Chapter 6: Pediatrics

Children present with different musculoskeletal injuries than are commonly seen in adults. Because ligamentous attachments are stronger than bony attachments in children, fractures are more prevalent than sprains, dislocations, and strains. This chapter discusses orthopedic injuries that are unique to the pediatric population.

The following terms are typically used in pediatric orthopedics:

• Physis: The cartilaginous growth plate that appears lucent on radiographs.

• Epiphysis: A secondary ossification center at the ends of long bones that is separated by the physis from the remainder of the bone.

• Apophysis: A secondary ossification center at the insertion of tendons onto bones.

• Diaphysis: The shaft of a long cortical bone.

• Metaphysis: The widened portion at the ends of a bone adjacent to the physis.

Evaluation of the Child

It is important to carefully palpate the uninjured extremity first to obtain the child’s confidence. It is also important to determine whether the history that is given by the parents or guardians is consistent with the observed injuries or whether there is a suggestion of child abuse.

A fracture may be difficult to find in an injured child who is crying. On physical examination, palpation of areas that are not fractured will generally hurt less than areas that are injured. Palpation should be gentle, but with enough pressure so as to make a comparison between the normal and abnormal.

Neurologic evaluation of the extremity is often difficult. A generalized withdrawal response can be evaluated by using pinprick. Wrinkling of skin suggests that the nerve is intact. In assessing the vascular status of the extremity, palpation of pulses may be difficult because of the subcutaneous fat and therefore it is important to assess and document capillary refill time.

Radiologic Examination

When performing plain radiographs of children, at least two views that are perpendicular to one another must be obtained. In addition, views of the entire extremity including both joints at the end of the long bones are integral to the patient’s evaluation. Comparison views are invaluable, particularly when looking for a subtle fracture. The growth plates in comparison views taken in exactly the same position should be closely evaluated. Anterior and posterior fat pad signs will help identify subtle fractures (Fig. 6–1). The epiphyseal centers can often be a challenge when reading plain films and therefore it is imperative that the practitioner knows when these centers begin to appear (Fig. 6–2).

Salter–Harris Classification

The Salter–Harris classification refers to physeal fractures (Figs. 6–3 and 6–4).¹ This classification is a radiologic classification and is not anatomical, nor related to the mechanism or severity of injury.

A Salter I fracture is a fracture through the physis and accounts for 6% of all physeal fractures. These fractures may be displaced or nondisplaced; however, there is no extension proximally or distally. A nondisplaced Salter I fracture may not be obvious on x-ray acutely; therefore, clinical suspicion is the key to making the diagnosis. Patients will typically present with circumferential tenderness along the physeal area. These fractures commonly occur in the distal tibia and fibula, and may present with the same mechanism as a sprained ankle without any ligamentous tenderness. In addition, these fractures occur in the hands and fingers of children.

A Salter II fracture is a fracture through the physis, which continues on into the metaphysis. These fractures account for 75% of all physeal fractures. Undisplaced fractures generally do not cause growth disturbances.

In a Salter III fracture, the fracture extends through the physis and continues into the epiphysis. These fractures account for approximately 8% of all fractures and usually occur in children who are older with a partially closed physis. These fractures should be referred early to have careful and accurate reduction.

Salter IV fractures go through the physis and into both the epiphysis and the metaphysis. These fractures account for 10% of physeal fractures. Salter IV fractures need accurate reduction to prevent bone bridging between the epiphysis and the metaphysis because these fractures involve fracture through the physis and extend both proximally and distally. This fracture and the subsequent bridging can lead to partial or a complete growth arrest.

Salter V fractures are crush injuries of the physis and are the most serious type of fracture. Fortunately, Salter V fractures only account for 1% of physeal fractures. Salter V fractures may not be clearly visible at the time of injury and are often diagnosed in retrospect when growth arrest is noted. Comparison views of the contralateral limb may be helpful in making the diagnosis acutely.

A major concern with fractures involving the physis is the potential for growth arrest or growth retardation. Salter I and II fractures have the lowest risk of growth disturbance, whereas Salter IV and V fractures have the most significant likelihood of growth disturbance. Fractures in children can result in subsequent disturbance of growth and that this is not confined to only those fractures involving the growth plates. In general, the greater the mechanism and force generated, the greater the likelihood of growth disturbance, regardless of the fracture type.

Fractures Unique to Children

The bone in children is more porous than that of adults, and thus fractures may not appear as readily. The bones of children undergo greater plastic deformation and microfractures may occur that are not seen in adults. These microfractures may not be visualized on routine x-rays and the patient may present with tenderness and the mechanism may suggest significant trauma to the bone or joint, but the radiograph will appear normal.

Torus fractures (buckle) involve a failure of bone with a compressive mechanism. These fractures occur over the metaphyseal region (Fig. 6–5). Torus or buckle fractures are very common, stable, and heal readily when immobilized. Complications are quite rare.

Greenstick fractures are incomplete fractures that result in a fracture through the tension side of a bone undergoing a deforming stress (Figs. 6–6 and 6–7). These fractures are typically angulated and may require conversion to a complete fracture to correct the deformity.

Bowing occurs when the bone undergoes plastic deformation after an injury and does not recoil back to its original position. The fibula and ulna are most commonly involved. If there is a fracture of the adjacent bone, bowing can inhibit reduction of the fractured bone.

A minimally displaced fracture may result in serious associated soft-tissue injury and visceral injuries caused by displacement of the bone during the fracture mechanism. Thus, a minimally displaced pelvic fracture may be associated with a more significant bladder, sacral plexus, or urethral injury than is seen with a similarly displaced fracture in an adult.

Joint Injuries in Children

Traumatic joint dislocations are quite unusual in children with the exception of the patellofemoral joint. The ligaments are attached to the epiphysis, and are stronger than the bone. Excessive force on a child’s joint usually results in epiphyseal injury, rather than ligamentous injury or dislocation.

Neck Injuries

The level of cervical spine injury varies with age because of the effect of the relatively large head of the child and ligamentous laxity. Therefore, when injury occurs in young children, high torques and shear forces are typically applied to the C1 to C3 region.² In children, the most common cause of injury is falls whereas in adolescents, sports injuries and motor vehicle accidents become more common. Although C-spine injuries account for less than 1% of children seen in emergency department (ED) trauma cases, the mortality rate in children younger than 8 years of age may be as high as 60%.³

Pseudosubluxation

The extreme laxity of the cervical ligaments can increase the vertebral override of adjacent vertebrae in 46% of children younger than 8 years old.² This finding, known as pseudosubluxation, is most commonly found at the C2 to C3 level (Fig. 6–8). To distinguish pseudosubluxation from true subluxation, Swischuk defined the posterior cervical line (Fig. 6–9).⁴ This line is drawn by connecting the anterior aspects of the spinous processes of C1 and C3. If the anterior aspect of the spinous process of C2 misses this line by 2 mm or more, a true subluxation or a hangman’s fracture of the neural arches of C2 should be suspected.

Spinal Cord Injury without Radiographic Abnormality

In addition to vertebral injuries seen on plain x-rays, children may also suffer spinal cord injury without plain film radiographic abnormality (SCIWORA). These injuries cause cord traction or ischemia without anatomic defects. Mechanisms that result in SCIWORA include spinal cord traction, spinal cord concussion, vertebral artery spasm, hyperextension with inward bulging of the interlaminar ligaments, and flexion compression of the cord.

