Muscular dystrophy is a group of disorders characterized by a progressive loss of muscle mass and consequent loss of strength.
The most common form of muscular dystrophy - Duchenne muscular dystrophy - typically affects young boys, but other variations can strike in adulthood.
Currently, there is no cure for muscular dystrophy, but certain physical and medicinal treatments can improve symptoms and slow the disease's progression.
This article will look at the diagnosis, symptoms and treatments for muscular dystrophy, as well as examining current research into future treatments.
Contents of this article:
Fast facts on muscular dystrophy
Here are some key points about muscular dystrophy. More detail and supporting information is in the main article.
- Muscular dystrophy is a collection of muscle-wasting conditions
- Duchenne muscular dystrophy is the most common variant
- A lack of a protein called dystrophin is the main cause of muscular dystrophy
- Roughly 1 in 35,000 males suffer from muscular dystrophy
- Becker muscular dystrophy is similar to Duchenne muscular dystrophy but progress is slower and less severe
- Gene therapies are currently being trialed to combat the disease
- There is currently no cure for muscular dystrophy
- Most types of muscular dystrophies strike at a young age
- Physical and drug therapies can help slow the progression of the disease.
What is muscular dystrophy?
Muscular dystrophy causes the gradual weakening of skeletal muscle.
Muscular dystrophy is a muscle-wasting disease that affects roughly 1 in 35,000 males.
The condition is caused by genetic mutations that interfere with the production of muscle proteins necessary to build and maintain healthy muscles.1
There are a number of muscular dystrophy variants, including the following:
- Duchenne muscular dystrophy: the most common form of the illness. Symptoms normally start before a child's third birthday; they are generally wheelchair-bound by 12 and die of respiratory failure by their early-to-mid-twenties
- Becker muscular dystrophy: similar symptoms to Duchenne but with a later onset and slower progression
- Myotonic (Steinert's disease): the myotonic form is the most common adult-onset form. It is characterized by an inability to relax a muscle once it has contracted. The muscles of the face and neck are often affected first. Symptoms also include cataracts, sleepiness and arrhythmia
- Congenital: this variant can be obvious from birth or before the age of 2. It affects girls and boys. Some forms progress slowly whereas others can move swiftly and cause significant impairment
- Facioscapulohumeral (FSHD): onset can be at almost any age but is most commonly seen during teenage years. The muscular weakness often begins in the face and shoulders. People with FSHD may sleep with their eyes slightly open and have trouble fully closing their eyelids. When an individual with FSHD raises their arms, their shoulder blades protrude like wings
- Limb-girdle: this variant begins in childhood or teenage years and first affects the shoulder and hip muscles. Individuals with the limb-girdle muscular dystrophy might have trouble raising the front part of the foot, making tripping a common problem
- Oculopharyngeal muscular dystrophy: onset is between the ages of 40 and 70. Eyelids, throat and face are first affected, followed by the shoulder and pelvis.2
Muscular dystrophy occurs in both genders and can strike at any age. However, Duchenne muscular dystrophy is the most common form and is most likely to occur in young boys.
The disease is genetic and consequently a history of muscular dystrophy in the family increases the chance of an individual developing the disease.
Symptoms of muscular dystrophy
Below are the symptoms of Duchenne muscular dystrophy, the most common form of the disease. The symptoms for Becker muscular dystrophy are similar but tend start in the mid-twenties or later, are milder and progress more slowly.
- A waddling gait
- Pain and stiffness in the muscles
- Difficulty with running and jumping
- Walking on toes
- Particularly large calf muscles
- Difficulty sitting up or standing
- Learning disabilities, such as developing speech later than usual
- Frequent falls.3
- Inability to walk
- A shortening of muscles and tendons, further limiting movement
- Breathing problems can become so severe that assisted breathing is necessary
- Curvature of the spine can be caused if muscles are not strong enough to support its structure
- The muscles of the heart can be weakened, leading to cardiac problems
- Difficulty swallowing; this can cause aspiration pneumonia and a feeding tube is sometimes necessary.
On the next page, we look at the causes, diagnosis and treatment of muscular dystrophy.