Muscle diseases ; approach for proper diagnosis and management

Abstract

Muscles produce contraction and relaxation to make force and motion of animals, and function as one of major energy storage. Thus, “muscle disease” is defined as disorders of muscle resulting in motor impairment with dysfunction of contraction or relaxation.

Electrodiagnostic studies are most important to confirm the presence of muscle diseases ; electromyography (EMG) to identify a decrement of motor units in myopathy, and repetitive nerve stimulation studies and single fiber EMG to identify instability of neuromuscular transmission in neuromuscular junction disorders.

It is easy to understand the pathogenesis of muscle diseases to classify as follows ; exogenous, systemic, immune–mediated, dysfunction of membrane excitability, dysfunction of energy metabolism, structural abnormality.

Recently, treatable myopathy identified among patients with chronic progressive weakness. Improvement of patient care and development of therapies are in progress. It is important to diagnose properly to provide accurate management and therapy for patients with muscle disease.