What is Myopathy?
Myopathies are diseases that affect the nervous system. They cause damage to nerve cells, which leads to problems with movement, speech and other functions. Myopathic conditions may not necessarily lead to death. However, they are usually very debilitating and require a great deal of care and attention.
The term myopathy refers to any disease or condition that affects the nerves. There are several different types of myopathies, but all of them have one thing in common: they affect the brain and spinal cord. There are many conditions that can lead to myopathy, including:
The symptoms of myopathy are as varied as the conditions that lead to this disorder. There are several types of myopathy that present with specific symptoms. For example, with Duchenne muscular dystrophy (DMD), the disease severely affects the patient’s voluntary muscles starting at around age 3. As the disease advances, children are typically unable to walk independently or even stand. Ultimately, they need a wheelchair to get around and eventually their lungs become affected as well.
These children typically die in their teens.
Other types of muscular dystrophies present with different symptoms. In Emery-Dreifuss muscular dystrophy (EDMD), the voluntary muscles are typically weakened, but essential muscles continue to work and the patient is able to live a fairly normal life span. With polyneuropathy, the voluntary muscles are not severely affected, but patients typically experience numbness and weakness in their hands and feet.
With metabolic myopathies, the symptoms are usually related to specific organs. For example, in mitochondrial myopathy, patients may experience seizures, strokes and other problems directly affecting the brain and nervous system. In mitochondrial cardiomyopathy, the heart is typically affected. Patients may experience shortness of breath, dizziness and other heart-related symptoms.
As with many disorders and diseases, the symptoms of myopathy usually vary from patient to patient. Every condition has its own set of causes, complications and effects. It is important to seek immediate medical attention if you experience symptoms of myopathy, before it is too late.
What are the Causes of Myopathy?
There are many different causes for myopathy. As the term would suggest, most myopathies are caused by problems with the muscles themselves. However, there are many different causes of myopathy. These include (but are not limited to) metabolic, infectious, toxic and neurodegenerative disorders. In many cases, the specific cause of myopathy is never determined.
How is Myopathy Diagnosed?
If you think you or someone you know has myopathy, a physician should be consulted immediately. While there are several types of myopathy, the initial diagnosis will usually involve a battery of tests. The physician may begin by taking a complete medical history to see if you have any risk factors for myopathy. A physical exam will be performed to assess any symptoms you may be experiencing. Your doctor may also order blood tests to look for abnormalities in your bloodwork.
Once these initial steps have been completed, more specific tests may be ordered. For example, muscle weakness may warrant an electromyography (EMG) and/or nerve conduction velocity (NCV) test. These tests help your physician assess the electrical activity of your muscles and the conduction of signals along your peripheral nerves, respectively. Your blood may also be tested for certain biomarkers that may point to a specific diagnosis.
Depending on your age and symptoms, your physician may also order an MRI or CT scan of your brain and/or nerve conduction studies to assess the health of your nerves.
How is Myopathy Treated?
There is no cure for myopathy. However, various treatments can help to manage the symptoms of this disorder. As with any medical issue, it is important to maintain a healthy diet and exercise routine. Patients should also avoid medications, foods and activities that could worsen their condition.
If you are suffering from myopathy, your physician may recommend that you undergo physical therapy. During physical therapy, your muscles will be stretched and exercised to make them stronger and to help preserve muscle mass. Your physician may also prescribe medication to help with specific symptoms. For example, if you have a tremor, your doctor may recommend beta blockers to control the severity of the tremor.
In some cases, surgery may be recommended to repair damaged muscles, nerves or tissue. For example, a transverse myelitis patient may undergo an operation known as a selective dorsal rhizotomy (SDR). During this surgery, the damaged portion of the spinal cord is removed, improving the patient’s ability to walk.
What is the Prognosis of Myopathy?
The prognosis of myopathy varies from person to person. While some individuals live a relatively normal life with few or no complications, others may succumb to the disorder. The speed at which myopathy progresses can also vary. While some people may experience symptoms within days or weeks of the initial infection, others may not develop symptoms for several months or even years.
The prognosis also depends on the type and severity of the myopathy. For example, a patient with myasthenia gravis can be treated with medication to help reduce or eliminate their symptoms. A patient with inclusion body myositis may experience a steady decline in muscle function over time, but otherwise have a good quality of life.
However, some patients myopathy is so severe that it results in death. This is more common in patients with congenital myopathies, where the disorder is present from birth. Congenital myopathies also tend to have a poor prognosis.
What is the Cause of Myopathy?
The cause of myopathy can vary. In many cases, the cause is unknown (idiopathic). In other cases, the cause is an underlying condition or the result of an external factor. Some of these underlying conditions and external factors are discussed below.
