An avulsion fracture is a type of fracture in which part of the bone is broken off or “avulsed” from the rest of the bone. While this might sound scary, these fractures are actually very easy to treat in most cases. The exception to this rule is extensive avulsion fractures, and certain types of fractures in children.
The word “avulsion” literally means “tearing.” These fractures are typically caused when so much force is exerted on a tendon or ligament that it pulls away, tearing off a chunk of bone along the way. In many cases, people have a tough time getting an avulsion fracture, because their muscles send signals to the body telling them to stop before they hurt themselves. Athletes, who push through such signals, are at risk of fractures. So are children, because their growing bones will break before their young tendons and ligaments will.
In a basic avulsion fracture, an X-ray of the site reveals that a small piece of bone has been torn away. By resting the affected area, icing it periodically, and using anti-inflammatory drugs to keep down inflammation and infection, the fracture can be treated. Sometimes, however, a large piece of bone is removed, or the bone is significantly dislocated. In these instances, surgery is required to address the fracture. In children, this type fractures can damage the growth plate of the bone, causing long-term damage unless surgery is performed.
These fractures are most typically caused by a jumping or throwing motion. They may feel more like torn or pulled muscles, since the muscle tissue is often damaged in the process. If an avulsion fracture is suspected, a doctor can take an X-ray of the area of the interest to determine whether or not a fracture has occurred, and to see how serious the fracture is. A simple recommendation of rest is sometimes the best prescription for this type of fracture.
When surgery is performed on an avulsion fracture, the goal is to reattach the piece of bone which has been torn away, and to address the associated torn ligament or tendon. Recovery periods can be lengthy for more serious fractures, as any trauma to the area can cause the fracture to recur, or make it worse, two outcomes which are most definitely undesirable. Athletes in particular tend to be at risk of re-damaging the fractures by getting back into training too soon — it's important to see a doctor to get the OK before taking up physical activity again.