In a study by Cirek et al.⁵ the incidence of SCIWORA was 6%. However, other studies show ranges between from 18% to 38%, with most cases occurring in children younger than 8 years.⁶ The upper cervical spine is involved in up to 80% of cases.⁷ Most cases of SCIWORA present with some type of neurologic symptom, most commonly paresthesias and partial cord syndromes. However, delayed onset of neurologic deficit and complete cord transection can occur.

Treatment of suspected spinal cord injuries with methylprednisolone is no longer recommended.⁸

Diskitis

Diskitis is inflammation or infection of an intervertebral disk space or a vertebral end plate. The lumbar spine is typically involved and the most common age of presentation is between 4 and 10 years. Patients present with nonspecific complaints such as refusal to walk or back pain with inability to flex the lower back. Fever is present in less than 50% of cases. On examination, percussion pain over the affected area helps to localize the site of involvement. Laboratory data are not always helpful as the white blood cell (WBC) count and blood cultures may be normal; however, the C-reactive protein (CRP) and sedimentation rate are typically elevated.⁹ Staphylococcus aureus is the organism that is most commonly involved. Although, initial x-rays of the spine may be negative, the characteristic finding is of a narrowed disk space in the involved area (Fig. 6–10).¹⁰ However, if plain films are nondiagnostic, an MRI can help to localize the lesion. Treatment involves IV antibiotics and bed rest. Some experts also recommend immobilization of the spine.

Clavicle Fractures

The clavicle is the most commonly injured bone during delivery (Fig. 6–11). Although there is a higher incidence following deliveries that require oxytocin, instrumental extraction, maneuvers for dystocia, or prolonged second-stage labor, clavicle fractures can occur during normal deliveries and Cesarean sections. In older children, fractures usually result from falls or direct blows and most commonly involve the middle third of the bone. The majority of these fractures can be managed without orthopedic referral. Fractures of the clavicle are treated with an arm sling, which is more comfortable than a figure-of-eight splint.

Elbow

The elbow is a common site for fractures in children. The typical history is a fall on the outstretched arm with hyperextension at the elbow and resultant injury to the distal humerus.

Radiologic evaluation of a child’s elbow is made more complicated due to the six ossification centers around the elbow, which appear at different ages. Comparison views of the opposite elbow should be obtained if there is any question about a possible fracture. Knowledge of the timing of the ossification centers about the elbow aids in determining whether a small piece of bone represents an avulsion fracture or an ossification center (Figs. 6–12 and 6–13).

In general, four radiographic views should be obtained to accurately assess the elbow in children. These four views obtained in the flexed elbow include the anteroposterior (AP) view of the forearm, the AP view of the humerus, the lateral view of the forearm, and the lateral view of the humerus.

Supracondylar Fractures

Horizontal fractures of the distal humerus are divided into two broad categories: supracondylar and transcondylar. Supracondylar fractures are further subdivided, based on the position of the distal humeral segment, and also on the type of injury–-extension type (posterior displacement) or flexion type (anterior displacement) (Fig. 6–14). Transcondylar fractures involve the joint capsule and also are of the flexion or extension type.

Supracondylar fractures are generally extra-articular, account for 50% to 70% of all elbow fractures, and are most commonly seen in children between the ages of 3 and 11 years. The most common mechanism encountered is a fall on the outstretched arm with the elbow in extension (Fig. 6–15). In children, the surrounding anterior capsule and collateral ligaments are stronger than the bone, and fractures rather than ligamentous tears usually result. Extension-type supracondylar fractures account for 95% to 98% of all supracondylar fractures and 20% to 30% of supracondylar fractures will have little or no displacement.¹¹ In children, 25% of supracondylar fractures are of the greenstick type.¹² Radiographic diagnosis in these cases may be exceedingly difficult.

There are three types of supracondylar extension fractures. Type I supracondylar fractures are nondisplaced or minimally displaced. Type II supracondylar fractures have angulation of the distal fragment–-posterior displacement with extension-type injuries and anterior displacement with flexion-type injuries. Type III supracondylar fractures involve fractures of both cortices and are completely displaced.

Examination

With nondisplaced fractures there may be little swelling (Fig. 6–16A). When displaced, the deformity is usually more obvious and the distal humeral fragment can often be palpated posteriorly and superiorly due to the pull of the triceps muscle (Fig. 6–17A). As swelling increases, this injury can be confused with a posterior dislocation of the elbow resulting from the prominence of the olecranon and the presence of a posterior concavity. In addition, the involved forearm may appear shorter when compared with the uninvolved side.

Imaging

Routine views must include AP and lateral projections in comparison with the uninvolved extremity in children. Oblique views may also be helpful. In the case of displaced fractures, the injury is quite obvious (Fig. 6–17B).

Subtle changes, such as the presence of a posterior fat pad or an abnormal anterior humeral line, may be the only radiographic clues to the presence of a fracture (Fig. 6–16A and Fig. 6–18. The anterior humeral line (Fig. 6–18) is a line drawn on a lateral radiograph along the anterior surface of the humerus through the elbow. Normally, this line transects the middle third of the capitellum. With a supracondylar extension fracture, this line will either transect the anterior third of the capitellum or pass entirely anterior to it (Fig. 6–19A). The anterior humeral line of a flexion injury passes posterior to the capitellum (Fig. 6–19B).

Another diagnostic aid in evaluating radiographs of suspected supracondylar fractures in children is to determine the carrying angle. The intersection of a line drawn through the midshaft of the humerus and a line through the midshaft of the ulna on an AP extension view determines the carrying angle (Fig. 6–20). Normally, the carrying angle is between 0 and 12 degrees. Traumatic or asymmetric carrying angles of greater than 12 degrees are often associated with fractures.

Elevation of the fat pad in the coronoid fossa (anterior fat pad sign) and olecranon fossa (posterior fat pad sign) occurring due to an effusion from trauma or an infection is an important feature to investigate. A posterior fat pad is always pathologic and raises the index of suspicion for a fracture. An anteriorly displaced fat pad, the “sail sign” may also be an indication of an occult fracture.

Associated Injuries

Distal humeral fractures are frequently associated with neurovascular complications, even in the absence of displacement. The most commonly injured structures are the median nerve and the brachial artery. Initially, document the presence and strength of the radial, ulnar, and brachial pulses. The presence of a pulse, however, does not exclude a significant arterial injury. Also examine and document the motor and sensory components of the radial, ulnar, and median nerves. The three types of nerve injuries are contusion, partial severance, and complete severance.

Caution: Subsequent manipulation may result in serious neurovascular compromise.

Brachial artery compromise is not an uncommon complication and can lead to compartment syndrome. The compartment syndrome leads to diminished perfusion and loss of function of the muscles within the forearm. An intact radial pulse at the wrist has no merit in ruling out the evolution of a compartment syndrome or in evaluating the perfusion to the forearm. Review the detailed discussion of compartment syndromes presented in Chapter 4.

Treatment

Nondisplaced (type I) fractures are treated with cast immobilization. The extremity is placed in a posterior long-arm splint extending from the axilla to a point just proximal to the metacarpal heads. The splint should encircle three-fourths of the circumference of the extremity (Appendix A–9). The elbow should be between 90 and 100 degrees of flexion. The distal pulses should be checked and, if absent, the elbow is to be extended 5 to 15 degrees or until the pulses return. A sling for support and ice to reduce swelling are applied.

