Throughout life, we are likely to face a number of serious and not-so-serious events that can interfere with our plans or even compromise our future, and one of them is muscular dystrophy.

What is Muscular Dystrophy?

Muscular dystrophy is a group of disorders that cause progressive loss of muscle mass and, as a result, loss of muscle strength. It is a condition caused by genetic mutations that interfere with the production of the muscle proteins needed to build and maintain healthy muscles. The absence of these proteins can cause problems with muscle coordination, as well as with walking and swallowing. It is a genetic disease and, consequently, a family history of muscular dystrophy increases the chances of another family member developing the disease. Muscular dystrophy can occur at any stage of life, but it is usually diagnosed in childhood. Boys are more likely to develop this disorder than girls. The diagnosis of muscular dystrophy depends on the type and severity of symptoms. However, most people with muscular dystrophy lose the ability to walk and therefore need to use a wheelchair.

Types of Muscular Dystrophy

There are more than 30 different types of muscular dystrophies, but only some have their symptoms and severity widely known:

Duchenne Muscular Dystrophy

It is the most common type of the disease. And it is the most frequent form in children. Symptoms usually begin before the age of three. The vast majority of those affected are male; it is uncommon for girls to develop Duchenne muscular dystrophy. People with Duchenne muscular dystrophy generally need a wheelchair before the age of 12. Life expectancy for people with this disease is the end of adolescence or the beginning of the second decade of life. Symptoms:

  • Loss of reflexes
  • Difficulty walking
  • Difficulty getting up when seated
  • Bone weakening
  • Poor posture
  • Scoliosis (which is excessive curvature of the spine)
  • Breathing difficulties
  • Difficulty swallowing
  • Weakening of the lungs and heart
  • Mild intellectual disability

Becker Muscular Dystrophy

Becker muscular dystrophy is very similar to Duchenne muscular dystrophy, but less severe. This type of muscular dystrophy also affects a greater number of males. Symptoms appear between the ages of 11 and 25 and begin with muscle weakness primarily in the arms and legs. Many people with this disease will only need a wheelchair around the age of thirty or a little later, while a small percentage never need one. Most of these people live into middle age or beyond. Symptoms:

  • Walking on tiptoes
  • Frequent falls
  • Muscle cramps
  • Difficulty getting up from the floor

Congenital Muscular Dystrophy

Congenital muscular dystrophies are often discovered between birth and 2 years of age, which is when the child starts to show difficulties in the development of motor functions and muscle control. Parents, noticing such limitations, seek medical help. Although symptoms range from mild to severe, most people with congenital muscular dystrophy need help to sit or stand, as they can’t do it alone. Life expectancy for someone with this type of disease varies, depending on the symptoms. Some of them die in childhood, while others live into adulthood. Symptoms:

  • Muscle weakness
  • Breathing problems
  • Poor motor control
  • Difficulty swallowing
  • Being unable to sit or stand without support
  • Scoliosis
  • Foot deformities
  • Intellectual disability
  • Vision problems
  • Speech problems

Emery-Dreifuss Muscular Dystrophy

Emery-Dreifuss muscular dystrophy is another type that tends to affect boys more than girls. In general, it starts to appear in childhood. Most people with Emery-Dreifuss muscular dystrophy die in middle adulthood, from respiratory or heart failure. Symptoms:

  • Weakness in the muscles of the arms and legs
  • Heart problems
  • Breathing problems
  • Shortening of the muscles of the spine, neck, elbows, knees, and ankles

Myotonic Dystrophy

This form of muscular dystrophy, also called Steinert disease or Myotonic dystrophy, causes the muscles to become unable to relax after contracting (myotonia). Myotonia only happens in this type of muscular dystrophy. Myotonic dystrophy can affect the muscles of the face, as well as the adrenal glands, central nervous system, thyroid, eyes, heart, and gastrointestinal tract. This type of dystrophy can also cause impotence and testicular atrophy in men; in women, it can cause irregular menstrual periods and infertility. Myotonic dystrophy is usually diagnosed in adults between twenty and thirty years old. Although the symptoms can affect quality of life, most are not life-threatening and often patients have a long life. Symptoms usually first appear on the face and neck. Drooping facial muscles can give a thin and haggard appearance. Symptoms:

  • Difficulty lifting the neck (weak neck muscles)
  • Difficulty swallowing
  • Weight loss
  • Drooping eyelids (ptosis)
  • Vision problems, including cataracts
  • Early baldness in the front of the head
  • Increased sweating

Oculopharyngeal Muscular Dystrophy

Oculopharyngeal muscular dystrophy occurs in both men and women and is generally diagnosed when a person is around forty to fifty years old. It causes weakness in the muscles of the face, neck, and shoulders. Symptoms:

  • Voice changes
  • Drooping eyelids (ptosis)
  • Vision problems
  • Difficulty swallowing
  • Difficulty walking
  • Heart problems

Facioscapulohumeral Muscular Dystrophy

Facioscapulohumeral muscular dystrophy is also known as Landouzy-Dejerine disease. This type of muscular dystrophy tends to affect the muscles of the face, shoulders, and arms. Facioscapulohumeral muscular dystrophy progresses slowly; and symptoms usually appear during adolescence, but can remain hidden until around forty years old. People with this type of dystrophy have difficulty chewing or swallowing and their mouth may appear crooked. Shoulders slope and shoulder blades resemble wings. A smaller number of people may develop hearing and breathing problems. Most people who develop this disease have a normal life expectancy.

