Updated December 04, 2014.

Definition: Myositis ossificans is an unusual condition that often occurs in athletes who sustain a blunt injury that causes deep tissue bleeding. A typical story is a soccer player who is kicked forcefully in the mid-thigh, and develops pain and significant bruising.

The soft-tissues that were injured in the traumatic event initially develops a hematoma, and subsequently develop the myositis ossificans.


The word myositis ossificans means that bone forms within the muscle, and this occurs at the site of the hematoma. No one knows exactly why this occurs in some people.

The common concern when abnormal bone is seen on a x-ray is that there is a tumor within the soft-tissues. Fortunately, myositis ossificans has some typical clues that usually make it easily differentiated from a tumor. If there is any question about the diagnosis, repeat x-rays will be obtained several weeks later to ensure the bone mass is a typical myositis ossificans.

Treatment of myositis ossificans consists of:

• Rest
• Immobilization
• Anti-Inflammatory Medication

Rarely is surgical excision of the myositis ossificans warranted. If the myositis ossificans is removed before it is "mature," it will likely return. Therefore, most surgeons wait between 6 and 12 months before even considering removal. Furthermore, there is a chance of return even when removed very late. Generally, myositis ossificans is only removed surgically if it interferes with joint motion or if it is irritating a nerve.