Edited by Nattaly Greene, David Evans - 7/1/2021
Descriptors
- Described as proximal ulna fractures or plastic deformation of the ulna with disruption of proximal radioulnar joint and radiocapitellar dislocation
- Accounts for 0.4% of all forearm fractures in children and normally affect children between ages 4-10 years of age after a fall onto an outstretched hand
Exam Pearls
The child normally presents with pain and swelling at the elbow. There might be deformity at the elbow and limitations in range of motion, although not always obvious. Assess for neurological deficits in the posterior interosseous nerve (PIN) and ulnar nerve
One should palpate over radial head because it can reduce spontaneously. If there is a radial head dislocation, look for plastic deformation of ulna because isolated radial head dislocations almost never occur
Workup
Radiographs: AP and lateral films of the elbow, forearm, and wrist
Radiocapitellar alignment (a line down the radial shaft should pass through the center of the capitellar ossification center) should be evaluated on all views and the radial shaft should point to the center of the capitellum on any radiographic view
Plastic deformation of the ulna can be easily missed but associated with radiocapitellar dislocation. If unclear; obtain AP and lateral xray of the contralateral elbow.
Other imaging: Dynamic imaging with fluoroscopy may be helpful
Bado classification: Based on the direction of radial head dislocation which follows apex of the ulnar fracture. Helps guide management and understanding of injury pattern.
Type I: Anterior radial head dislocation with apex anterior ulnar angulation. Usually results from fall onto an outstretched hand. Most common pattern
Type II: Posterior radial head dislocation with apex posterior angulation of the ulna. These are the result of an axial load onto partially flexed elbow or direct trauma to a proximal supinated forearm
Type III: Lateral radial head dislocation and varus angulated (apex lateral) proximal ulna fracture. Usually occurs as the result a fall onto an outstretched hand with the forearm in pronation and an associated varus stress
Type IV: Characterized by an anterior radial head dislocation in the setting of proximal ⅓ transverse fractures of the radius and ulna. Fall onto an outstretched hand with the forearm in pronation
Management
Need for acute intervention: Yes, immobilization with reduction
Bado type I and III
Radial head is stable following reduction and length stable ulnar fracture pattern
Reduction technique uses traction - radial head will reduce spontaneously with reduction of the ulna and restoring ulnar length. Elbow flexion is the main reduction maneuver
If the radial head is irreducible or unstable after fixation of ulna, then it is necessary to perform an open reduction and internal fixation
Weight-bearing and range of motion: Nonweightbearing of the affected extremity
Type of immobilization: Type I - 110 of flexion in full supination (tighten interosseous membrane and relax biceps tendon) Tyle II - Full extension Type III - Full extension and valgus mold
Admission or discharge status: Typically discharged following reduction and casting
Anticoagulation: None
Antibiotics: None
Surgical Indications
Absolute: Open fractures and irreducible radial head following reduction of ulna