A 68-year-old woman from Delhi falls on her outstretched right hand while descending stairs. She presents to the emergency department with severe wrist pain, swelling, and a characteristic 'dinner fork' deformity. X-ray of the right wrist shows a transverse fracture of the distal radius with dorsal displacement and angulation of the distal fragment. The distal ulna is intact. What is the most likely diagnosis?

## Diagnosis: Colles Fracture **Key Point:** Colles fracture is a transverse fracture of the distal radius with **dorsal displacement and dorsal angulation** of the distal fragment, classically described as a 'dinner fork' deformity on lateral X-ray. ### Clinical Features - **Mechanism:** Fall on outstretched hand (FOOSH) with wrist in extension - **Demographics:** Most common in elderly women with osteoporosis - **Deformity:** Dinner fork appearance (dorsal prominence of wrist) - **Associated injury:** Ulnar styloid fracture (~50% of cases); distal ulna is intact in uncomplicated Colles ### Radiological Findings | Feature | Colles | Smith | |---------|--------|-------| | **Fracture line** | Transverse, distal radius | Transverse, distal radius | | **Displacement** | **Dorsal** | **Volar** | | **Angulation** | **Dorsal** | **Volar** | | **Deformity** | Dinner fork | Reverse dinner fork | | **Mechanism** | FOOSH (extension) | Fall on flexed wrist or direct blow | | **Ulna** | Often styloid fracture | Intact or ulnar shaft fracture | **High-Yield:** The 'dinner fork' deformity is pathognomonic for Colles fracture—dorsal displacement creates the characteristic silhouette on lateral view. ### Complications 1. **Acute:** Carpal tunnel syndrome, compartment syndrome 2. **Late:** Malunion, post-traumatic arthritis, rupture of extensor pollicis longus (EPL) 3. **Functional:** Loss of grip strength, reduced wrist mobility **Clinical Pearl:** Colles fracture in a young patient or from high-energy trauma should raise suspicion for associated injuries (scaphoid fracture, ligamentous injury) and warrant careful imaging and assessment. [cite:Rockwood and Green's Fractures in Adults Ch 17]