Is it really broken?

April 04, 2016

Childhood bone fractures are a common occurrence. Many of these fractures are overt and easily identified on an X-ray. However, some fractures that occur in children can be fairly subtle on an X-ray and in their physical appearance. That’s where pediatric expertise can be helpful in sorting things out.

At times, it may be hard to believe that a child really has fractured a bone because the injury doesn’t seem very impressive. At other times, it’s obvious there is an injury when examining the child, but no fracture can be seen on an X-ray.

Parents may hear that their child has a “buckle” fracture, that there is some fluid around the bone or that there might be an injury to a growth plate. Each of these describes a bone injury that is specific to children’s bones.

Children’s bones are softer than adult bones, easier to break but also more pliable. This can result in fractures that are “incomplete.” The incomplete nature of these injuries allows them to be more stable and usually not likely to tilt or shift during healing. They also heal more quickly than complete fractures.

Buckling bones

This is an example of a buckle fracture of a radius, down by the wrist.

A “buckle” fracture is the most commonly seen incomplete fracture. This fracture is a result of one side of the bone buckling or wrinkling as it fails in compression, while the other side of the bone remains intact. Buckle fractures are sore when you push on the injured area, or when a child tries to bear weight with the injured limb.

The image to the right is an example of a buckle fracture of a radius, down by the wrist.

Often, there is not much swelling or bruising, and pain can be controlled after the first day or two by limiting the child’s activity. These fractures heal fairly quickly, in three to four weeks, and can be treated based on symptoms such as swelling and pain. We often put a cast on a buckle fracture for comfort and protection, but Velcro braces or splints can be useful as well.

Subtle fractures

Other times, bone injuries can be more impressive upon examination, with swelling, bruising, pain and limited mobility. But X-rays may not show an obvious fracture. Frequently, these injuries have to be treated as if there is a fracture, usually immobilized with a splint or a cast.

If there is a fracture, it will become more evident on an X-ray during healing, seen best 10 to 14 days after the injury. This is called an occult fracture. What might have been a tiny, essentially invisible crack on the initial X-ray becomes much more obvious when the layering of healing bone, or periosteal reaction, develops along the sides of the injured bone.

The images below show a distal humerus, the most common place for pediatric elbow fractures.

These images show a distal humerus - the most common place for pediatric elbow fractures - right after the injury (left) and two weeks later (right); the healing bone is highlighted.

The X-ray on the left shows the bone right after the injury. The X-ray on the right shows the bone two weeks later and the arrow is pointing to the periosteal reaction, or healing bone.

At the time of the injury, it may be difficult to differentiate a very subtle bone fracture from a sprain or injury to a ligament. Fortunately, in most instances, the treatment would be the same for either a sprain or a subtle fracture.

Bent bones

Another type of incomplete fracture is called a greenstick fracture. In this injury, one side of the bone is broken or cracked, while the other side is bent. These injuries are also stable and fairly quick to heal.

They may, however, require further treatment to address a residual change in the shape of the injured limb, if the “bent” but not completely broken bone interferes with function. This can occur, for example, with the rotation of the forearm.

Careful evaluation for a definitive diagnosis

Evaluating injuries in children requires a careful clinical examination, and attentive assessment of X-ray images. At times, bone injuries need to be treated based on symptoms, with follow-up exams and potential X-rays to help make the definitive diagnosis.

If you have questions about a possible pediatric bone injury, call 206-215-2700 to schedule an appointment with a specialist, or visit Swedish Pediatric Orthopedics online.

Topics: Kids, Orthopedic