Although nondisplaced fractures are rarely associated with complications, even a radiographically occult fracture can result in compartment syndrome, a pulse deficit, or neuropathy. Only the most stable fractures with minimal swelling after a period of 6 to 12 hours of observation can be safely discharged. Consultation with an orthopedic surgeon who will take responsibility for the care of the patient should be obtained before the patient leaving the ED.

All displaced fractures require emergent consultation with an experienced orthopedic surgeon and admission for neurovascular monitoring. Manipulative reductions are at times difficult to perform and fraught with complications. Emergent reduction by the emergency specialist is indicated only when the displaced fracture is associated with vascular compromise, which immediately threatens the viability of the extremity.

Definitive management of flexion type II fractures includes reduction and casting in extension. Percutaneous pinning may be necessary. Closed reduction and pinning has been found to be effective for the treatment of pediatric supracondylar humerus fractures.^{13 , 14} Extension type II fractures are also treated with reduction and percutaneous pinning.

Extension type III fractures often require open reduction and pinning because of difficulty with closed reduction attempts. Flexion type III supracondylar fractures may also require open reduction and percutaneous pinning.

Open reduction with internal fixation is indicated under the following circumstances:

1. Inability to achieve a satisfactory closed reduction

2. Complicating fractures of the forearm

3. Inability to maintain a closed reduction

4. Vascular compromise

Delayed swelling with subsequent neurovascular compromise is frequently noted following displaced supracondylar fractures and therefore admission for close monitoring is recommended.

Complications

Complications of supracondylar fractures include neurovascular injuries, compartment syndrome, ulnar nerve palsy, joint stiffness, and cubitus varus and valgus deformities (because of malposition of the distal humeral fragment after reduction). Diminished range of motion may be secondary to inadequate reduction or callus formation within the joint. The median nerve and radial nerve are injured commonly. When the anterior interosseous nerve is injured, there is loss of thumb interphalangeal joint flexion and the index distal interphalangeal joint flexion.

Medial Epicondylar Fractures

Epicondylar fractures are most commonly seen in children (Fig. 6–21). Medial epicondylar fractures are more common than lateral epicondyle fractures.

The ossification center for the medial epicondyle appears by age 5 to 7 and fuses to the distal humerus by age 20. Medial epicondylar displacement as an isolated injury is uncommon. More commonly seen is the palpable avulsion fracture associated with a posterolateral dislocation of the elbow (Fig. 6–22). The typical age of presentation is 7 to 15 years with medial epicondyle fractures accounting for 10% of elbow fractures in children.

There are three mechanisms commonly associated with fractures of the medial epicondyle.

1. The more common avulsion fracture is associated with childhood or adolescent posterior dislocations. This fracture is rarely associated with posterior dislocations over the age of 20.

2. The flexor pronator tendon is attached to the medial epicondylar ossification center. Repeated valgus stress on the elbow may result in a fracture with fragment displacement distally. This is commonly seen in adolescent baseball players and is called “little league elbow.”

3. Isolated medial epicondylar fractures in adults are usually due to a direct blow.

If this fracture is associated with a posterior dislocation, the elbow will be in flexion and there will be a prominence of the olecranon. The elbow dislocation is reduced (see Chapter 14) and fracture fragments assessed. If the epicondyle is within the joint, open reduction is indicated. Isolated fractures produce localized pain over the medial epicondyle. Pain is increased with flexion of the elbow and the wrist, or with pronation of the forearm. When assessing this fracture, the physician must examine and document ulnar nerve function before initiating therapy. Displaced fragments may migrate and become intra-articular.

Caution: Radiographically, if the fragment has migrated to the joint line it should be considered intra-articular.

Fragments that are displaced less than 5 mm, as determined by measuring the clear space between the fracture fragment and the humerus; can be immobilized in a long-arm posterior splint (Appendix A–9). The elbow should be flexed with the forearm pronated and the wrist held in a flexed position. The splint should remain in place and the patient is referred. Fragments with 5 mm or more are more controversial with some experts advocating for open reduction and internal fixation and others supporting an initial trial of closed management. The individual case should therefore be discussed with the consulting orthopedist.

Medial Condyle Fractures

In young children, medial condylar fractures are often difficult to diagnose radiographically especially if the injury occurs before the trochlea ossifies. For this reason, it is easy to assume that the fracture is of the medical epicondyle. In older children, a metaphyseal fragment may be visualized and this helps to identify condylar involvement. Comparison views of the uninjured elbow may be helpful in differentiating a fracture from a secondary ossification center.

One of the most serious complications of a medial condyle fracture is bleeding and swelling of the closed fascial space leading to the development of a compartment syndrome. Fractures with more than 2 mm of displacement generally require surgical fixation.

Lateral Condyle Fractures

Lateral condyle fractures frequently require open reduction and fixation as they are transphyseal and intra-articular. These fractures typically occur from a fall onto an outstretched arm. Oblique views of the elbow may help to determine whether or not the fracture is displaced. The lateral epicondyle is the last ossification center to appear. One classification of lateral condyle fractures describes the fractures as nondisplaced (<2 mm), minimally displaced (2–4 mm), or displaced (>4 mm).

The management of minimally displaced lateral condyle fractures is controversial–-casting, percutaneous fixation, and open reduction have all been used with success. However, displaced lateral epicondyle fractures should undergo open reduction and pinning. Complications of lateral epicondyle fractures include cubitus valgus deformity, lateral transposition of the forearm, arthritis because of joint capsule and articular disruption, ulnar nerve palsy, and overgrowth with subsequent cubitus varus deformity.

Radial Head and Neck Fractures

Epiphyseal fractures of the radial neck are classified on the basis of the degree of angulation (Fig. 6–23). When the epiphysis is not yet ossified and one suspects a nondisplaced radial head fracture, look at the radiocapitellar line (Fig. 6–24). A line drawn through the midportion of the radius normally passes through the center of the capitellum on the lateral view of the elbow. In a subtle fracture at the epiphysis of the radial head, this line will be displaced away from the center of the capitellum. This may be the only finding suggesting a fracture in a child.

Radial head and neck fractures often require oblique views for radiographic visualization. Impact fractures of the neck are best seen on the lateral projection. The presence of a bulging anterior fat pad or a posterior fat pad sign is indicative of significant joint capsule distension.

Fractures with angulation of less than 15 degrees are best treated with immobilization for 2 weeks in a long-arm posterior splint (Appendix A–9). This should be followed by active exercises with a sling for support. Remodeling will generally correct this degree of angulation. With angulation of greater than 15 degrees, the arm should be immobilized in a posterior splint, and the patient admitted for reduction under general anesthesia. Reduction attempts in children without good anesthesia are difficult to perform and fraught with complications.

Angulation of greater than 60 degrees is regarded as complete displacement and usually requires open reduction. Limited success has been achieved with manipulative reductions.

Osteochondritis Dissecans

Osteochondritis dissecans occurs in young athletes who overload and hyperextend the elbow. Gymnasts are constantly loading their elbows as they balance on beams and high bars and are particularly susceptible to this condition. The symptoms that occur are locking, giving way, and crepitus on range of motion. Radiographs may reveal a loose body within the joint or demonstrable osteochondritis dissecans. MRI is often helpful in suspicious cases when the x-ray is negative.

