Morphometric variations of the pterion among skulls at the Galloway Osteological Collection in the Department of Human Anatomy Makerere University

Abstract

Background: The pterion is an important anatomical land mark in neuro surgery, it’s also important in Forensic examination of the human skull, to anatomists when teaching undergraduate medical students and postgraduates as well as in radiology. There are however variations of this structure by ethnicity or nationality, age and sex. Although pterion morphology has been examined in various settings, the same is limited in Uganda. Therefore, this study wascarried out to examine the different pterion morphological variations among the skulls at the Galloway osteological collection, Department of Anatomy, College of Health Sciences, Makerere University. Methods: This was a descriptive cross-sectional study which used 65 skulls including 73.8% males. These skulls were examined fortype of pterion and the distance from the center of pterion to mid zygomatic arch and frontozygomatic suture determined using a digital Vernier caliperat the Department of Anatomy, Makerere University. All the distances measured were assessed using the Welch t-test and two sample t-test. Data analysis was done using R version 4.1.1 for windows. Findings: Sphenoparietal type of pterion was the commonest 65.4%. The distance from pterion to zygomatic arch and frontozygomatic suture showed variations with age and nationality. The Ugandan nationality showed to have a slightly higher pterion from the zygomatic arch 33.5mm± 5.13 on the left and 34.7mm± 4.48 on the right side of the skull than the non-Ugandan skulls, whereas looking at the distance of pterion to frontozygomatic suture the non-Ugandan showed to have a greater distance of 26.02mm ± 4.88 on the left side of the skull compared to the Ugandan skulls but equal distances on the right side of the skull. The observed differences were however not statistically significant. Conclusion and recommendations: Pterion variations were observed in the specimens of the Ugandan and Non-Ugandan skulls, therefore it’s important for clinicians to be aware of them for accuracy in determining the exact point for burr-hole positioning while performing craniotomy.