An avulsion fracture is damage to a bone where a tendon or ligament attaches to the bone. When an avulsion fracture occurs, the tendon or ligament tears off a piece of bone. Avulsion fractures can occur anywhere in the body, but are more common in some specific locations .
Avulsion fractures are more common in children than in adults. In adults, ligaments and tendons are primarily damaged, while in children, the bone can collapse before a ligament or tendon is damaged.
Children have a particularly weak point in the skeleton called the growth plate. This is an area of bone that is actively growing. In children, tendons or ligaments near the growth plate can stretch the growth plate hard enough to fracture .
Often an avulsion fracture occurs when a tendon is suddenly stretched with force as the bone moves in the opposite direction. An example is an injury to the fifth metatarsal bone , located outside the midfoot. The peroneal tendon is attached to the base of this bone.
Often when the foot is twisted, a strong contraction of the peroneal tendon pulls the foot in one direction, while a twisting force is exerted on the foot in the opposite direction. This leads to cracking of the bone where the tendon joins the bone. The good news is that these fractures almost always heal after a simple rest and time .
An avulsion injury seen on an X-ray can be confusing because it can often be associated with an old injury. Sometimes a small piece of bone has been detached from the body for a long time, and only when an X-ray is taken a few months or years later can a piece of bone be seen .
It is important not to seek treatment for something that does not require intervention. That's why it's so important to have a doctor who can interpret your X-rays and apply those results in the context of your injury history and exam results.
Very often, an avulsion fracture can heal without surgery. Only when the torn bone fragment is moved from its normal position by more than a few centimeters, surgery may be required .
Also, some avulsion fractures involve pieces of bone so small that they do not need to be repaired. For example, sprains of the ankle joint often produce small fragments. These injuries can usually be treated as an ankle sprain, as a small piece of bone does not really affect treatment decisions or patient outcome .
There are some concerns about treatment when an avulsion fracture affects a child's growth plate. Because growth plates are important for normal skeletal development, these injuries must be treated with care. If there is a concern that the growth plate is not positioned correctly, surgery may be done to flatten and stabilize the growth plate .
Surgery may not be necessary if the avulsion fracture is well aligned or if the patient is close enough to the growth plate closure that the injury does not cause long-term growth problems .
Frequently asked questions
It may take six weeks to six months for full recovery and full activity to resume. The exact time it will take will depend on the part of the body that is injured and the severity of the avulsion fracture.
Most growth plate injuries heal without interrupting growth if properly treated. However, sometimes a bony bridge forms along the fracture line. This can stop growth or cause an abnormal curvature of the bone. If the bone is found early, the doctor can repair it.
You should consult a hand specialist. Your finger will most likely be placed in a splint, which will allow it to remain stable, and you will be able to move it around a bit so as not to lose mobility in the long term. Surgery is sometimes required to insert the pins into the bone. Physical therapy is generally recommended.