• Coats disease, when you have abnormal blood vessels in your retina.
• Exposure keratitis, which happens when you can’t close your eye all the way, so your cornea becomes dry.
• High-frequency hearing loss.
• Trendelenburg gait, which happens when the muscle in your thigh that makes it move out is weak so that you sway toward your affected side when you’re walking.
• Footdrop, when you can’t extend or bend your foot upward.
• Lordosis.
• Scoliosis.

What causes facioscapulohumeral muscular dystrophy?

FSHD1 happens when DUX4, a gene in most cells in your body that’s normally inactive becomes active. The reactivated gene produces proteins that damage muscles. Over time, the affected muscles become weak and atrophy (shrink).

FSHD2 happens when the SMCHD1 gene mutates. This gene normally produces proteins that help keep DUX4 genes from being reactivated. When SMCHD1 changes, however, it stops working. As with FSHD1, the reactivated DUX4 genes produce proteins that damage muscle.

How do people inherit FSHD?

People can inherit the condition if either biological parent carries a single copy of an abnormal gene. (This is autosomal dominance). People with FSHD have a 50% chance of passing the abnormal gene on to their children. About 30% of people with FSHD1 don’t have a family history of the condition. Researchers believe that may happen because a new mutation develops after conception, possibly through mosaicism. Mosaicism is when individual cells differ from each other in their genetic makeup.

What are the risk factors for facioscapulohumeral muscular dystrophy?

The most significant risk factor is having a family history of the disease.

How is facioscapulohumeral muscular dystrophy diagnosed?

A healthcare provider will do a physical examination. They’ll ask if you know of anyone in your family with similar symptoms or who has FSHD. Providers may do the following tests:

• Blood tests: Providers check enzyme levels, including serum creatine kinase and serum aldolase. High levels of either enzyme may be a sign of issues with your muscles.
• Neurological tests: Providers do neurological tests to rule out other potential nervous system issues. They may test your reflexes and coordination. They’ll also look for patterns in muscle weakness and to see if your muscles are contracting or tightening (electromyography).
• Muscle biopsy: Providers may do a biopsy to get a sample of muscle tissue that a medical pathologist examines under a microscope.
• Genetic tests: These are the only tests that confirm FSHD and help find out the condition type.

What are treatments for FSHD?

There’s no cure for FSHD, but healthcare providers recommend ways to ease its symptoms:

• Physical therapy.
• Orthotic devices that support weak muscles, like corsets for weak stomach muscles, back supports and braces to support your shoulders and ease shoulder pain.
• Orthotics for your shoes to help you walk and reduce the chance you’ll fall.
• Surgical scapular fixation to improve your shoulder range of motion.

What is the life expectancy for someone with FSHD?

Most people with facioscapulohumeral muscular dystrophy can expect to have normal lifespans.

How do I take care of myself?

Facioscapulohumeral muscular dystrophy is a life-changing disease that healthcare providers can’t cure. Here are some suggestions that may help you navigate life with FSHD:

• Connect with other people with FSHD. This is a rare disorder that many people don’t understand. You may not feel like talking about your situation, and you may feel isolated or lonely. Talking to people going through the same thing you’re experiencing may help.
• Connect with an occupational therapist. FSHD puts limits on what you can do for yourself. It can be frustrating and frightening to lose your independence. Occupational therapy may help you learn how to negotiate your new normal.
• Get some gentle aerobic exercise. Exercise helps with mobility. More than that, exercise helps ease stress. Talk to your healthcare provider before starting an exercise program.

When should I see my healthcare provider?

Talk to your healthcare provider if you notice new muscle weakness or weakness that’s getting worse.

What questions should I ask my healthcare provider?

You may want to ask the following questions:

• No one else in my family has FSHD. Why do I have it?
• What are treatments for the issues I have now?
• Will my symptoms get worse?
• How quickly will my symptoms get worse?
• Should my family have genetic testing?