Treatment is conservative unless there are loose bodies within the joint that require mechanical removal. Conservative treatment for acute exacerbations consists of splinting the elbow for 3 to 4 days, anti-inflammatory medications, and the application of heat. If mechanical symptoms occur and persist, arthroscopic intervention to remove and debride loose bodies is necessary.

Little League Elbow

“Little league elbow” occurs when young throwers typically between the age of 9 and 11 years, have repetitive microtrauma at the ossification center along the radial head. Osteochondral changes in the capitellum, premature proximal radial epiphyseal closure, and fragmentation of the medial epicondyle are collectively known as little league elbow. The condition is predominantly a result of forces applied during a late phase of throwing causing a valgus strain of the elbow. Comparison views on x-rays show that the apophysis has become separated. Bony fragments can ultimately lodge in the joint and require open reduction and removal. Loss of extension occurs as a result of tightening of the ulnar collateral ligament, producing pain and varus stress. Ulnar neuritis may present because of subluxation or compression of the fascial planes. Arthroscopy may be required particularly if a bone fragment is noted. Treatment includes rest, ice, and the institution of routine stretching and range of motion exercises prior to overhand pitching.

Radial Head Subluxation (Nursemaid’s Elbow)

Nursemaid’s elbow (radial head subluxation) is a common orthopedic injury occurring in early childhood. The peak incidence is in the toddler years; however, the condition does occur in the first year of life and has been described as late as 31 years of age.¹⁵ The annular ligament provides support for the radial head, maintaining the head in its normal relationship with the humerus and the ulna. In children, there is little structural support between the radius and the humerus. With sudden traction of the hand or the forearm, nursemaid’s elbow occurs when a parent pulls a child up by the arm to prevent a fall; the annular ligament is pulled over the radial head and is interposed between the radius and the capitellum (Fig. 6–25).

Children with nursemaid’s elbow present because of disuse of the affected arm and will be noted to hold the arm at their side with the forearm in a pronated position (Fig. 6–26). It is important to note that patients with nursemaid’s elbow do not have swelling, warmth, or ecchymosis about the elbow. Radiographs should be performed prior to reduction attempts in cases in which aspects of the history (e.g., witnessed direct trauma to the upper extremity) and examination findings (e.g., swelling, bruising, and warmth over the joint) suggest that infection or fracture is more likely than radial head subluxation. Patients who present with a history and examination findings consistent with nursemaid’s elbow need not undergo radiography prior to reduction attempts.

Treatment

Two different methods are commonly used for reducing a nursemaid’s elbow. Prospective studies comparing the two methods reveal that the hyperpronation technique has a higher initial success rate (95%) than the supination/flexion technique (77%).^16–18

Hyperpronation Technique. The hyperpronation method involves the examiner cradling the child’s elbow with one hand (with thumb or forefingers overlying the radial head) while the other hand is used to hyperpronate the child’s forearm by holding and turning the child’s hand into a hyperpronated position. With successful reduction, a “click” will be felt about the child’s elbow by the examiner (Fig. 6–27 and Video 6–1).

Supination/Flexion Technique. The supination/flexion technique involves the examiner cradling the child’s elbow with one hand (again, with thumb or forefingers over the radial head) and supinating the patient’s hand completely. The examiner then fully flexes the child’s elbow by bringing the supinated hand up toward the shoulder. With successful reduction, a “click” will be felt near the elbow (Fig. 6–28 and Video 6–2).

Regardless of which reduction technique is used, the child will typically begin to use the arm normally within 10 to 15 minutes. A failed reduction attempt should be followed by a second attempt using either the same or alternate technique. The second attempt often meets with success. If the reduction is unsuccessful after two or three attempts, radiographs of the upper extremity should be obtained to help exclude fracture or other pathology as the cause of the child’s symptoms.

The child with a successfully reduced nursemaid’s elbow does not need specific follow-up with the primary caregiver unless symptoms (pain or disuse of the arm) return. Parents and caregivers should be cautioned about refraining from any activity that involves pulling on the child’s arm, as the condition recurs in approximately 25% of children who have experienced at least one episode.¹⁹

A patient who does not respond to nursemaid’s elbow reduction attempts will require close primary care follow-up and possibly orthopedic consultation.

Forearm

Radius and Ulna Shaft Fractures

The most common childhood fractures are those involving the radius and ulna (Fig. 6–29 and Video 6-3). In most children with forearm fractures, both bones are usually fractured. When only one forearm bone is fractured, the emergency physician should look for evidence of dislocation of the proximal or distal radioulnar joints. Monteggia fractures involving the proximal ulna associated with a radial head dislocation are sometimes missed. The radial head should always be in good alignment with the capitellum. Galeazzi fractures involve a distal radius fracture associated with a distal radioulnar dislocation. For more information on these fractures, the reader is referred to Chapter 13.

Wrist

Distal Radius and Ulna Fractures

The distal radial physis is the most commonly fractured growth plate. Salter II injuries are the most common, accounting for 58% of these fractures.²⁰

Ulnar physeal injuries are less common and occur in only 5% of distal forearm fractures. The thick, triangular fibrocartilage complex protects the distal ulnar physis, but concentrates force on the attachment to the styloid. Unfortunately, distal ulnar growth arrest occurs in approximately 55% of these fractures when they are associated with distal radius fractures.²⁰ Salter I injuries are the most common pattern occurring in half of patients. Approximately 70% to 80% of the longitudinal growth of the ulna comes from the distal physis. Thus, growth arrest can cause significant shortening as well as a milder radial shortening because of a tethering effect.

Displaced or angulated distal forearm fractures in children, unlike adults, have a great ability to remodel. They rarely lead to dysfunction. Thus, angulation of a distal forearm fracture of at least 20 degrees can be accepted in the younger child, especially those younger than 10 years. In children with minimally angulated fractures of the distal radius, Boutis et al. found that the use of a removable splint was as effective as a cast with respect to the recovery of physical function. In addition, the devices were comparable in terms of the maintenance of fracture stability and the occurrence of complications.²¹

Distal Radius Epiphyseal Separation—Extension Type

This injury usually results from a fall on an outstretched hand with forced dorsiflexion of the hand and epiphyseal plate. The typical result is a Salter I or II fracture of the epiphysis (Fig. 6–30). Growth arrests are uncommon but may occur, and therefore these fractures require orthopedic referral. It is important to exclude the diagnosis of epiphyseal slip, as these fractures require emergent reduction (Fig. 6–31).

In treating these injuries, more angulation and displacement can be accepted. Reduction is recommended for angulation of greater than 25 degrees or displacement of greater than 25% of the radial diameter. Immobilization is accomplished by one of two means. For stable fractures, a short-arm AP splint should be applied with the forearm in supination and the wrist in slight extension. For unstable fractures, immobilization in a long-arm AP splint (Appendix A–10) is recommended with the forearm in supination and the wrist in flexion. Some authors advocate placing the wrist in extension. Others feel that extension of the wrist should be avoided as it places a volar distracting force against the fracture. If the fracture is unstable after a closed reduction, pin fixation or open reduction with internal fixation is advocated.

