Muscle Disorders (Myopathies) General Information Dermatomyositis Facts About Myopathies Inclusion Body Myositis Juvenile Dermatomyositis Kearns-Sayre Syndrome Mitochondrial Myopathies Myopathy Myotonia Congenita Stiffness, Cramps and Twitching Medication Immune Globulin Intravenous Diagnostic Tests Ultrasound-Musculoskeletal Surgical and Other Procedures Muscle Biopsies Clinical Trials American Autoimmune Related Diseases Association Muscular Dystrophy Association Myositis Association of America Myotubular Myopathy Resource Group National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) Nemaline Myopathy Foundation United Mitochondrial Disease Foundation Clinical Trials: Muscular Diseases Clinical Trials: Musculoskeletal Diseases Clinical Trials: Myopathies Clinical Trials: Myopathy Recommended Support Groups