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Updated: Oct 12, 2025

Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
Pterygospinous and pterygoalar bars in children
Kaan Esen1, Anıl Özgür2, Yüksel Balcı2
1Department of Radiology, Faculty of Medicine, Mersin University, Yenişehir, Mersin, Turkey. kaanessen@yahoo.com.
Purpose:
The formation of pterygoalar (Pa) and pterygospinous (Ps) bars are controversial whether they are secondary ossifications with aging or phylogenetic remnant. Therefore we aimed to evaluate the presence of Pa and Ps bars in children on routine cranial computed tomography images.
Methods:
We retrospectively analyzed the cranial computed tomography images of 500 children under the age of 18. Besides the 0.5 mm axial images, maximum intensity projection and 3D reconstructions were also used. The existence of incomplete or complete Pa and Ps bars were investigated.
Results:
Incomplete and complete Pa bar was detected in 4.6% and 2.2% of the cases, respectively. Incomplete Ps bar was seen in 13.6% of the cases and complete was in 6%. In total, per 1000 sides, 12 (2.4%) complete and 27 (5.4%) incomplete Pa bars were detected. In the same way, 35 (7%) complete and 88 (17.6%) incomplete Ps bars were seen. The smallest age ossification detected was 5 months old. Additionally, the prevalence of Pa and Ps bars between the under and over 10 years old age groups were statistically significant. Aging increased the prevalence.
Conclusion:
Considering our results, it seems that the ossification of Pa and Ps ligaments may not be solely related with aging.
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