Fractures and Dislocations in Children

General Principles

Fractures are common in children, occurring at a rate of 12 to 30 per 1000 children every year. The risk of sustaining a fracture between birth and 16 years of age has been reported to be 42% to 64% for boys and 27% to 40% for girls. Children and adolescents, because of their unique physiologic features, such as the presence of physes, increased elasticity of bone and other connective tissue structures, as well as decreased motor control and greater head-to-body weight ratio in younger children, have different patterns of fractures than adults. Although most fractures in children heal well without long-term complications, certain fractures, especially those involving the physis and articular surface, have the potential to cause significant morbidity.

Children, unlike adults, can remodel fractures as they grow, especially those in the plane of motion of the adjacent joint. Fractures that are angulated in the coronal plane have some remodeling potential, and those that are rotationally displaced have little to none. In the upper extremity, growth is more rapid at the proximal humerus and distal radius, whereas in the lower extremity it is primarily about the knee, at the distal femur and proximal tibia. Fractures that are closer to active physes, such as proximal humeral fractures, due to rapid growth have tremendous remodeling potential compared with fractures that occur in less active physes, such as radial neck fractures where less remodeling occurs. Understanding remodeling is essential in optimizing treatment for each patient. Because of these differences, a basic understanding of skeletal growth potential and maturation is essential in caring for children with fractures.

This chapter mainly discusses fractures that require operative management. Lateral condyle and femoral neck fractures have been called “fractures of necessity” because poor outcomes are certain without operative treatment. Some fractures, such as those of the proximal humerus, rarely require surgery. Nonunion in children is rare and if present is usually caused by factors such as open fracture, soft-tissue interposition at the fracture site, pathologic lesion, or vitamin D deficiency.

Growth Plate Injuries

It has been estimated that 30% of fractures in children involve a physis and most heal without any long-term complications. It is important to have knowledge of which fractures have a low potential for causing growth disturbance, such as those in the proximal humerus, and those that have greater potential, such as those in the distal femur and tibia. Histologically, most physeal fractures occur through the proliferative zone, which is the weakest region of the physis ( Fig. 36.1 ); however, they can occur through any zone. Some physeal fractures may be related to endocrinologic changes that occur around the time of puberty.

The most widely used scheme to classify these injuries is that of Salter and Harris, which is based on the radiographic appearance of the fracture as it relates to the physis as described below ( Fig. 36.2 ).

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    Type I fractures occur through the physis only, with or without displacement.

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    Type II fractures have a metaphyseal spike attached to the separated epiphysis (Thurston-Holland sign) with or without displacement.

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    Type III fractures occur through the physis and epiphysis into the joint with joint incongruity when the fracture is displaced.

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    Type IV fractures occur in the metaphysis and pass through the physis and epiphysis into the joint. Joint incongruity occurs with displaced fractures.

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    Type V fractures, which are usually diagnosed only in retrospect, are compression or crush fractures of the physis, producing permanent damage and growth arrest.

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    Type VI fractures are caused by a shearing injury to the peripheral aspect of the physis (perichondral ring). These fractures have been classically described in lawn mower accidents when the peripheral aspect of the physis is sheared off and have a high rate of angular deformity and growth arrest.

Although not completely prognostic, in general, Salter-Harris types III–VI fractures have a greater risk of complications than Salter-Harris types I and II injuries. An exception might be a completely displaced Salter-Harris type I fracture that has a greater potential for growth arrest than a nondisplaced Salter-Harris type IV fracture of the distal femur.

Although many Salter-Harris types I and II fractures can be treated nonoperatively, Salter-Harris types III and IV fractures usually require operative intervention, most commonly open reduction and internal fixation because of the intraarticular nature of the fracture and the potential for posttraumatic arthritis with nonanatomic reduction. Implants crossing the physis should be avoided when possible and when used should be smooth and the smallest diameter possible, and should be removed as soon as the fracture is stable ( Fig. 36.3 ). The treatment of specific fractures and the potential for growth arrest are discussed for each specific injury. Regardless of the injury type, parents need to be educated as to the possibility of growth disturbance and the need for long-term follow-up for any physeal fracture.

When growth arrest occurs, it can result in a shortening or angular deformity or both of the limb, depending on the size and the location of the growth arrest. Growth arrest most commonly results from a bony bar that crosses the physis. Although spontaneous correction of the bar with growth resumption has been reported, it is very rare. Central bars tend to lead to shortening, and peripheral bars tend to lead to angular deformity, but in most cases there are components of each. Certain fractures, such as distal femoral and distal tibial physeal fractures, have a higher rate of growth arrest and deformity than others. Once a bony bar occurs, the size and location of the bar can be determined using three-dimensional imaging such as computed tomography (CT) or volumetric magnetic resonance imaging (MRI). Physeal bar resection has been tried using a variety of direct and indirect methods, and the results have been unpredictable with unsuccessful outcomes occurring in 10% to 40% of patients. In general, younger patients with smaller (<30% of the physis) peripheral bars have a higher rate of success with bar resection than older patients with larger central bars. Bar resection is often combined with osteotomy to correct the resultant angular deformity as well. For large bars or those that are difficult to resect, epiphysiodesis of the remaining physis with staged angular correction and/or lengthening may be the best option.

When growth across the physis ceases symmetrically, such as with large central bars or with type V fractures, the primary problem is limb shortening. In the upper extremity, the major growth centers are the proximal humerus (arm) and distal radius and ulna (forearm). In contrast, the major growth centers in the lower extremity are the distal femur (thigh) and proximal tibia and fibula (leg) ( Fig. 36.4 ). Using either the Mosley straight-line graph or the Paley modifiers, the amount of deformity present at skeletal maturity can be predicted. The ultimate shortening that occurs is a result of the physis involved and amount of growth remaining. The relative contribution of each physis to overall limb segment growth is shown in Fig. 36.4 . Shortening is much better tolerated in the upper extremity than the lower extremity, and length equalization procedures are rarely used in the upper extremity. In general, patients with a lower extremity leg-length discrepancy at maturity of up to 2 cm can be treated with a shoe lift, those 2 to 5 cm with contralateral epiphysiodesis, and those greater than 5 cm with limb lengthening. With their improvements and increased use, intramedullary lengthening nails, which are extremely accurate, have a lower complication rate and better cosmetic result than traditional external fixation-based lengthening techniques, and these guidelines, especially those for epiphysiodesis, are being questioned.

Open Fractures

The general classification and principles associated with the treatment of open fractures apply to children as well. The most common open fractures in children are in the forearm and tibia followed by the hand, femur, and humerus. It is important to remember that factors such as thick active periosteum, greater periosteal bone formation potential, and lack of comorbidities lead to faster and more reliable bone healing in children than in adults. The initial management should consist of wound irrigation and debridement, antibiotics, and stabilization of the fracture. Treatment should be individualized for each patient. Timely administration of antibiotics has been shown to decrease infection rates in patients with open fractures. A multicenter study comparing irrigation and debridement of type I open forearm fractures in the emergency room compared to the operating room demonstrated no significant difference in overall infection rates, but length of stay and costs were decreased in the emergency room group. Larger studies are necessary, however, to determine if and which grade I open fractures can be treated in the emergency room because of the considerable variability in treatment methods among surgeons and the lack of quality evidence to guide treatment.

A large multicenter review of 536 children with 554 open fractures showed an overall infection rate of 3% with no difference in infection for all Gustilo and Anderson types comparing emergent (<6 hours) with delayed (>6 hours) surgical treatment. Grade III fractures in older children and adolescents have complication rates similar to those in adults. A recent meta-analysis showed no relationship between late debridement and increased infection rates in children with open fractures as well. The treatment of specific open fractures is discussed in this chapter.

Birth Fractures

Neonates who are diagnosed with a fracture in the first week of life without any evidence of trauma are considered to have a birth fracture. The incidence is approximately 0.1/1000 live births and may be related to forced obstetric maneuvers. The most commonly fractured bones include the humerus, clavicle, and femoral shaft. Risk factors include very large or very small fetuses, breech presentation, instrumented delivery, small uterine incision (cesarean section), twin pregnancy, prematurity and prematurity-related osteopenia, and osteogenesis imperfecta. Between 60% and 80% of patients do not have positive findings on the initial newborn examination. Prenatal ultrasound may help to identify high-risk patients, such as those with osteogenesis imperfecta before delivery.

