Radial Head Fractures

Modern Study Review (AI-Generated)

High-Yield Summary

Radial head fractures are common elbow injuries that significantly impact forearm rotation and elbow stability. Accurate classification and assessment of associated ligamentous or bony injuries are critical for guiding treatment. Modern management balances early mobilization to preserve function with surgical intervention when instability or mechanical block is present. Understanding the Mason classification and its updates is essential for optimal outcomes.

Key Diagnostic Findings

Anatomy

• The radial head articulates with the capitellum and proximal ulna, playing a crucial role in elbow stability and forearm rotation.
• It serves as a secondary stabilizer to valgus stress, especially when the medial collateral ligament (MCL) is compromised.

Clinical Presentation

• Lateral elbow pain, swelling, and tenderness over the radial head.
• Mechanical block to forearm rotation or elbow flexion may indicate displaced or comminuted fractures.
• Associated injuries (MCL tears, coronoid fractures, interosseous membrane injury) suggest instability.

Imaging

• X-rays: AP, lateral, and oblique views to assess displacement and comminution.
• CT scan: Recommended for complex fractures to evaluate fragment size and joint congruity.
• MRI: Useful for detecting associated soft tissue injuries (MCL, interosseous membrane).

Classification Systems

Current Gold Standard Treatment

Non-operative

• Indicated for Mason Type I and stable Type II fractures without mechanical block or instability.
• Early range of motion (ROM) exercises to prevent stiffness and maintain function.
• Close monitoring for signs of instability or delayed displacement.

Operative

• Indications:
• Displaced Type II fractures with mechanical block to motion.
• Unstable elbow due to associated ligamentous or bony injuries (MCL, coronoid, interosseous membrane).
• Comminuted Type III fractures with instability or failed non-operative management.
• Surgical options:
• Open Reduction and Internal Fixation (ORIF): For reconstructible fragments in Type II and select Type III fractures.
• Radial Head Arthroplasty: Preferred for unreconstructible comminuted fractures with instability.
• Radial Head Excision: Reserved for isolated comminuted fractures without instability or associated injuries; less favored due to risk of valgus instability and proximal migration of the radius.

Modern Complications & Outcomes

Complications

Outcomes

• Early motion protocols improve functional outcomes and reduce stiffness.
• ORIF yields good results in simple displaced fractures but may fail in comminuted patterns.
• Arthroplasty restores stability and motion in complex fractures but requires careful sizing and technique.
• Excision alone is rarely recommended today due to risk of chronic instability and altered kinematics.

Classic Clinical Notes

Radial Head Fractures

(Mason Classification)

• Type I – undisplaced
• Type II – Displaced single fragment
• Type III – Comminuted
• Type IV (Johnston) – associated with elbow dislocation

Treatment Guidelines:

• Type I: early range of motion (ROM)
• Type II: controversial
• Stable elbow with full ROM = conservative treatment
• Block to rotation, associated injury potentially compromising elbow stability (e.g., MCL, interosseous membrane, coronoid fracture, elbow dislocation) = consider ORIF
• Type III: excision vs. replacement
• Excision reserved for those with isolated comminution (i.e., no forearm or wrist pain, no associated instability or injuries contributing to elbow instability such as MCL or coronoid)

Last Updated on January 25, 2026 by orthonet