Elbow fractures account for approximately 5% to

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1 Common Pediatric Elbow Fractures Erin S. Hart Allison Turner Maurice Albright Brian E. Grottkau Fractures of the elbow are a very common injury in children. The most common mechanism of injury is a fall on an outstretched upper extremity during play. Ranging in complexity from low-energy nondisplaced occult fractures to highenergy fractures with associated severe soft-tissue and neurovascular injuries, elbow fractures are a challenging problem for all pediatric healthcare providers. Because of the wide spectrum of fracture severity and associated bony and ligamentous injury, a very diverse spectrum of treatment modalities is necessary for optimal results. Management is based on fracture pattern, patient age and bone quality, extent of soft tissue damage, functional needs of the patient, and the presence of associated injuries. This article will give a brief overview of 4 common pediatric fractures, current treatment algorithms, and frequent complications associated with these injuries. Elbow fractures account for approximately 5% to 10% of all fractures in children. It is often helpful to address elbow fractures from an anatomic perspective, as each specific fracture has its own unique challenges in diagnosis and treatment. The elbow joint is a complex articulation of three bones (humerus, radius, and ulna) that allows motion in all three planes (see Figure 1). The radial-humeral articulation allows pronation and supination of the forearm, and the ulnarhumeral articulation allows flexion and extension of the elbow (Herring, 2002). It is often very difficult to distinguish fractures from the six normal secondary ossification centers in the elbow. The six ossification centers actually develop in a systematic, fairly predictable fashion in children. The mnemonic CRMTOL is helpful in remembering the progression of the radiographic appearance of the ossification centers about the elbow (see Table 1). This stands for Capitellum, Radial head, Medial epicondyle, Trochlea, Olecranon, and Lateral epicondyle (Waters, 2006). In general, the capitellum appears radiographically at around 2 years of age and the remaining ossification centers appear sequentially every 2 years. The appearance of the various ossification centers might vary slightly with girls often maturing earlier than boys. However, the overall sequence generally stays the same. If it is difficult to distinguish a normal secondary center of ossification from a fracture, it may be useful to obtain comparison radiographs (x-rays) from the contralateral elbow. The most common elbow fractures in children include supracondylar humerus (SCH) fractures, lateral condyle fractures, radial neck fractures, and medial epi- condyle fractures. Because 80% of the longitudinal growth in the arm occurs proximally (proximal humerus), only appositional growth occurs at the elbow. This limits the ability for elbow fractures to completely remodel and therefore makes anatomic reductions necessary even in young skeletally immature individuals (Do & Herrera-Soto, 2003). Supracondylar Humerus Fracture Supracondylar humerus fractures are the most common elbow injury in children (Kasser & Beatty, 2006). They account for approximately 50% to 70% of all elbow fractures in children (Farnsworth, Silva, & Mubarak, 1998). This injury occurs most often in boys between the ages of 4 and 7 and most frequently occurs after a fall on an outstretched upper extremity. Supracondylar humerus fractures are usually divided into extension and flexion types with extension types being far more common (~97% 99%). Clinical findings include pain, elbow swelling or effusion, deformity, and bruising/ecchymosis (see Figure 2). It is usual to have a fairly rapid onset of significant swelling with this type of elbow fracture. Providers should note the presence of skin puckering that usually results from the fracture fragment piercing the brachialis muscle and is a sign of considerable soft tissue damage. Any bleeding or break in the skin associated with the SCH fracture should be considered an open fracture and treated accordingly. It is important to assess neurovascular status (both sensory and motor function) thoroughly in every patient with a suspected or known elbow fracture. It is also important to evaluate the entire extremity, as forearm fractures can