Possible pathogenic pathways of sIBM – multifactorial mechanisms involved. An inflammation pathway and a degeneration pathway constitute the two most popular theories for the pathogenesis of sIBM. Ageing is also considered an important factor contributing to mitochondrial dysfunction in result of oxidative stress in the muscle tissue. However, it is still not clear which is the primary cause of the disease, and how these potential pathways interact. Predisposing genes could also contribute to the development and progression of the disease.