A 7-year-old boy presents to the emergency department following a fall on an outstretched hand (FOOSH). X-rays reveal a supracondylar fracture of the humerus. Regarding the clinical features and management of supracondylar fractures, all of the following are true EXCEPT:

Explanation

## Deformity Pattern in Supracondylar Fractures **Key Point:** In supracondylar fractures of the humerus, the distal fragment is displaced **posteriorly** (not anteriorly). This is because the mechanism is a fall on an outstretched hand (FOOSH) with the elbow in extension — the olecranon acts as a fulcrum, driving the distal fragment posteriorly. This is called an **extension-type** fracture and accounts for ~98% of all supracondylar fractures. The distal fragment shows: - **Posterior displacement** (most common) - **Posterior angulation** (apex anterior) - Medial or lateral rotation > **High-Yield:** "Anterior angulation of the distal fragment" is **incorrect** — it is *posterior* angulation/displacement that is the hallmark deformity. This is a classic exam trap. ## Why the Other Options Are TRUE (and therefore not the answer) ### Option B — Brachial Artery vs. Radial Nerve Injury **Clinical Pearl:** The brachial artery runs anterior to the distal humerus and is vulnerable to injury from displaced fracture fragments. Brachial artery injury occurs in **5–20%** of cases, while radial nerve injury occurs in only **2–6%**. Hence, brachial artery injury is indeed more common. *(Rockwood & Wilkins' Fractures in Children)* ### Option C — Volkmann's Ischemic Contracture **Warning:** Failure to promptly recognize and treat vascular compromise leads to forearm muscle ischemia → fibrosis → **Volkmann's ischemic contracture**, a devastating late complication. This is preventable with timely surgical intervention. *(Campbell's Operative Orthopaedics)* ### Option D — Fracture Location Supracondylar fractures occur in the **metaphyseal region above the condyles**, between the olecranon and coronoid fossae — a thin, weak zone of the distal humerus. While the olecranon fossa is a nearby landmark, the fracture line passes *through* or *above* this region, not exclusively at the olecranon fossa level. This statement is broadly accepted as true in standard references. ## Summary Table | Feature | Correct Fact | |---|---| | Deformity | **Posterior** displacement/angulation of distal fragment | | Most common type | Extension-type (~98%) | | Vascular injury | Brachial artery (5–20%) > Radial nerve (2–6%) | | Late complication | Volkmann's ischemic contracture | **Reference:** Maheshwari's Essential Orthopaedics, 5th ed.; Rockwood & Wilkins' Fractures in Children, 8th ed.