Diagnosis: Myositis ossificans of the bilateral medial and lateral pterygoid muscles
The term myositis ossificans is the subject of some controversy and confusion. It is frequently used interchangeably with heterotopic ossification, which is defined as the formation of bone outside the skeletal system. However, myositis ossificans is more accurately classified as a type of heterotopic ossification in which heterotopic bone formation occurs within muscle or soft tissue.1,2 Given the possible soft-tissue involvement and lack of inflammation late in the disease, some authors think that the name myositis ossificans is also misleading. However, myositis ossificans will be used for our purposes.
Radiology Quiz Case 1: Diagnosis. Arch Otolaryngol Head Neck Surg. 2012;138(4):423. doi:10.1001/archoto.2012.62b