Myositis ossificans traumatica of the medial pterygoid

Myositis ossificans traumatica (MOT) is a non-neoplastic, heterotopic bone formation within muscle or fascia, presumably due to acute trauma, a burn, surgical manipulation, or repeated injury. A 36-year-old woman presented with progressive limitation of mouth opening over the past 5 months. Computed tomography revealed an irregular ossified mass attached to the medial aspect of the left ramus, extending to the medial and lateral pterygoid plates. MOT of the medial pterygoid is rare, with only four previously reported cases in the English language literature. Surgical excision of the ossification is the main treatment modality. The authors were able to establish a cleavage plane of 3 cm between the bony mass and the medial surface of the ramus. Abdominal fat was placed as an interpositional material to prevent fibrosis and heterotopic bone formation.