Fig. 2.
A positive jigsaw sign in a typical case of os odontoideum. Note the interdigitation and narrowing of the atlanto-axial joint line. The arch-peg-area ratio is elevated
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.