## Herbert Classification of Scaphoid Fractures **Key Point:** The Herbert classification divides scaphoid fractures into **acute (A, B)** and **chronic (C, D)** types. Type B4 (proximal pole fracture) has the worst prognosis due to precarious blood supply. ### Herbert Classification Overview | Type | Subtype | Location | Stability | Prognosis | | --- | --- | --- | --- | --- | | **A** | A1 | Tubercle | Stable | Excellent | | **A** | A2 | Distal pole | Stable | Excellent | | **B** | B1 | Distal third | Unstable | Good | | **B** | B2 | Middle third (waist) | Unstable | Fair | | **B** | B3 | Proximal third | Unstable | Poor | | **B** | B4 | Proximal pole | Unstable | **Very Poor** | | **C** | — | Any location | — | Delayed union | | **D** | — | Any location | — | Non-union | ### Why B4 is Highest Risk **High-Yield:** Type B4 (proximal pole fracture) has: 1. **Retrograde blood supply** — the proximal pole is the last to receive perfusion 2. **Smallest fracture surface area** — less cancellous bone for healing 3. **Highest AVN rate** — 10–12% without intervention 4. **Highest non-union rate** — up to 50% if untreated **Clinical Pearl:** Proximal pole fractures often require **percutaneous screw fixation** or **open reduction** because immobilization alone fails in >50% of cases. ### Mnemonic **"Proximal = Problem"** — Proximal pole fractures (B4) are the most problematic and require operative intervention. 
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