Proximal Radius Fractures in Children

Introduction

Pediatric fractures of the proximal radius account for 1% of all fractures in children and 4% to 10% of pediatric elbow injuries. These injuries are more likely to occur at the radial neck because of the biomechanically weaker physis in comparison to the fibrocartilaginous nature of the radial head. With increasing age and ossification of the physis, radial head injuries become more common in the pediatric and adolescent population. This chapter will focus on pediatric radial neck fractures, as treatment of radial head fractures in the older child and adolescent is analogous to that of the adult.

The incidence of proximal radius fractures is nearly equivalent between genders, with a potential slight predominance in girls. The average age range of pediatric radial neck fractures is 4–14 years, with the majority occurring between 9 and 12 years of age.

Pathoanatomy and Applied Anatomy Related to Mechanism of Injury

The pediatric elbow matures in a predictable manner with the appearance of secondary ossification centers occurring in a known sequence. Between 1 and 2 years of age, the capitellum is the first secondary ossification center to appear. Subsequently, the radial epiphysis appears between ages 2 and 4 years, the medial epicondyle appears between ages 4 and 6 years, the trochlea appears between 8 and 11 years of age, the olecranon between 9 and 11 years of age, and the lateral epicondyle between 10 and 11 years of age ( Table 30.1 ). Understanding the normal anatomic locations of these secondary ossification centers will aid in the interpretation of a pediatric elbow radiograph.

The mechanism of radial neck fractures typically involves a valgus-directed force onto an outstretched hand. In the pediatric population, this commonly occurs during a fall while running or during falls off monkey bars. As a valgus-directed force is applied, stress is transferred from the cartilaginous radial head abutting the lateral condyle of the humerus to the radial neck, resulting in a fracture and/or an elbow dislocation. Fractures of the proximal radius can also occur with concomitant posterior elbow dislocations or during reduction maneuvers performed to reduce the dislocated elbow. As the proximal radial epiphysis is posteriorly displaced, the capitellum can impact the proximal radius during reduction of the elbow, resulting in a fracture of the proximal radius.

Stress injuries can also occur when repeated rotational and longitudinal forces are exerted about the elbow. High-performance athletes who perform activities such as repetitive throwing and pitching motions can suffer from these injuries, which result in growth disruption and deformity. Furthermore, there are many associated injuries that can occur including medial epicondyle avulsion fractures, medial collateral ligament injuries, olecranon fractures, and elbow dislocations.

Fracture Classification

There are several classification systems used when describing pediatric and adolescent radial head and neck fractures. The Salter-Harris classification is most commonly used when describing fractures of the proximal radius involving the physis ( Box 30.1 ). Salter-Harris type II fractures are the most common type.

An alternative classification system has been proposed by O’Brien ( Box 30.2 ). This system uses the degree of angulation of the fracture for classification types and proposes treatment parameters dependent on the classification type.

Judet and colleagues proposed another classification system ( Box 30.3 ). This system has been utilized when assessing the feasibility of performing various treatment modalities. Type I and II Judet fractures are treated with closed reduction and casting, while type III and IV fractures require operative intervention.

The Wilkins classification, which combines the Jeffrey and Newman systems, describes the mechanism of injury and attempts to correlate it to the degree of injury and prognosis ( Box 30.4 ).

Lastly, the Bado classification is used to assess radial head and neck injuries associated with proximal ulna and/or olecranon fractures (Monteggia fracture/dislocations) ( Box 30.5 ). Additionally, Monteggia variants exist, which typically involve a fracture of the ulna shaft or olecranon with a concomitant radial neck fracture as opposed to a dislocation.

Assessment of Injury