occur in association with SCH fractures and can significantly increase the risk Erin S. Hart, MS, RN, CPNP, Massachusetts General Hospital for Children, Department of Orthopaedic Surgery, Yawkey Center for Outpatient Care, Boston, MA. Alison Turner, MS, RN, CPNP, Massachusetts General Hospital for Children, Department of Orthopaedic Surgery, Yawkey Center for Outpatient Care, Boston, MA. Maurice Albright, MD, Massachusetts General Hospital for Children, Department of Orthopaedic Surgery, Yawkey Center for Outpatient Care, Boston, MA. Brian E. Grottkau, MD, Massachusetts General Hospital for Children, Department of Orthopaedic Surgery, Yawkey Center for Outpatient Care, Boston, MA. The authors have disclosed that they have no financial interests to any commercial company related to this educational activity DOI: /NOR.0b013e c6 Orthopaedic Nursing January/February 2011 Volume 30 Number 1 11

2 FIGURE 1. Elbow joint anatomy showing humerus, radius, and ulna bone. of compartment syndrome (Blakemore, Cooperman, Thompson, Wathey, & Ballock, 2000). Most nerve injuries occur secondary to contusion and traction ischemia at the displaced fracture (Waters, 2006). Unless the patient presents with an ischemic hand, an open fracture or significant skin tenting, the upper extremity should be immobilized as it lies with a simple splint (posterior long arm or sugar tong splint), while awaiting definitive treatment (Herring, 2002). If the distal extremity is ischemic, a gentle attempt to better align the fracture fragments is done to restore circulation to the hand. All patients should be kept from having food or drink by mouth until a definitive treatment plan has been outlined. CLASSIFICATION The Gartland classification system of SCH fractures is generally the most commonly accepted and used system (see Table 2). Type I fractures are nondisplaced and are generally treated with a course of short-term immobilization (~3- to 6-week long-arm cast). Type II fractures are displaced but often have an intact hinged posterior TABLE 1. OSSIFICATION CENTERS IN THE PEDIATRIC ELBOW CRMTOL C: Capitellum R: Radial head M: Medial epicondyle T: Trochlea O: Olecranon L: Lateral epicondyle FIGURE 2. Large elbow joint effusion/swelling status post supracondylar humerus fracture. cortex. Type III SCH fractures are completely displaced (no cortical contact between fragments) and have the highest rate of neurovascular compromise (see Figures 3A and B; Waters, 2006). SCH Type II and III are generally treated with closed or open reduction and percutaneous pinning. Simanovsky, Lamdon, Mosheiff, and Simanovsky, (2007) demonstrated the importance of reduction when treating displaced SCH fractures. Their study found that patients who healed with some degree of extension developed limited elbow flexion. Reductions are usually done in the operating room with the patient under general anesthesia. Malunions generally occur when the reduction is attempted in the emergency department or clinic, when the initial angulation is not recognized, and when the cast is applied without any reduction attempt (Simanovsky et al., 2007). Radiographs of nondisplaced (Type I) SCH fractures often show normal results or may have subtle signs such TABLE 2. GARTLAND CLASSIFICATION SYSTEM FOR SUPRACONDYLAR HUMERUS FRACTURES Type I nondisplaced, treated with immobilization in long arm cast Type II displaced with posterior hinge, usually treated with closed reduction and percutaneous pinning Type III completely displaced (no cortical contact between fracture fragments), treated with closed/open reduction and percutaneous pinning 12 Orthopaedic Nursing January/February 2011 Volume 30 Number 1

3 NOR qxd 1/7/11 5:01 AM Page 13 geons currently recommend reduction and pinning for any displaced SCH fracture. The treatment will vary by fracture type and pattern, but the goal remains the same which is to maintain alignment of the fracture to allow full functional recovery (Omid, Choi, & Skaggs, 2008). Although much debate exists over the placement of percutaneous pins, two lateral pins are generally used for most Type II and Type III SCH fractures. Kocher, Kasser, and Waters (2007) studied the efficacy of lateral entry pin fixation with that of crossed (medial and lateral) pins for completely displaced (Type III) SCH fractures. A prospective randomized trial was performed with 52 patients. There was no major loss of reduction in either