Children are prone to injuries of the upper extremity due to their natural curiosity, being active in sports, and risk-taking behaviors. Boys incur more injuries than girls, with the highest incidence of injuries occurring between 10 and 18 years of age. This chapter reviews the diagnosis and management of injuries to the upper extremities and hands.

The clavicle is the most commonly fractured bone during delivery and is the fourth most commonly fractured bone in older children, accounting for approximately 15% of all pediatric fractures.¹ The clavicle is prone to fracture since the majority of its length resides subcutaneously, and functionally it distributes almost all forces from the upper extremity to the trunk. Fractures of the clavicle are categorized anatomically: medial third, middle third, and distal third.² The vast majority of injuries involve the area between the middle and distal third of the clavicle (>90%),³ and the majority are due to a direct fall onto the lateral aspect of the shoulder. Direct blows only account for about 10% of midshaft fractures, and an indirect mechanism, such as falling on an outstretched hand, accounts for less than 5% of these injuries.⁴ Young children can sustain incomplete injuries (green-stick or bowing fractures).

Fractures of the medial clavicle are rare in children. The medial clavicular epiphysis is the last growth plate to close, allowing physeal injuries to occur up to age 25. In contrast to adults, in whom sternoclavicular (SC) joint dislocations occur more frequently, children are most likely to experience a posteriorly displaced Salter–Harris type I or II fracture of the medial clavicular physis, with or without epiphyseal separation. It is important to distinguish a medial physeal injury from a posterior dislocation of the SC joint. Posterior dislocations of the SC joint, though very rare, are often associated with other complications such as brachial plexus injuries, pneumothorax, and neurovascular compromise from compression of mediastinal structures. Accurate determination of medial clavicular fractures is often difficult by plain film alone. If this injury is suspected, obtain a CT scan to determine the exact injury. Treatment is open reduction and stabilization of the SC and costoclavicular ligaments.^5,6

The most common mechanism for a midshaft clavicle fracture is a fall on the shoulder. If the fall is unwitnessed, the only history may be refusal to move the arm. The patient typically presents with decreased or painful movement of the arm. The child may have point tenderness over the middle of the clavicle, localized swelling, crepitus, and tenting of the overlying skin. Radiographs will confirm the suspected injury (Fig. 31-1). Obtain two views, with one view directed 30 degrees cephalad. Search for associated vascular injury in the presence of a displaced clavicle fracture, as laceration or compression of the subclavian vessels can occur with posterior displacement of the fracture fragments, prompting emergent orthopedic and vascular consultation.

During delivery, shoulder compression often results in fracture of the clavicle. The injury may be asymptomatic or present as pseudoparalysis (the infant will not move the arm, but hand and forearm movement is normal).⁷ Exuberant callus formation may call attention to the fracture a few weeks later. Remodeling occurs and results in a normal appearance of the bone in 6 to 12 months.

Most clavicle fractures heal well without complication, and reduction is rarely necessary in children less than 12 to 13 years of age. A displaced clavicular fracture in a skeletally immature patient has a low risk of malunion and excellent healing and remodeling potential. Although controversial, there is increasing evidence that operative fixation in skeletally mature adolescents with displaced clavicular fractures results in a lower nonunion rate and earlier return to normal function. Therefore, refer children in this older age group with displaced clavicular fractures to an orthopedic surgeon for management.^4,8 In addition, operative intervention is indicated in the presence of an open fracture, compromised skin, or vascular complication.

Place younger children in either a sling or a shoulder strap; manage older patients with a sling and swathe. Some children may find the sling more comfortable than the shoulder strap or clavicle brace. Adequate pain control is important, as these fractures can be very painful.⁹ Inform parents to expect a bump from callus formation to appear after about a month as the bone heals.