Clinically, patients present with warmth, swelling, pain, and irritability with motion. Some children present with pseudoparalysis or failure to move a limb, which can be confused with differential diagnoses of osteomyelitis, septic arthritis, or brachial plexus palsy. Because it may take several days for some of these signs to develop, delayed diagnosis of 1 to 2 days is common. Most birth fractures do not require operative treatment, heal quickly, and remodel fully. Clavicular or humeral shaft fractures can be treated by pinning the baby’s sleeve to the front of the shirt for 1 to 2 weeks until healed. Femoral shaft fractures can be treated with splinting or a Pavlik harness. Spica casting rarely is necessary. Physeal separations, especially at the distal femur and distal humerus, are rare but can occur with difficult delivery. Advanced imaging such as arthrography or ultrasound can be used to make the diagnosis. (These specific injuries are discussed later in the chapter.)

Nonaccidental Trauma

Musculoskeletal injuries are the second most common type of injury after soft-tissue injury, occurring 10% to 70% of the time in children with nonaccidental trauma (NAT). Because of this, 30% to 50% of these children are seen by an orthopaedic surgeon. Because there is no specific test to make the diagnosis of NAT, a careful history and physical examination must be performed and appropriate use of imaging is necessary. This usually is done using a multidisciplinary team approach. Having a high index of suspicion of NAT is essential because in up to 20% of children with NAT the diagnosis is missed on their initial medical visit. Making the diagnosis is essential because there is a high rate of reabuse and even death in children when the diagnosis is missed. It is important to be aware of risk factors for NAT and of certain injuries that are highly suggestive of this mechanism of injury. Risk factors for NAT include age younger than 2 years, children with multiple medical problems, fractures or injuries in different stages of healing, posterior rib fractures, and long bone fractures in young patients ( Fig. 36.5 ). Other social factors, such as parental unemployment or drug abuse, lower socioeconomic status, and single parent households, have been shown to correlate with a higher risk of NAT as well. Common fractures in abused children are in the humerus, tibia, and femur. Radiographic features such as soft-tissue swelling (1 to 2 days), periosteal reaction (15 to 35 days), soft or hard callus (36 days), and bridging and remodeling (after 45 days) can be used to determine the age of the fracture. Other conditions in the differential diagnosis of NAT include metabolic bone disease and genetic conditions that can lead to bone fragility, such as osteogenesis imperfecta, rickets, renal disease, disuse osteopenia, and the use of certain medications such as corticosteroids.

Humeral shaft fractures in children younger than 3 years were at one time thought to be associated with NAT, but most are not. However, a high index of suspicion must remain for NAT in any child younger than 1 year of age with a long bone fracture. Humeral shaft fractures, although less often than clavicular fractures, can occur at birth. Risk factors include large babies, shoulder dystocia, and the use of assistive devices. These children often present with pseudoparalysis that can be confused with a brachial plexus palsy and septic arthritis.

When NAT is suspected, a skeletal survey ( Box 36.1 ) should be ordered in children up to the age of 3 years according to the American Academy of Orthopaedic Surgery 2009 Clinical Practice Guidelines, especially when the child is younger than 1 year of age, when there is no history or an inconsistent history of injury, or in those in whom the fracture is attributed to NAT or domestic violence to look for secondary injuries. Patients with buckle fractures of the distal radius and toddlers with a fracture of the tibia do not need routine skeletal survey. It should be noted that lower extremity long bone fractures in ambulatory children rarely are caused by NAT. On skeletal survey, 50% of children have one fracture, 21% have two, 12% have three, and 17% have more than three. Controversy exists as to which studies are optimal to include in a skeletal survey; however, rib films are essential because of the high sensitivity and specificity for NAT. Because imaging around active physes is difficult, and with improvements in plain radiographic techniques, bone scan rarely is used in the evaluation of NAT.

Certain fracture types such as spiral femoral fractures and metaphyseal corner fractures were thought to be pathognomonic for NAT. Recent studies have shown that spiral femoral fractures actually are rare in abused children and that transverse fractures are more predictive of NAT. A recent review has shown that the metaphyseal corner fracture, once thought to be pathognomonic for NAT, is very similar to fractures seen with rickets. It is important to remember that fracture morphology gives information about the direction but not the etiology of the force applied and that the presence or absence of a fracture is probably more important than its morphology.

Clavicle

Fractures of the clavicle are common in children and adolescents, with a peak age for clavicular fractures being 10 to 19 years of age. Most fractures heal well with nonoperative treatment, especially in young children. Although there has been a dramatic increase in the operative treatment of clavicular fractures in all age groups, the role of operative treatment of clavicular shaft fractures in children and adolescents remains controversial. A review of members of the Pediatric Orthopaedic Society of North America showed that the majority preferred nonoperative treatment for all fracture patterns; however, older age (16 to 19 years), evidence in the adult literature, and physician years of experience (<5 years) predicted operative treatment preference. Excellent clinical and radiographic outcomes have been reported for both nonoperative and operative management of these injuries. Operatively treated patients typically have a faster return to activities but also have a higher complication rate in terms of symptomatic implants and nonunion. A recent study showed the overall complication rate following surgical treatment of 37 fractures in 36 pediatric patients to be 86%, with painful implants being the most common complication (59%), and a major complication rate of 43%, including nonunion and refracture around the plate and/or screw holes following plate removal. The rate of malunion is higher and almost exclusively associated with nonoperative treatment; however, patients with established malunions have excellent functional outcome scores. Although studies have shown good outcomes with both methods of treatment, stronger evidence is needed to determine if one method is superior to the other. The indications for operative treatment are open fracture, polytrauma, floating shoulder, fractures with skin compromise or neurovascular injury, and widely displaced or shortened fractures in older adolescents. Operative treatment of these injuries is described in Chapter 57 .

Sternoclavicular Fractures and Dislocations

The medial clavicle is one of the last growth centers to ossify, typically around 25 years of age. Fractures of the medial clavicle are usually Salter-Harris type I or II fractures, which in most cases heal with closed management and without complications ( Fig. 36.6 ). It can be difficult to differentiate these injuries from true sternoclavicular joint dislocations because clinically they appear similar. The use of CT scan is helpful in these situations not only to determine the fracture pattern but also to evaluate the relationship between the fracture fragments and the mediastinal structures such as the brachiocephalic vein, which is the most commonly compressed structure, and innominate artery with posteriorly displaced fracture dislocation. Although injuries to the great vessels or mediastinal structures are often cited as complications of posterior sternoclavicular dislocations, a recent multicenter study of 125 such dislocations found no vascular or mediastinal injuries during reduction or fixation that required intervention. Anteriorly displaced fractures usually heal with a “bump” over the proximal clavicle but rarely are symptomatic. Up to 50% of patients with posteriorly displaced fractures may remain symptomatic. This, along with the higher complication rate in repair of longstanding sternoclavicular dislocation, leads most authors to recommend operative treatment of these acute injuries. Closed reduction under anesthesia can be attempted, but there is a high redislocation rate. Because the epiphyseal (proximal) fragment is small, fixation is usually achieved with FiberWire (Arthrex Inc., Naples, FL) or suture repair. Care must be taken to protect the adjacent neurovascular structures and pleura. A recent meta-analysis showed that although considerable variability in the literature exists, good results can be obtained with both open and closed treatment as long as a stable reduction is achieved. It also showed that early treatment is better because patients treated less than 48 hours after injury had better results than those treated later. Patients who undergo late operative treatment for chronic posterior fracture-dislocation have been shown to do well with activities of daily living but have pain when returning to the same level of athletic participation.

Lateral (Distal) Clavicular Fractures

Injuries to the distal clavicle in young children are rare. In older children and adolescents these injuries appear very similar to acromioclavicular joint injuries. These injuries are really physeal fractures in which the epiphysis and physis maintain their normal anatomic relation to the shoulder joint, whereas the distal metaphysis is displaced superiorly, away from the underlying structures. The periosteal sleeve generally is intact inferiorly, and the ligamentous structures connecting the clavicle to the coracoid usually remain attached to the periosteal sleeve ( Fig. 36.7 ). Because the periosteal sleeve is highly osteogenic, these fractures have a tremendous potential to remodel, and most patients do well with nonoperative treatment. Operative treatment, consisting of open reduction and internal fixation, usually is reserved for adolescent patients with significant displacement and limited remodeling potential. The operative treatment of lateral clavicular injuries is discussed in Chapter 57 .