group and no difference in the rate of minor loss of reduction. There was also no statistical difference between groups radiographically or clinically (range of motion, carrying angle, return to function, complication rate). Many other studies, however, have shown an increased risk of ulnar nerve injury associated with medial pin placement (Brauer, Lee, Bae, Waters, & Kocher, 2007; Skaggs et al., 2001). In their systemic review, Brauer et al. (2007) found that patients requiring medial pinning for SCH fractures were 5.04 times more likely to have ulnar nerve injury. Similarly, Skaggs, Cluck, Mostofi, Flynn, and Kay (2001) found a 7% incidence of iatrogenic ulnar nerve injury when crossed Kirschner wires were used and there was no difference in the stability of the fracture when compared with lateral pins alone. Following closed or open reduction, the fracture is usually held with two or three Kirscher wires with the elbow in approximately of flexion (see Figure 4; FIGURE 3. Anteroposterior/Lateral x-rays of Type III displaced supracondylar humerus fracture. as a small joint effusion or elevation of the anterior or posterior fat pad. Positive anterior and posterior fat pad sign generally indicates a joint effusion/hematoma and is generally treated as a nondisplaced or occult fracture. Approximately 70% of the time, posterior fat pads suggest an occult fracture of the supracondylar region, radial neck, or olecranon (Skaggs & Mirzayan, 1999). Type I SCH fractures are generally treated with immobilization in a long-arm cast with the elbow in approximately of flexion. Flexing the elbow more than 100 has been shown to increase the risk of ischemia and compartment syndrome (Battaglia, Armstrong, & Schwend, 2002). These fractures are very stable because the periosteum is intact circumferentially. The differentiation between Type I and Type II SCH fractures is often made by evaluating the position of the capitellum (distal end of the humerus) relative to the anterior humeral line. In Type II fractures, the capitellum falls posterior to the anterior humeral line. Occasionally, obtaining a contralateral elbow x-ray film can be useful to detect subtle injuries. TREATMENT OF TYPE II AND III SCH FRACTURES The treatment of Type II SCH fractures is more controversial, although most pediatric orthopaedic sur- FIGURE 4. Anteroposterior x-ray of left elbow status post closed reduction and percutaneous pinning with two Kirscher wires. Orthopaedic Nursing January/February 2011 Volume 30 Number 1 13

4 Abzug & Kozin, 2008). The cast and/or splint is usually removed after 3 4 weeks, and the pins are removed in a clinic setting. Activities are usually restricted until full range of motion and strength are achieved (generally 6 8 weeks after fracture). Complications Complications of SCH fractures include loss of reduction, neurovascular injury, pin track infection, malunion, nonunion, compartment syndrome, Volkmann s ischemia, and decreased range of motion (Abzug & Kozin, 2008). Vascular injury occurs in approximately 2.5% of Type III SCH fractures and neural impairment can occur in 17% (Gosens & Bongers, 2003). The most commonly injured nerve following SCH fractures is the anterior interosseous branch of the median nerve (Lyons, Quinn, & Stanitski, 2000). Anterior interosseous nerve palsy is probably underreported because it is not associated with a sensory loss. Nearly all nerve injuries associated with SCH fractures recover spontaneously and require no treatment other than close monitoring. If normal function has not returned within 8 to 12 weeks, it may be useful to obtain nerve conduction and electromyographic studies for further evaluation (Herring, 2002). Battle and Carmichael (2007) evaluated the infection rate with the use of smooth Kirschnew wires in 202 patients presenting with a SCH fracture. They found an overall infection rate of 2% and that the infection rate did not correlate to the type of fracture or the length of treatment (Simanovsky et al., 2007). Malunion resulting in cubitus varus or cubitus valgus are also known complications of SCH fractures. Although functional deficits are rare with these deformities, there may be slightly limited range of motion and unacceptable cosmesis. Because there is limited potential for remodeling in the distal humerus, the best treatment of malunion deformities is early avoidance. Lateral Condyle Fractures Lateral condyle