Pediatric Orthopedic Trauma

Musculoskeletal trauma is the most common medical emergency in children. In children ages 1–14 years, injuries are the leading cause of death, more than from all other causes combined. However, not all orthopedic injuries sustained by children are life threatening. The chance of a child sustaining a fracture before age 16 is 50% for boys and 25% for girls. It has been estimated that 1–2% of children present with a fracture each year, with peak incidence at 10–14 years. As participation in sports and other recreational activities increases, the number of fractures is likely to increase. In two studies looking at pediatric orthopedic practice management, fracture treatment (both operative and nonoperative) accounted for approximately one-third of the total work-related relative value units and 44% of operative volume. In another study the most common fracture-related operations were performed on the elbow (23%), tibia (12%), femur (9.8%), forearm (5.5%), and distal aspect of the radius (5%). However, pediatric fractures treated in the emergency department (ED) typically involve the forearm, hand, or wrist, are treated with simple closed reduction, and do not require admission.

Patient gender, age, climate, time of day, sleep deprivation, obesity, and the social situation in the home have been shown to have an impact on the frequency of orthopedic injuries. In children, boys sustain fractures at 2.7 times the rate of girls. However, as girls become involved in more athletic events, this margin may narrow. Fracture location varies with chronologic age, a finding that is probably due to a combination of the anatomic maturation of the child and the age-specific activities of childhood. Several authors have shown that fractures are more common during the summer months when children are out of school. There is also a strong association between sunshine and fractures, and a negative association between rain and fractures. The afternoon is the most frequent time for fractures to occur, correlating with the time of peak activity for children. Injuries in the home during the late afternoon and evening account for more than 83% of all injuries to children. Moreover, the overall incidence of fractures occurring at home increases with the age of the child. In a Swedish study, fracture incidence was correlated with the degree of social disabilities such as welfare or alcoholism in the family.

Fractures are commonly found in children as a result of maltreatment. The incidence of physical abuse to children is estimated to be 4.9 per 1000. Of those abused, 1 of every 1000 will ultimately die as a result. Early recognition and reporting is essential because children who return home after hospitalization with unrecognized abuse have a 25% risk of serious future injury and a 5% risk of death. Children at highest risk for abuse are first-born children, premature infants, stepchildren, and handicapped children. Most cases of child abuse involve children younger than 3 years of age. Any young child presenting with an injury mechanism that does not fit the injury pattern, bruising or other associated injuries, or fractures in different stages of healing, should be viewed with circumspection as to cause ( Table 18.1 ). Diagnostic radiographic plain imaging with a skeletal survey is necessary for the child who is under the age of 2 years with an unexplained or suspicious fracture.

Pathophysiology

In the immature skeleton, longitudinal and appositional growth takes place through the physes (growth plates) located at the ends of the long bones, in the endplates of the vertebral bodies, or at the periphery of the round bones in the feet and hands. The physis is essential for normal skeletal growth, but it is also the weakest portion of the bone in children. Approximately 30% of fractures of the long bones include an injury to the physis. Most fractures that involve the growth plates heal without consequence. However, some injuries can result in permanent damage with significant sequelae such as angular deformity or complete cessation of growth.

The ends of every long bone consist of an epiphysis (near the joint), physis, and metaphysis (area of newly formed bone). At the time of skeletal maturity, the physis closes, which means there is no more longitudinal growth. Fracture healing in children is rapid and the potential for remodeling is great due to the growth potential of the immature skeleton. These characteristics allow for nonoperative treatment of some fractures in children that would receive operative treatment in the adult. Remodeling of fractures predictably occurs in the plane of primary motion of the adjacent joint (usually flexion/extension) and, to a lesser degree, in the coronal plane (varus and valgus deformities). Remodeling is not predictable in the transverse plane of fractures with rotational malalignment.

Physeal fractures are classified to predict outcome and guide treatment. Most orthopedic surgeons use the Salter Harris classification ( Fig. 18.1 ). Classic teaching states that type I and II injuries heal without growth abnormalities if reduced appropriately. However, some reports dispute some of this dogma. Types III and IV injuries usually occur in older children and frequently require anatomic realignment via open reduction to restore congruity of the joint to minimize the risk of arthritis and restore continuity of the physis to decrease the risk of growth disturbance. Type V injuries are higher energy crush injuries that are not usually recognized at the time of the injury but have a high risk of growth arrest.

Complex Injuries

Children sustain injuries that are different from those in adults due to their size and activities. A common example is a pedestrian struck by a car. An adult will frequently sustain an injury to the tibia or knee from the car’s bumper. However, the same mechanism will result in a fracture of the femur or pelvis in conjunction with a chest or head injury in a small child. Motor vehicle crashes (MVCs) are the most common cause of multiple injuries to children, both as occupants and pedestrians.

Open fractures are considered one of the true orthopedic emergencies in children. These injuries usually result from high-energy mechanisms and are often seen in the setting of multiple trauma. Open fractures in children and adults are classified according to the Gustilo–Anderson system ( Table 18.2 ). The four goals of treatment of open fractures are prevention of infection, bony union, prevention of malunion, and return to function of limb and patient. To attain these goals, the child’s tetanus status should be ascertained and open fractures treated by early irrigation and debridement along with broad-spectrum antibiotics. Kindsfater and Jonassen found that early treatment of tibial shaft fractures in children resulted in fewer cases of osteomyelitis when compared with those treated later. However, another study found no difference in infection or nonunion rates with delayed debridement in 390 open fractures of the lower extremities in adults. Additionally, in a study of 554 pediatric open fractures, there was no difference in infection rates when debridement was within 6 hours of injury as compared with 7–24 hours. There is no consensus on the effect of delayed operative treatment of open fractures in regard to rates of infection and need for secondary surgical procedures to promote bone healing. Our practice is to debride open fractures within 24 hours of presentation and more urgently if there is severe contamination or an injury in a high-risk environment such as a farm.

Table 18.2

Severity Classification for Open Fractures

From Gustilo RB, Mendoza RM, Williams DN. Problems in the management of type III (severe) open fractures: a new classification of type III open fractures. J Trauma 1984;24:747–796; Gustilo RB, Anderson T. Prevention of infection in the treatment of 1025 open fractures of long bones: retrospective and prospective analyses. J Bone Joint Surg Am 1976;50:453–458.

Grade	Description
I	Wound <1 cm
II	Transitional wound (1–10 cm)
III	Wound >10 cm
IIIA	Extensive soft tissue injury
IIIB	Reconstructive soft tissue injury
IIIC	Vascular injury

Pediatric traumatic amputations are unique injuries, typically caused by machinery, power lawnmowers ( Fig. 18.2 ), farm equipment ( Fig. 18.3 ), and MVCs. MVCs are the most common cause of an amputation in adolescents. Push and riding lawnmowers produce complex wounds with open fractures that resemble contaminated blast injuries with an annual incidence of approximately 11 per 100,000. These injuries frequently require serial debridement, internal or external fixation, and reconstruction of soft tissue defects. Wounds should not be surgically closed until the tissues are found to be clean. Unfortunately, amputation is often needed.