What is it?
Muscular dystrophy (MD) is a group of inherited diseases, in which the muscles that control movement (called voluntary muscles), progressively weaken causing loss of muscle tissue, which worsens over time. Persons with muscular dystrophy may have trouble breathing or swallowing. Their limbs may also draw inward and become fixed in that position, a problem called contracture. Some varieties of the disease can also affect the heart and other organs.
Progressive muscle weakness is the main feature of this disease. Each form varies a bit in terms of the age at which the signs and symptoms usually begin, and the sequence in which different muscle groups are affected.
Duchenne Muscular Dystrophy
About half of all muscular dystrophy cases are the Duchenne variety, which most commonly occurs in boys. Signs and symptoms would initially surface when the child begins to walk and may include:
- Frequent falls
- Difficulty getting up from a lying or sitting position
- Trouble running and jumping
- A waddling gait
- Large calf muscles
- Learning disabilities
Becker Muscular Dystrophy
The signs and symptoms are similar to the Duchenne; although typically milder, it progresses slower. Symptom onset is generally in the teens, but may not occur until the mid-20s or even later.
Other Types of Muscular Dystrophy
Certain types are defined by a specific feature, or the location of the body where symptoms first surface. Examples include:
- Myotonic – Also known as Steinert’s disease, it additionally features an inability to relax muscles at will. It most often starts in early adulthood, and muscles of the face are usually the first to be affected.
- Limb-girdle – The hip and shoulder muscles are usually the first affected. In some cases, it becomes difficult to lift the front part of the foot, so frequent tripping may occur. Signs and symptoms may begin from early childhood to adulthood.
- Congenital – It is apparent at birth, or becomes evident before age 2. Some forms progress slowly and cause only mild disability, while others progress rapidly and cause severe impairment.
- Fascioscapulohumeral (FSHD) – One of the most striking signs of this variety of is that the shoulder blades might stick out like wings when the person raises his or her arms. Onset usually occurs in teens or young adults.
- Oculopharyngeal – The first sign of this is usually drooping of the eyelids. Weakness of the muscles of the eye, face and throat often results in swallowing difficulties. Signs and symptoms first appear in adulthood, usually persons in their 40s or 50s.
As muscle weakness progresses, mobility becomes a problem. Many people will eventually need to use a wheelchair. However, the prolonged immobility of joints associated with wheelchair use can worsen contractures, the drawing inward of the limbs which eventually become fixed in their position.
Contractures may also play a part in the development of scoliosis, a sideways curvature of the spine, which further reduces lung efficiency in people with the disease.
Signs and Tests
The doctor’s exam may show:
- Abnormally curved spine (scoliosis)
- Joint contractures (clubfoot, clawhand, or others)
- Low muscle tone (hypotonia)
A muscle biopsy may be used to confirm the diagnosis. In some cases, a DNA blood test may be all that is needed.
There are no known cures for the various muscular dystrophies. The goal of treatment is to control symptoms.Current treatment is designed to help prevent or reduce deformities in the joints and the spine, to allow those affected to remain mobile as long as possible.
Physical therapy may help patients maintain muscle strength and function. On the other hand, orthopaedic appliances such as braces and wheelchairs, can improve mobility and self-care abilities.
In some instances, surgery on the spine or legs may help improve function/mobility. The person should be as active as possible. Complete inactivity such as bed rest can make the disease worse.
The severity of disability depends on the category of dystrophy. All types slowly get worse, but how fast this happens varies widely. Types such as Duchenne are deadly; persons usually die of respiratory failure before they reach age 40. Yet others cause little disability, and people with them have a normal lifespan.
For family members of affected persons, coping with the illness involves major commitment of physical, emotional and financial resources. The disease presents challenges in the classroom, in the home and in all aspects of life.
In dealing with it, support groups can be a valuable part of a wider network that includes health care professionals, family, friends and community organizations, including places of worship.
Support groups help to bring together people, family and friends who are all coping with the same kind of physical or mental health challenge. They provide a setting in which people can share common problems while supporting each other.