fractures of the distal humerus involve the both physis and the articular surface. The diagnosis of condylar fractures can be very difficult in children because much of the elbow remains cartilaginous and is often not visualized well on plain radiographs (Horn, Herman, Crisci, Pizzutillo, & MacEwen, 2002). They are the second most common elbow fracture in children (~10% 20% of all elbow fractures) and can be difficult to diagnose and treat. This type of fracture commonly occurs in children between the ages of 4 and 10 with a peak incidence around 5 to 6 years of age (Abzug & Kozin, 2008). The diagnosis of lateral condyle fractures in children may be quite obvious or frustratingly subtle. Most lateral condyle fractures require surgical reduction and stabilization. Similar to SCH fractures, lateral condyle fractures are classified by the degree of displacement. Unlike SCH fractures, however, lateral condyle fractures often require open rather than closed reduction and percutaneous pinning. The most commonly used classification system for lateral condyle fractures is that of Milch (1964), which differentiates between Type 1, in which the fracture line traverses the capitellum and falls lateral to the trochlea, and Type 2, in which the fracture line extends further medially to the trochlear groove. A newer and slightly simpler classification system for lateral condyle fractures is based solely on the degree of displacement. Type 1 fractures are nondisplaced, Type 2 fractures are displaced less than 2 mm, and Type 3 fractures are displaced and malrotated (Rutherford, 1985). The difficulty in treating lateral condyle fractures is in differentiating stable nondisplaced fractures from potentially unstable, minimally displaced fractures (Mirsky, Karas, & Weiner, 1997). The treatment of lateral condyle fractures depends on the degree of fracture displacement. There is a slight controversy regarding the treatment of nondisplaced and minimally displaced lateral condyle fractures. Most pediatric orthopaedic surgeons will choose operative treatment of lateral condyle fractures displaced more than 2 mm (see Figure 5). Displaced lateral condyle fractures are generally treated with an open reduction and pinning (see Figure 6). Open reduction is usually performed through an anterior lateral approach in children. The blood supply of the lateral humeral condyle arises from the posterior soft tissues of the distal fragment, so it is important that there be minimal dissection of the posterior soft tissues (Herring, 2002). Smooth Kirshner percutaneous pins are generally used for fracture fixation and the elbow is immobilized for 4 6 weeks postoperatively. The most common complications from lateral condyle fractures include delayed union, nonunion, malunion, cubitus varus, stiffness, and avascular necrosis of the lateral condyle (Launay, Leet, Jacopin, Luc-Jouvre, Bollini, & Sponseller, 2004). The most frequent problematic complication of lateral condyle fractures is delayed union or nonunion (Herring, 2002). The difficulty in achieving union of lateral condyle fractures can be explained by the fact that it is an intra-articular fracture (constant exposure to synovial fluid), and this area of FIGURE 5. Anteroposterior x-ray of left elbow status post percutaneous pinning for Type II lateral condyle fracture. 14 Orthopaedic Nursing January/February 2011 Volume 30 Number 1

5 NOR qxd 1/7/11 5:01 AM Page 15 FIGURE 6. Status-post open reduction and percutaneous pin- FIGURE 8. Anteroposterior/Lateral x-ray of displaced medial epicondyle fracture. ning for displaced lateral condyle fracture. bone has a relatively poor blood supply. The stiffness associated with lateral condyle fractures is likely due to the articular nature of the fracture and the fact that a longer period of immobilization is often required (Do & Herrera-Soto, 2003). The incidence of stiffness, however, has been decreasing significantly recently because of improved stability associated with newer methods of fixation that allows for shorter periods of immobilization. Radial Neck Fractures Radial neck fractures comprise approximately 6% of pediatric elbow fractures. Similar to all pediatric elbow fractures, the treatment of radial neck fractures is based on the degree of displacement. In children, the cartilaginous radial head is resistant to fracture, and therefore radial neck fractures are much more common than radial head