Proximal humeral fractures in children

INTRODUCTION — Proximal humeral fractures represent fewer than 5 percent of all pediatric fractures [1,2]. These fractures may occur either through the physis (growth plate) or in the metaphysis. One of the most important features of humeral fractures is their ability to remodel. The majority of these fractures can be treated with a sling and swathe or with a shoulder immobilizer.

This review addresses proximal fractures of the humerus in children. Fractures of the midshaft and distal humerus, including supracondylar fractures, are presented separately. (See "Supracondylar humeral fractures in children" and "Epicondylar and transphyseal elbow fractures in children" and "Evaluation and management of condylar elbow fractures in children" and "Midshaft humeral fractures in children".)

PERTINENT ANATOMY — The humerus is the largest bone in the upper extremity. The proximal humerus articulates with the glenoid of the scapula to form the glenohumeral (shoulder) joint. The muscles and tendons of the rotator cuff, the acromion, and ligamentous attachments such as those between the coracoid process of the scapula and the acromion, serve to both stabilize the glenohumeral articulation and provide for a wide range of shoulder joint motion.

The pediatric humerus has distinctive structural features that influence fracture risk, fracture pattern, and the potential for healing [3,4]:

●Periosteum – In the humerus bone, a thick periosteal sleeve is present along the shaft which limits fracture displacement and promotes healing in proximal humeral fractures [5]. (See "General principles of fracture management: Fracture patterns and description in children", section on 'Fracture patterns'.)

●Growth plate (physis) – The proximal humeral growth plate accounts for about 80 percent of the growth of the entire bone (figure 1) [5]. It closes between 16 and 19 years of age (figure 2) [5]. For these reasons, the remodeling potential in the proximal humerus is extraordinary, allowing even the most displaced fractures to be treated conservatively. (See "General principles of fracture management: Fracture patterns and description in children", section on 'Physeal (growth plate)'.)

Physeal fractures of the proximal humerus may occur at any age, but they are more common in the adolescent population. Rapid growth during adolescence makes the physeal region relatively weak and susceptible to fracture. Before adolescence, most proximal humeral fractures occur at the metaphysis, although Salter-Harris type I injuries are seen occasionally (figure 3 and figure 4) [4].

●Nerve anatomy – Following a displaced proximal humeral fracture, the axillary nerve is at potential risk for injury. However, nerve injuries after proximal humeral fractures are exceedingly rare. When seen, the majority are neurapraxias, ie, temporary loss of nerve function (especially motor function) without anatomical nerve disruption.

MECHANISM OF INJURY

Neonates — Humeral fractures are the second most common birth injury after clavicle fractures. Neonatal humeral fractures result from rotation or hyperextension of the upper extremity during passage through the birth canal (figure 5) [4].

Children and adolescents — Fractures of the proximal humerus commonly occur due to a fall on an outstretched hand (FOOSH) or from a direct blow to the lateral aspect of the shoulder (figure 6) [3,6]. Stress fractures of the proximal humeral physis may also occur due to repetitive internal rotation of an abducted externally rotated shoulder while throwing a baseball [5,7].

Pathologic fracture — The humerus is a common location of bone cysts and other benign lesions [3,6-9]. A proximal humeral fracture that occurs with a history of minimal trauma may suggest a pathologic fracture through such a lesion.

Child abuse — A mechanism inconsistent with the injury and/or a fracture in an otherwise healthy child younger than two years of age with normal bone density by radiograph should raise concern for child abuse [10]. Metaphyseal corner fractures, also known as bucket handle fractures, at the proximal humeral physis may occur when the extremity is pulled or twisted forcibly, or the child is shaken (image 1). These fractures are highly correlated with child abuse. (See "Orthopedic aspects of child abuse", section on 'Humeral fractures'.)

Other injuries concerning for child abuse are frequently present (table 1 and table 2). (See "Physical child abuse: Recognition".)

