Practice Essentials
Pediatric supracondylar humerus fractures (SCHFs) are common and significant injuries. They are distinctly different from adult SCHFs and thus are approached differently. Complications include neurovascular injury, compartment syndrome, malunion, and Volkmann contracture.
Timely diagnosis and proper management can prevent postinjury complications. These injuries are diagnosed by means of anteroposterior (AP) and true lateral radiographs. Lateral condyle fractures are a differential for supracondylar humerus fractures that must be considered when assessing patients and evaluating radiographs.
Type 1 and type 2A fractures may safely be treated nonoperatively if patients and parents are compliant. Type 2B, type 3, and flexion-type fractures require closed or open reduction and pin fixation. Pulseless and ischemic limbs require emergency reduction and fixation with or without vascular exploration by a vascular surgeon. The duration of immobilization varies, depending on injury severity, patient age, and local hospital protocols.
Background
SCHFs are the most common elbow fractures in children, accounting for approximately 12-17% of all pediatric fractures. [1, 2] The vast majority of SCHFs are seen in children younger than 10 years, with a peak incidence between 5 and 7 years. [2] The most common mechanism of injury is falling onto an outstretched hand with a hyperextended elbow. [3, 2] Rarely (< 5% of cases), SCHFs are seen with falls onto a flexed elbow, in which case they are referred to as flexion-type SCHFs. [4]
SCHFs have been associated with morbidity due to malunion, neurovascular complications, and compartment syndrome. Nonunion of an SCHF is rarely an issue, but if it does develop, it can result in long-term deformity and functional deficits.
Historically, the majority of SCHFs were treated by means of closed reduction and long arm casting with the elbow hyperflexed to greater than 100º. Although the hyperflexed position helped in maintaining reduction, it also led to problems associated with vascular compromise and subsequent Volkmann contracture.
Currently, management and follow-up of these fractures are determined on the basis of the Gartland classification (see Classification). [5] Type 1 and type 2A fractures may safely be treated nonoperatively, provided that patients and parents are compliant with therapy. Type 2B, type 3, and flexion-type fractures require closed or open reduction and pin fixation. There is no clear international evidence on the proportion of pediatric SCHFs that are treated operatively as opposed to nonoperatively.
SCHFs may also be seen in the elderly population, where they commonly result from low-energy trauma (eg, falling from a flat surface and landing directly on the elbow). These fractures represent completely different injury entities and should be worked up, assessed, and managed as such. In the geriatric setting, fracture comminution and nonunion are major concerns, and the choices of fixation method and therapeutic approach are drastically different from those seen in the pediatric setting. [6] For more detail on adult SCHFs, see Supracondylar Humerus Fractures.
Anatomy
The elbow is a synovial hinge joint between the distal humerus and the proximal radius and ulna. Radiographic evaluation of the pediatric elbow requires knowledge and understanding of the secondary ossification centers in the elbow so that normal anatomy can be distinguished from pathologic anatomy. The sequence of ossification follows a predictable pattern, as expressed in the acronym CRITOE (see Table 1 below). [7]
Table 1. Order of Ossification and Fusion of Elbow Ossification Centers (Open Table in a new window)
Ossification Center |
Age at Ossification Appearance (y) |
Age at Fusion (y) |
---|---|---|
Capitellum |
1 |
12 |
Radius |
3 |
15 |
Internal (medial) epicondyle |
5 |
17 |
Trochlea |
7 |
12 |
Olecranon |
9 |
15 |
External (lateral) epicondyle |
11 |
12 |
It should be noted that the ages of ossification and fusion can vary between individuals and are generally earlier in females than in males. [8] The capitellum is the first ossification center to be noted, appearing around the age of 1 year in both males and females. It should also be noted that the elbow is primarily cartilaginous in patients younger than 2.5 years and that structural injuries may be difficult to assess on plain radiography alone. [9]
Soft-tissue structures (both nerves and arteries) can be injured at the time of injury and intraoperatively. The most commonly involved neurovascular structures for SCHFs are the brachial artery and the median nerve. The brachial artery runs anterior to the distal humerus, superficial to the brachialis muscle. The median nerve crosses the elbow with the brachial artery. The anterior interosseous nerve (AIN), a branch of the median nerve, is the most commonly affected nerve in extension-type SCHFs. Neurapraxia of the ulnar nerve is commonly associated with flexion-type SCHFs.
Etiology
Pediatric SCHFs most commonly occur in children aged between 5 and 7 years, and their prevalence is similar in males and females. [2] They are usually a result of falling from a height. In children older than 4 years, falls are commonly from play equipment, such as monkey bars, trampolines, and climbing frames, whereas younger children often fall from household furniture, such as beds and lounges. [1, 3]
Prognosis
If pediatric SCHFs are promptly diagnosed and treated, no long-term complications or functional deficits are expected.
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(A, B) Anteroposterior (AP) and lateral elbow radiographs of 6-year-old girl with type 2A supracondylar humerus fracture with no rotational deformity on AP view. Anterior humeral line is crossing anterior to capitellum. (C, D) AP and lateral elbow radiographs of same patient after treatment with collar-and-cuff in elbow hyperflexion. Fracture is now reduced, and anterior humeral line now transects capitellum.
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(A, B) Elbow radiographs of 5-year-old boy with type 2B supracondylar humerus fracture (SCHF). Type 2B fracture differs from type 2A in that it has additional rotational component. (C, D) Postoperative radiographs of same patient showing cross Kirschner wire (K-wire) configuration in stabilization of SCHF. Intramedullary medial wire placement was done deliberately so as to provide valgus force and counteract any risk of fracture drifting into varus, leading to potential gunstock deformity. Lateral wire was placed to engage medial cortex as shown, for same reason.
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(A, B) Elbow radiographs of 5-year-old boy with type 2B supracondylar humerus fracture. (C, D) Postoperative radiographs of same patient showing two lateral Kirschner wire (K-wire) configurations. Diverging K-wire configurations are as recommended by Skaggs in 2008.
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(A, B) Elbow radiographs of 10-year-old girl showing type 3 supracondylar humerus fracture. (C, D) Intraoperative radiographs of same patient demonstrating reduction and fixation of fracture. Two Kirschner wires (K-wires) were used to stabilize lateral column, and one K-wire was used to stabilize medial column.
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(A, B) Elbow radiographs of 7-year-old girl with type 3 supracondylar humerus fracture. (C, D) Intraoperative radiographs of same patient demonstrating reduction and fixation of fracture. Three Kirschner wires (K-wires) were used to stabilize lateral column, and one K-wire was used to stabilize medial column. K-wires were sequentially added to achieve stability of each column in both internal and external rotation screenings.
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(A, B) Anteroposterior (AP) and lateral radiographs of 4-year-old boy showing lateral condyle fracture. This common fracture can be difficult to discern on AP radiographs and thus may be missed. Lateral condyle fracture is intra-articular and often requires more aggressive treatment, more intensive monitoring, or longer immobilization as compared with supracondylar humerus fracture.