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Updated: Jan 9, 2026

Author Spotlight: Three-Dimensional Cephalometric Landmark Annotation Demonstration on Human Cone Beam Computed Tomography Scans
Published on: September 8, 2023
Documenting precondylar tubercles and third occipital condyles in human crania from a museological collection (Rome,
Aleksandra Gawlikowska-Sroka1, Jacek Szczurowski2, Ileana Micarelli3
1Department of Anatomy, Pomeranian Medical University, Szczecin, Poland. aleksandra.gawlikowska.sroka@pum.edu.pl.
Background:
Anatomical variants such as the precondylar tubercle (PCT) and third occipital condyle (TOC) are rare bony projections located at the anterior margin of the foramen magnum. Though often asymptomatic, they can have clinical relevance in radiological and surgical contexts. Despite growing interest in these traits, their presence in European skeletal collections remains poorly documented.
Materials And Methods:
This study examined 126 crania from the historical collection curated at the Museum of Anthropology "Giuseppe Sergi" (MGS), Sapienza University of Rome. Biological profiles were reassessed using standard anthropological methods for sex determination and age estimation. Macroscopic evaluation focused on the presence of PCT and TOC, as well as associated traits such as bipartite hypoglossal canals.
Results And Discussion:
Eight crania presented PCTs; of these, two also exhibited TOC. In the latter specimens, the absence of postmortem damage allowed confident exclusion of fusion with the atlas or axis, suggesting an incidental occurrence and likely asymptomatic condition. Two specimens with PCT also displayed bipartite hypoglossal canals. Although the sample does not represent a population in the proper sense, these findings align with previously reported frequencies in modern collections and highlight potential developmental origins shared between PCT and TOC.
Conclusions:
The identification of PCT and TOC in a curated historical sample contributes to the documentation of rare morphological variants at the craniovertebral junction. These results underscore the relevance of skeletal collections in descriptive anatomy and support future multidisciplinary research integrating clinical, developmental, and evolutionary perspectives.
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