The Dens-Arch synchondrosis versus the Hangman's fracture.

The synchondrosis between the dens and arch of C2 is a normal structure in infants and children. It is not visible on lateral views of the cervical spine, but is routinely visible on oblique views. In such cases it has a distinct tendency to mimic a C2-arch fracture. The varying appearance of this synchondrosis and its differentiation from a true fracture of C2 are the subjects of this report.