Acromioclavicular Dislocations

There are five types of acromioclavicular injuries described in children ( Fig. 36.8 ). Type I injury is not sufficient to completely rupture the acromioclavicular or the coracoclavicular ligaments. Type II injury damages the acromioclavicular ligaments but not the coracoclavicular ligaments; a partial periosteal sleeve (tube) tear also occurs. In type III injury the acromioclavicular ligament is completely ruptured, but the coracoclavicular ligaments are intact because they are still attached to the periosteum. The clavicle is unstable and is displaced superiorly through a rent in the periosteal sleeve (pseudodislocation). Type IV injury is identical to type III except that, in addition to being displaced superiorly, the clavicle is displaced posteriorly. Type V injury is severe; the acromioclavicular ligaments are disrupted, and, although the coracoclavicular ligaments are still attached to the periosteal sleeve, the clavicle is now unstable and its lateral end is buried in the trapezius and deltoid muscles or has pierced them and is located under the skin in the posterior aspect of the shoulder.

In many type III, IV, and V dislocations, an unrecognized fracture of the distal end of the clavicle occurs, with the acromioclavicular and coracoclavicular ligaments remaining intact and attached to the empty periosteal tube or to the most distal fragment. In children and adolescents up to age 15 years, types I, II, and III acromioclavicular separations, even with fracture of the distal third of the clavicle, can be treated by nonoperative means. In patients older than age 15 years, type III injuries may require surgery. Open reduction and internal fixation should be considered for markedly displaced types IV and V fractures (see Chapter 57 ).

In types IV and V acromioclavicular dislocations, it is important to disengage the distal clavicle from the trapezius and deltoid muscles. If this is unsuccessful by closed means, surgery is indicated to remove the clavicle from the muscles and replace it in the periosteal tube. The periosteal tube should be repaired, and the deltoid-trapezius muscle fascia should be imbricated superiorly over the clavicle. If the repair is unstable, internal fixation is required, as in adults, by acromioclavicular or coracoclavicular fixation, as described in Chapter 57 .

Shoulder Dislocations

Shoulder dislocations in children are rare, and proximal humeral physeal fractures are much more common. In a review of 500 glenohumeral dislocations, only eight patients were younger than 10 years of age (1.6%). Another study of 1937 patients aged 10 to 16 years who had closed reduction of a glenohumeral dislocation found that children ages 10 to 12 years composed only 6% of the cohort and had a significantly lower rate of redislocation than older children. It is thought that glenohumeral dislocations in skeletally immature patients may become more common as the level of sports participation increases. A series of 14 skeletally immature patients treated with closed reduction found a redislocation rate of 21% at a mean of 5 years’ follow-up. Glenohumeral dislocation has been reported when associated with a proximal humeral metaphyseal fracture. The natural history, diagnosis, and management of shoulder dislocations for adolescents is similar to adults, as described in Chapter 60 .

Proximal Humeral Fractures

Proximal humeral fractures are relatively rare in the pediatric population, accounting for 0.5% of pediatric fractures and 4% to 7% of all epiphyseal fractures. Of the physeal fractures, the majority are Salter-Harris type II fractures and Salter-Harris types III and IV are rare. They are most often classified by the Neer-Horowitz classification as shown in Box 36.2 . A systematic review of the treatment of proximal humeral fractures in children found that nonunions did not occur and malunions were exceedingly rare, regardless of the method of treatment. This is due to the rapid growth and remodeling potential of the proximal humerus, especially in young children. In children younger than 10 years, it has been shown that angulation of up to 60 degrees can remodel completely, whereas in older children and adolescents it is closer to 20 to 30 degrees. A recent cohort-matched comparison of operative and nonoperative treatment of 32 proximal humeral fractures showed no difference in complications, functional outcome, or patient satisfaction. Within the nonoperatively treated group, there was a higher rate of dissatisfaction in patients older than 12 years treated nonoperatively. They found the odds ratio of an undesirable outcome increased 3.81 for each year of age with nonoperative treatment.

Operative Treatment

Operative treatment usually is reserved for older children and adolescents because of the excellent outcomes with nonoperative treatment seen in children younger than 10 years of age. If attempted closed reduction fails, open reduction is indicated. Other indications for open reduction using the deltopectoral approach include open fracture and skeletal maturity (or close to skeletal maturity) ( Fig. 36.9A,B ) . The most common impediments to obtaining a successful closed reduction include the periosteum, biceps tendon, deltoid muscle, and comminuted bone fragments. Once a satisfactory reduction has been achieved, the fracture can be stabilized with Kirschner wires, cannulated screw(s), or flexible titanium elastic intramedullary nails (TEIN), all of which have been shown to have good outcomes. The use of a cannulated screw or screws, which has been shown to be biomechanically stronger than multiple Kirschner wire fixation, has increased because of the soft-tissue irritation and need for a return to the operating room for Kirschner wire removal. The use of TEIN has been shown to produce good radiographic and functional results in several studies; however, implant removal is occasionally necessary because of prominence. A comparison of percutaneous pinning and TEIN found that both techniques are effective in fracture stabilization in older children. The use of TEIN was shown to have a lower complication rate than percutaneous pinning; however, TEIN use was associated with increased blood loss, operative time, rate of reoperation for hardware removal, and cost.

Humeral Shaft Fractures

Humeral shaft fractures in children are uncommon, accounting for less than 10% of all humeral fractures in children. Most occur either in children younger than 3 years or older than 12 years, and almost all of these injuries can be treated nonoperatively because of the remodeling potential of the humerus and the ability of the glenohumeral joint to accommodate for any residual malalignment. Up to 70 degrees of angulation in children younger than 5 years and 30 degrees of angulation in children ages 12 to 13 can be accepted. Less angulation in distal fractures, especially those in varus, is acceptable because of the undesirable cosmetic appearance of the arm. Closed treatment usually consists of coaptation splinting, fracture bracing, or the use of a hanging arm cast. Operative treatment, consisting of plating or the use of TEIN, has been shown to provide good results. External fixation can be used in rare conditions in which severe soft-tissue injuries are present. Indications for operative treatment include patients with polytrauma to speed mobilization and upper extremity weight bearing, a floating elbow, a pathologic lesion, and adolescents close to skeletal maturity. Radial nerve entrapment can occur, especially with distal fractures after closed reduction maneuvers. A loss of radial nerve function after closed reduction indicates potential entrapment of the nerve between the fracture fragments, and urgent nerve exploration and internal fixation are necessary. Plating techniques for children are similar to adults as discussed in Chapter 57 .

Supracondylar Humeral Fractures

A review of over 63,000 supracondylar humeral fractures in the United States over a 5-year period showed the rate of injury to be 60 to 70 per 100,000 children. The mean age of patients with closed fractures was 5.5 years (52% male), with 54% of them occurring in children 4 to 6 years of age. Older patients (mean age, 9.1 years) were more likely to sustain open fractures and neurologic injuries. Almost all (98%) are extension-type injuries, which usually are caused by a fall onto an outstretched hand. Flexion-type fractures, although rarer, are more difficult to reduce, have worse outcomes, and are associated with ulnar nerve injury ( Fig. 36.10 ). Approximately 5% to 10% of children have an associated ipsilateral distal radial fracture. The most commonly used classification is that by Gartland in which type I fractures are nondisplaced, type II fractures have an intact posterior hinge, and type III fractures have complete displacement. A type IV injury has been described in which there is complete loss of the anterior and posterior periosteal hinge, making it unstable in both flexion and extension. Type IV fractures usually are the result of high-energy injury. Care must be taken when reducing a type III fracture to avoid tearing the periosteal hinge, making it a type IV injury. The diagnosis can be made in most cases using plain radiographs. Advanced imaging, such as CT, occasionally is used in an adolescent when there are concerns about a coronal split in the distal fragment or T-condylar fracture.

