Muscular dystrophies are a group of inherited diseases that damage and weaken your muscles over time. This damage and weakness is due to the lack of a protein called dystrophin, which is necessary for normal muscle function. The absence of this protein can cause problems with walking, swallowing, and muscle coordination.
There are more than 30 different kinds of muscular dystrophies, which vary in symptoms and severity.
Muscular dystrophy can occur at any age, but most diagnoses occur in childhood. Young boys are more likely to have this disease than girls.
The prognosis for muscular dystrophy depends on the type and the severity of symptoms. However, most individuals with muscular dystrophy do lose the ability to walk and eventually require a wheelchair. There’s no known cure for muscular dystrophies, but certain treatments may help.
There are over 30 different types of muscular dystrophy. There are nine different categories used for diagnosis.
Duchenne Muscular Dystrophy
This type of muscular dystrophy is the most common among children. The majority of individuals affected are boys. It’s rare for girls to develop it. The symptoms include:
- trouble walking
- loss of reflexes
- difficulty standing up
- poor posture
- bone thinning
- scoliosis, which is an abnormal curvature of your spine
- mild mental impairment
- breathing difficulties
- swallowing problems
- lung and heart weakness
Individuals with Duchenne muscular dystrophy typically require a wheelchair before their teenage years. The life expectancy for those with this disease is late teens or 20s.
Becker Muscular Dystrophy
Becker muscular dystrophy is similar to Duchenne muscular dystrophy, but it’s less severe. This type of muscular dystrophy also more commonly affects boys. Muscle weakness occurs mostly in your arms and legs, with symptoms appearing between age 11 and 25. Other symptoms of Becker muscular dystrophy include:
- walking on your toes
- frequent falls
- muscle cramps
- trouble getting up from the floor
Many with this disease don’t need a wheelchair until they’re in their mid-30s or older, and a small percentage of people with this disease never require one. Most people with Becker muscular dystrophy live until middle age or later.
Congenital Muscular Dystrophy
Congenital muscular dystrophies are often apparent between birth and age 2. This is when parents begin to notice that their child’s motor functions and muscle control aren’t developing as they should. Symptoms vary and may include:
- muscle weakness
- poor motor control
- inability to sit or stand without support
- foot deformities
- trouble swallowing
- respiratory problems
- vision problems
- speech problems
- intellectual impairment
While symptoms vary from mild to severe, the majority of those with congenital muscular dystrophy are unable to sit or stand without help. The lifespan of someone with this type also varies, depending on the symptoms. Some people with congenital muscular dystrophy die in infancy while others live until adulthood.
Myotonic dystrophy is also called Steinert’s disease or dystrophia myotonica. This form of muscular dystrophy causes myotonia, which is an inability to relax your muscles after they contract. Myotonia is exclusive to this type of muscular dystrophy.
Myotonic dystrophy can affect your:
- facial muscles
- central nervous system
- adrenal glands
- gastrointestinal tract
Symptoms most often appear first in your face and neck. They include:
- drooping muscles in your face, producing a thin, haggard look
- difficulty lifting your neck due to weak neck muscles
- difficulty swallowing
- droopy eyelids, or ptosis
- early baldness in the front area of your scalp
- poor vision, including cataracts
- weight loss
- increased sweating
This dystrophy type may also cause impotence and testicular atrophy in males. In women, it may cause irregular periods and infertility.
Myotonic dystrophy diagnoses are most common in adults in their 20s and 30s. While its symptoms can affect your quality of life, most of the symptoms are not life-threatening. People with myotonic dystrophy often live a long life.
Facioscapulohumeral muscular dystrophy (FSHD) is also known as Landouzy-Dejerine disease. This type of muscular dystrophy affects the muscles in your face, shoulders, and upper arms. FSHD may cause:
- difficulty chewing or swallowing
- slanted shoulders
- a crooked appearance of the mouth
- a wing-like appearance of the shoulder blades
A smaller number of people with FSHD may develop hearing and respiratory problems.
FSHD tends to progress slowly. Symptoms usually appear during your teenage years, but they sometimes don’t appear until your 40s. Most people with this condition live a full lifespan.
Limb-Girdle Muscular Dystrophy
Limb-girdle muscular dystrophy causes weakening of the muscles and a loss of muscle bulk. This type of muscular dystrophy usually begins in your shoulders and hips, but it may also occur in your legs and neck. You may find it hard to get up out of a chair, walk up and down stairs, and carry heavy items if you have limb-girdle muscular dystrophy. You may also stumble and fall more easily.
Limb-girdle muscular dystrophy affects both males and females. Most people with this form of muscular dystrophy are disabled by age 20. However, many have a normal life expectancy.
Oculopharyngeal Muscular Dystrophy (OPMD)
Oculopharyngeal muscular dystrophy causes weakness in your facial, neck, and shoulder muscles. Other symptoms include:
- drooping eyelids
- trouble swallowing
- voice changes
- vision problems
- heart problems
- difficulty walking
OPMD occurs in both men and women. Individuals usually receive diagnoses in their 40s or 50s.
Distal Muscular Dystrophy
Distal muscular dystrophy is also called distal myopathy. It affects the muscles in your:
It may also affect your respiratory system and heart muscles. The symptoms tend to progress slowly and include a loss of fine motor skills and difficulty walking. Most people, both male and female, are diagnosed with distal muscular dystrophy between the ages of 40 and 60.
Emery-Dreifuss Muscular Dystrophy
Emery-Dreifuss muscular dystrophy tends to affect more boys than girls. This type of muscular dystrophy usually begins in childhood. The symptoms include:
- weakness in your upper arm and lower leg muscles
- breathing problems
- heart problems
- shortening of the muscles in your spine, neck, ankles, knees, and elbows
Most individuals with Emery-Dreifuss muscular dystrophy die in mid-adulthood from heart or lung failure.
A number of different tests can help your doctor diagnose a muscular dystrophy. Your doctor can:
- test your blood for the enzymes released by damaged muscles
- test your blood for the genetic markers of muscular dystrophy
- perform an electromyography test on your muscle’s electrical activity using an electrode needle that enters your muscle
- perform a muscle biopsy to test a sample of your muscle for muscular dystrophy
There’s currently no cure for muscular dystrophy, but treatments can help manage your symptoms and slow the progression of the disease. Treatments depend on your symptoms.
Treatment options include:
- corticosteroid drugs, which help strengthen your muscles and slow muscle deterioration
- assisted ventilation
- medication for heart problems
- surgery to help correct the shortening of your muscles
- surgery to repair cataracts
- surgery to treat scoliosis
- surgery to treat cardiac problems
Therapy has proven to be effective. You can strengthen your muscles and maintain your range of motion using physical therapy. Occupational therapy can help you:
- become more independent
- improve your coping skills
- improve your social skills
- gain access to community services