Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

Radial Head and Neck Fractures in Children

Overview

• Uncommon pediatric elbow injury.
• Peak incidence around 9 years of age.
• Usually caused by a valgus force following a fall on an outstretched hand.

Types of Fractures

• Non displaced fractures.
• Displaced fractures.
• Angulated (tilted) fractures.
• Translocated fractures.

Location

• Physeal fractures (Salter Harris injuries).
• Metaphyseal fractures (radial neck fractures).

Ossification Centers Around the Elbow (CRITOE)

Mnemonic: CRITOE (1, 3, 5, 7, 9, 11 years)

• Capitellum – 1 year.
• Radial head – 3 years.
• Internal (medial) epicondyle – 5 years.
• Trochlea – 7 years.
• Olecranon – 9 years.
• External (lateral) epicondyle – 11 years.

Imaging

Standard views

• Anteroposterior and lateral radiographs of the elbow.
• Include the forearm in the radiographs.

Radiological rule

• The radial head must align with the capitellum on every radiographic view.

Radiocapitellar view

• Elbow flexed to 90 degrees.
• Thumb pointing upward.
• X ray beam angled 45 degrees proximally.

Fat pad sign

• Posterior fat pad is always abnormal and indicates an occult fracture.
• May be absent in extra articular radial neck fractures.

Acceptable Angulation

• Angulation of 30 degrees or less is generally acceptable.

Treatment

Non displaced fractures or angulation 30 degrees or less

• Immobilization alone.

Fractures with angulation greater than 30 degrees

• Closed reduction.

Closed reduction technique

• Longitudinal traction.
• Forearm supination.
• Elbow extension.
• Varus stress.
• Direct pressure on the radial head medially and the shaft laterally.

If closed reduction fails

• Percutaneous reduction using a K wire joystick technique.

Open reduction

• Reserved as the final option.
• Consider only when residual angulation exceeds 45 degrees after closed and percutaneous reduction.
• Avoid whenever possible because of the higher complication rate.

Fixation

• K wire fixation may be used following reduction when required.

Complications

• Radioulnar synostosis, particularly after excessive dissection or open reduction.
• Loss of forearm rotation, especially pronation and supination.
• Osteonecrosis of the radial head due to vascular injury.
• Nonunion, usually caused by periosteal interposition.

Important Clinical Points

• Complication rates increase after open reduction.
• Outcomes are generally poorer in children older than 10 years.

Clinical Pearls

• Always confirm radiocapitellar alignment.
• A posterior fat pad sign should be considered evidence of an occult fracture until proven otherwise.
• Follow the treatment sequence of closed reduction, then percutaneous reduction, and finally open reduction if necessary.
• Perform repeated neurovascular examinations.
• Monitor for compartment syndrome, particularly if increasing analgesic requirements are noted.

Exam Pearls

• CRITOE ossification sequence: 1, 3, 5, 7, 9, 11 years.
• Angulation of 30 degrees or less is treated with immobilization.
• Angulation greater than 30 degrees requires reduction.
• Residual angulation greater than 45 degrees after reduction may require open reduction.
• The radial head should always align with the capitellum on every radiographic view.
• Posterior fat pad sign indicates an occult fracture.
• Open reduction should be the last treatment option because of its higher complication rate.