Pelvis

Iliac Crest Apophysitis

Iliac crest apophysitis is an overuse injury commonly seen in runners and hockey, soccer, and football players. The main symptom is pain over the affected iliac crest that is worsened with running. Plain radiographs are normal. Treatment is conservative and includes anti-inflammatory medication.

Hip

Developmental (Congenital) Hip Dislocation

Developmental hip dislocation, previously known as congenital hip dislocation, is an intra-articular displacement of the femoral head from its normal position within the acetabulum. This leads to an interruption in the normal development of the joint occurring before or shortly after birth. At birth, the acetabular fossa is shallow with the superior portion of the acetabulum poorly developed, offering little resistance to the upward movement of the head by muscle pull or weight bearing. This leads to a condition called congenital subluxation of the femoral head, in which the femoral head is displaced laterally and proximally, and articulates with the outer portion of the acetabulum. In complete dislocation of the hip, the femoral head is located completely outside the acetabulum and rests against the lateral wall of the ilium. Later, a false acetabulum forms with a capsule interposed between the femoral head and the ilium.

In the normal infant, one sees folds in the groin, below the buttocks, and several along the thigh, which are symmetrical. In subluxation or dislocation, these folds will be asymmetrical. When the examiner places the infant on the table, the pelvis and the limb on the affected side will be pulled proximally by muscle action. This proximal displacement causes apparent shortening of the limb.

The Ortolani click test is performed as a routine part of the examination on infants before 1 year of age. In the normal infant, when the hip is flexed 90 degrees and the thigh is abducted, the lateral aspect of both thighs will nearly touch the table. In subluxation or dislocation, abduction is restricted and the involved hip is unable to be abducted as far as the opposite one, producing an audible or palpable click as the femoral head slips over the acetabular rim (Fig. 6–32).

The Barlow provocative test is performed with the newborn positioned supine and the hips flexed to 90 degrees. The leg is then gently adducted while posteriorly directed pressure is placed on the knee. A palpable clunk or sensation of movement is felt as the femoral head exits the acetabulum posteriorly. The Ortolani and Barlow maneuvers are performed one hip at a time.

Repeat examination of the infant is mandatory until the child starts walking because the lack of symptoms and subtle physical findings make early diagnosis difficult. Patients with late-presenting developmental dysplasia of the hip (DDH) will typically present with a painless limp. There is usually a history of a delay in walking with the age of onset being between 14 and 15 months, instead of 12 months. The affected lower leg may be shortened. If the DDH is bilateral, the toddler may walk with a waddle. A radiograph of the pelvis after 4 months of age will help to confirm the diagnosis (Fig. 6–33). Ultrasound may be effective for early diagnosis of this disorder in infants of less than 4 to 6 months.²² However, the use of screening ultrasounds is not recommended. Close physical examination and referral to orthopedics for suspected cases is appropriate.²³

Legg–Calvé–Perthes Disease (Coxa Plana)

Legg–Calvé–Perthes disease (LCPD) is an idiopathic form of avascular necrosis of the femoral head occurring in children (Fig. 6–34). This condition, which affects boys three to five times more often than girls, occurs most often in children between 4 and 9 years.

The definitive cause of the vascular disturbance resulting in LCPD is unknown. The condition results in necrosis of the head and all or part of the epiphysis. An almost constant early sign is a limp, which is caused by limited abduction of the hip and limited internal rotation in both flexion and extension. The patient complains of a vague ache in the groin that radiates to the medial thigh and inner aspect of the knee. This is aggravated by activity and relieved by rest. The patient may also complain of stiffness in a joint, and tenderness is noted over the anterior aspect of the joint. Muscle spasm is another common complaint in the early stages of the disease.

The early signs on x-ray are of joint space widening and prominence of the soft tissues over the capsule with a minimal joint effusion. The femoral head may be shifted slightly laterally in the acetabulum. A few weeks later, the femoral head will appear denser than the rest of the bone. Later, a fragmented appearance on the radiograph is evidence of necrosis; ingrowth of new vessels initiates the process of reabsorption. This results in a decreased density of the proximal end of the metaphysis because of increased vascularity. Osteosclerosis with broadening and shortening of the femoral neck and an increased density of the head is also seen. Eventually, osteoarthritis develops.

Initial therapy includes minimal weight bearing and protection of the joint, which is accomplished by maintaining the femur abducted and internally rotated. This will keep the femoral head well inside the rounded portion of the acetabulum. Abduction and rotation of the femur is accomplished either by the use of orthotic devices (bracing) or surgery (osteotomy).

The Scottish Rite brace achieves containment by abduction, while allowing free knee motion. This brace allows the hip to flex to 90 degrees, but it cannot control the rotation of the hip. In older patients with more extensive femoral head involvement, surgical repair results in improved outcome when compared with nonsurgical management.^24,25

Slipped Capital Femoral Epiphysis

Slipped capital femoral epiphysis (SCFE) occurs in children between the ages of 10 and 16 years with a male predominance. Patients are typically overweight with over 80% of patients having a body mass index above the 95th percentile.²⁶ In approximately one-fourth of the cases both hips are affected. There is an increased frequency of this disorder in patients with endocrine disorders, including hypothyroidism, growth hormone deficiency, and hypogonadism. The capital femoral epiphysis is weakened and displaced downward and backward, resulting in a very disabling external rotation deformity of the lower extremity that later goes on to form degenerative arthritis of the hip.

In many of these patients, there is a history of rapid skeletal growth before the displacement. The patient may present to the ED with a history of minor trauma or strain, but persistent symptoms. This condition is found in children who are typically obese with underdeveloped skeletal characteristics, and is less commonly seen in tall, thin children. Weight bearing and muscle contraction cause the displacement to worsen. Young athletes between the ages of 8 and 12 years with knee discomfort and no effusion should be investigated for SCFE.

On examination, the hip is externally rotated and there is pain and diminished range of motion to internal rotation, abduction, and flexion. When this occurs, the patient’s diagnosis is clear and the approach is fairly straightforward. Often, clinical findings are subtle and may be missed.²⁷

Three clinical stages exist. In the preslipping stage, there is slight discomfort about the groin, which usually occurs after activity and subsides with rest. The patient may complain of stiffness and an occasional limp. Discomfort may radiate along the anterior and medial aspect of the thigh to the inner aspect of the knee. The symptoms are usually vague, and no objective findings are noted on physical examination. The second stage is the chronic slipping stage, where the epiphysis is separated and gradually shifts backward, as is usually noted on x-rays taken during that time. In this stage, a patient has tenderness around the hip joint and limitation of motion (particularly abduction and internal rotation). The limb develops an adduction and external rotation deformity. As the hip is flexed and externally rotated, the slipping is accentuated, and the gluteus medius becomes inadequate. The patient develops a positive Trendelenburg test. When the condition is bilateral, the patient has a waddling gait. This is followed by a stage of fixed deformity in which pain and muscle spasm disappear. The limp and external rotation and adduction deformity persist, as does the limitation of internal rotation and abduction.