A careful neurologic examination is essential because 10% to 15% of patients have a nerve injury, with the anterior interosseous nerve being the most frequently injured in extension-type fractures. The ulnar nerve is most frequently injured in flexion-type injuries in 10% of patients. Obese children have been shown to have a higher rate of both preoperative and postoperative nerve palsy and higher rate of open reduction. A loss of neurologic function after reduction is concerning for nerve entrapment at the time of reduction, and urgent open exploration of the nerve is necessary. Most nerve injuries are a result of neurapraxia and resolve within 6 to 12 weeks; electromyography is indicated if there is no return of nerve function within 3 months. A recent long-term follow-up study of patients with neurologic injuries showed that at an average follow-up of 8 years most patients had excellent function; 100% of patients with radial nerve, 88% of patients with median nerve, and only 25% of patients with ulnar nerve injuries fully recovered.

Urgent assessment of the vascular status of the limb also is essential to minimize complications. A vascular injury, typically to the brachial artery, can occur in up to 10% to 20% of patients with a type III fracture ( Fig. 36.11 ). Because of the rich collateral blood supply about the elbow, the hand may be well perfused even with complete disruption of the brachial artery. The vascular status of the limb can be classified as normal—pulseless but with a warm pink (perfused) hand—or pulseless, pale (nonperfused) hand. Treatment of patients with a pulseless warm hand remains controversial in terms of the need for brachial artery exploration ( Fig. 36.12 ). A supracondylar fracture with a nonperfused hand is a surgical emergency to prevent reperfusion injury and compartment syndrome leading to Volkmann ischemic contracture. Compartment syndrome occurs in approximately 0.1% to 0.3% of patients with supracondylar humeral fractures and is more common with concurrent fracture of the forearm or wrist. In pediatric patients, the 3 A’s— a gitation, a nxiety, and increasing a nalgesia requirements—are sensitive and reliable indicators of impending compartment syndrome.

In patients with vascular compromise, urgent reduction in the operating room should be performed and the vascular status of the hand assessed. Arteriography should not be used unless the level of vascular injury is unclear in patients with polytrauma and should never delay closed reduction of a supracondylar humeral fracture. If perfusion is not restored, urgent exploration of the brachial artery with release of entrapping structures and direct repair with vein grafting if necessary should be performed by a surgeon with experience in the repair of small vessels. Prophylactic forearm and hand fasciotomies are necessary in patients with prolonged ischemia time. This is especially important in patients with concomitant nerve injuries in which the ability to detect a compartment syndrome clinically is impaired. Most patients in whom perfusion is restored (pink hand) even in the absence of a radial pulse have good long-term outcomes with observation.

Treatment of supracondylar humeral fractures is based on the Gartland type. Type I fractures are treated with long arm cast immobilization for 3 weeks followed by a brief period of protected activity. Patients with the presence of a posterior fat pad on radiographs should be presumed to have a type I fracture and treated in this fashion.

Treatment of type II injuries is somewhat controversial. Wilkins subdivided type II injuries into A and B with type IIA fractures being stable and type IIB fractures having some degree of rotation or translation making them unstable. Closed reduction and casting can be used in patients with type IIA injuries. Closed reduction and percutaneous pinning typically with two or three lateral pins has become the main form of treatment for type IIB injuries and for those in which the stability is in question. Pinning is preferred for most type II fractures because of concerns about the ability to maintain reduction in a splint or cast, poor patient compliance with barriers to timely follow-up, and difficulty in differentiating between type IIA and B fractures. Type III and IV fractures are treated with closed reduction and pinning ( Fig. 36.13 ).

Complications of percutaneous pinning occur in approximately 5% of patients, with pin migration or irritation being the most common followed by infection (1%) and elbow stiffness. The ideal pin configuration remains controversial; however, although crossed medial and lateral pins are more stable than two lateral pins in vitro, use of two or three lateral pins appears to be equal to crossed pins in vivo. A comparison study of medial crossed pins and lateral entry pins showed equal maintenance of reduction in both groups, but the crossed pin group had a 7.7% rate of iatrogenic nerve injury. This rate of iatrogenic nerve injury with crossed pins has been shown in other studies as well. If lateral pinning is used, it is important to engage both fragments and have bicortical fixation with at least two pins and at least 2 mm of pin separation at the fracture site. Most centers use two or three lateral pins for most type III fractures and use a medial pin for fractures that are very unstable ( Figs. 36.14 and 36.15 ). If a medial pin is used, making a small incision and using retractors to protect the ulnar nerve, as well as avoiding pinning these fractures in maximal elbow flexion, can reduce the rate of ulnar nerve injury. It is difficult to maintain reduction of type IV fractures because of the loss of the periosteal hinges. For this reason, it may be necessary to hold the arm stable and rotate the C-arm for imaging rather than rotating the arm. A transolecranon pin placed retrograde from the proximal ulna into the humeral shaft can be used to provisionally control these highly unstable fractures during pinning ( Fig. 36.16A,B ) . The indications for open reduction, which occurs approximately 10% of the time, include irreducible fractures, open fractures, and those with suspected or confirmed neurovascular injuries. A direct anterior approach can be used in most patients with posterior displaced fracture because it provides the best access to the neurovascular structures and fracture site. Because of the muscle stripping that occurs with these injuries, the neurovascular structures are typically in a subcutaneous position ( Fig. 36.17 ).

Lateral Condylar Fractures

Fracture of the lateral condyle is the second most common (17%) pediatric elbow fracture after fracture of the supracondylar humerus, usually occurring between the ages of 4 and 6 years. The most common mechanism of injury is a fall onto an outstretched arm with the elbow in varus, which causes avulsion of the lateral humeral condyle. Alternatively, these injuries can occur, although less commonly, during a fall onto a flexed elbow. Unlike supracondylar humeral fractures, lateral condylar fractures are rarely associated with neurovascular injuries.

These injuries can be classified either anatomically or by displacement. Historically, the Milch classification was used to determine whether the fracture passed through (type I) or around (type II) the capitellum. The Milch type II fracture, which is really a Salter-Harris type II fracture, is the most common type (95%) ( Fig. 36.24 ). More often the fractures are classified by displacement because the amount of displacement determines the method of treatment. A recent displacement-based classification system by Weiss et al. has been shown to be prognostic for complications. Type I fractures are displaced less than 2 mm, type II fractures are displaced more than 2 mm with an intact cartilaginous hinge, and type III fractures are displaced more than 2 mm without an intact cartilaginous hinge ( Fig. 36.25 ). Type III fractures tend to be displaced and rotated and, in some cases, if enough trochlear stability is lost, a posterolateral subluxation of the radius and ulna can occur ( Fig. 36.26 ). This classification also helps guide treatment, because type I fractures can be treated with a cast, type II fractures with percutaneous pinning, and type III fractures with open reduction and internal fixation.

Radiographically, it can be difficult to determine the amount of displacement because of the large amount of unossified epiphysis present. The presence of a metaphyseal fragment on the lateral radiograph is helpful in making the diagnosis ( Fig. 36.27 ). The addition of an internal oblique radiograph is necessary to assess the true amount of displacement. It can be difficult to determine the stability of the cartilaginous hinge on plain radiographs, and it may be necessary to perform stress radiographs or arthrography under anesthesia for full assessment. Advanced imaging such as MRI can be used when the diagnosis is in question or to evaluate the stability of the cartilaginous hinge; however, this may require sedation to obtain satisfactory high-resolution images in this age group.

Nondisplaced or minimally displaced fractures can be treated in a long arm cast for 4 to 6 weeks depending on the age of the patient. These fractures need to be watched closely because late displacement can occur in 5% to 10% of fractures. For type II fractures or fractures in which there is concern about the integrity of the cartilaginous hinge, a stress examination under anesthesia with or without arthrography may be performed. In patients with a large metaphyseal fragment, percutaneous pinning using smooth Kirschner wires or a cannulated screw is performed. Displaced fractures or those with unclear reduction require open reduction and internal fixation ( Fig. 36.28 ). This is done most commonly through a lateral approach, taking care to avoid dissection posteriorly that may injure the blood supply to the trochlea, which enters posteriorly, and cause osteonecrosis. Alternatively, in rare cases when a lateral approach is not possible, a posterior approach protecting the posterior blood supply has been described. Fixation using smooth Kirschner wires and cannulated screws has been described with good results. The use of cannulated screws is becoming more common as they allow for fracture-site compression, leading to faster time to union and earlier mobilization and avoiding the risk of pin site infections with Kirschner wires. If Kirschner wires are used, typically in younger patients, they can safely be left outside the skin for 3 to 4 weeks to avoid a second surgical procedure to remove buried wires.

