Makindo Medical Notes

🩺 Always document anatomical snuffbox tenderness and request dedicated scaphoid views if tenderness is present. In children under 14, obtain AP/Lateral wrist views only to reduce radiation. ⚠️ Scaphoid fractures have a high complication rate if missed — with a 5–40% risk of avascular necrosis (AVN) or non-union.

📍 Introduction

• The scaphoid is one of the carpal bones in the proximal row on the radial (thumb) side of the wrist.
• It is palpated in the anatomical snuffbox, bordered by the tendons of extensor pollicis longus and abductor pollicis longus/extensor pollicis brevis.
• Prone to avascular necrosis because blood supply enters distally and travels proximally.

⚡ Causes

• Common in young, active individuals (sports injuries, falls, road traffic accidents).
• If untreated, may lead to non-union and early wrist arthritis.

🩸 Mechanism of Injury

• Classic mechanism: Fall On Outstretched Hand (FOOSH) with wrist hyperextension and radial deviation.
• Fracture sites: waist (65%), proximal pole (25%), distal pole (10–15%).
• Other causes: skiing, snowboarding, direct trauma in RTCs.

🔎 Clinical Presentation

• Wrist swelling is common; bruising/deformity is rare.
• Anatomical snuffbox tenderness (dorsal wrist at base of thumb).
• Scaphoid tubercle tenderness (volar/palmar wrist).
• Scaphoid compression test: pain when axial load applied through thumb metacarpal.
• Pain with resisted pronation may also be present.

🖼️ Investigations

• X-rays (scaphoid views): often miss up to 30% of fractures initially.
• MRI: gold standard for detecting occult fractures (sensitivity >95%).
• CT scan: useful for fracture classification, displacement, and surgical planning.

⚠️ Complications

• Delayed union: slow healing due to poor blood supply.
• Non-union: failure to heal → chronic pain, reduced grip strength.
• Avascular necrosis (AVN): especially in proximal pole fractures.
• Osteoarthritis: long-term complication of non-union or AVN.

🛠️ Management

• If X-ray is normal but suspicion is high: immobilise in a thumb spica cast and repeat imaging in 10–14 days (X-ray or MRI depending on local protocol).
• Non-operative: Cast immobilisation (usually 6–12 weeks), especially for non-displaced distal and waist fractures.
• Operative: Indicated for displaced, proximal pole fractures, or non-union. Options: percutaneous screw fixation or ORIF (open reduction internal fixation).
• All cases should be referred to a fracture clinic for follow-up.

📚 References

• Orthobullets – Scaphoid fracture
• HSS – Scaphoid fractures
• BOAST Guideline – Scaphoid fractures