Exploring the prevalence and impact on craniocervical spine surgery of ponticulus posticus on atlas lamina thickness.

Background and objectives: Ponticulus posticus (PP), also known as arcuate foramen or Kimmerle's anomaly, is an atlas (C1) bone anomaly in the form of a bone bridge. This study aims to determine the prevalence of PP in two hospitals in Surabaya, Indonesia, and to determine the risk factors for PP and its impact on the thickness of the C1 lamina.

Materials and methods: We conducted a retrospective analysis using a total sampling technique of computed tomography scan results from 121 patients at Dr. Soetomo Surabaya Hospital's and Mitra Keluarga Surabaya Hospital's Department of Neurosurgery. The study included patients aged 18 and aging who met the inclusion criteria. We assessed the relationship between C1 morphological characteristics and PP prevalence, with particular focus on laminar thickness measurements.

Results: The study found a prevalence of PP of 15.7%. The mean thickness of the posterior arch lamina with PP was 3.3 ± 0.95 mm on the right side and 3.4 ± 1.0 mm on the left side. Although these figures are not statistically significant, both were thinner than the lamina without PP. The study also found that the prevalence of PP increases with age, with a significant value of P < 0.001.

Conclusions: The average thickness of the posterior lamina arch containing PP has a smaller value but is not statistically significant. In this study, significant statistical results were obtained to suggest that the prevalence of PP increases with age (degenerative).