The distal epiphysis is not completely fused until the mid-twenties. Consequently, fractures of the lateral end of the clavicle usually result in a physeal separation of the distal clavicle rather than a true acromioclavicular (AC) separation, particularly in children <16 years of age. The thick periosteum forms a protective sleeve around the distal clavicle and the acromion and also serves as a point of attachment for the coracoclavicular (CC) ligaments. Since the periosteum is weaker than the attachments of the ligaments, when fractures occur, the clavicle is displaced through a disruption in the periosteum rather than by detachment of the CC ligaments. Although these fractures may mimic AC separation, they are more appropriately designated as “pseudodislocation.”² Following direct trauma, children will usually present with tenderness and swelling over the acromioclavicular joint. Radiographs will show an increased distance between the coracoid process and the clavicle. Weighted radiograph views are not recommended. Treat conservatively with the use of a sling and swathe or clavicle brace; surgery is rarely indicated.

Fractures of the scapula are very rare in children and infrequent in adolescents. They are often associated with high-energy injuries and the patient should be evaluated for more serious injuries.^10,11 In young children with minor or no history of trauma, or when noted as part of a skeletal survey as part of an abuse evaluation, scapular fractures have shown a statistically significant correlation with intracranial injury.¹²

A lateral scapular (trans-scapular) view, combined with an anteroposterior shoulder view, provides a two-plane assessment of the scapula. A lateral axillary view isolates the coracoid process and helps to delineate associated shoulder dislocations. Tangential oblique views may aid in the evaluation of small or subtle scapular body fractures.

The treatment of a scapular fracture is similar to a clavicle fracture.

The same forces that result in shoulder dislocation in adults usually cause displaced Salter–Harris type II fracture separation of the proximal humerus in young children. Less than 2% of shoulder dislocations occur in patients younger than 10 years, and 20% occur in patients aged 10 to 20 years. As with adults, anterior dislocations are much more common than posterior or inferior dislocations.^5,13

Inspection of the anteriorly dislocated shoulder reveals loss of the normally rounded contour, creating a squared-off appearance. The arm is held in slight abduction and external rotation, and the humeral head may be palpated anterior to the glenoid fossa. Include an anteroposterior (AP) view of the shoulder and either a true lateral scapular or a transaxillary view. Provide adequate analgesia and relaxation before attempting reduction with traction and countertraction, scapular manipulation, or external rotation techniques. Obtain postreduction radiographs to identify any occult fractures. After the reduction, immobilize the arm for 3 to 6 weeks and then begin rehabilitation therapy. Posterior shoulder dislocations are most often seen following seizures, electrical injuries, or after collisions in football lineman. The arm is held in adduction and internal rotation. The anterior shoulder appears abnormally flat, and the displaced humeral head may be palpable posteriorly. Obtain orthopedic consultation in all cases of posterior shoulder dislocation.

Both the axillary nerve and artery may be injured. Therefore, assess sensation over the deltoid muscle before and after reduction. Also assess distal pulse strength and examine the patient for the presence of a protruding axillary hematoma. Other complications include greater tuberosity fractures, damage to the glenoid labrum, Hill–Sachs deformity (a commonly associated compression fracture of the posterolateral humeral head), rotator cuff injury, and recurrent dislocation. Younger patients with instability have a much higher rate of recurrence than older adults, with the risk of recurrence up to 95% in patients who suffer their first dislocation under the age of 20. Refer patients in this age group to an orthopedic surgeon for further evaluation and care at an early stage.^4,10

PROXIMAL HUMERUS FRACTURE

The proximal humerus epiphyseal ossification center appears at 6 months of age. The greater tuberosity ossification center appears at 3 years and the lesser tuberosity center at 5 years. The physis closes at age 14 to 17 years in girls, and 16 to 18 years in boys. Nearly 80% of the longitudinal growth of the humerus takes place at the proximal humeral epiphysis. Accordingly, the potential for remodeling is great, leading to the majority of patients being treated nonoperatively.^14,15 The normal proximal humerus growth plate is often mistaken for a fracture. A comparison view of the uninjured shoulder may be helpful.