Limb-Girdle Muscular Dystrophy

Limb-girdle muscular dystrophy causes muscle weakness and muscle loss. This form of muscular dystrophy affects both sexes. Limb-girdle muscular dystrophy usually starts in the shoulders and hips, but can also occur in the legs and neck. People with this type of muscular dystrophy may find it hard to get up from a chair, go up and down stairs, move sideways, and carry heavy objects. They may also trip and fall more easily. Most people with this form of muscular dystrophy become disabled by around 20 years old; however, most have a normal life expectancy.

Distal Muscular Dystrophy

This type, also called Distal Myopathy, affects the muscles of the arms, hands, legs, and feet. It can also affect the respiratory and heart muscles. Symptoms, which include loss of fine motor skills and difficulty walking, tend to progress slowly. This disease affects people of both sexes and most are diagnosed between 40 and 60 years old.

Causes of Muscular Dystrophy

Muscular dystrophy is caused by mutations on the X chromosome. Each version of muscular dystrophy is due to a different set of mutations, but all prevent the body from producing dystrophin. Dystrophin is an essential protein for building and repairing muscles. Duchenne muscular dystrophy is caused by specific mutations in the gene that encodes the cytoskeletal dystrophin protein. Dystrophin makes up only 0.002% of the total proteins in striated muscle (made up of cylindrical muscle fibers), but it is an essential molecule for the overall functioning of muscles. Dystrophin is part of an incredibly complex group of proteins that allow muscles to function properly. The protein helps anchor various components within muscle cells and connects them all to the sarcolemma  the outer membrane. If dystrophin is missing or deformed, this process does not work properly and disturbances in the outer membrane occur. This weakens the muscles and can also actively damage the muscle cells themselves. In Duchenne muscular dystrophy, dystrophin is almost entirely absent; the less dystrophin produced, the worse the symptoms and etiology of the disease. In Becker muscular dystrophy, there is a reduction in the amount or size of the dystrophin protein. The gene that encodes dystrophin is the largest known gene in humans. More than 1,000 mutations in this gene have been identified in Duchenne and Becker muscular dystrophy.7

Diagnosis of Muscular Dystrophy

There are several techniques used for the definitive diagnosis of muscular dystrophy: The genetic mutations involved in muscular dystrophy are well known and can be used to make a diagnosis.

  • Enzyme tests  blood is tested for enzymes released by damaged muscles
  • Genetic tests  blood is tested for genetic markers for muscular dystrophy
  • Electromyography  a needle electrode is inserted into a muscle to test its electrical activity
  • Muscle biopsy  a muscle sample is tested for muscular dystrophy
  • Heart monitoring  electrocardiography and echocardiogram can detect changes in heart muscle. This is especially useful for diagnosing myotonic muscular dystrophy.
  • Lung monitoring  checking lung function can provide additional evidence

Treatment of Muscular Dystrophy

Treatment for muscular dystrophy is based on medication and various therapies that help slow the progression of the disease and keep the patient mobile for as long as possible.

Medications

The two most commonly prescribed medications for muscular dystrophy are:

  • Corticosteroids  although this medication can help increase muscle strength and slow progression, long-term use may weaken bones and increase weight gain
  • Heart medications  if muscular dystrophy affects the heart, medications for heart problems may be helpful

Physical Therapy

General Exercises  a series of stretching movements and exercises can help counteract the inevitable contractures of the limbs, as muscles and tendons shorten. Limbs tend to become fixed in position, and these activities can help keep them mobile for longer. Standard low-impact aerobic exercises, such as walking and swimming, can also help slow disease progression. Respiratory Assistance As the muscles used for breathing become weaker, it may be necessary to use devices to help improve oxygen supply at night. In severe cases, a patient may require assisted ventilation (breathing with the help of machines). Occupational Therapy Helps the individual become more independent. This therapy deals with skills for coping with problems, social skills, and how to access useful community services.

Mobility Aids

Canes, wheelchairs, and walkers.

Surgery

To help correct muscle shortening, treat scoliosis, correct cataracts, or address heart problems. Currently, there is no known cure for muscular dystrophies, but the combination of medical and physical treatments can improve symptoms and slow disease progression, giving people with this condition a better quality of life. Also see: Amniocentesis – What it is, When to Do It, and How it’s Done Photos: Madprime, amayaeguizabal