String sign (bones)

Last revised by Mohammad Taghi Niknejad on 25 Aug 2024

The string sign of parosteal osteosarcoma refers to a radiolucent cleavage plane between portions of the tumor and cortex of the affected bone in more than 50% of cases 2, better visualized on CT rather than on a radiograph. The tumor stalk becomes more broad-based with time, obliterating the string sign in later stages.

The string sign can also be seen in myositis ossificans.

Cases and figures

  • Case 1
  • Case 2
:

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.