Most of the time, if you fracture a bone, it’s because of a fall or trauma. Or if you over-exercise, you can get a stress fracture. But there’s another type of fracture that can develop sometimes. It’s called an avulsion fracture, and it happens when your ligaments or tendons pull a small piece of bone away from the rest of the bone.
“People tend to think of bones as the ‘hardest’ or ‘strongest’ structures in the body,” said Cody Petrie, MD, a sports medicine physician at Banner Health in Phoenix, AZ. “But with avulsion fractures, we see that, in some ways, ligaments and tendons are actually stronger than the bones themselves.
Avulsion fractures can occur in many parts of your body, and you’ll often find them in the hip, elbow or ankle. “They can be large or small,” Dr. Petrie said.
Young athletes are at risk
Children and adolescents are at higher risk than adults for avulsion fractures. That’s because the growth plates in their bones are still open, and those sites are weaker than fully fused bone. So, the ligaments or tendons can place enough force on the growth plate to cause an avulsion fracture.
The demands of sports put more stress on ligaments and tendons. Sports and activities that require sudden changes in direction, such as football, ballet, gymnastics and skiing, are more likely to trigger avulsion fractures. These fractures are three to five times higher in boys than girls.
Tips for preventing avulsion fractures
Kids who play sports can take these steps to reduce the risk of fractures:
- Maintain flexibility.
- Warm up with high-quality, dynamic exercises.
- Learn appropriate body mechanics (position of the body when moving) for their sports.
- Use good form when running, throwing and participating in sports.
- Be careful not to overtrain, which can stress their bones.
“These types of injuries are much less common in adults, but adults can take the same steps to reduce their risk,” Dr. Petrie said.
Avulsion fracture symptoms
With an avulsion fracture, you can expect symptoms similar to other fractures or broken bones:
- Possibly bruising or discoloration
And, because of the pulling of ligaments and tendons, you could also experience weakness in the affected area.
Diagnosing avulsion fractures
If your child has symptoms of an avulsion fracture, you’ll probably want to get an exam right away at an urgent care center or emergency room. Medical professionals can usually diagnose these fractures with a medical history, physical exam, and possibly X-ray or ultrasound imaging.
Treating avulsion fractures
You may want to see a sports medicine or orthopedic specialist for treatment. Like other types of fractures, avulsion fractures heal with time and rest. “It often takes bones a minimum of four to six weeks to heal, and some fractures can take longer,” Dr. Petrie said. Sometimes, you’ll need to immobilize the joint, so the tendons and ligaments don’t pull on the bone while it’s healing. You may need a cast or walking boot, and you may need to use crutches.
In rare cases, you could require surgery to treat an avulsion fracture. Surgery could be necessary if the avulsion fragment is too far away from the main bone to heal on its own, so it needs to be fixed back in place.
Your health care team will likely talk to you about what caused the fracture so you can take steps to prevent another one from occurring. “Specific treatment can address the underlying reasons that caused the injury in the first place,” Dr. Petrie said.
The bottom line
Avulsion fractures can develop when a tendon or ligament pulls a piece of bone away from the main bone. They are most common in young athletes, who stress the growth plates where their bones are weaker. If you would like to talk to an orthopedic or sports medicine specialist about preventing avulsion fractures, connect with Banner Health.