The most common complication after fracture of the lateral condyle is loss of reduction. Therefore close follow-up is necessary for these patients. Even fractures with less than 2 mm of initial displacement can displace late.

Medial Condylar Fractures

Fractures of the medial humeral condyle in children are rare, accounting for 1% of pediatric elbow fractures. They usually occur in slightly older children than fractures of the lateral condyle, around the ages of 3 to 8 years. They are caused by a direct fall onto the elbow or a fall onto an outstretched hand with the elbow in a varus position. Medial condylar fractures in younger children can be associated with nonaccidental trauma. Kilfoyle described three types based on displacement: type I, a greenstick or impacted fracture; type II, a fracture through the humeral condyle into the joint with little or no displacement ( Fig. 36.36 ); and type III, an epiphyseal fracture that is intraarticular and involves the medial condyle with the fragment displaced and rotated ( Fig. 36.37 ). Type III fractures, which occur in older children, account for 25% of all medial condylar fractures. In type III fractures the flexor pronator mass, which is attached to the distal fragment, causes the distal fragment to rotate anteriorly and medially, causing the articular surface to face posteriorly and laterally ( Fig. 36.38 ). This injury often is confused with medial epicondylar fracture, which is more common but occurs in older children. Making a radiographic diagnosis can be difficult, especially in younger patients in whom the trochlea has not yet ossified, which occurs around the age of 8 years. MRI and elbow arthrography can be used to make the diagnosis in unclear cases. Medial epicondylar fractures often occur with elbow dislocations and, because of the intraarticular nature of the medial condyle, patients with medial condylar fractures, unlike those with medial epicondylar fractures, have fat pad changes evident on radiographs.

For nondisplaced fractures treatment consists of 4 to 6 weeks of cast immobilization. These fractures heal more slowly than supracondylar fractures and are more like lateral condylar fractures because of the intraarticular nature of the fracture site. The treatment for displaced fractures is open reduction and internal fixation to ensure joint congruity. This is best done through a posteromedial incision, which provides excellent exposure of the fracture site and allows for protection of the ulnar nerve. Care must be taken not to extend the dissection posteriorly to avoid injury to the trochlear blood supply. Fixation consists typically of two smooth Kirschner wires in younger children and screw fixation in older children to control rotation and prevent nonunion that can occur with inadequate fracture fixation (see Fig. 36.38 ).

Medial Epicondylar Fractures

Medial epicondylar fractures account for approximately 10% of pediatric elbow fractures, with a peak age at occurrence of 11 to 12 years. Between 30% and 50% occur with elbow dislocations, and it is important to ensure that the medial epicondyle is not entrapped after reduction of the dislocation.

The most common mechanism of injury is an avulsion that can occur as a result of a valgus stress being placed on the extended elbow, usually after a fall. The medial epicondylar apophysis is the origin of the ulnar collateral ligament, which, if under valgus stress, avulses it. It can also occur as a result of a pure avulsion by the forearm flexors and rarely with a direct blow to the elbow. In complete fractures, the avulsed apophysis displaces distally from pull of the forearm flexor mass originating on it. Standard radiographic studies have shown that accurately measuring the true amount of displacement in all planes is difficult compared to CT scanning. A newer radiographic view, the distal humerus axis (axial) view, has been shown to be more accurate and reliable while reducing the need for advanced imaging ( Fig. 36.39 ).

Nondisplaced fractures can be treated with 2 to 3 weeks of immobilization in a long arm cast or brace followed by gradual resumption of activity. The absolute indication for operative treatment is an entrapped intraarticular apophyseal fragment in an elbow dislocation, which can be performed urgently and not emergently unless ulnar nerve injury is present. Other indications include fractures associated with elbow dislocations to allow early range of motion and fractures displaced more than 1 cm. A relative indication is a minimally displaced fracture in a high-demand throwing athlete. Treatment of mildly displaced fractures, less than 1 cm, remains controversial because of the difficulty in measuring true displacement, the good results being reported in small series of patients treated both operatively and nonoperatively, and the lack of comparison studies.

Surgery can be performed with the patient supine or prone in the “hammerlock position,” which provides relaxation to the forearm flexor musculature, making reduction easier ( Fig. 36.40 ). Careful dissection is necessary if the epicondyle is entrapped to prevent injury to the ulnar nerve ( Fig. 36.41 ). Typically a single 4.0- or 4.5-mm cannulated screw is used for fixation, and a long arm cast is worn for 2 to 3 weeks before beginning physical therapy. In comminuted fractures, which are rare, smooth Kirschner wires, suture anchors, or both can be used to stabilize the fragments. Patients are treated with a long arm cast or brace for 2 to 3 weeks followed by physical therapy.

Distal Humeral Fractures

Fracture of the entire distal humeral physis, which occurs more distally than a supracondylar fracture ( Fig. 36.42 ), most commonly occurs during a fall and most frequently in young children (mean age, 5 years). This injury has historically been underreported because making the diagnosis was difficult. With increased awareness and advanced imaging techniques such as MRI, ultrasound, and arthrography, this injury is being diagnosed with greater frequency.

The distal humeral epiphysis extends across to include the secondary ossification of the medial epicondyle until about 6 to 7 years of age in girls and 8 to 9 years in boys. Most fractures involving the entire distal humeral physis occur before the age of 6 or 7 and usually younger. The younger the child, the greater the volume of distal humerus occupied by cartilaginous epiphysis. As children mature, the volume of the epiphysis decreases, which some authors believe is protective of injury. This may explain the association between distal humeral physeal fractures and birth trauma, as well as NAT. In addition, the physeal line in infants is near the center of the olecranon fossa, making it prone to hyperextension injury. Malunion after these injuries is less common because of the broad surface area of the distal humerus. Because the blood supply to the medial trochlea courses through the physis, osteonecrosis of the trochlea can occur.

These fractures are classified into three groups based on the degree of ossification of the lateral condylar epiphysis. Group A fractures occur in infants up to 12 months of age, before the secondary ossification center of the lateral condylar epiphysis appears (and are usually Salter-Harris type I physeal injuries) ( Fig. 36.43 ). These often are missed because the lateral condylar epiphysis lacks an ossification center. Group B fractures occur most often in children 12 months to 3 years of age in whom there is definite ossification of the lateral condyle. Group C fractures occur in older children, from 3 to 7 years of age, and result in a large metaphyseal fragment.

In an infant younger than 18 months of age whose elbow is swollen secondary to trauma or suspected trauma, a fracture involving the entire distal humeral physis should be considered. In a young infant or newborn, swelling may be minimal with little crepitus because the fracture fragments are covered in cartilage (physis) rather than bone.

Radiographic diagnosis can be difficult, especially if the ossification center of the lateral condyle is not visible. The only relationship that can be determined is that of the primary ossification centers of the distal humerus to the proximal radius and ulna ( Fig. 36.44 ). The proximal radius and ulna maintain an anatomic relationship to each other but are displaced posteriorly and medially in relation to the distal humerus. Comparison views of the opposite uninjured elbow may be helpful to determine the presence of displacement.

Once the lateral condylar epiphysis becomes ossified, displacement of the entire distal epiphysis is much more obvious. The anatomic relationship of the lateral condylar epiphysis with the radial head is maintained, even though the distal humeral epiphysis is displaced posterior and medial in relation to the metaphysis of the humerus.

Because they have a large metaphyseal fragment, type C fractures may be confused with either a low supracondylar fracture or a fracture of the lateral condylar physis. The key diagnostic point is the smooth outline of the distal metaphysis in fractures involving the total distal physis. With supracondylar fractures, the distal portion of the distal fragment has a more irregular border.

