Rheumatology and Orthopedics· Topic 17.10 Metabolic bone disease and musculoskeletal trauma· 17.10.19

Scaphoid fracture

Scaphoid fracture follows a fall onto an outstretched hand and is suspected by anatomic snuffbox tenderness even with a normal initial radiograph; nondisplaced fractures are treated with thumb spica immobilization and displaced or unstable fractures with screw fixation.

11 min read4 practice questions7 key factsSubscriber article
  • Topic review
    The full article, organized the way the exam asks it.
  • ABIM-format MCQs
    Vignettes with an explanation for every wrong answer.
  • Key facts
    The numbers and thresholds worth memorizing, up front.
  • AI tutor
    MedBrain answers the question you're stuck on.

What this article covers

  • Overview

    Scaphoid fracture is a fracture of the scaphoid (navicular) carpal bone, the most commonly fractured carpal bone, occurring classically after a fall onto an outstretched hand in young male athletes.

  • Epidemiology

    The scaphoid is the most commonly fractured carpal bone, reflecting its position on the floor of the anatomic snuffbox where it bears direct load during a fall onto an outstretched hand.

  • Risk factors

    Fall onto an outstretched hand, by far the dominant mechanism and the historical feature that should raise suspicion in any wrist injury.

  • Pathophysiology

    Axial load transmitted through a hyperextended, radially deviated wrist during a fall onto an outstretched hand concentrates force on the scaphoid, which bridges the proximal and distal carpal rows…

  • Clinical features

    Tenderness and swelling in the anatomic snuffbox, the hallmark finding, bounded by the extensor pollicis longus tendon medially and the abductor pollicis longus and extensor pollicis brevis tendons laterally.

  • Differential diagnosis

    Distal radius fracture: tenderness and swelling centered over the distal radius rather than the anatomic snuffbox, also from a fall onto an outstretched hand, usually visible on initial radiograph.

  • Diagnosis

    Scaphoid fracture is confirmed radiographically (plain film, or CT/MRI when radiographs are normal but suspicion is high), and the clinching clinical basis for suspecting it before imaging is a fall…

  • Management

    First, splint every patient with suspected scaphoid fracture (positive exam, regardless of initial radiograph result) in a thumb spica splint while definitive imaging or follow-up is arranged, since…

  • Complications

    Avascular necrosis of the proximal scaphoid fragment, a direct consequence of the retrograde blood supply being disrupted by the fracture; risk is highest with proximal pole fractures.

  • Prognosis

    Nondisplaced or minimally displaced fractures diagnosed and immobilized promptly generally heal well with cast or splint treatment alone.

  • Prevention

    Maintain a high index of suspicion and low threshold to splint any patient with a fall-onto-outstretched-hand mechanism and anatomic snuffbox or scaphoid tubercle tenderness, even with a normal…

Read the whole article

Subscribing to Internal Medicine opens every article, the full question bank and MedBrain, on the web, iPhone and Android.