PHYSICAL FINDINGS

Proximal humerus fractures — The child with a proximal humeral fracture typically presents with a history of trauma, severe shoulder pain, and marked pain on arm movement. For nondisplaced proximal humeral fractures, the physical findings may be limited to tenderness and mild swelling [6,11]. For displaced fractures, significant anterior swelling and altered shoulder appearance relative to the unaffected side is often present, and the arm is usually shortened and held in extension [6].

Detailed neurovascular assessment is important to identify axillary nerve deficit. This injury presents with decreased sensation over the lateral shoulder and loss of deltoid muscle function (shoulder abduction).

Neonatal fracture — In addition to arm swelling or deformity, the neonate with a proximal humeral fracture may present with irritability when held and may refuse to move the upper extremity ("pseudoparalysis") [7].

Associated findings — After major trauma, proximal humeral fractures may be associated with shoulder dislocation or life-threatening injuries of the neck, head, and thorax. If present, these injuries should take priority over management of the humeral fracture during stabilization of the patient. (See "Trauma management: Approach to the unstable child".)

RADIOGRAPHIC FINDINGS

Proximal humeral fractures — Routine AP and axillary lateral views of the humerus are generally sufficient to diagnose a proximal humeral fracture. If the injured child is tender at the physis, the treating physician should suspect a Salter-Harris I fracture, even in the presence of normal radiographs [4]. (See "General principles of fracture management: Fracture patterns and description in children", section on 'Physeal fracture description'.)

If clinical concern for a shoulder injury is present, a complete three view shoulder series should also be obtained. This series includes an anterior-posterior view of the glenohumeral joint, an axillary view, and a scapular Y view. The last two views are necessary to assess the glenohumeral relationship and to exclude any dislocation or subluxation [3].

Comparison views of the unaffected humerus may be helpful to determine if widening of the physis is present. Variations in the epiphyseal line of the proximal humerus are normal findings and should not be confused with a fracture [5].

Neonatal fractures — It is challenging to evaluate a young infant's shoulder and proximal humerus radiographically because the humeral head is primarily cartilaginous and, thus, not seen on plain films until approximately six months of age [3]. Plain films alone may be inadequate to distinguish between a physeal fracture and a dislocation. In this circumstance, ultrasonography or MRI imaging is often needed to diagnose and fully characterize the fracture [3,6].

Proximal humeral fracture description — Proximal humeral fractures involving the physis are classified using the Salter-Harris classification system (figure 4). Physeal fractures of the proximal humerus are most commonly seen in adolescents, in whom rapid growth leads to relative weakness of the physis (image 2). Salter-Harris II fractures are the most common pattern in this age group. Younger children most commonly suffer metaphyseal fractures (image 3), although Salter-Harris I fractures may occasionally occur. (See "General principles of fracture management: Fracture patterns and description in children", section on 'Physeal fracture description'.)

Metaphyseal proximal humeral fractures are classified in a descriptive manner by their anatomic location, fracture pattern, displacement, and angulation [6,8].

INITIAL TREATMENT — For children with proximal humeral fractures, initial treatment consists of pain management, immobilization, and radiographic evaluation [2].

Analgesia — Intranasal fentanyl or intravenous fentanyl or morphine is most appropriate for initial pain control in patients with severe pain and should be given prior to radiographic evaluation. Oral analgesia (eg, ibuprofen 10 mg/kg) may suffice for patients who have mild or moderate pain. In most circumstances, pain relief will result in an improved ability to assess and obtain necessary radiographs in the apprehensive child.

Immobilization — Immobilization in a sling and swathe (figure 7) or shoulder immobilizer, depending on the child's age, enhances patient comfort and prevents further fracture displacement. Neurovascular status should be checked before and after immobilization. (See 'Definitive care' below.)

