OHSU

Myopathy and Myositis

What Are Myopathy and Myositis?

The word myopathy means "disease of muscle." Myopathies are diseases that cause problems with the muscles that control voluntary movements (muscles you can control).  These problems range from stiffness (called myotonia) to weakness. They can be mild, moderate or severe.

Myopathies we treat include:

  • Mitochondrial myopathies
  • Metabolic myopathies such as Pompe, Debrancher and McArdle's diseases

Myositis is the term for any one of a group of inflammatory muscle disorders. These almost always cause weakness and can cause muscle swelling and pain.

Symptoms of Myositis

Early symptoms of myositis may include:

  • Difficulty getting up from a chair, climbing steps or lifting your arms
  • Falling
  • Getting very tired after standing or walking for a while
  • Loss of strength throughout the body

Myositis can sometimes cause difficulty swallowing or breathing.