Radial head subluxation

Background

• Radial head subluxation due to longitudinal traction on arm
  • Annular ligament of radius displaces into radiocapitellar articulation

Clinical Features

• Sudden onset
• Age 1y-5y (peak 2y-3y)
• Typical history: Sudden pull on extended arm. Swinging the child by adult while playing.
• Absence of edema, focal tenderness, or bruising

Differential Diagnosis

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

• If classic history/physical
  • → proceed directly to reduction maneuver without imaging
• If unclear or atypical history/physical
  • → consider x-ray first and/or alternative diagnosis
  • typically will not present with warmth, swelling, tenderness to direct palpation, or bruising

Management

Reduction

Hyperpronation has greater first try success rate (94% vs 69%), but both have similar overall reduction rate; consider doing both techniques at once in quick succession

• Hyperpronation Technique
  • Hold patient's elbow at 90 degrees with one hand
  • With other hand hyperpronate patient's wrist
• Supination Technique
  • Hold patient's elbow at 90 degrees with one hand
  • With other hand supinate patient's wrist and flex elbow

Post-Reduction

• If successful patient will have FROM within 30min
• If unsuccessful after multiple attempts, obtain x-ray and consider alternative diagnoses (e.g. Salter-Harris fracture)

Disposition

• If reduced and moving arm, outpatient
  • Sling and/or other immobilization are contra-indicated

See Also

• Elbow diagnoses