Myopathy
What is Myopathy?
A myopathy refers to a group of disorders that primarily affect the muscles themselves, leading to muscle weakness, impaired muscle function, and potential muscle wasting. These conditions arise from abnormalities or dysfunction within the muscle fibers, impairing their ability to contract and perform their intended functions.
Myopathy Symptoms
Myopathies cause various combinations of weakness and/or pain. Clinical presentations of myopathies vary widely. Common symptoms include muscle weakness, fatigue, decreased muscle endurance, muscle pain or cramps, and in some cases, muscle stiffness. The distribution and severity of muscle involvement can differ significantly, with some myopathies predominantly affecting specific muscle groups or being more generalized in nature.
Though some begin with weakness in the hands and feet, most myopathies begin with weakness closer to the torso, especially in the shoulders, hips, thighs, and neck.
The first symptoms most people notice are difficulty walking up stairs and/or brushing their hair or teeth. Sometimes, myopathies cause pain in these areas, and some myopathies are associated with a rash.
Depending on the specific type of myopathy, additional features may be present. For example, in some myopathies, there may be associated muscle hypertrophy (increased muscle size) or muscle wasting (atrophy). Certain myopathies may also be associated with other systemic manifestations, such as cardiac abnormalities or involvement of other organ systems.
What Causes Myopathy?
Myopathies can have various causes, including genetic factors, autoimmune reactions, metabolic disturbances, toxic exposures, infections, and certain medications. The specific underlying mechanisms differ depending on the type of myopathy. Some myopathies result from genetic mutations that affect the structure or function of proteins involved in muscle contraction, while others may involve immune-mediated inflammation or disruptions in energy metabolism within the muscle cells.
- Some medications, especially cholesterol-lowering drugs, can damage muscles.
- Alcohol is toxic to muscles and can cause myopathy.
- Many myopathies, including dermatomyositis and polymyositis, are the result of inflammation from an overactive immune system.
- Many others are genetic, with the disorder inherited from earlier generations.
- Finally, some medical conditions, such as thyroid disorders, can result in myopathies.
How is Myopathy Diagnosed
During the initial consultation, we obtain a detailed description of the patient’s current symptoms and prior illnesses experienced by the patient and family members. Diagnosing myopathies typically involves a comprehensive assessment that includes a thorough medical history, physical examination, laboratory tests, and specialized investigations. Blood tests may be conducted to evaluate muscle enzyme levels (such as creatine kinase), detect specific autoantibodies, or assess metabolic parameters. Electromyography (EMG), muscle biopsies, genetic testing, and imaging studies can provide further insights into the specific type and extent of the myopathy. Diagnosis also includes:
- A review of current and prior medications.
- A complete neurologic exam, focused on detailed testing of muscle strength, will follow.
- If a myopathy is a possibility, we order blood tests and possibly an electromyogram and nerve conduction studies (EMG/NCS, detailed nerve and muscle testing).
- While muscle biopsies are sometimes needed, the advent of newer blood testing for specific conditions, especially genes, helps many individuals avoid biopsies.
At the Pacific Brain Health Center, we are able to offer complete exams, EMG/NCS testing, and blood testing. If a biopsy is needed, our PNI surgery colleagues are able to provide that service as well.
How is Myopathy Treated?
Treatment options are varied and depend on the cause.
- If the myopathy is the result of a medication, stopping the medication usually clears up the problems.
- If an underlying medical condition is causing the muscle problems, treating that underlying condition usually leads to relief.
- In inflammatory myopathies, treatments aimed at reducing inflammation and sometimes underlying immune overactivity are needed.
- Regardless of the cause, patients usually benefit from physical and/or occupational therapy, available at nearby at Providence Saint John’s Performance Therapy.
Myopathy Care Team
The specialist at the Pacific Brain Health Center in California are trained experts ready to evaluate and treat you, helping you to stay involved with the activities and people who matter to you.