Occipital bone thickness: Implications on occipital-cervical fusion. A cadaveric study

Abstract

Objective: The aim of this study was to create a map of the occipital bone using a cadaveric morphometric analysis. Material: Twelve heads, from seven male and five female cadavers, were studied. The thickness of the occipital bone was measured with a digital vernier caliper within a coordinate system. Results: The maximum thickness of the occipital bone could be measured at the external occipital protuberance (mean 15.4 mm; range 9–29.3 mm). All male individuals had higher bone thickness around this point. Further lateral a steady decrease of bone thickness could be observed. Same could be observed in craniocaudal direction. However, values above the superior nuchal line were on average thicker than below. Conclusion: The measurements demonstrated a great individual variability of bone thickness of the occipital bone. The results emphasize the role of preoperative planning for the feasibility of placement of an occipital screw. Keywords: Occipital bone thickness, Occipital-cervical junction, Occipital bone, Occipital-cervical fusion