Myositis ossificans (MO) is an inflammatory pseudotumor of the muscle that may be mistaken clinically and even histologically for a malignant soft tissue tumor. The aim of this article is to report the imaging characteristics of MO, the emphasis being on the early diagnostic clues. USG can be used at an early stage to reveal the 'zone phenomenon,' which is highly suggestive of MO. A short course of nonsteroidal anti-inflammatory drug therapy may be an efficient treatment for early MO.
Keywords: Myositis ossificans; ossification; tumor; ultrasonography; zone phenomenon.