Supracondylar fracture

This page is for pediatric patients; for adult patients see distal humerus fracture

Background

• Most common elbow fracture in patients age <8yr
• 95% are extension type (FOOSH mechanism)

Clinical Features

Do not encourage active/passive elbow movement until displaced fracture has been ruled-out

• Pain, swelling, very limited range of motion
• Non-displaced fracture may have limited swelling, but child will refuse to move arm
• TTP of posterior, distal humerus
• If evidence of S-shape configuration or skin dimpling, splint before xray

Differential Diagnosis

Humerus Fracture Types

Humeral anatomy

• Adult
  • Proximal
  • Shaft
  • Distal
    • Capitellum
    • Trochlea
    • Condylar
• Pediatric
  • Proximal
  • Shaft
  • Distal
    • Supracondylar
    • Lateral epicondyle
    • Medial epicondyle

Elbow Diagnoses

Radiograph-Positive

• Distal humerus fracture
• Radial head fracture
  • Essex-Lopresti fracture
• Capitellum fracture
• Olecranon fracture
• Elbow dislocation

Radiograph-Negative

• Biceps tendon rupture/dislocation
• Lateral epicondylitis
• Medial epicondylitis
• Olecranon bursitis (nonseptic)
• Pronator teres syndrome
• Septic bursitis

Pediatric

• Nursemaid's elbow
• Supracondylar fracture
• Lateral epicondyle fracture
• Medial epicondyle fracture
• Olecranon fracture
• Radial head fracture
• Salter-Harris fractures

Evaluation

Normal pediatric elbow alignment

Anterior "Sail sign"

• Lateral and AP radiographs are usually sufficient, and in many instances demonstrate an obvious fracture. Often, however, no fracture line can be identified. In such cases assessing for indirect signs is essential:
  • Anterior fat pad sign (sail sign): the anterior fat pad is elevated by a joint effusion and appears as a lucent triangle on the lateral projection
  • Posterior fat pad sign
  • Anterior humeral line should intersect the middle third of the capitellum in most children although, in children under 4, the anterior humeral line may pass through the anterior third without injury

Imaging

• True lateral elbow

• • Anterior humeral line should intersect with middle third of capitellum (see pediatric elbow alignment)
    • If not, consider supracondylar fracture (or lateral condyle fracture)
• Forearm/wrist views
  • Co-injuries are common with elbow fracture

Gartland Classification

• Type I
  • Nondisplaced with evidence of elbow effusion (ant sail sign and/or posterior fat pad)
• Type II
  • Displaced with intact posterior periosteum
  • Anterior humeral line is displaced anteriorly relative to capitellum
• Type III
  • Displaced with disruption of anterior and posterior periosteum
    • If distal fragment is posteromedially displaced: radial nerve injury
    • If distal fragment is posterolaterally displaced: median nerve, brachial artery injury
• Type IV
  • Complete periosteal disruption with instability in flexion and extension

Management

General Fracture Management

• Acute pain management
• Open fractures require immediate IV antibiotics and urgent surgical washout
• Neurovascular compromise from fracture requires emergent reduction and/or orthopedic intervention
• Consider risk for compartment syndrome

Specific Management

• Immobilize using double sugar tong or long-arm posterior splint
  • Elbow at 90 degrees, forearm in pronation or neutral rotation
• Types II & III should have orthopedic consult in the ED

Disposition

• Type I fractures may be discharged with ortho follow-up in 48 hours
• Type II and III fractures generally require admission

Complications

Vascular

• Volkmann Ischemic Contracture (Compartment Syndrome of forearm)
  • Occurs more commonly when forearm is also fractured
  • Mere lack of a radial pulse does not indicate ischemia unless accompanied by: refusal to open hand, pain with passive extension of fingers, or forearm tendernes
• Brachial artery injury - suggested by ecchymosis over anteromedial aspect of forearm
  • Strong collaterals might mask vascular injury

Neurologic

• Majority of nerve injuries are neuropraxias without long-term sequelae
• Median nerve injury (typically AIN)
  • Motor: Weakness of hand flexors (difficulty making "OK" sign), abduction of thumb
  • Sensory: Altered two-point sensation on palmar surface of thumb, IF, MF
• Radial nerve injury
  • Motor: Weakness of wrist extension, thumb extension (thumbs up)
  • Sensory: Altered sensation in dorsal thumb-index web space
• Ulnar nerve injury
  • Motor: Weakness of index finger abduction
  • Sensory: Altered two-point discrimination over tip of little finger

See Also

• Elbow diagnoses
• Elbow Fracture (Peds)
• Elbow Xray Peds

External Links

• Pediatric Emergency Playbook Podcast: Pediatric Elbow Injuries