What is the treatment for a coronoid process fracture at the elbow?

Treatment of Coronoid Process Fracture at the Elbow

The treatment of coronoid process fractures should be based on fracture size, displacement, and elbow stability, with surgical fixation recommended for fractures involving more than 50% of the coronoid process due to significant risk of elbow instability. 1

Classification and Initial Assessment

Coronoid process fractures are typically sequelae of elbow dislocations and are commonly associated with soft tissue injuries 2. Assessment should include:

• CT imaging without contrast when radiographs are equivocal but clinical suspicion remains high 2, 3
• Evaluation for associated injuries to tendons and ligaments 2
• Classification based on fracture size:
  • Type I: <25% of coronoid process
  • Type II: 25-50% of coronoid process
  • Type III: >50% of coronoid process 4, 1

Treatment Algorithm

Conservative Management

• Indicated for:
  • Type I and II fractures (<50% of coronoid process) 1
  • Stable elbow joint
  • Minimal displacement (<3mm interfragmentary gap)
  • Minimal angulation (<10 degrees) 3

Conservative treatment includes:

• Simple arm sling for immobilization 3
• Early mobilization to prevent stiffness 3
• Directed home exercise program with active motion exercises 3

Surgical Management

• Indicated for:
  • Type III fractures (>50% of coronoid process) 1
  • Unstable elbow joint
  • Displacement >3mm or angulation >10 degrees 3
  • Associated injuries (terrible triad, varus posteromedial rotational instability) 2, 5

Surgical options include:

1. Open reduction and internal fixation with plate and screws applied to the medial surface of the coronoid 5
2. Arthroscopic reduction and internal fixation for selected cases 6
3. Fragment-specific fixation for anteromedial facet fractures 5

Rehabilitation Protocol

• Early mobilization after stable surgical fixation 3
• NSAIDs for pain and inflammation control 3
• Regular assessment of wound healing and radiographic union 3
• Limiting the duration of immobilization to reduce complications 3

Complications and Pitfalls

• Failure to recognize and properly treat Type III fractures leads to posterior elbow instability, especially beyond 60 degrees of flexion 1
• Inadequate fixation of anteromedial facet fractures can result in varus subluxation, arthrosis, and poor functional outcomes 5
• Potential complications include joint stiffness, chronic pain, recurrent instability, and post-traumatic arthritis 3

Key Considerations

1. Biomechanical studies show that fractures involving >50% of the coronoid process significantly compromise elbow stability under axial loading 1
2. Anteromedial facet fractures represent a distinct pattern requiring specific attention to prevent varus instability 5
3. CT imaging is essential for accurate assessment of fracture morphology and planning appropriate treatment 2
4. Secure fixation of coronoid fractures in unstable patterns usually restores good elbow function 5

For optimal outcomes, the treatment approach must address both the coronoid fracture and any associated soft tissue or bony injuries to restore elbow stability and function.