AP views of both hips should be taken (Fig. 6–35A). In addition, a lateral view taken in a frog position, with the hip flexed 90 degrees and abducted 45 degrees, will demonstrate the displaced capital femoral epiphysis (Fig. 6–35B). In the preslipping stage, a globular swelling is seen in the joint capsule. This is accompanied by widening of the epiphysis and decalcification of the metaphysis at the epiphyseal border caused by inferior and posterior slipping of the head. Other clues to the diagnosis of slipped epiphysis include a wide irregular or mottled epiphyseal plate, metaphyseal rarefaction, and periosteal new bone formation. Kline’s line, a line drawn through the superior border of the proximal femoral metaphysis, should intersect part of the proximal femoral epiphysis. If this does not occur, SCFE should be suspected (Fig. 6–36). Comparison of this line’s intersection to the other hip is helpful in subtle cases. In addition to this, loss of Shenton’s line is a commonly seen radiographic finding (Fig. 6–37). When the relationship of the femoral head to the acetabulum is uncertain on the plain radiographs, a CT scan is often able to diagnose the problem readily.

These cases must be diagnosed early, and once suspected, referred immediately to the orthopedic surgeon for definitive treatment. This involves reduction of the slipped epiphysis and no weight bearing. The priorities in treating an unstable (acute) slip are to avoid avascular necrosis, avoid chondrolysis, and prevent further slip as well as correct the deformity.

Transient Synovitis

Transient synovitis is the most common cause of acute hip pain in children between 3 and 10 years of age. Typically, these children present with hip pain of 1 to 3 days duration, accompanied by a limp or a refusal to bear weight. The extremity is held in flexion, adduction, and internal rotation, while the child resists all attempts at passive motion resulting from muscle spasm. The temperature is usually normal to slightly elevated, and is rarely high. This condition has an uncertain etiology and is diagnosed through a process of exclusion. Patients often report a preceding viral or bacterial infection. The disorder is usually unilateral, although it can be bilateral. The treatment for transient synovitis is rest and anti-inflammatory medication with close follow-up.²⁸

Septic arthritis must first be ruled out, because femoral head destruction and degenerative arthritis will result if septic arthritis is not treated promptly. These patients, unlike patients with transient synovitis, are toxic in appearance and generally have high fevers. The patient resists any attempts at range of motion. When the diagnosis is unclear (temperature <102°F, limited range of motion, and negative ultrasound), a brief period of observation after a dose of ibuprofen may help differentiate the two entities, as the child with transient synovitis will improve.

However, if any doubt exists as to the etiology of the pain, blood cultures, antibiotics, aspiration of the hip joint, and culture of the synovial fluid are mandatory.

Septic Arthritis and Osteomyelitis

Septic arthritis and osteomyelitis are not uncommon in children. The pathologic origin is hematogenous seeding, local invasion from contiguous infection, or direct inoculation of the bone, either surgically or after trauma.

The presentation of septic arthritis is usually that of a fever, which may be low grade, and what is called pseudoparalysis, which essentially is a refusal of the child to use that limb. Gentle passive motion, however, is usually allowed. Presenting symptoms in neonates may be as vague as increased irritability, fever, or poor feeding. Children with osteomyelitis have tenderness to palpation particularly over the metaphysis, which is commonly affected. When the hip and shoulder are involved in osteomyelitis, the pus can track under the periosteum of the metaphysis into the adjacent joint and thus the patient may have findings of both osteomyelitis and septic arthritis. The diagnosis of osteomyelitis can be made by the presence of any two of the following diagnostic criteria:

• Purulence of the bone

• A positive bone or blood culture

• Localized erythema, edema, or both

• A positive imaging study, either on radiography, scintigraphy, or MRI

Cultures taken from bone result in a culture yield of 80%. Blood cultures should be drawn on all patients suspected of having osteomyelitis, as they are positive in up to 50% of patients. The most common organisms involved in newborns include staphylococci, Haemophilus influenzae, and gram-negative bacilli. In infants and children, S. aureus is the most common major organism. However, Goergens et al.²⁹ found methicillin resistant S aureus to be an emerging organism contributing to 6% of septic arthritis cases. H. influenza disease is no longer a threat due to universal vaccination except in neonates and unimmunized children. Neisseria gonorrhoeae should be suspected in sexually active teenagers. Patients with sickle cell disease are also at risk for Salmonella-related osteomyelitis.

Jung et al. in a univariate analysis showed significant differences in body temperature, serum WBC count, erythrocyte sedimentation rate (ESR), and CRP levels between patients with septic arthritis versus transient synovitis. Plain radiographs showed a displacement or blurring of periarticular fat pads in patients with acute septic arthritis, and multivariate regression analysis revealed that a fever, ESR greater than 20 mm/h, CRP greater than 1 mg/dL, WBC greater than 11,000/mL, and an increased hip joint space of greater than 2 mm were independent predictors of acute septic arthritis.³⁰ In a prospective study of patients with suspicious physical examination findings, Caird et al.³¹ found that fever (an oral temperature >38.5°C) was the best predictor of septic arthritis followed by an elevated CRP level, an elevated ESR, refusal to bear weight, and an elevated serum WBC count. In their study group, a CRP level greater than 2 mg/dL (>20 mg/L) was a strong independent risk factor for having septic arthritis of the hip.

The femur and tibia are by far the most common bones affected. Plain films are generally normal and it takes 7 to 10 days for radiographic changes to appear in either osteomyelitis or septic arthritis.³² Soft tissue, however, may show changes earlier. The younger the child, the more likely one is to see widening of the joint space. Abnormal subluxation of the hip with widening of the joint space is the most common x-ray finding. Because plain x-rays are usually not helpful early in the course of this disease, a low threshold should be used for skeletal scintigraphy. Scintigraphically guided aspiration of the hip evacuates pus, decreases damage to periarticular surfaces, differentiates joint sepsis from other effusions, and helps direct antibiotic therapy. CT scans are not useful in establishing a diagnosis of acute musculoskeletal sepsis.³³

In treating children with osteomyelitis and septic arthritis, β-lactamase-resistant antibiotics should be included particularly due to the prevalence of MRSA .In patients who are allergic to penicillin, clindamycin 24 mg/kg in divided doses over 24 hours, or vancomycin is indicated.³⁴

Knee and Leg

Osgood–Schlatter Disease

Osgood–Schlatter disease represents a disturbance in the development of the tibial tuberosity caused by repeated and rapid application of tensile forces by the quadriceps muscles at its tendinous insertion on the tuberosity.^{35 , 36} The most widely accepted cause of Osgood–Schlatter disease is chronic repetitive trauma to the anterior portion of the maturing proximal tibial growth plate.

This disease is typically seen in girls between 8 and 13 years of age and in boys between 10 and 15 years. The disorder has been associated with inflexibility of the quadriceps muscle. The condition is usually unilateral, but it may be bilateral in 35% to 56% of boys and approximately 18% of girls.³⁷ In addition, boys are affected more often than girls.

On examination, there is typically pain, swelling, and tenderness localized over the tibial tubercle (Video 6–4). Joint effusion should not be present. Quadriceps used against resistance aggravates the pain, particularly during climbing steps, squatting, or kneeling. These symptoms are secondary to incomplete separation of the cartilaginous link between the patellar tendon and the tibia. The separation interrupts the blood supply, resulting in aseptic necrosis, fragmentation, and eventually new bone formation (Fig. 6–38). Fusion of the tubercle to the tibia occurs by 18 years of age, thus eliminating any further symptoms. MRI and ultrasound of the knee have been shown to be superior to plain radiographs in diagnosing Osgood–Schlatter disease.³⁸ However, neither of these studies is immediately necessary in the ED.