fractures (Waters, 2006; see Figure 7). Radial neck fractures often have subtle clinical and radiographic findings. There may be mild local swelling, tenderness, and ecchymosis over the radial neck. Although flexion and extension of the elbow will often be limited, pain with supination and pronation is actually much more common in radial neck fractures. The mechanism of injury is typically a fall on an outstretched hand with the elbow in extension and valgus. Radial neck fractures can also be seen in young patients with an associated elbow dislocation. There is controversy regarding the acceptable alignment of a radial neck fracture; however, most pediatric orthopaedic surgeons agree that up to 30 of malalignment and one-third displacement may be acceptable in radial neck fractures (Waters, 2006). Closed reduction is FIGURE 9. Anteroposterior/Lateral x-ray of elbow s/p open refigure 7. Anteroposterior x-ray of displaced radial neck fracture. duction and internal fixation of displaced medial epicondyle fracture. Orthopaedic Nursing January/February 2011 Volume 30 Number 1 15

6 attempted first and is usually successful for most displaced radial neck fractures. If closed reduction is inadequate, an open reduction through a posterolateral approach with as little dissection as possible is done. Fixation is generally achieved with smooth K-wires placed percutaneously from distal to proximal across the fracture site. Complications associated with radial neck fractures included malunion, stiffness, nonunion, radial head overgrowth, avascular necrosis, and early joint degeneration. Loss of motion is the most common and problematic complication following radial neck fractures. Rotation of the forearm is affected with loss of pronation greater than supination. Severely displaced and late presenting fractures requiring open reduction and internal fixation or pinning are more likely to develop stiffness and avascular necrosis (Milbrandt & Copley, 2004). Medial Epicondyle Fractures Medial epicondyle fractures account for approximately 10% of all pediatric elbow fractures and occur most commonly between the ages of 7 and 15 years (Herring, 2002). Approximately 50% to 60% of all medial epicondyle fractures are associated with a concurrent elbow dislocation. The mechanism of injury is usually excessive valgus stress which is why this fracture is often seen in baseball pitchers (significant valgus stress on their elbow with pitching). The operative treatment of medial epicondyle fractures is somewhat controversial. Nondisplaced and minimally displaced ( 5 mm) fractures are usually treated conservatively with immobilization/casting for a period of 4 6 weeks. Because this fracture is also frequently associated with stiffness, the period of immobilization in a cast should be minimized as much as possible (3 4 weeks). Fractures displaced more than 5 mm will usually require open reduction and internal fixation (see Figure 8; Do & Herrera-Soto, 2003). Serious overhead athletes require special consideration with this type of fracture. Even minimally displaced medial epicondyle fractures can lead to valgus instability and decreased throwing velocity. Anatomic reduction via open reduction and internal fixation is generally recommended in these patients (see Figure 9). Most surgeons prefer open reduction and fixation (often with cannulated screw fixation) over closed reduction and percutaneous pinning to ensure that the ulnar nerve is not damaged (Herring, 2002). Complications from medial epicondyle fractures include stiffness, ulnar nerve injury, nonunion, and malunion (Hines, Herndon, & Evans, 1987). Stiffness is the most common complication associated with medial epicondyle fractures. It is best avoided by decreased immobilization time and early gentle range-of-motion exercises. Conclusion Elbow fractures are a common injury in children and require a thorough understanding of the various fracture types and potential treatments available. It is usually best to address elbow fractures from an anatomic perspective as each specific fracture has its own unique challenges in diagnosis, management, and potential complications. Most children who sustain an elbow fracture can be expected to have a full functional recovery with appropriate treatment. Because of the numerous potential pitfalls and complications associated with pediatric elbow fractures, it is important to respond in a timely