Distal Humerus

Modern Study Review (AI-Generated)

High-Yield Summary

Distal humeral physeal injuries are uncommon pediatric fractures that require careful differentiation from lateral condyle fractures, elbow dislocations, and radial head dislocations. Early and accurate diagnosis is critical to avoid mismanagement, especially in infants and toddlers before ossification of the capitellum. Modern imaging techniques, including MRI and arthrography, assist in diagnosis when ossification centers are not visible. Treatment focuses on gentle reduction and immobilization, with vigilance for complications such as cubitus varus deformity.

Key Diagnostic Findings

Anatomy

• The distal humerus in children has a cartilaginous physis that is vulnerable to injury.
• Ossification of the capitellum occurs between 6-9 months of age, critical for radiographic interpretation.
• The relationship between the radius, ulna, and distal humerus is key to diagnosis.

Clinical Presentation

• Typically presents with elbow pain, swelling, and limited motion in infants and young children.
• History may be unclear; always consider non-accidental trauma (child abuse) in suspicious cases.

Imaging

• X-rays: Initial imaging modality; compare with contralateral elbow for subtle displacement.
• Arthrogram or MRI: Indicated if the capitellum is not ossified and diagnosis is uncertain.
• Key radiographic signs:
• Medial displacement of the capitellum relative to the distal humerus in physeal injuries.
• Posterior displacement of the capitellum in supracondylar fractures.
• Disruption of the radial head-capitellum alignment suggests dislocation or lateral condyle fracture.

Classification Systems

Current Gold Standard Treatment

Non-operative

• Indicated for minimally displaced injuries without neurovascular compromise.
• Gentle closed reduction under sedation: traction, correction of medial displacement and malrotation, flexion to 90°, and pronation.
• Immobilization in a splint or cast for 3-4 weeks.
• Close follow-up with serial imaging to monitor alignment and healing.

Operative

• Reserved for irreducible fractures, open fractures, or those with neurovascular injury.
• Techniques include percutaneous pinning or open reduction and internal fixation (ORIF) depending on fracture pattern and stability.
• Early intervention reduces risk of malunion and deformity.

Modern Complications & Outcomes

Complications

Outcomes

• With timely and appropriate management, most children regain full function without long-term disability.
• Residual deformity or stiffness is uncommon if complications are avoided.
• Early recognition of child abuse is critical to prevent recurrent injury and ensure patient safety.

Classic Clinical Notes

Distal Humerus

Distal Humeral Physeal Injuries

• Remember to think about child abuse when you see this injury!

DeLee Classification:

• A – prior to ossification of the capitellum (0-7 months)
• B – capitellum ossified (7 months to 3 years)
• C – capitellum well ossified and you can see a Thurston Holland fragment

Diagnostic Pearls:

• The confusion is distinguishing this injury from lateral condyle fracture, elbow dislocation, or radial head dislocation.
• For starters – get an X-ray of the normal limb.

1. If the capitellum has not ossified yet – consider getting an arthrogram or MRI if still wondering.
• Look at the relationship between the radius/ulna and humerus:
• If the radius/ulna are out laterally, it is more likely to be an elbow dislocation.
• If it is out medially, it is more likely to be a distal humeral physeal injury.
• Note: elbow dislocation in this age group is exceedingly RARE.

2. If the capitellum has ossified – look at the relationship between the radial head and the capitellum, and look at the relationship between the capitellum and the distal humerus.
• If the relationship is intact – think distal humeral physeal injury or supracondylar fracture; look at where the capitellum is in relation to the distal humerus.
• In a distal humeral physeal injury the capitellum is displaced medially, and you can confirm this by comparing it to the normal elbow X-ray.
• It is off posteriorly in the supracondylars.

• If the relationship between the capitellum and proximal radius is NOT intact – think elbow dislocation, lateral process fracture, or radial head dislocation.

Treatment

• Rule out child abuse.
• Decide if it needs to be reduced – gentle traction and correct the medial displacement and malrotation, then flex to 90 and pronate – put into a splint.
• Watch out for cubitus varus – it can develop with this injury.

Last Updated on January 25, 2026 by orthonet