Wrist fractures account for 30 percent of all fractures that occur in children, reports the American Academy of Orthopaedic Surgeons. Buckle fractures, which are also called torus fractures, are a specific type of wrist fracture that only happens during childhood. Buckle fractures are the most common wrist fracture in children.
Long bones in the forearm develop from growth plates located near the end. The growth plates are uncalcified cartilage regions where the bone-manufacturing and support cells are rapidly dividing. The growth plate appears as a clear area extending across the bone on x-rays. Bones grow in length and width from the growth plates, which is not as strong as regular bone.
The wrist is composed of two long bones, the radius and ulna. The radius is underneath the thumb and the ulna is on outside of the arm. Eight small carpal bones move across the radius and ulna allowing the wrist to bend back and forth, and side to side. Turning the hand rotates the radius around the ulna near the elbow. Medical professionals refer to the palm side of the wrist as the volar surface. The upper side of the wrist is called the dorsal surface.
Buckle fractures typically occur when a child falls and lands on an outstretched hand. Children with this injury commonly complain of wrist pain and refuse to use the arm. The child may identify one area of the wrist as the most painful. The affected arm is characteristically not obviously deformed.
With a torus fracture, the forearm bones compress creating a "buckle" or bump on the dorsal surface of the bones, which can be seen on x-ray. The opposite side of the bone appears normal.
Several other types of wrist fractures can occur in children. Greenstick fractures cause the bone to bend on the opposite side. A Galeazzi fracture of the radius has both sides of the bone broken and the ulna may be displaced. Both bone fractures may have fracture ends displaced, or out of alignment. Growth plate fractures, which are also called physeal or Salter fractures, go through part of the forearm growth plate.
With a buckle fracture, the arm may be put in a cast for 3 to 6 weeks. However, some doctors prefer to splint the wrist. No difference in healing of wrist buckle fractures has been seen between casts and splints. As children’s bones grow, they remodel. Within roughly a year of a buckle fracture, there is typically no sign of the prior injury in the forearm bones.