Madisons Foundation - Moms And Dads In Search Of Needed Support

What

Facioscapulohumeral Muscular Dystrophy (FSHD) is a disorder that causes weakness in the muscles of the face, scapula (shoulder blades), upper arm, lower leg, and hips. Classic FSHD is a slowly progressive disorder and about 20% of patients will eventually need a wheelchair. Infantile FSHD is a rapidly progressive disorder that usually requires wheelchair use by the age of 9-10 years.

Who

FSHD is the third most common muscular dystrophy and has a prevalence of 1 in 20,000. It appears that more males than females have FSHD, but females have a higher tendency to be asymptomatic, or do not show any of the characteristic muscle weakness. In the classic form of FSHD, the age of onset is between the first and third decade of life, but about 95% will show symptoms before the age of 20 years. As many as one-third of people with classic FSHD will not have any symptoms. The infantile form is more severe with symptom onset during the first few years of life.

Signs and Symptoms

The degree of muscle weakness is highly variable. Children diagnosed with FSHD may have the following symptoms.

• Begins with mild weakness of the facial muscles, such that there is difficulty in closing the eyes tightly, smiling, or whistling. The face may appear smooth and the lips in a pout.
  
• Weakness of the upper arms, specifically the biceps and triceps. The deltoids are spared.
  
• Winged scapula, in which the shoulder blades do not lie flat against the back
  
• Shoulders slope forward • Weakness of the abdominal muscles
  
• Foot drop due to the inability to raise the foot upwards
  
• Hearing loss
  
• Abnormalities in the blood vessels of the retina of the eye, occasionally leading to detachment of the retina and visual problems.
  
• Breathing difficulties (less than 10%) The infantile and classic forms are similar, except that the infantile form begins earlier in life and is more severe.

Possible Causes

The exact cause of FSHD is still largely unknown, although an alteration of genetic material on chromosome 4 is the most likely explanation. In 70-90% of all cases, FSHD is inherited in an autosomal dominant manner, which means that the child receives one copy of the mutated chromosome from one parent and that causes the symptoms of FSHD. 10-30% of the cases are caused by sporadic mutations, which means that neither parent has a mutated chromosome 4. In addition, the disease may appear in children whose parents do not appear to have the disease because of the variability in the symptoms from patient to patient. A child’s parent may have the disease, but be so mildly affected that they have gone undiagnosed.

Diagnosis

Diagnosis of FSHD is based upon evidence of facial weakness and weakness of scapular muscles and/or foot drop. Laboratory tests of blood levels of creatine kinase, an enzyme that is usually elevated when there is muscle damage, may be normal or elevated in children with FSHD. Electromyography, which tests muscle activity, will indicate abnormal activity. Muscle biopsies could also be used to help diagnose FSHD. prenatal diagnosis is available for families with a known history of FSHD. This is done by obtaining fetal cells by chorionic villus sampling or amniocentesis early in pregnancy, and looking for the changes in chromosome 4.

Treatment

There are currently no specific treatments for children with FSHD. Orthotics or braces may be prescribed to help maintain balance during standing and walking. Surgical intervention may also be an option—securing the scapula to the body may improve movement of the arms. It has been thought that albuterol helps increase muscle mass and strength, but may not improve patients’ function much. More research must be done to measure its effectiveness.

Prognosis

Because of the severity of infantile FSHD, most children will require wheelchair use by the age of 9 or 10 years, and about 20% of those with the classic form will eventually need the use of a wheelchair. In most patients, life expectancy is the same as the general population.

Connect with other parents

In the spirit of community and support, Madisons Foundation offers the unique service of connecting parents of children with rare diseases. If you would like to be connected to other parents of children with this disease, please fill out this brief form.

Weblinks

FacioScapuloHumeral Muscular Dystrophy Society:
This website offers mostly educational materials. This organization has its own journal, which is readily accessible through this link.

Muscular Dystrophy Association:
This link is for the section on FSHD. It has educational materials and information on research projects. The link for the home page is http://www.mdausa.org/ . One can search for a local MDA office.

Muscular Dystrophy Family Foundation
This organization helps individuals and families with finding a vendor for adaptive equipment or if needed, financial support for the purchase of adaptive equipment.

Google Search for Facioscapulohumeral Muscular Dystrophy

References and Sources

Darras BT (2004). Limb-girdle, facioscapulohumeral, oculopharyngeal, distal, and congenital muscular dystrophies. UpToDate. Figlewicz DA and Tawil R (2003). Facioscapulohumeral muscular dystrophy. www.geneclinics.org/profiles/fsh/ Fitzsimons RB (1999). Facioscapulohumeral muscular dystrophy. Current Opinion in Neurology. 12:5, p. 501-511. Sripathi N (2001). Facioscapulohumeral muscular dystrophy. www.emedicine.com/neuro/topic133.htm