What is myositis and what are typical symptoms?

Muscle inflamatiin: Myositis means muscle inflamation. It can occur where a muscle has been injured.

Proximal Weakness: Myositis means, literally, inflammation of muscles. The primary symptom is insidious (slow/progressive) weakness of muscles closest to the body, such as shoulders and thighs. If left untreated, weakness can progress to point where one is unable to stand without assistance, finds it very difficult to climb stairs, and unable to raise arms. Pain can be present but weakness is primary symptom.