Where do avulsion fractures occur?
Avulsion fractures can occur anywhere in the body, but they are more common in some areas. For example, we commonly see avulsion fractures around the pelvis.
Avulsion fractures are also more common in children than adults. In adults, the ligaments and tendons tend to be injured, whereas in children the bone may fail before the ligament or tendon is injured. Children have a particularly weak point in their skeleton called the growth plate. This is the area of bone that is actively growing. In children, tendons or ligaments near a growth plate can pull hard enough to cause the growth plate to fracture.
What is the treatment of an avulsion fracture?
Most often, an avulsion fracture is treated as a soft-tissue injury. For example, if a patient has an avulsion fracture of the hamstrings attachment on the pelvis (an ischial tuberosity avulsion), it can be treated in a similar manner to a hamstring tear. Only in avulsion fractures where the bone is pulled more than several centimeters from its normal position does surgery need to be considered. Usually these injuries can be treated without surgery.
Another example commonly seen is a patient with an ankle sprain. The ankle ligaments that were damaged often pull off a small piece of bone from its attachment site. Again, these injuries are treated as an ankle sprain, as the small piece of bone really does not affect the treatment decisions or outcome of the patient.
What about the treatment of avulsion fracture in children?
This is a little more complicated. As described previously, avulsion fractures in children usually occur in the area of a growth plate. Because growth plates are important for normal skeletal development, these injuries must be carefully treated. If there is concern that a growth plate is not correctly positioned, surgery may be performed to align and stabilize the growth plate.
Surgery may not be needed if the avulsion fracture is well aligned, or if the patient is near enough to growth plate closure that this injury will not cause lasting growth problems.
Last updated: 03/10/2006
- Metzmaker JN, Pappas AM. "Avulsion fractures of the pelvis." Am J Sports Med. 1985 Sep-Oct;13(5):349-58.