manner with appropriate vigilance and technical skill. REFERENCES Abzug, J. M., & Kozin, S. H. (2008). Pediatric upper extremity trauma. Pediatric upper extremity trauma. Current Orthopaedic Practice, 19(5), Battaglia, T. C., Armstrong, D. G., & Schwend, R. M. (2002). Factors affecting forearm compartment pressures in children with supracondylar fractures of the humerus. Journal of Pediatric Orthopaedics, 22, Battle, J., & Carmichael, K. D. (2007). Incidence of pin track infections in children s fractures treated with Kirschner wire fixation. Journal of Pediatric Orthopaedics, 27, Blakemore, L. C., Cooperman, D. R., Thompson, G. H., Wathey, C., & Ballock, T. R. (2000). Compartment syndrome in ipsilateral humerus and forearm fractures in children. Clinical Orthopaedics and Related Research, 376, Brauer, C., Lee, B., Bae, D., Waters, P. M., & Kocher, M. S. (2007). A systemic review of medial and lateral entry pinning vs. lateral entry pinning for supracondylar fractures of the humerus. Journal of Pediatric Orthopaedics, 27, Do, T, & Herrera-Soto, J. (2003). Elbow injuries in children. Current Opinion in Orthopaedics, 15, Farnsworth, C. L., Silva, P. D., & Mubarak, S. J. (1998). Etiology of supracondylar humerus fractures. Journal of Pediatric Orthopaedics, 18, Gosens, T., & Bongers, K. J. (2003). Neurovascular complications and functional outcome in displaced supracondylar fractures of the humerus in children. Injury, 34(4), Herring, J. A. (2002). Upper extremity injuries. In Tachdjian s pediatric orthopaedics (3rd ed.). Philadelphia: WB Saunders Company: pp Hines, R. F., Herndon, W., & Evans, P. J. (1987). Operative treatment of medial epicondyle fractures in children. Clinical Orthopaedic & Related Research, 223, Horn, D. B., Herman, M. J., Crisci, D., Pizzutillo, P., & MacEwen, D. G. (2002). Fractures of the lateral humeral condyle: Role of the cartilage hinge in fracture stability. Journal of Pediatric Orthopaedics, 22(1), Kasser, J. R., & Beaty, J. H. (2006). Supracondylar fractures of the distal humerus. In Beaty JH, Kasser JR, Wilkins KE, & Rockwood CE (Eds.), Rockwood and Wilkins fractures in children (6th ed., pp ). Philadelphia: Lippincott Williams & Wilkins. Kocher, M., Kasser, J., & Waters, P. (2007). Lateral entry compared with medial and lateral entry pin fixation for completely displaced supracondylar humeral fractures in children. A randomized clinical trial. Journal of Bone and Joint Surgery, 89, Launay, F., Leet, A., Jacopin, S., Luc-Jouvre, J., Bollini, G., & Sponseller, P. (2004). Lateral humeral condyle fractures in children. A comparison of two approaches to treatment. Journal of Pediatric Orthopaedics, 24(4), Lyons, S. T., Quinn, M., & Stanitski, C. L. (2000). Neurovascular injuries in type III humeral supracondylar fractures in children. Clinical Orthopaedics and Related Research, 376, Orthopaedic Nursing January/February 2011 Volume 30 Number 1

7 Milbrandt, T. A., & Copley, L. A. (2004). Common elbow injuries in children: Evaluation, treatment and clinical outcomes. Current Opinion in Orthopaedics, 15, Milch, H. (1964). Fractures and fracture-dislocations of the humeral condyles. Journal of Trauma, 4, Mirsky, E. C., Karas, E. H., & Weiner, L. S. (1997). Lateral condyle fractures in children: Evaluation of classification and treatment. Journal of Orthopaedic Trauma, 11(2), Omid, R., Choi, P., & Skaggs, D. (2008). Supracondylar humerus fractures in children. Journal of Bone and Joint Surgery, 19(5), Rutherford, A. (1985). Fractures of the lateral humeral condyle in children. Journal of Bone and Joint Surgery American, 67(6), Simanovsky, N., Lamdon, R., Mosheiff, R., & Simanovsky, N. (2007). Underreduced supracondylar fracture of the humerus in children. Journal of Pediatric Orthopaedics, 27, Skaggs, D. L., & Mirzayan, R. (1999). The posterior fat pad sign in association with occult fracture of the elbow in children. Journal of Bone and Joint Surgery, 81, Skaggs, D. L., Cluck, M. W., Mostofi, A., Flynn, J. M., & Kay, R. M. (2001). Lateral-entry pin fixation in the management of supracondylar fractures in children. Journal of Bone Joint Surgery American, 86, Waters, P. M. (2006). Injuries of the shoulder, elbow, and forearm. Orthopaedic Knowledge Update Pediatrics, 3, For 37 additional continuing nursing education articles on pediatric topics, go to nursingcenter.com/ce. Orthopaedic Nursing January/February 2011 Volume 30 Number 1 17