A new superficial landmark for the odontoid process: a cadaveric study.

Document Type


Publication Date


Publication Title

Anatomical science international / Japanese Association of Anatomists


Aged; Aged, 80 and over; Cadaver; Female; Humans; Lip; Male; Odontoid Process; Radiography; Anatomy; Axis; Cervical spine; Landmarks; Odontoid process; Philtrum


When image guidance is not available or when there is a need to confirm the findings of such technology, superficial landmarks can still play a role in providing surgeons with estimations of the position of deeper anatomical structures. To our knowledge, surface landmarks for the position of the odontoid process have not been investigated. We have therefore performed an anatomical study to investigate such a landmark. One-centimeter metallic rods were placed on the philtrum of the upper lip of 20 cadaveric head specimens. To assess the position relative to the odontoid process, we took lateral and anteroposterior radiographs and recorded the measurements. Descriptive findings from radiographic observations indicated a reasonable approximation between the philtrum and the midpoint of the odontoid process. Based on our results, we suggest that the philtrum of the upper lip can serve as a first line estimation of the position of the odontoid process and can assist in verifying this bony structure following the use of image guidance.

Clinical Institute

Neurosciences (Brain & Spine)




Pathology & Laboratory Medicine