Myopathy

Myopathy is a disease of the muscle in which the muscle fibers do not function properly. The name comes from the Greek for muscle and suffering, and it signals that the primary defect lies in the muscle itself rather than in the nerves or the brain. The usual result is muscle pain, weakness or early fatigue, and cramps, stiffness, spasm and contracture can accompany it. Long-standing myopathy may leave a muscle abnormally small through atrophy or abnormally large with a pseudoathletic look. Individual myopathies can be inherited, infectious, non-communicable or of unknown cause, and the disease may affect only muscle or form part of a systemic illness, as the mitochondrial myopathies do. The term is also used for capture myopathy in stressed wild and captive animals.