Johns Hopkins All Children’s Sports Medicine - Myositis Ossificans

Myositis ossificans is a reaction to a bruise in a muscle that has been injured. During the healing of the bruise, calcium can become deposited in the bruise causing a hard bone like structure within the muscle.

The exact reason why this happens is unclear but it is known to happen more often in athletes with repetitive trauma to the same area before the bruised muscle has appropriate time to heal.

This condition occurs most commonly in contact sports and is most commonly seen in the quadriceps muscle of the thigh and the area of the upper arm.

This condition presents as a hard and painful area located at the site of a bruise which has been healing for 2-4 weeks.

In most athletes, if the area is allowed to heal appropriately this calcification or bone formation will resorb and go away on its own.

Evaluation of this condition includes getting X-rays to monitor the progression of the calcium formation. The most important aspects of therapy are avoidance of further trauma in the area affected and physical therapy to maintain motion in the affected extremity.