The forearm is comprised of two long bones, the radius and the ulna. According to the American Academy of Orthopaedic Surgeons, a buckle, or torus, fracture is caused by the compression of one side of the bone pushing against the other side, bending the bone, but not breaking it. This type of fracture is seen commonly in a child's wrist and is considered an incomplete fracture.
Deformity
Because a child's bones are soft, an actual breaking of the skin by the bone will not be seen. However, swelling and injury to the fat pad may be evident as changes occur to the soft tissues at the site. The University of Hawaii maintains that a torus fracture occurs due to axial compression or impact. On an x-ray this will show as a bending of one side of the bone and a break on the other, giving a bowed appearance.
Pain
The University of Hawaii gives three differences between a child's arm and that of an adult's. The outer lining of the bone, or the periosteum, is thicker, making it more stable than an adult's, the growth plates are still evident and the bones are less dense and more porous, making them less likely to break if bent or compressed. Due to these features, the arm may not appear broken, but pain is present at or near the site of the fracture. Movement of the limb, hands or fingers may be extremely uncomfortable.
Site
"Emergency Radiology" states that one of the most common sites prone to buckle fractures is the wrist. When falling, people are likely to put their hands and arms forward to break the fall. Because buckle fractures are extremely common in children, the physician will usually look to the hands or wrist first for signs of trauma if the child's history includes a recent fall.