Orthopedic consultation — Prompt orthopedic consultation should be obtained in the following circumstances:

●Proximal humeral fracture associated with shoulder dislocation

●Intraarticular (Salter-Harris IV) fracture

●Completely displaced fracture in children over 12 years of age (image 4)

●Fracture with neurovascular compromise (eg, axillary nerve injury)

●Open fracture (rare in the proximal humerus)

●Fracture with evidence of compartment syndrome (rare in the proximal humerus)

Child protection — Diagnosis of a humeral fracture in a child with no plausible mechanism of injury and/or if the child is younger than two years of age should prompt involvement of an experienced child protection team (eg, social worker, nurse, physician with more extensive experience in the management of child abuse), if available. In many parts of the world (including the US, UK, and Australia), a mandatory report to appropriate governmental authorities is also required. (See 'Child abuse' above and "Child abuse: Social and medicolegal issues", section on 'Reporting suspected abuse'.)

In addition, for all children with humeral fractures and clinician concern for child abuse, the medical care team should ensure that a complete evaluation for child abuse is performed as described separately and work with local Child Protective Services to ensure the safety of other children in the home. (See "Physical child abuse: Diagnostic evaluation and management".)

DEFINITIVE CARE — Treatment of proximal humeral fractures varies by patient age.

Infants — For infants, a sling and swathe (with the arm wrapped to the torso by an Ace wrap) is sufficient immobilization for a proximal humeral fracture. Because of the early healing potential and the palpable callous mass that is typically formed, immobilization may be limited to four weeks [6]. Follow-up examinations should be done to exclude a brachial plexus injury [3,12].

Children and adolescents — Either sling immobilization or a shoulder immobilizer may be used for minimally displaced (eg, displacement less than one-third of shaft width and less than 20 degrees of angulation) proximal humeral fractures in older children and adolescents [13,14]. Gentle pendulum exercises may be started between two and four weeks post-injury, and an active range of motion may be started between four and six weeks. Most patients can resume overhead activities after four to six weeks and often have normal or near-normal function two months from the date of injury [3,6,7].

Individual variation in duration of immobilization and progress in return to normal activity may reflect the patient's healing capacity and injury severity. Orthopedic follow-up is recommended during the course of the injury to confirm appropriate management and clinical progress.

In most cases, even markedly displaced proximal humeral fractures in children ≤12 years of age can be treated with a U-slab, sling, and swathe (figure 8) [13]. In this young patient population, the significant remodeling potential of the proximal humerus allows a markedly displaced fracture to heal and remodel to a normal-appearing, fully functional shoulder [6,15,16]. For comfort, improvement in length, and cosmesis, the child may receive a hanging arm cast, which fatigues the muscles spanning the fracture and often improves the deformity. Children frequently prefer to sleep upright in a recliner for the first 7 to 10 days.

For older children (≥12 years of age) with marked displacement, operative treatment is recommended [13,14].

Open treatment is reserved for those patients who have displaced intra-articular fractures or those with neurovascular compromise, which is extremely rare in the pediatric patient population [6].

FOLLOW-UP CARE — Patients with proximal humeral fractures should be discharged with instructions to follow-up with an orthopedic surgeon in 7 to 10 days. Infants are maintained in a sling and swathe for three to four weeks. Either sling immobilization or a shoulder immobilizer should be used for proximal humeral fractures in older children and adolescents who do not undergo surgical repair.

Children who have received operative care (closed reduction with percutaneous pinning or open reduction with internal fixation or fragment removal) should be admitted for 24 to 48 hour observation of neurovascular status and soft tissue compartments. Once discharged, these patients are followed closely and may require weekly orthopedic evaluation with radiographs to determine the optimal timing for subsequent hardware removal.

Most nerve deficits associated with humeral fractures are neurapraxic injuries that resolve with observation.

COMPLICATIONS — Complications of proximal humeral fractures are rare in children. The most common complication is a mild shortening of the humerus, secondary to physeal damage and growth retardation, which may occur more frequently in older children [3,17]. This limb length discrepancy is not usually associated with functional disability and often is not clinically apparent [6].

Radiographic malunion of the fracture is also a reported complication, but is rarely associated with functional limitation [18].

