Myopathy/Inflammatory Myopathy

Myopathy refers to diseases affecting the muscles that control voluntary movement in the body and cause muscle weakness. Myopathies can be genetic (such as muscular dystrophies). Others, known as inflammatory myopathy (myositis), are acquired later in life due to autoimmune disease. Myopathy can affect muscles of the eyes, face, arms, legs, trunk, swallowing, and breathing.  

Myopathies are grouped as follows: 

Congenital myopathies: characterized by developmental delays in motor skills; skeletal and facial abnormalities are occasionally present at birth 

Muscular dystrophies: characterized by progressive weakness in voluntary muscles; sometimes evident at birth 

Mitochondrial myopathies: caused by genetic abnormalities include Kearns-Sayre syndrome, MELAS and MERRF 

Glycogen storage diseases of muscle: caused by gene mutations include Pompe's, Andersen's and Cori's diseases 

Myoglobinurias: caused by disorders in muscle metabolism include McArdle, Tarui, and DiMauro diseases 

Dermatomyositis: an inflammatory myopathy of skin and muscle 

Myositis ossificans: characterized by bone growth within muscle tissue 

Familial periodic paralysis: characterized by episodes of weakness in the arms and legs 

Polymyositis, inclusion body myositis, and related myopathies: inflammatory myopathies of skeletal muscle 

Neuromyotonia: characterized by alternating episodes of twitching and stiffness 

Stiff-man syndrome: characterized by episodes of rigidity and reflex spasms 

Common muscle cramps and stiffness

Tetany: characterized by prolonged spasms of the arms and legs 

A variety of tests help us find patterns of muscle weakness such as your ability to rise from a chair and walk, and coordination and reflexes. Imaging, neurological and blood tests determine if you have any endocrine abnormalities, heart problems, mental dysfunction, muscle atrophy or skin rashes. We might suggest a serum enzyme test to measure the amount of muscle protein circulating in your blood. Electromyograph will show the extent to which certain muscles are weakened and a muscle tissue biopsy can discover cell and protein abnormalities. 

Treatment for myopathy varies depending on the type and specific cause. Treatments range from those that address your symptoms to those that target specific causes of the condition. Most myopathies require the use of supportive services, such as physical and occupational therapy, pulmonary medicine, cardiology, dietary management, and speech/swallowing therapists. Certain types of myopathies can be treated with immunotherapies. Surgical treatment of spine and limb deformities is used in long-standing cases. 

A thorough and accurate diagnosis of your symptoms is key to treating and managing your specific condition. 

Houston Methodist’s expert team will design a personalized treatment plan to reduce the impact of myopathy on your daily life and improve your physical and emotional well-being.