A lateral condylar physeal fracture in an infant can be differentiated from the rare elbow dislocation by radiograph. With a displaced fracture of the lateral condylar physis, the relationship between the lateral condylar epiphysis and the proximal radius usually is disrupted. If the lateral crista of the trochlea is involved, the proximal radius and ulna may be displaced posterolaterally. Elbow dislocations are rare in the peak age group for fractures of the entire distal humeral physis. With elbow dislocations, the displacement of the proximal radius and ulna is almost always posterolateral, and the relationship between the proximal radius and lateral condylar epiphysis is disrupted. Comparison views are helpful in making this diagnosis. Ultrasound can also be used to make the diagnosis and avoid the use of general anesthesia in infants.

Treatment

Treatment is first directed toward prompt recognition. Because this injury may be associated with child abuse, the parents may delay seeking treatment and ossification may already be present on the initial radiographs. These injuries, when recognized in a timely fashion, can be treated with closed reduction and percutaneous pinning ( Fig. 36.45 ). Arthrography can be helpful to define the cartilaginous distal fragment ( Fig. 36.46 ). Missed untreated fractures may remodel completely without any residual deformity if the distal fragment is only medially translocated and not tilted. In older children, these injuries can be stabilized with either percutaneous pinning or TEIN. The more proximal the fracture and the closer to the metaphyseal-diaphyseal junction, the more difficult and less biomechanically stable percutaneous pinning becomes, making TEIN the better option.

Capitellar Fractures

Fractures of the capitellum, which make up less than 1% of pediatric elbow fractures, involve only the true articular surface of the lateral condyle, including in some instances the articular surface of the lateral crista of the trochlea. Unlike in adults, these fractures are rare in children and usually occur in adolescents. Murthy et al. classified capitellar fractures into three types: type I are anterior shear fractures and are the most common, type II are posterior shear fractures, and type III are chondral shear fractures ( Fig. 36.47 ). The diagnosis can often be made using plain radiographs; MRI can be helpful, especially when the fragment is primarily cartilaginous, and in types II and III injuries, which often are missed on plain radiographs ( Fig. 36.48 ).

Excision of the fragment, if small, and open reduction and reattachment are the two most common forms of treatment. However, because of the intraarticular nature of the injury, closed reduction is not likely to be successful. Many small fragments can be excised through either a lateral open or arthroscopic approach. This eliminates the need for postoperative immobilization and accompanying elbow stiffness. Open reduction and internal fixation can be performed if the fragments are large enough; however, osteonecrosis of the attached fragment can occur. Compression screws have been shown to provide stable fixation ( Fig. 36.49 ). Alternatively, a suture repair can be performed if the fragment is primarily cartilaginous, which allows for follow-up MRI examination and eliminates the need for implant removal ( Fig. 36.50 ). Regardless of the treatment method used, patients and parents should be counseled that elbow motion will be lost after this injury, especially in patients with large osteochondral fragments that involve the trochlea, and that up to 40% of patients require a secondary procedure because of stiffness, painful or prominent implants, and osteonecrosis.

Olecranon Fractures

Isolated physeal fracture of the olecranon in children is uncommon due in part to the broad-based insertion of the triceps. When it does occur, it typically is the result of an avulsion force being applied to the olecranon with the elbow flexed. Although rare in the general population, these fractures, especially bilateral ones, are well described in children with osteogenesis imperfecta in whom refracture also is common. Apophyseal stress injuries can occur in high-level athletes, especially gymnasts and throwing athletes, and if left untreated can result in a painful nonunion. The most common fractures of the olecranon are metaphyseal, either isolated or associated with other elbow injuries. The peak age is 5 to 10 years, and olecranon fractures account for approximately 5% of pediatric elbow fractures. Isolated olecranon fractures are classified by the mechanism of injury: flexion, extension, or shear. Isolated flexion fractures most commonly occur in a fall directly onto a flexed elbow. A fall onto a hyperextended elbow is the usual mechanism of injury in supracondylar humeral fractures; however, if there is a significant varus or valgus stress applied simultaneously, a metaphyseal olecranon fracture can occur. Shear injuries, which typically produce an oblique fracture line, are rare and can occur either in flexion or extension. Associated fractures occur in 50% to 75% of children with an olecranon fracture, the most common being a proximal radial fracture and type I Monteggia injury.

Treatment for stress fractures includes time away from the causative activity followed by gradual resumption of activity. Cannulated screw fixation is used for rare patients with symptomatic delayed unions or nonunions. Most olecranon fractures are nondisplaced and can be treated for 3 to 4 weeks in a long arm cast with the elbow in 70 to 80 degrees of flexion. Late displacement can occur, so these fractures need to be monitored carefully. For fractures that are displaced or that had an unsatisfactory closed reduction, open reduction and internal fixation is indicated. A variety of fixation techniques, such as percutaneous pinning, tension banding, and screw and plate fixation, have been described with good outcomes ( Fig. 36.51 ). Tension banding using bioabsorbable suture can be used in younger, smaller children to eliminate the need for implant removal. These techniques are discussed in Chapter 57 . Elbow stiffness is a common complication after olecranon fracture in children, and stable fixation is essential to start early range of motion to prevent this.

Radial Head and Neck Fractures

Isolated radial head fractures in children are rare because the immature radial head is cartilaginous. When they do occur, they usually are Salter-Harris type IV injuries in children 10 to 12 years of age. Patients with true radial head fractures are at increased risk of progressive radial head subluxation, osteonecrosis, and radiocapitellar arthrosis and need to be followed long term ( Fig. 36.52 ). Most children sustain fractures of the radial neck, which account for approximately 1% of all children’s fractures and 5% of pediatric elbow fractures.

The majority of radial neck injuries occur during a fall onto an outstretched upper extremity with the elbow in a valgus position. They typically occur in the metaphysis but can extend into the proximal radial physis producing a Salter-Harris type II pattern ( Fig. 36.53 ). Many of these fractures are angulated, with the most common direction being lateral, followed by anterior, then posterior. Radial neck fractures also can occur in conjunction with an elbow dislocation, either at the time of dislocation or during reduction ( Fig. 36.54 ). The fracture may be completely displaced or intraarticular and may block reduction. For this reason the radial neck must be thoroughly evaluated before and after reduction of a pediatric elbow dislocation.

Making the diagnosis, especially in young children, can be difficult because of the unossified radial head. In these patients the only sign of a fracture may be a small metaphyseal fragment. A radiocapitellar view can be helpful in making the diagnosis.

Due to the remodeling potential of the proximal radius, fractures with less than 30 degrees of angulation can be treated nonoperatively as long as there is no loss of forearm rotation. Patients are placed in a long arm cast for 3 weeks and then allowed to resume range-of-motion exercises. Patients with displaced, significantly angulated or displaced fractures require reduction. This consists of a stepwise approach starting with closed reduction, progressing to percutaneous-assisted reduction, and finally open reduction and internal fixation if satisfactory reduction cannot be obtained. Because there is great potential for elbow stiffness after open reduction and internal fixation, a closed reduction with slight malalignment is preferable to an open reduction and internal fixation with anatomic alignment. The loss of motion in patients with open treatment may reflect selection of most displaced fractures for open reduction and internal fixation.

Closed reduction can be performed using a variety of techniques based on the direction of displacement of the radial neck with the help of image intensification ( Fig. 36.55 ). One very useful technique is that described by Patterson. With the use of general anesthesia if needed and fluoroscopy (image intensification), an assistant stabilizes the radius distal to the fractured radial neck. With the elbow in extension and forearm rotated in the position of maximal tilt, the surgeon applies a varus stress with one hand on the elbow and lateral pressure directly over the radial head with the thumb of the other hand (see Fig. 36.60 ). Other reduction techniques have been described with the elbow in flexion. In addition, the wrapping of the arm with an Esmarch bandage has been shown to occasionally improve fracture reduction, and this maneuver should be attempted with all radial neck reduction techniques.

A percutaneous-assisted technique is used when closed techniques have failed. The most commonly used technique involves the percutaneous manipulation of the fracture with a Kirschner wire. The wire is cut, and the blunt end is used to reduce the radial neck and head to the shaft ( Fig. 36.56 ). The reduced radial neck can be stabilized by percutaneous pinning ( Fig. 36.57 ). Alternatively, a flexible intramedullary nail can be introduced retrograde from the distal radius using the technique described by Metaizeau. Using this technique, a flexible intramedullary nail is passed retrograde from the radial metaphysis proximally to the fracture site. Once engaged in the proximal fragment, the nail is rotated until the optimal reduction is obtained ( Fig. 36.58 ). The fracture is then stabilized with the nail until healing has occurred.

