Myopathy

Myopathy refers to primary muscle disorders causing weakness, hypotonia, and exercise intolerance. Etiologies include inherited, inflammatory, metabolic, and drug-induced causes. Pathophysiology involves structural, enzymatic, or mitochondrial dysfunction within muscle fibers. Diagnosis relies on clinical evaluation, laboratory testing (CK), electromyography, and muscle biopsy. Management is tailored to etiology, including supportive care, immunotherapy, or enzyme replacement; prognosis varies.