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Case of the Week 376

What's the name of this sign?

  • 78 year-old male who fell off ladder

Frontal and lateral radiographs of femur

1. Signet sign
2. Rat-bite sign
3. Blade-of-grass sign
4. Crescent sign
5. Ring sign

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3. Blade-of-Grass Sign



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Blade-of-Grass Sign

 General Considerations

  • V-spaded lucency in the metadiaphysis, usually seen in a long bone and representing the lytic phase of Paget disease
  • Most often seen in femur and tibia
  • In the skull, the lytic defect is referred to as osteoporosis circumscripta, most often seen in the frontal bone

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