How do you immobilize a coronoid process fracture?

Immobilization of Coronoid Process Fractures

For coronoid process fractures, rigid immobilization with a posterior splint or cast for 2 weeks is recommended, followed by progressive mobilization based on fracture stability and associated injuries. 1, 2

Classification and Initial Management

• Coronoid process fractures are classified according to the Regan and Morrey system, which guides treatment decisions based on fragment size and displacement 2, 3:

  • Type I: Avulsion of the tip
  • Type II: Fragment <50% of coronoid process
  • Type III: Fragment >50% of coronoid process

• CT imaging is recommended when radiographs are normal or indeterminate but clinical suspicion remains high, as it can identify occult fractures and clarify fracture morphology 1, 4

Immobilization Protocol by Fracture Type

Type I (Tip Avulsion) Fractures

• Immobilize in a posterior splint with the elbow at 90° flexion for 10-15 days 3
• Early mobilization after this period has shown excellent to good results in most cases 3

Type II (<50% Fragment) Fractures

• For stable, non-displaced fractures: Immobilization in a posterior splint for 2-3 weeks 2, 3
• For displaced fragments: Consider surgical fixation followed by early mobilization, which yields better outcomes than prolonged immobilization 3

Type III (>50% Fragment) Fractures

• Surgical fixation is generally recommended due to the critical role in elbow stability 2, 5
• Post-surgical immobilization should be limited to 2 weeks when possible to prevent stiffness 2

Special Considerations

• Immobilization beyond 21 days is associated with poorer outcomes and should be avoided when possible 2
• For fractures with associated elbow dislocation (76% of cases), careful assessment of stability after reduction is essential 2
• There is insufficient evidence to recommend for or against immobilizing the elbow to prevent forearm rotation 1

Rehabilitation Protocol

• After the initial immobilization period:
  • Begin active-assisted range of motion exercises to prevent stiffness 2
  • Gradually progress to active range of motion as pain allows 2
  • Avoid resistive exercises until radiographic evidence of healing (typically 6-8 weeks) 2

Surgical vs. Conservative Management

• Consider surgical fixation for:

  • Unstable fractures with associated elbow instability 2, 5
  • Type II and III fractures with significant displacement 3, 5
  • Fractures associated with elbow dislocations that remain unstable after reduction 2

• Stable osteosynthesis of the coronoid process is a positive prognostic factor for good functional outcomes 2

Follow-up Protocol

• Radiographic follow-up at approximately 3 weeks and at cessation of immobilization 1
• Monitor for signs of instability or loss of reduction, which may necessitate surgical intervention 2