Underlying Conditions Associated with Myopathy
There are various medical conditions that have been associated with myopathy. These conditions typically cause muscle weakness or other symptoms, and may only be identified through diagnostic testing.
There are several congenital myopathies that can affect adults. These conditions are present at birth and cause symptoms early in life. While some of these conditions can be treated, there is no cure.
CMD is the general term for a group of inherited muscle diseases that are present at birth or appear in infancy. These conditions cause muscle weakness and often affect the heart and other organs. CMD is broken down into four categories:
Imyopathic – patients experience muscle weakness but do not develop the eye problems associated with this disorder.
Dermatomyositis- patients develop a skin rash on the top layer of the skin as well as muscle weakness.
Dystrophy – this category includes ten diseases that cause muscle weakness and typically affect the heart and other organs.
Myasthenic – patients experience muscle weakness along with deteriorating eye muscles.
Other congenital myopathies that can affect adults include:
CAMN: Acute muscle weakness and eye problems are common with this condition. It is passed down through families including in males and females.
CMT: This condition involves the loss of muscle tissue and affects males more than females. There are several forms of this condition, including types 1 through 4 and others.
Congenital Fiber Type Disproportion: Patients experience a loss of muscle fibers, causing weakness in limbs and the trunk. It is sometimes referred to as Congenital Fiber Type Distribution.
Myotubular Myopathy: The most common symptoms of myotubular myopathy include muscle weakness and respiratory problems. It is sometimes referred to as Centronuclear Myopathy.
Thanatophoric Dysplasia: This condition involves severe defects in organs and other structures present at birth. There are many types of thanatophoric dysplasia.
Myopathy secondary to other medical conditions
There are a number of medical conditions that have myopathy as a secondary condition. For example, patients with cancer and liver disease can experience muscle weakness due to their condition. Treatment for the underlying condition and supportive care can help manage the symptoms of myopathy.
External Factors Associated with Myopathy
Drugs are a common cause of myopathy. The most common drugs that cause myopathy are cancer medications and immunosuppressants. Radiation therapy for cancer and multiple sclerosis can also cause muscle weakness. Other drugs that have been known to cause myopathy as a secondary condition include, but are not limited to:
Physiological Conditions that May be Associated with Myopathy
There are a number of physiological conditions that can cause temporary or permanent muscle weakness. These conditions include, but are not limited to:
Dehydration – severe dehydration can cause muscle weakness and other symptoms that are similar to myopathy.
Hypothyroidism – also known as underactive thyroid, this condition is caused by low levels of thyroid hormones.
Hypokalemia – this condition is caused by low levels of potassium in the blood.
Inflammatory myopathy – this condition involves inflammation in the muscle tissue.
Tumor – cancer that begins in the muscle tissue can cause severe muscle weakness and other symptoms of myopathy.
There are various treatment options for myopathy. Treatment options depend on the type of myopathy, the symptoms exhibited by the patient and their age or other health concerns.
Physical therapy can help increase strength and improve movement in patients who have myopathy. In some cases, a referral to a specialist in physical medicine and rehabilitation may be made. In children, physical therapy can help them gain movement and learn to walk.
Medications may be used to manage symptoms in some patients.
Surgery may be required for muscle weakness or other symptoms. Surgery may include transplantation of muscle tissue, tendon transfer or other procedures as needed.
Transplantation – muscle transplantation involves transferring muscles from another part of the body to improve function in parts of the body that are weak.
Muscle transfer – in some cases, a procedure known as muscle transfer can be done. This involves transferring muscle from one part of the body to improve function in parts of the body that are weak.
Tendon transfers – in some cases, a tendon transfer may be done. This involves transplanting a tendon from one part of the body to an area that could not otherwise be used for movement.
Gene therapy is being researched for the treatment of different types of myopathies. Rehabilitation and physical therapy can also be helpful. In addition to these treatment options, a healthy lifestyle is important for patients with myopathy. This includes following a nutritious diet, getting plenty of rest and avoiding drugs and alcohol.
A Word From Trusted Health Products
Here at Trusted Health Products, we stock a great selection of products that can benefit patients with myopathy. Products that may be of benefit include Calcium, RNA-Melatonin and Magnesium. To learn more about these products, click on the image below.
Read about Magnesium and Sleep, Calcium and Muscle Spasms, Calcium and Osteoporosis
PubMed Health: What is Myopathy?
Mayo Clinic: Myopathy Treatment
Mayo Clinic: Myopathy Symptoms
Verywell: Myopathy Causes, Symptoms and Treatment
Verywell: Muscle Diseases
Verywell: Polymyositis Treatment
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- Statin induced myopathy (S Sathasivam, B Lecky – Bmj, 2008 – bmj.com)
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