The treatment includes a reduction of activity (i.e., sprinting, jumping, and kicking) for 2 to 4 months, ice after exercise and a short course of nonsteroidal anti-inflammatory medications.³⁹ Resolution of symptoms may take up to 12 to 18 months.⁴⁰ Stretching exercises for the quadriceps and hamstrings are also helpful. Complete restriction of all athletic activities is generally not necessary. Corticosteroid injections are not recommended due to the risk of subcutaneous atrophy and degenerative changes. Some patients develop chronic pain, which is associated with a discrete ossicle in the patellar tendon. Surgical treatment can provide relief in these patients.⁴¹ Immobilization is not generally recommended except in severe or persistent cases.

Patella Apophysitis

Apophysitis of the inferior pole of the patella is referred to as Sinding–Larsen–Johansson disease. This condition is also called inferior pole patellar chondropathy and is nine times more prevalent in boys between the ages 10 and 14 years than it is in girls. Patients present with lower-pole patellar pain exacerbated by running or kneeling. On examination, pain is noted with extension against resistance along with localized tenderness on the inferior pole of the patella. With protracted symptoms, there is an elongation of the involved pole, which may develop a stress fracture and eventually an avulsion fracture if not diagnosed. Radiographs are usually normal, although blurring of the poles may be seen in chronic cases. The treatment is similar to Osgood–Schlatter disease. Nonsteroidal agents and rest are recommended. This condition is self-limited and usually resolves completely within 12 to 18 months. In rare cases, a 2- to 3-week trial of crutches is necessary.

Patellofemoral Stress Syndrome

Patellofemoral stress syndrome is the most common complaint in young female athletes. The common presentation is of aching knees, with pain increased by jumping or climbing. Physical findings usually include pain on compression of the patellar region; joint effusion and swelling are rare. Plain films are normal. Treatment includes relative rest and physical therapy.

Ligamentous Injuries

Ligamentous injuries involving the knee are uncommon in children because the bone is weaker than the ligaments. In the knee, an adult will experience a talofibular ligament rupture, whereas a child more frequently suffers a Salter I orII fracture of the proximal tibia or distal femur. Following a rotational injury or varus stress to the knee in a child, an avulsion of the tibial spine occurs more frequently than an anterior cruciate ligament rupture. By the same token, it is more common in the adult to have a rupture of the patellar tendon or quadriceps tendon from an extension-block injury to the quadriceps apparatus, whereas a child is more likely to suffer an avulsion of the tibial tubercle. Subtle and occult fractures are common in children. For this reason, a child with an effusion following a knee injury and negative plain radiographs should be immobilized and referred.

In dealing with a patellar injury or dislocation, always remember to examine the undersurface of the patella, as osteochondral chip fractures are more common in children than in adults.

Toddler’s Fracture

A toddler’s fracture is a nondisplaced spiral or oblique fracture of the lower third of the tibial shaft. This fracture occurs in patients between the ages of 9 months and 3 years. This injury results from torsion of the lower leg (Fig. 6–39). A fibula fracture is not present. Often, the parents do not recall any trauma and the only complaint is difficulty walking or resistance to weight bearing. Physical examination often fails to reveal swelling, but may show increased warmth and pain with palpation of the lower third of the tibia.

AP and lateral films may reveal an obvious fracture; however, oblique films may help to confirm the fracture. Initial radiographs may appear normal; however, 2 to 3 weeks later subperiosteal bone formation may be seen.

The treatment of radiographically confirmed toddler’s fracture consists of a below-knee walking cast for approximately 3 weeks. The treatment of a presumed toddler’s fracture, in which no fracture is visualized on the initial radiograph, is somewhat controversial. Some advocate splinting for comfort and repeat radiographs in 10 days, whereas others recommend casting all children with a history of acute injury, inability to walk or limp, no constitutional signs, and negative radiographs to avoid a delay in treatment.⁴²

Ankle and Foot

Ankle Fractures

Children do not sustain “sprains” and therefore this diagnosis should be used with caution, if at all.⁴³ Salter type I and II fractures can usually be managed conservatively with closed reduction followed by short-leg splint immobilization for 3 to 4 weeks. Nondisplaced distal fibular fractures may also be treated with a removable brace as return to functionality appears to be faster with this treatment approach. Salter types III, IV, and V will likely require operative intervention some time during their management. Pain over the distal fibula physis with a normal radiograph in a child should be managed as a Salter type I fracture.

The fracture pattern varies with age. An example of this age variation is the distal tibia fracture called a “Tillaux fracture,” which is unique to adolescents (Figs. 6–40). As skeletal maturity is achieved and growth plates are beginning to close, the medial distal tibial epiphysis closes prior to the lateral. This creates a fulcrum through which a Salter type III fracture may occur, just lateral to the point of fusion. Because of growth plate involvement and a potential need for open fixation, a prompt orthopedic consultation is indicated. Intra-articular injury is common. CT scans are useful in evaluating complex fracture patterns. Comparison views may help in difficult cases.

Talar dome fractures are far more common in children than in adults. An osteochondral fracture of the talar dome should be highly suspected when evaluating a child who presents with a nonhealing “ankle sprain” or recurrent effusions after an ankle sprain.

Tarsal Coalition

Tarsal coalition should be suspected in any child with a history of multiple ankle sprains who demonstrates subtalar stiffness on a physical examination. Tarsal coalition is the abnormal union of two or more bones in the hindfoot and midfoot. This condition may be congenital or acquired because of infection, trauma, or articular disorders. Patients typically present between 8 and 16 years of age. A family history of tarsal coalition may exist. Of all the coalition syndromes, talocalcaneal and calcaneonavicular are the most frequent type. The initial treatment is conservative, consisting of rest and a short-leg cast for 2 to 4 weeks, or the use of a well-molded orthotic and physical therapy. These patients should be referred for appropriate care and follow-up.

Pes Planus

Pes planus occurs quite commonly. The incidence of “flat feet” is approximately 7% to 22%. Most patients are asymptomatic. This condition generally does not cause any problems in children. Treatment of symptomatic flat feet with an accessory navicular consists of the use of an orthotic and an exercise program to strengthen the posterior tibial muscles and the peroneal tendons of the foot. Surgery is indicated in some cases.

Freiberg Disease

Freiberg disease involves collapse of the articular surface and subchondral bone of the second metatarsal, presumably from a vascular insult. Although this is most commonly seen in the second metatarsal, it can occur in the third metatarsal. Symptoms are pain and tenderness over the metatarsal head with swelling in this area on clinical examination. Radiographs confirm the diagnosis and treatment consists of decreased weight bearing to the area and a metatarsal pad or orthotic. Surgical excision of loose bodies because of fragmentation of the head is occasionally required.

Osteochondritis Dissecans of the Talus

Most of these lesions are in the middle third of the lateral border of the talus. Lesions are classified into four different stages.

• Stage 1: A small area of compression of subchondral bone.

• Stage 2: A partially detached osteochondral fragment.

• Stage 3: A completely detached osteochondral fragment remaining in the crater.

• Stage 4: A displaced osteochondral fragment.

