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Case of the Week 384

What sign is depicted on this image?

  • 51 year-old with wrist pain

Frontal radiograph of the wrist

1. Pronator quadratus sign
2. Triangular lunate sign
3. Ring sign
4. Carpal fusion sign
5. Target sign

Additional Images - None


Additional Images






3. Ring Sign



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Scaphoid Cortical Ring Sign

General Considerations

  • The scaphoid cortical ring sign is produced by the foreshortened appearance of the distal pole of the scaphoid rotated on its axis by scapholunate dissociation, one of the manifestations of carpal instability syndromes
  • It may, however, be present normally and should be evaluated in light of clinical findings
  • Normally, the distance between the scaphoid and the lunate is < 3 mm in the frontal view

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