Fractures account for 10% to 15% of all childhood injuries.
Fractures may be more common than sprains, ligamentous injuries, due to the relative weakness of the physis, or growth plate.
Injuries to the physis may lead to long-term growth abnormalities or growth arrest.
Radiographs are more difficult to interpret in children than in adults, as the physis is radiolucent and there are secondary ossification centers.
The majority (75%) of physis fractures are Salter II fractures.
Up to 50% of fractures in children younger than 1 year may be due to nonaccidental trauma.
Orthopedic and sports-related injuries are one of the most common reasons for pediatric visits to the emergency department (ED). Approximately half of all children will fracture at least one bone during childhood, and it is estimated that up to 25% of children sustain an injury every year.1 Youth sports participation at earlier ages has been accompanied by a growing number of sports injuries. Studies suggest most of these injuries are related to falls, recreation, sports, or motor vehicle accidents, but the emergency physician should never forget to consider nonaccidental trauma. The diagnosis of pediatric orthopedic injuries is challenging because of growth plates and the difficulty of interpreting pediatric x-rays. The fractures most often missed during an ED visit are those involving the phalanges and metatarsals.2 With a better understanding of the growing skeleton, clinicians can improve the accuracy of their diagnoses leading to more optimal management, fewer complications, and better outcomes.3
The Immature and Growing Skeleton
The immature skeleton has many special characteristics to appreciate when comparing it to mature, adult bone. First, the growing bone is more porous and flexible which can lead to unique fracture patterns such as greenstick, torus (buckle), and bowing (plastic deformation). This allows the young skeleton to bend much further and absorb more force before a fracture occurs. The porous character of growing bone is why there is less comminution and propagation of fractures as seen in adult fractures.4
The growing bone is surrounded by a thick, active periosteum. It is not easily torn or stripped away when bones are fractured, so less displacement usually occurs. The periosteum can aid as a hinge during fracture reduction. This active periosteum is the primary reason fractures remodel so well and heal so rapidly in children making nonunion a rarity.
The most noticeable characteristic on radiographs of children is the presence of the radiolucent physis, or growth plate. It is radiolucent cartilage which gradually ossifies throughout childhood and adolescence. Clinicians must understand and recognize each bony region in addition to the physis when assessing orthopedic injuries (Fig. 29-1).
Illustrations of the humerus and femur demonstrating specific features of the immature skeleton.