A muscle disease is any disease that affects the human muscle system.
Primary muscle diseases result from abnormalities of the muscles themselves.
Secondary muscle diseases are resulting from another condition that may have triggered or caused the muscle disease.
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Because of this, these diseases may eventually result inmuscle wasting, or loss of muscle mass.
This may involve loss of strength and function in one or more muscles.
Sometimes paralysis may occur.
This article discusses primary and secondary muscular system diseases.
It also explains the symptoms, causes, diagnosis, and treatment of muscle diseases.
You even have muscles that you are not aware of.
Examples include the muscles that control your posture and contract blood vessels.
There are over 600 muscles in the human body.
There are also three recognized muscle types.Each of the three types has its own specific functions.
Recap
Each muscle bang out serves a specific purpose.
You walk because of skeletal muscles.
You digest food because of smooth muscles.
Your heart beats because of cardiac muscle.
Different muscle types work together.
When you run, you use your skeletal muscles to move your limbs.
Your cardiac muscle makes your heart beat, and your smooth muscles help you breathe.
PM is mostly seen in people over age 20, more often in females.
PM is marked by muscle inflammation and weakness.
A person with this condition may experience falls and problems getting up from falls.
Other symptoms include chronicdry coughand/ordifficulty swallowing.
PM has no known cause, and there is no cure for the condition.
Fortunately, the condition is treatable.
Dermatomyositis
Dermatomyositis(DM) is a rare inflammatory muscle disease.
It can affect people of any age or sex, though it’s more often seen in women.
Common symptoms of DM include:
Like other inflammatory myopathies, the cause is unknown.
There is no cure, but the condition can be managed with medications and other therapies.
Muscular Dystrophy
Muscular dystrophy(MD) is a group of inherited myopathies.
These conditions all cause muscle loss and weakness.
Some types of MD appear in infancy or childhood.
Others may not appear until middle age or even later.
Symptoms are specific to the punch in of MD.
They can vary based on the muscle groups and people they affect.
All forms of MD grow worse with time.
Most people lose their ability to walk.
There is no cure for MD, but symptoms can be treated.
Treatment can also prevent complications.
Treatments include:
Some people with MD have mild symptoms that progress slowly.
Others have symptoms that are severe and disabling.
Myasthenia Gravis
Myasthenia gravis(MG) is anautoimmuneneuromuscular disease.
Neuromuscular diseases are brought on by problems with how the nerves and muscles work together.
This interferes with nerve signals to the muscles, causing muscle weakness.
MG is the most common chronic autoimmune neuromuscular disorder.
It affects 20 out of every 100,000 people.
The primary symptom of MG is weakness in the voluntary skeletal muscles.
There is no cure for MG, but treatment can control the activity of the immune system.
The outlook for MG is different for each person.
Some people will have only mild symptoms.
Others may become disabled.
Early treatment can limit the diseases progression.
Amyotrophic Lateral Sclerosis
Amyotrophiclateral sclerosis(ALS) is also called Lou Gehrigs disease.
This group of rare neurological diseases affects the nerve cells in the brain and spinal cord.
ALS affects the muscles responsible for voluntary movement.
Most cases are diagnosed in people ages 40 to 70.
Treatment can help control symptoms and prevent complications.
Typical life expectancy, though, is only a few years after diagnosis.
Treatments for ALS include:
In severe cases, patients may need nutritional and breathing support.
Rhabdomyolysis
Rhabdomyolysisis a disease that causes the breakdown of skeletal muscle.
This breakdown causes myoglobin to release in the bloodstream.
Myoglobin is a protein that stores oxygen in the muscles.
Too much myoglobin in the blood can lead to kidney damage.
Causes of rhabdomyolysis include:
Treatment depends on the severity of symptoms and the presence of complications.
Kidney damage from rhabdomyolysis may not be reversible.
Cardiomyopathy
Cardiomyopathy, also called heart muscle disease, is a disease that affects cardiac muscle.
Incardiomyopathy, the heart becomes abnormally enlarged, thickened, and/or stiff.
This makes it harder for the heart muscle to pump blood efficiently.
Eventually, this may lead to heart failure.
Blood and fluids may back up into the lungs and other parts of the body.
Cardiomyopathy can also cause abnormal heart rhythms and heart valve problems.
Sarcopenia
Sarcopenia, also called geriatric muscle disease, is common in older adults.
This risk is 53% in those over age 80.
Sarcopenia causes loss of muscle mass and strength.
Risk factors include:
For some people, muscle weakness appears suddenly.
For others, it comes on slowly over many years.
Older adults become more susceptible to sarcopenia as they age.
Poor nutrition, chronic disease, and reduced hormone levels are thought to contribute to this risk.
Secondary Muscle Diseases
Sometimes, muscle diseases appear as a result of other more serious health conditions.
Secondary muscle diseases are diagnosed the same way as primary conditions.
Treatment involves managing the underlying cause and treating the secondary condition.
Muscular System Disease Symptoms
One of the first signs of muscle problems is muscle weakness.
This means the muscle lacks strength and cannot do its job.
Many different diseases can cause muscles to become weak.
Muscle pain that improves with home therapies is usually nothing to worry about.
Pain from severe injuries or a serious illness that affects the whole body often requires medical care.
Some muscle diseases are genetic.
Some muscle diseases are autoimmune diseases, which occur when the immune system attacks its own healthy muscle tissues.
Sometimes, the cause of the muscle disease is unknown.
An EMG measures electrical activity in the muscles.
This can help identify neuromuscular abnormalities.
Once the needle is in place, the patient is asked to contract or relax muscles.
The electrode detects electrical activity.
A nerve conduction velocity test may be done with an EMG.
This test measures the speed of the electrical impulses moving through your nerves.
This can help determine if the cause of symptoms is muscle disease or a nerve disorder.
If your doctor suspects you have a muscle disease, a muscle strength exam may be done.
This helps determine if there is muscle weakness or other muscle problems.
Additional testing may include:
Treatment of Muscle Diseases
Most diseases of the muscular system are incurable.
The good news is they can often be treated and managed.
Treatment goals may include relieving symptoms, delaying disease progression, and improving quality of life.
Treatment may include drug therapy.
This may include immunosuppressants, drugs that reduce or prevent the overactivity of the immune system.
These drugs may be used to treat some muscle and nerve diseases.
They may also be used for conditions that affect both the nerves and muscles.
Corticosteroidsmay be used for inflammation and other medications may be given to reduce muscle spasms and cramping.
Summary
Diseases of the muscles can occur on their own or due to other conditions.
Muscle diseases have many causes, including genetics and autoimmune conditions.
Sometimes, the cause is not known.
Muscle diseases are often diagnosed with a test that measures electrical activity in the muscles.
These disorders are usually incurable, but many of them can be managed.
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