Identifying fractures that are the result of child abuse is not easy, therefore it is vital that physicians be more comfortable in finding these types of fractures. Fractures, of any type, have been found in between 11 percent and 55 percent of children who were abused; most often, these children were under 3 years old. In an effort to find if one particular fracture is more common among abused children, researchers have found that they occur equally in the femur (thigh bone), tibia (lower leg), and humerus (upper arm). Although spiral fractures are only one of the most types of fractures seen in this group of children, researchers have suggested that children with this injury be watched for signs of abuse, especially if there was a delay in treatment.
Given the difficulties in determining if child abuse is present when children with this type of fracture come to the emergency room, the authors of this study wanted to identify the fracture patterns that result when a bone is twisted in different directions and is broken. The research was done using rabbit femurs because they are similar in structure and properties to human bones. The authors felt that this would help identify the effectiveness of standard x-rays in detecting spiral fractures.
Using 20 rabbit femurs, previously removed from the animal carcasses, the researchers applied twisting forces to break the bones. Seventeen of the fractures were spirals and 3 had several fragments (multi-fragmented). Following the fractures, the researchers glued the bones back together to mimic a minimally displaced fracture. X-rays were taken of the bones and 10 pediatric, orthopedic, surgical, emergency department, and radiology residents were asked to examine them.
Slightly more than half of the residents were able to make the identification:
Seven pediatric residents, 6 orthopedic, 6 radiology, and 5 emergency room residents were able to say how the bones were broken and in what direction they were twisted. Once they were given more information, they were all able to see how the break occurred.
The authors write that the doctors who can identify if a break has been caused by a twisting motion would be able to use this information in assessing the possibility of abuse.
In conclusion, the authors say that this study “was able to show the direction of the torsional force that produces a spiral fracture can be determined from the characteristic fracture pattern” on the x-rays.