Radial Head

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 timely management are essential to restore pain-free motion and prevent chronic instability or stiffness. The Mason classification remains the cornerstone for guiding treatment, with modern adaptations emphasizing associated ligamentous injuries and fracture displacement thresholds.

Key Diagnostic Findings

Anatomy

• The radial head articulates with the capitellum and the radial notch of the ulna, enabling forearm pronation and supination.
• It is a secondary stabilizer of the elbow, particularly against valgus stress, in conjunction with the medial collateral ligament (MCL).

Clinical Presentation

• Lateral elbow pain, swelling, and tenderness over the radial head.
• Limited forearm rotation and elbow flexion-extension.
• Possible mechanical symptoms if fracture fragments are displaced.

Imaging

• Standard elbow radiographs: AP, lateral, and oblique views.
• CT scan for complex or comminuted fractures to assess displacement and articular involvement.
• MRI if ligamentous injury is suspected.

Classification Systems

Note: The original Mason classification has been expanded to include ligamentous injuries (Type IV), reflecting the importance of soft tissue assessment.

Current Gold Standard Treatment

Non-operative

• Indicated for Mason Type I and select Type II fractures with minimal displacement and stable elbow.
• Early mobilization to prevent stiffness.
• Pain control and functional bracing as needed.

Operative

• Indicated for displaced Type II fractures (>2 mm displacement, >30% articular involvement), Type III comminuted fractures, and all Type IV fractures with associated instability.
• Options include open reduction and internal fixation (ORIF), radial head excision (rarely), or radial head arthroplasty in unreconstructable fractures.
• Ligament repair or reconstruction if MCL or LCL injury is present.

Modern Complications & Outcomes

Complications

Outcomes

• Early diagnosis and appropriate treatment yield excellent functional outcomes with restoration of pain-free motion.
• Radial head arthroplasty improves outcomes in unreconstructable fractures with instability.
• Rehabilitation focusing on range of motion and strengthening is critical for optimal recovery.

Classic Clinical Notes

Radial Head

Mason Classification

• I – Non-displaced
• II – >2 mm displacement, >30% of radial head involved
• IV – Associated with MCL injury
• IV – Associated with LCL injury

Last Updated on January 25, 2026 by orthonet