In neonates, brachial plexus palsy may occur as an additional complication of birth trauma [19]. Infants with a proximal humeral fracture should be followed closely with serial neurologic examinations to identify this potentially significant injury. In general, neurovascular injury resulting from proximal humeral fractures is otherwise rare in the pediatric population.

OUTCOMES — Complications of proximal humeral fractures are uncommon in the pediatric population. The prognosis for healing and remodeling is excellent, especially in young patients [8].

ADDITIONAL INFORMATION — Several UpToDate topics provide additional information about fractures, including the physiology of fracture healing, how to describe radiographs of fractures to consultants, acute and definitive fracture care (including how to make a cast), and the complications associated with fractures. These topics can be accessed using the links below:

●(See "General principles of fracture management: Bone healing and fracture description".)

●(See "General principles of fracture management: Fracture patterns and description in children".)

●(See "General principles of acute fracture management".)

●(See "General principles of definitive fracture management".)

●(See "General principles of fracture management: Early and late complications".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: General management of pediatric fractures" and "Society guideline links: Upper extremity, thoracic, and facial fractures in children" and "Society guideline links: Acute pain management".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topic (see "Patient education: How to care for your child's cast (The Basics)")

●Beyond the Basics topic (see "Patient education: Cast and splint care (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Fractures of the proximal humerus are uncommon childhood injuries that typically occur from a fall on an outstretched hand or a direct blow. A growth plate (physis) is present in the proximal humerus which closes between 16 and 19 years of age (figure 1). Growth plates are susceptible to fracture and these physeal injuries are more common during times of rapid growth, such as adolescence (figure 4). (See 'Pertinent anatomy' above and 'Mechanism of injury' above.)

●A humeral fracture which occurs with a history of minimal trauma may suggest a pathological fracture or an intentional injury (child abuse). (See 'Pathologic fracture' above and 'Child abuse' above and 'Child protection' above.)

●The child with a proximal humeral fracture typically presents with a history of trauma, severe shoulder pain, and marked pain on arm movement. For nondisplaced proximal humeral fractures, the physical findings may be limited to tenderness and mild swelling. For displaced fractures, significant anterior swelling and altered shoulder appearance relative to the unaffected side is typically present, and the arm is often shortened and held in extension. (See 'Physical findings' above.)

●Detailed neurovascular assessment is important to identify axillary nerve deficit manifest by decreased sensation over the lateral shoulder and loss of deltoid muscle function (shoulder abduction). (See 'Physical findings' above.)

●If the injured child is tender at the physis, the treating physician should suspect a fracture and not a sprain, even in the presence of normal radiographs. (See 'Proximal humerus fractures' above.)

●Proximal humeral fractures involving the physis are classified using the Salter-Harris classification system (figure 4). Physeal fractures of the proximal humerus are most commonly seen in adolescents, in whom rapid growth leads to relative weakness of the physis (image 2). Salter-Harris II fractures are the most common pattern seen in this age group. Younger children most commonly suffer metaphyseal fractures (image 3). (See 'Proximal humeral fracture description' above and 'Radiographic findings' above and "General principles of fracture management: Fracture patterns and description in children", section on 'Physeal (growth plate)'.)

●Proximal humeral fractures in infants are treated with simple immobilization in a sling and swathe (figure 7). (See 'Infants' above.)

●Children with minimally displaced fractures may be immobilized with a sling and swathe (figure 7) or shoulder immobilizer. (See 'Children and adolescents' above.)

●Displaced proximal humeral fractures typically are treated initially with a U-slab splint, sling, and swathe in children and adolescents (figure 8), depending on the child's age, degree of angulation, and displacement. (See 'Children and adolescents' above.)

●The emergency clinician should obtain prompt orthopedic consultation in selected circumstances. (See 'Orthopedic consultation' above.)

●The prognosis for full recovery without functional limitation after a proximal humeral fracture is excellent, especially in young patients. (See 'Outcomes' above and 'Complications' above.)