In a series of 150 children with supracondylar fractures of the humerus, which of the following is the most common type of fracture displacement according to Gartland classification?

Explanation

## Gartland Classification and Most Common Type **Key Point:** Type III supracondylar fractures (complete displacement with loss of all cortical contact) are the most common presentation, accounting for approximately 50–60% of all supracondylar fractures. ### Gartland Classification Overview | Type | Displacement | Posterior Cortex | Frequency | Clinical Significance | |---|---|---|---|---| | **Type I** | Minimal or none | Intact | 5–10% | Stable, rarely needs reduction | | **Type II** | Posterior angulation | Intact (hinge) | 30–40% | Partially stable, may need reduction | | **Type III** | Complete displacement | Lost | 50–60% | Unstable, requires reduction ± fixation | | **Type IV** | Displacement in all planes | Lost | <5% | Rare, highly unstable, complex reduction | ### Why Type III Is Most Common 1. **Mechanism:** The typical FOOSH injury with elbow extension generates sufficient force to completely displace the distal fragment 2. **Biomechanics:** Once the posterior cortex fails, the fracture becomes unstable and prone to complete displacement 3. **Age factor:** Children's bones are more prone to complete fracture-displacement than greenstick patterns ### Clinical Implications of Type III **High-Yield:** Type III fractures require: - Urgent reduction (closed or open) - Assessment for neurovascular injury (especially brachial artery and median nerve) - Percutaneous pinning or open reduction with internal fixation (ORIF) to maintain reduction - Careful post-reduction imaging to confirm anatomic alignment **Warning:** Type III fractures have the highest risk of: - Neurovascular complications (15–20% incidence) - Loss of reduction if managed conservatively - Cubitus varus (gunstock deformity) if inadequately reduced **Clinical Pearl:** A completely displaced (Type III) supracondylar fracture with a pulseless hand requires urgent reduction—do not delay for imaging. Reduction often restores distal perfusion by relieving stretch on the brachial artery. ### Mnemonic for Gartland Types **"I See Three Fractures"** — Type I (Intact), Type II (hinge), Type III (Total displacement), Type IV (Four-way displacement, rare). [cite:Rockwood & Green's Fractures in Children 9e Ch 13]