Salter–Harris type I and type II fractures of the proximal humerus are frequently encountered. Type I fractures and proximal metaphyseal injuries, including greenstick and torus fractures, typically occur in youngsters aged 5 to 11 years. Children of age 11 to 15 years suffer the majority of proximal humerus fractures, usually type II injuries. Most proximal humerus fractures are nondisplaced due to the presence of a strong periosteal sleeve. Salter–Harris fracture types III, IV, and V are rare in this region.⁵

Patients with proximal humerus fractures will have point tenderness at the fracture site with swelling and/or an obvious deformity. Include at least two views of the humerus at right angles to each other in radiographic evaluation. Include the distal clavicle and acromion in the film to look for an associated injury.

Most fractures of the proximal humerus heal well with only a sling and swathe. The decision for closed reduction or operative treatment depends on the age of the patient, the degree of angulation, open versus closed, and the amount of displacement. Current recommendations include continued nonoperative management for younger patients and consideration of operative intervention for the older patient (>10–13 years of age) with greater degrees of displacement and angulation.¹⁵

HUMERUS SHAFT FRACTURES

Most humeral shaft fractures are the result of a direct blow to the area. The degree of displacement depends on the location of the fracture and the surrounding muscle attachments, which may pull the fragments out of alignment. A torsional force from a fall or severe twist may result in a spiral diaphyseal fracture. Exclude nonaccidental trauma in children younger than 3 years with a spiral humerus fracture.

Midshaft fractures heal well even with angulation of up to 15 to 20 degrees and as much as 2 cm of overriding, due to bony remodeling and longitudinal overgrowth that occurs in response to the fracture. A sling and swathe should be applied to young children. A sugar-tong splint can be used for adolescents. Surgical consultation is needed for open fractures, ipsilateral forearm fracture (floating elbow), or persistent angulation greater than 20 to 30 degrees.¹⁶

Fractures involving the junction of the middle and distal thirds of the humerus may be associated with injury to the radial nerve. Assess motor and sensory functions initially and following any manipulation. Acute radial nerve palsy has an excellent long-term prognosis, with reports of 80% to 100% recovery of function without surgery.¹⁷

With injury to the elbow, radiographic interpretation is complicated by the presence of numerous epiphyses and ossification centers that appear and fuse at different but characteristic ages (Table 31-1). Matters are further complicated by the need for precise anatomic reduction of fracture fragments in order to avoid both early and late complications.

An adequate radiographic evaluation of the elbow consists of an AP view with the joint in extension and a true lateral view with the elbow flexed at a right angle. Frequently, adequate pain control is needed to flex the elbow fully for a true lateral radiograph and should be provided prior to radiographs. The anterior fat pad is located within the coronoid fossa and normally appears as a small lucency just anterior to the fossa on a true lateral radiograph of the elbow (Fig. 31-2). Joint space fluid collection may also cause the anterior fat pad to be pushed away from the joint and appear as a wind-blown sail—the “sail sign.” The posterior fat pad sits deep in the olecranon fossa and is not visible under normal circumstances. The presence of a posterior fat pad on a true lateral view of the elbow is always abnormal and suggests blood within the joint capsule. These abnormal fat pad signs are radiographic evidence of occult fracture of the distal humerus, proximal ulna, or radius (Fig. 31-3) and can only be detected with the elbow fully flexed at 90 degrees.

There are two reference lines that are useful in assessing elbow radiographs and help to identify occult injury. The anterior humeral line, drawn along the anterior cortex of the distal humerus on a true lateral view of the elbow, should normally intersect the middle third of the capitellum distally. Posterior displacement of the capitellum may be consistent with an otherwise radiographically occult supracondylar fracture. The radiocapitellar line is drawn down the axis of the proximal radius on the true lateral view of the elbow and should bisect the capitellum regardless of the degree of flexion or extension present. Failure to do so suggests the presence of an occult radial neck fracture or radial head dislocation. Any question about the anatomic relationships can be further investigated using comparison views of the uninjured elbow.