In open reduction and internal fixation, most surgeons use smooth pin fixation in younger children and rigid fixation in the form of screws or plates in older children or adolescents ( Fig. 36.59 ). Early rigid fixation allows early motion. This should be done through a lateral approach with the forearm in supination to protect the posterior interosseous nerve. Impediments to reduction such as capsular flaps or the annular ligament should be removed or repaired. Screws and plates should be placed in the “safe zone,” which is the 100 degrees of circumference of the radial head that does not articulate with the proximal ulna. These techniques are described in Chapter 57 .

Coronoid Fractures

Regan and Morrey classified fractures of the coronoid process as type I, a small chip fracture; type II, a fracture involving less than 50% of the process; and type III, a fracture involving more than 50% of the process ( Fig. 36.63 ). They recommended closed treatment for types I and II fractures and open reduction and internal fixation for type III fractures if possible. Operative treatment of these injuries is more common in adolescent and adult patients. This is described in Chapter 57 .

Elbow Dislocations

Acute elbow dislocation in children is rare, accounting for approximately 5% of all children’s elbow injuries. The most common type is posterior but, as in adults, dislocations can be anterior, medial, or lateral. In rare cases a proximal radioulnar joint disruption can occur ( Fig. 36.64 ). Elbow dislocations often occur in conjunction with fractures of the medial epicondyle and radial neck.

Most patients can be treated with closed reduction, a brief period of immobilization, followed by progressive protected range of motion in a splint or brace to prevent redislocation. Indications for operative treatment include entrapped intraarticular fragments (medial epicondyle, radial neck), open fracture, or associated elbow injury that will require open reduction and internal fixation.

Radial Head Dislocations (Monteggia Fracture-Dislocations)

Monteggia fractures are relatively rare, accounting for less than 1% of all pediatric elbow dislocations, with a peak age of 4 to 10 years. Although rare, they receive considerable interest because they are often missed, resulting in poor outcomes. Radial nerve injury has been reported to occur in 10% to 20% of patients, especially those with anterior and lateral dislocations because of the proximity of the radial head to the posterior interosseous nerve.

The diagnosis of Monteggia fracture can be made with standard anteroposterior and lateral radiographs of the elbow, and it is essential that the elbow be viewed in both planes for all patients with forearm fractures. A line drawn through the center of the radial neck should extend through the central portion of the capitellum regardless of elbow position ( Fig. 36.65 ). In rare instances when radiographs are equivocal, advanced imaging, such as CT, MRI, or ultrasound, should be used. The absence of trauma and changes such as a hypoplastic capitellum and a flattened convex radial head ( Fig. 36.66 ) should raise suspicion for a congenital radial head dislocation, which often is bilateral.

The most commonly used classification system is that of Bado, which is based on the direction of radial head dislocation ( Fig. 36.67 ). The most common is a fracture of the proximal third of the ulna, anterior angulation of the fracture, and anterior dislocation of the radial head (type I). The second most common is a fracture of the proximal ulna, posterior angulation of the fracture, and posterior dislocation of the radial head (type II). Lateral angulation of a proximal ulnar fracture may result in a third type with lateral dislocation of the radial head (type III), and a rare fourth type may occur with a proximal both-bone fracture and anterior dislocation of the radial head (type IV) ( Fig. 36.68 ). Although it is descriptive and straightforward, the Bado classification is not prognostic. Classification systems by Letts and Ring, based on the pattern of ulnar injury, may be more prognostic in terms of outcome given the fact that successful reduction of the ulna typically provides stability to the radiocapitellar joint ( Box 36.3 ). A study of 112 Monteggia fractures at two high-volume trauma centers found that all treatment failures, which affected 19% of patients, occurred when a less rigorous strategy than that proposed by Ring was used. In addition, there have been numerous reports of “Monteggia equivalents,” including the three most common: (1) isolated radial head dislocation (see “Isolated Dislocations of Radial Head”) ( Fig. 36.69 ), (2) fracture of the proximal ulna with fracture of the radial neck, and (3) both-bone proximal third fractures with the radial fracture more proximal than the ulnar fracture ( Fig. 36.70 ).

An isolated radial head dislocation is very rare (see Fig. 36.69 ). This is because many children thought to have an isolated radial head fracture have subtle plastic deformation of the ulna, which when corrected leads to stable radial head reduction ( Fig. 36.71 ). This must be differentiated from nursemaid’s elbow in which the radiographs are completely normal.

Successful treatment of a Monteggia fracture is dependent on correcting and stabilizing the ulnar deformity, which in turn provides stability for the radiocapitellar joint. Closed reduction and cast treatment is indicated for patients with either stable or greenstick fractures of the ulna, as well as those with plastic deformation of the ulna and satisfactory reduction of the radial head. Patients should be immobilized in a long arm cast in 90 to 100 degrees of flexion and supination and followed closely radiographically for 2 to 3 weeks to ensure maintenance of radial head reduction. Operative stabilization of the ulna is necessary with either an intramedullary nail for transverse or short oblique fractures or a plate for long oblique or comminuted fracture to provide ulnar length stability ( Fig. 36.72 ). Open reduction of the radial head combined with annular ligament reconstruction is indicated for patients with irreducible radial head dislocations caused by interposition of the annular ligament. Patients need to be followed closely postoperatively for redislocation of the radial head ( Fig. 36.73 ). Pinning of the radiocapitellar joint should be avoided when possible to prevent intraarticular pin breakage. A radiocapitellar joint unstable enough to require pinning should raise the suspicion of inadequate ulnar reduction or entrapped soft tissue.

Controversy exists as to when an acute Monteggia fracture becomes chronic. Some patients are asymptomatic while others complain of pain, decreased range of motion, or deformity. Many authors believe that, although treatment of chronic Monteggia fractures is difficult and the results unpredictable, it is better than the natural history of untreated fractures ( Fig. 36.74 ). Generally, operative treatment is more successful in symptomatic younger patients without radial head deformity. Principles of surgical reconstruction include correction of the ulnar deformity with an ulnar osteotomy and annular ligament reconstruction. The ulnar osteotomy should be stabilized in the position of maximal stability of the radiocapitellar joint, which often creates a secondary ulnar deformity that is clinically insignificant ( Fig. 36.75 , Technique 36.14). Most authors recommend reconstruction of the annular ligament, either with the native ligament itself or a strip of triceps tendon or fascia as advocated by Boyd, Lloyd-Roberts, and Bell-Tawse ( Fig. 36.76 ). Radial head resection should be avoided in younger patients because of the risk of late deformity and should only be used as a salvage procedure.

Galeazzi Fractures

Galeazzi fractures, or fractures of the radius with dislocation of the distal radioulnar joint (DRUJ), are rare in children. Most fractures of the distal forearm are associated with anterior displacement of the distal ulna unlike proximal forearm fractures, which are associated with posterior dislocations. True lateral radiographs are essential in making the diagnosis. Reduction of the radial fracture will reduce the DRUJ in most patients. In patients with irreducible fractures, open reduction and internal fixation of the distal radius should be performed and the DRUJ reassessed. If the DRUJ remains dislocated, then open reduction and internal fixation of the DRUJ should be performed to remove interposed structures, most commonly periosteum, extensor carpi ulnaris, or extensor digiti quinti tendon, and the triangular fibrocartilage complex (TFCC). The DRUJ may be pinned with the forearm supinated to provide additional stability.

Although this injury usually occurs in adolescents, a pediatric variant consisting of a Salter-Harris type II fracture of the distal ulna occurs before rupture of the TFCC can occur in a younger child. The treatment principles are the same as for adolescents; however, periosteal entrapment may block reduction rather than the TFCC.

Nursemaid’s Elbow

Nursemaid’s elbow is a subluxation of the annular ligament over the radial head, most commonly occurring in children 2 to 3 years of age when longitudinal traction is placed on the upper extremity with the elbow extended and forearm supinated. Despite the well-known mechanism of injury, 30% to 40% of patients with nursemaid’s elbow present without any history of a traction injury. Radiographs are normal in this condition, unlike Monteggia variants in which there is plastic deformation of the ulna. A variety of closed reduction techniques have been reported to be successful. A combination of forearm flexion and supination or forced hyperpronation will reduce most nursemaid’s elbows. Immobilization with a sling has been used for several days for symptomatic relief. Recurrence is high, and parents need to be counseled to avoid traction on the child’s upper limbs. Patients in which the diagnosis is unclear should be reexamined in 7 to 10 days to ensure the correct diagnosis. This usually resolves around the age of 5 years when the ligamentous structures about the elbow mature and give it more stability.

