Several thigh muscles attach to the pelvis. An avulsion is a tearing away of a body part from its point of attachment. Avulsion fractures occur when tendons, which attach muscles to bones, pull a part of the bone away. This occurs after a sudden, forceful contraction of the muscle. Pelvic avulsion fractures are often seen in teen-age athletes.

Avulsion fractures cause pain at the attachment of the muscle, either in the front of the hip area or the buttock. Swelling and tenderness are noted by the physician. An x-ray usually shows the avulsed bone fragment.

Avulsion fractures are treated with rest for 4 to 6 weeks. The athlete may be required to use crutches. Most heal well, but surgical repair is occasionally needed if a large piece of bone has been pulled far away from its original position

Once the bony avulsion has healed, the goal of rehabilitation is to return the athlete to their sport as quickly and safely as possible. When full range of motion of the leg has returned, and the athlete is able to run, jump, and cut on both legs without pain, he/she can return to full sporting activities.

Avulsion fractures can be prevented. The most common cause of avulsion fractures are tight muscles, so appropriate warmup and stretching is necessary. The muscles most commonly involved are that of the thigh, hamstring, and groin muscles, and these areas must be properly addressed prior to all sporting activity.