A case of non-traumatic myositis ossificans in quadriceps femoris

Myositis ossificans is a rare benign ossifying lesion in skeletal muscles which is commonly seen after trauma. However, it has been reported that myositis ossificans can be developed without any history of trauma and surgery. A 37-year-old female presented with a painful progressive swelling in her right femoral area, with no history of trauma or other diseases, which had been developed for 2 weeks. Initial X-rays were normal. An incision biospy specimen showed a lesion of fibroblastic tissue in which areas of osteoid and trabecular bone tissue, which was compatible with the early stage of myositis ossificans. The mass was excised totally and no signs of recurrence have been noted until now.