Forearm Fractures

Forearm fractures are the most common fractures in children and account for up to 40% of all pediatric fractures and, unlike in adult patients, the rate of segmental fracture is around 1%. The forearm can be divided into three regions: proximal, middle, and distal based on unique physiologic differences such as muscle forces and growth potential. Ninety percent of the growth of the forearm occurs at the distal third, giving it tremendous remodeling capacity, unlike the proximal third where very little growth and remodeling capacity exists.

Middle Third Forearm Fractures

Diaphyseal fractures of the forearm are the third most common pediatric fracture, behind the distal radius and supracondylar humerus. The most common mechanism of injury is a fall onto an outstretched hand. Many of the fractures of the midforearm in children can be treated nonoperatively, especially in young children because of the remodeling potential. The unique physiologic characteristics of pediatric bone, including its increased elasticity, increases the potential for incomplete or greenstick fractures and plastic deformation. These fractures have no remodeling potential and reduction is necessary.

Despite increased interest in operative treatment of these injuries, closed reduction with cast application remains an essential method of treatment, especially for minimally displaced fractures in younger children. Meticulous casting technique, including an intraosseous mold, straight ulnar border, three-point molding, and close follow-up to watch for late displacement or angulation, is essential for a good outcome. The cast index, defined as the sagittal cast width divided by the coronal cast width, of less than 0.7 is predictive of successful outcome ( Fig. 36.78 ). Although this was initially described for distal radial fractures, it is a good guideline for diaphyseal fractures as well.

Indications for operative treatment include open fracture, fracture in older children, loss of reduction in a cast, malunion, irreducible fracture caused by soft-tissue interposition, unstable fracture pattern, shortening more than 1 cm, and refracture after cast treatment. The need for operative stabilization of the forearm with an ipsilateral supracondylar humeral fracture has been called into question by a recent report of 17 patients treated with closed reduction and casting of their forearm fractures and had no loss of reduction. A dramatic increase in operative treatment of diaphyseal fractures in children between the ages of 5 and 12 years has been the result of the use of intramedullary nailing. The most common procedures use stable elastic intramedullary nailing of the radius and ulna, as described by Metaizeau, or plating. Studies, including a Cochrane review and meta-analysis comparing nailing with plating, showed that there was no significant difference in outcomes between the two techniques and outcomes were good in 90% of patients. Patients with intramedullary nailing had better cosmetic results but did require a second procedure to remove the implant. The Metaizeau nailing technique involves prebending of the nails to allow for restoration of the radial bow and to facilitate optimal reduction. It is important to avoid the distal radial physis and insert the nail in the radial side of the distal radius proximal to the physis. This approach avoids nail placement in Lister’s tubercle, which has been shown to have a high rate of extensor pollicis brevis tendon injury. The ulna usually is nailed antegrade either through or proximal to the proximal ulnar physis. Transphyseal nail placement is technically easier and has not been shown to cause growth arrest but is associated with a higher rate of minor implant irritation. The pins are buried below the skin, and most authors recommend a brief period of immobilization, with nail removal between 4 and 12 months after fracture when the bone is healed radiographically. Other authors have shown good results with single-bone fixation of the ulna. The advantages of this technique include decreased operative time and ease of implant removal. It is not recommended for open fractures because of the higher rate of radial malunion. Repeated attempts at closed reduction and nailing increase the risk of compartment syndrome; therefore, an open reduction should be performed after two or three unsuccessful closed attempts. The rate of delayed union primarily in the ulna using this technique is 8% to 15% and higher in boys, adolescents, those with increased fracture displacement, and those who had open reduction of the ulna.

Wrist Dislocations

Because of the proximity of the distal radial and ulnar physes to the wrist joint, wrist dislocations are extremely rare in children. When they do occur, it is usually in a skeletally mature adolescent. Treatment is similar to that in adults (see Chapter 69 ).

Scaphoid and Carpal Fractures

The carpal bones ossify relatively late in childhood; therefore fractures of the carpal bones are rare and when present can be overlooked. A recent study of MRI examination of 90 consecutive wrist injuries in patients younger than 18 years found that of the carpal fractures the most common were scaphoid fractures (83%), followed by fractures of the capitate (12%) and triquetrum (5%). Scaphoid fractures are the most common carpal injuries in children and adolescents, with peak age of 15 to 19 years. They have become more common as more children participate in competitive sports.

The scaphoid is the largest bone in the proximal row of the carpus, and ossification begins between age 5 and 6 years and is completed between the ages of 13 and 15 years corresponding with the peak incidence of fracture. Fractures of other carpal bones generally follow their times of ossification: triquetrum, 12 to 13 years; trapezium, 13 to 14 years; trapezoid, 13 to 14 years; and hamate, 15 years. The most common mechanism of injury is a fall onto the outstretched hand with the forearm pronated. This usually produces a middle third fracture. Distal third fractures usually are caused by direct trauma or avulsion and are the most common. Proximal pole fractures are the least common.

An age-based classification that is predictive of the type of injury has been developed. Type I injuries occur in children younger than 8 years and usually are chondral. Type II injuries that occur between 8 and 11 years usually are osteochondral, and type III injuries that occur in children older than 12 years are more “adult-like” because the scaphoid is ossified. Pediatric scaphoid fractures also can be classified by location: tuberosity, transverse distal pole, avulsion of the distal pole, waist, or proximal pole. In children, fractures of the distal third of the scaphoid (transverse distal pole and tuberosity) are the most common.

The most common clinical signs of scaphoid fracture are dorsal swelling of the wrist, tenderness in the anatomic snuffbox and over the distal part of the radius, and painful dorsiflexion of the wrist or extension of the thumb. Radiographs should include anteroposterior, lateral, and scaphoid views with the wrist in ulnar deviation; however, normal radiographs do not preclude the presence of a scaphoid fracture. Plain radiography is approximately 50% sensitive for the detection of a scaphoid fracture and less than 50% for the other carpal bones. If a scaphoid fracture is suggested but radiographs are negative, the wrist should be immobilized and reevaluated in 2 weeks because up to 30% of patients may have positive follow-up radiographs. MRI, which is more sensitive than CT, is useful in making the diagnosis, and a normal study as early as 2 days after injury has a negative predictive value of 100%.

Fractures of the proximal pole, although rare, seem to heal uneventfully when treated by prolonged immobilization. Avulsion fractures in the distal third of the scaphoid are common in children and usually require only cast immobilization, with healing rates approaching 95% for nondisplaced fractures. Healing times of scaphoid fractures have been described as 3 to 4 weeks for tuberosity fractures, 4 to 16 weeks for waist fractures, 4 to 8 weeks for distal scaphoid fractures, and 3 to 6 weeks for distal avulsions. Indications for operative treatment of scaphoid fractures in pediatric patients at or near skeletal maturity are similar to those for scaphoid fractures in adults. Smooth wires rather than compression screws have been used in young children to prevent growth arrest (see Chapter 69 ).

A painful nonunion of the proximal scaphoid, which in children is extremely rare, may occur after a delay in treatment generally because of an incorrect diagnosis or lack of immobilization. An established nonunion in a child may be treated operatively as in an adult. A meta-analysis of 176 surgically treated scaphoid nonunions found the healing rate to be 95%, with improvement in functional outcomes including range of motion and grip strength. A dorsal or volar approach can be used. Some authors have speculated that bipartite scaphoid may be an ununited waist fracture that has taken on the characteristics of a bipartite bone. Bipartite scaphoid usually is bilateral, asymptomatic, and not related to trauma.

Fractures of the triquetrum in children often are subtle flake avulsion or impingement fractures that require good oblique radiographs for recognition. The incidence of these fractures probably is much higher than currently known because many are misdiagnosed as wrist sprains or type I physeal injuries of the distal radius and ulna. Three weeks of cast immobilization usually is sufficient treatment.