Supracondylar fractures account for 50% to 60% of all elbow fractures in children 3 to 10 years of age. The usual mechanism of injury with supracondylar fractures of the distal humeral metaphysis is a fall onto an outstretched hand, causing violent hyperextension of the elbow. The olecranon process is forcibly thrust into the olecranon fossa, resulting in fracture with posterior displacement of the distal fragment. On examination, there will be pain, swelling, deformity, and functional impairment. A careful neurovascular examination is crucial to identify an associated injury (Table 31-2). Obtain an AP and lateral radiograph (Fig. 31-4). Oblique views may be useful to demonstrate occult fractures.¹⁸

Gartland distinguished three types of supracondylar fractures (Table 31-3).¹⁹ Recently, Leitch proposed the addition of a type IV fracture to the Gartland classification. Type IV fractures are unstable in both flexion and extension because of complete loss of a periosteal hinge.²⁰ Use of the anterior humeral line may be helpful in determining whether the fracture is a type I or II (Fig. 31-4). Supracondylar humerus fractures are associated with a high incidence of early neurovascular complications (Fig. 31-5). Although puncture or actual laceration of the brachial artery is rare, the vessel may be compressed or contused or may undergo vasospasm at the fracture site. Signs of significant distal ischemia such as pallor and cyanosis of the fingers, prolonged capillary refill, or absence of the radial pulse indicate the need for prompt reduction of the fracture. If the vascular status is not improved, then surgical exploration is indicated. Patients are at risk of developing a forearm compartment syndrome, especially those with an ipsilateral corresponding diaphyseal forearm fracture. Unrecognized, this will lead to Volkmann’s ischemic contracture and a nonfunctional hand and wrist. Forearm pain with passive flexion or extension of the fingers or distal paresthesias is an ominous early sign of compartment syndrome. Nerve impairment is reported to occur in as many as 11.3% of children with supracondylar fractures, but the prognosis for return of function is good. Anterior interosseous nerve injury is the most common nerve injured in extension-type supracondylar fractures, followed by median, radial, and ulnar nerve injuries.^20,21 A late complication of supracondylar humerus fractures is cubitus varus, a change in the carrying angle of the elbow.

The potential for significant complications with supracondylar humerus fractures mandates accurate diagnosis and urgent orthopedic consultation. Rotational and angular deformities must be meticulously reduced in order to preserve normal elbow function and prevent vascular compromise. Type I and some type II supracondylar fractures can be managed with casting but most type II and all type III and IV fractures require reduction and internal fixation in the operating room.²⁰ Many children are admitted for 12 to 24 hours of observation postoperatively so that the neurovascular status of the extremity can be reassessed frequently. Open reduction and internal fixation may be necessary, especially if the injury is more than 12 hours old.²²

Fractures involving the articular surface of the lateral condyle (capitellum) comprise 15% of all pediatric elbow fractures; however, they are missed more often than any other elbow fracture in children. The peak in incidence is at 6 years of age. The mechanism of injury is frequently unknown but often involves a fall on the outstretched arm with forearm supination or elbow flexion. Salter–Harris type IV fractures are common. Clinically, swelling and tenderness are most pronounced at the lateral elbow. The fracture fragment may become displaced and rotated, and the diagnosis is radiographically obvious if the ossified capitellum is notably displaced from the trochlea or radiocapitellar line. Radiographic assessment of displacement can be improved by obtaining an internal oblique view of the elbow. These fractures require aggressive intervention to prevent later complications such as nonunion, loss of elbow mobility, and growth arrest of the lateral condylar physis leading to cubitus valgus and tardy ulnar palsy. Management is usually operative in all but nondisplaced fractures (<2 mm).²³