Stage 1 and 2 lesions are treated without surgery using a cast, brace, or strap. Stage 3 medial lesions initially should be treated without surgery, but if symptoms persist, surgical excision and curettage is recommended. Stage 3 lateral lesions and all stage 4 lesions are treated surgically with removal of the lesion.

Sever's Disease

Sever’s disease, or calcaneal apophysitis, is a common entity occurring in patients between 9 and 11 years of age. The child presents with heel pain, particularly with running, and may use a tiptoe gait or limp. Radiographs are often not helpful; however, the patient is tender on palpation of the calcaneal apophysis. Treatment depends on the severity of the symptoms, the primary role being to rest the heel. In very symptomatic patients, a short-leg walking cast for 10 to 14 days is the treatment of choice.

Whenever there is delay in seeking treatment for an orthopedic injury, suspect the possibility of child abuse. If the history is inconsistent with the examination this should also be a sign that increases the suspicion of abuse.

Radiographic Evidence of Child Abuse

Fractures of the ribs or sternal area suggest child abuse. Any fractures seen in a child younger than 3 years should be suspect and particularly those seen in a child who is handicapped or premature. Metaphyseal fractures are also suspected as these fractures are rarely accidental and are due to traction of the extremity or a shearing force across the end of the bone (Fig. 6–41). Humerus fractures, particularly spiral fractures, in children younger than 3 years are strongly suggestive of abuse as spiral fractures occur in response to a torsional force. Scapular fractures are difficult to obtain and should also be suspected. Fractures of the femur, and particularly fractures of the distal femur, are highly suspicious injuries in the nonambulatory child. However, spiral femur fractures can occur accidentally in nonambulatory patients if the mechanism is appropriate.

The most critical features to look for when examining the radiograph of a potentially abused child are the following:

• Bilateral fractures

• Multiple fractures

• Metaphyseal fractures

• Rib fractures

• Scapular fractures

• Fractures of the outer end of the clavicle

• Fractures of different ages

• Skull fractures

Physicians treating children in the ED must have a basic knowledge of the stages of fracture healing that can be detected radiographically. Table 6–1 provides a general timetable of the various phases of fracture healing.⁴⁴ One must consider the data in this table as estimates only, because very young infants may exhibit an accelerated rate of repair.

Child abuse must be at the forefront of the emergency physician’s mind when examining any child, particularly those younger than 3 years with fractures.

The most common site for childhood malignant tumors is around the knee. One must be suspicious whenever there is unilateral knee pain without any associated trauma. Pathologic fractures are also suspect, particularly when they occur through weakened bone, which may be a bone cyst. A number of benign tumors occur in children as incidental findings; these include osteochondromas and fibrous cortical defects (FCDs).

Fibroxanthomas

Fibroxanthoma, nonossifying fibroma (NOF), FCD, and less commonly, benign fibrous histiocytoma, have all been used interchangeably in the radiology literature. However, NOF and FCD are considered to be two distinct lesions, with respect to size and natural history. Fibroxanthoma is the preferred term for the NOF lesion. FCDs are asymptomatic, small (<3 cm), eccentrically located, metaphyseal cortical defects. Most FCDs spontaneously disappear. However, some evolve and enlarge into fibroxanthomas.

Conversely, fibroxanthomas (>3 cm) are larger, eccentric, intramedullary lesions. They have a typical superficial scalloping pattern in the adjacent cortex (Fig. 6–42). Both lesions occur in the developing skeleton. Approximately 90% of cases of both lesions involve the tubular long bones with the most common sites being the femur (particularly the distal femur), the proximal and distal tibia, and the knee. FCDs occur in younger patients (4–8 years) and are typically incidental findings on radiographs that are obtained for other indications. The peak incidence for fibroxanthomas is 10 to 15 years.⁴⁵

Fibroxanthomas also are characteristically asymptomatic. In larger lesions, however, mild pain may occur secondary to radiographically undetected microfractures that can eventually lead to painful and radiographically evident pathologic fractures. With larger lesions, careful radiographic observation and decreased vigorous activity of the patient are recommended. Curettage and bone graft procedures are performed to prevent a pathologic fracture if the lesion becomes greater than 33 mm in diameter or involves greater than 50% of the transverse diameter of a critical weight-bearing bone. No specific treatment or intervention is required for FCDs.

Ewing Sarcoma

Ewing sarcoma, also known as peripheral primitive neuroectodermal tumors of bone, is a type of cancer usually found in children and young adults. The peak incidence is between ages 10 and 20. It is less common in children younger than 5 or in adults older than 30. Sarcomas can develop in any of the bones of the skeleton, but may also develop in the soft tissue near bones.

The most common symptom is pain in the bone in the area of the tumor. Some swelling may eventually be seen in the area and it may become tender to touch. Children may also present with a fever.

Ewing sarcomas are graded from 1 to 3. Grade 1 indicates a low-grade cancer and grades 2 to 3 indicate a high-grade cancer. High-grade tumors grow more quickly and are more likely to spread. Ewing sarcomas tend to be high-grade cancers.

Ewing sarcomas are staged as follows:

• Stage 1A: The cancer is a low-grade type and is found only within the hard coating of the bone.

• Stage 1B: A low-grade type of cancer extending outside the bone, into the soft-tissue space.

• Stage 2A: The cancer is a high-grade type and is found only within the hard coating of the bone.

• Stage 2B: A high-grade type of cancer extending outside the bone into the soft-tissue space.

• Stage 3: The cancer can be a low-grade or high-grade type and it is found either within the bone or outside the bone. The cancer has spread to other parts of the body, or to other bones not directly connected to the bone where the tumor started.

On plain films, a high-grade Ewing sarcoma is associated with significant periosteal reaction (Fig. 6–43). A sunburst appearance is used to describe the multiple interrupted linear areas of periosteal reaction that run perpendicular to the bone. When the lines of periosteal reaction run parallel to the bone, an “onionskin” appearance is used. Codman triangle refers to a short spicule of bone seen at the edge of the lesion where the periosteum is lifted off the cortex. CT delineates the extent of cortical involvement and provides some information about the amount of soft-tissue component. MRI reveals a large, highly vascular soft-tissue mass with extensive intramedullary spread.

Ewing sarcoma can occur in any bone in the body; however, the most common sites are the pelvis, thigh, lower leg, upper arm, and rib. Treatment consists of chemotherapy, radiotherapy, and possible limb-sparing surgery or amputation.

Osteoid Osteomas

Osteoid osteomas are benign bone-forming lesions typically found in children older than 5 years. The most common complaint is limp and localized pain. Radiographs reveal a small lucent lesion, which is less than 1 cm, surrounded by reactive sclerosis (Fig. 6–44).

Osteoid osteomas account for 12% of benign tumors and 3% of all tumors.^46,47 The most common skeletal sites are the metaphysis or diaphysis of long bones, which are affected in 73% of patients. The spine is affected in 10% to 14% of patients. The classic presentation includes focal skeletal bone pain, which worsens at night and is frequently relieved with small doses of anti-inflammatory medication. In most patients with spinal tumors, the pain increases with activity and also occurs at night. The site of involvement may be tender to touch or pressure. Constitutional symptoms are usually absent. The tumor can be percutaneously ablated by using radiofrequency, ethanol, laser, or thermocoagulation therapy under CT guidance.⁴⁷

Special thanks to Mariyah S. Shad for her assistance in the revision of this chapter.