<unk>  <unk>  () (sometimes called sporadic<unk> , sIBM) is the most common inflammatory muscle disease in older adults. The disease is characterized by slowly progressive weakness and wasting of both proximal muscles (closest to the<unk> 's midline) and distal muscles (the limbs), most apparent in the finger flexors and knee extensors.<unk>  is often confused with an entirely different class of diseases, called hereditary inclusion<unk>  myopathies (hIBM). The "M" in hIBM is an abbreviation for "myopathy" while the "M" in<unk>  is an abbreviation for "myositis". In<unk> , two processes appear to occur in the muscles in parallel, one autoimmune and the other degenerative. Inflammation is evident from the invasion of muscle fibers by immune cells. Degeneration is characterized by the appearance of holes, deposits of abnormal proteins, and filamentous inclusions in the muscle fibers. sIBM is a rare disease, with a prevalence ranging from 1 to 71 individuals per million. Weakness comes on slowly (over months to years) in an asymmetric manner and progresses steadily, leading to severe weakness and wasting of arm and leg muscles.<unk>  is more common in men than women. Patients may become unable to perform activities of daily living and most require assistive devices within 5 to 10 years of symptom onset. sIBM is not considered a fatal disorder, but the risk of serious injury due to falls is increased. Death in<unk>  is sometimes related to malnutrition and respiratory failure. There is no effective treatment for the disease.
Inclusion body myositis
Dermatomyositis
Nemaline myopathy
Polymyositis
Dermatopolymyositis
Centronuclear myopathy
Hereditary inclusion body myopathy
Brody myopathy