In a scaphoid fracture, which of the following clinical signs is most sensitive for detecting the fracture on physical examination?

Explanation

## Clinical Diagnosis of Scaphoid Fracture **Key Point:** Tenderness in the anatomical snuffbox is the most sensitive clinical sign for scaphoid fracture, though it is not specific. ### Anatomical Snuffbox Tenderness **High-Yield:** The anatomical snuffbox is the triangular depression on the dorsal wrist formed by: - Medially: tendons of extensor carpi radialis longus and brevis - Laterally: tendon of extensor pollicis longus - Floor: scaphoid and trapezium bones ### Sensitivity vs. Specificity | Clinical Sign | Sensitivity | Specificity | Comment | | --- | --- | --- | --- | | Snuffbox tenderness | 90–95% | 40–50% | Most sensitive but many false positives | | Scaphoid compression test | 70–80% | 60–70% | Moderate sensitivity and specificity | | Swelling over dorsal wrist | 60–70% | 50% | Non-specific; seen in many wrist injuries | | Loss of extension strength | 20–30% | 80% | Insensitive; indicates advanced pathology | **Clinical Pearl:** A patient with snuffbox tenderness after a fall on an outstretched hand (FOOSH) must be treated as a scaphoid fracture until proven otherwise, even if initial X-rays are negative. Repeat imaging in 10–14 days or early CT/MRI is indicated. **Mnemonic:** **SNUFF** — **S**ensitive, **N**ot specific, **U**nderlying scaphoid, **F**all on outstretched hand, **F**racture must be ruled out. ### Why Other Signs Are Less Sensitive - Scaphoid compression test requires specific technique and patient cooperation - Swelling is non-specific and may indicate soft tissue injury - Loss of extension strength indicates severe injury or chronic AVN, not acute fracture