The normal dens occasionally can be posteriorly tilted and in such cases, can mimic a fractured, posteriorly tilted, dens. Differentiation of the two conditions depends on:  knowledge that this normal variation of the dens occurs, and  demonstrating that no fracture exists. In many cases, this latter determination can be accomplished on plain films, but in other cases, laminography is required.
Cervical spine Posteriorly tilted dens Dens Normal variation
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