PATIENT INFORMATION
Myopathy (muscle disease)
Myopathy refers to diseases that affect skeletal muscles (muscles that connect to your bones).
What is myopathy?
Myopathy is a general term for disorders that affect the muscles themselves rather than the nerves supplying them. Causes include inherited muscle disorders (muscular dystrophies), inflammatory muscle diseases (myositis), medication-related muscle problems (for example, statins), hormonal disorders such as thyroid disease, and metabolic or mitochondrial disorders.
Symptoms may include:
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Muscle weakness, particularly around the shoulders and hips
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Difficulty climbing stairs or rising from a chair
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Trouble lifting objects overhead
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Muscle pain, cramps, or fatigue
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Episodes of raised creatine kinase (CK)
Why have I been referred for NCS and EMG?
These tests determine whether your symptoms are due to a muscle disorder rather than a nerve problem, identify the pattern of muscle involvement, help distinguish between inherited, inflammatory and other types of myopathy, and guide further investigations such as blood tests, genetic testing, MRI, or muscle biopsy. They provide functional information that complements blood tests and imaging.
What to Expect During the Test
Nerve conduction studies are often performed first to exclude neuropathy or a neuromuscular junction disorder; results may be normal in many muscle disorders.
EMG is the key part of the assessment: a very fine needle analyses the electrical activity of selected muscles, and characteristic findings can suggest a muscle disorder and identify the most appropriate next investigations. Read more about NCS/EMG.
Summary
Myopathy refers to conditions that directly affect the muscles, leading to weakness, fatigue, and difficulty with everyday activities. NCS and EMG help determine whether the problem lies in the muscles, nerves, or neuromuscular junction, and the results guide further investigation and treatment tailored to the underlying cause.