Upward displacement of the odontoid process into the foramen magnum: a palaeopathological case.

An upward displacement of the odontoid process into the foramen magnum was observed in the skeletal remains of a young male unearthed from a 14th to 17th century cemetery in the north-eastern Italy. Examination of skull bone vestiges and computed tomography scan analysis of the axis exhibited a clear-cut contact zone between the odontoid process and the anterior border of the foramen magnum. In addition, the odontoid process appeared backward deviated. Findings suggest a possible diagnosis of basilar impression/invagination. This anomalous contact may cause compression of neural and vascular structures with a multifaceted series of clinical symptoms. We are unable to set our finding into a complete presumptive diagnostic outline because there is no chance to estimate either the magnitude of the whole craniovertebral junction defect but we believe that the present case contributes to the general knowledge of the craniovertebral region and to bone pathology in ancient times.