Anatomical variations and elongation patterns of the styloid process: a CT-based study.

Abstract

Background: Elongation of the styloid process (SP) can impinge on adjacent neurovascular structures, provoking Eagle's syndrome. This study aimed to assess the length, angulation, and morphology of SP in adult Saudis and to explore their associations with age and sex.

Materials and methods: A retrospective analysis of 152 cervical computed tomography (CT) scans at a tertiary hospital in Riyadh. Participants were ≥ 25 years old (76 men, 76 women). Bilateral SP length, sagittal and transverse deviation angles, and morphology were recorded. Elongation of SP was defined as length ≥ 30 mm. Statistical tests were performed to assess associations between demographic variables and anatomical parameters.

Results: Elongated SPs (≥ 30 mm) were observed in 20% of the cases, with no significant differences between sexes or sides. The most common morphology identified was the uninterrupted elongated type (72%), followed by pseudo-articulated (21%) and segmented (7%). Elongation was more frequently associated with the pseudo-articulated and segmented forms. Although sex did not influence the rates of elongation, men showed longer SPs and greater sagittal deviation angles compared to women. Additionally, the left side demonstrated a higher transverse angle than the right. Aging was shown to have a weak, statistically significant correlation with SP length and orientation, suggesting potential progressive changes over time.

Conclusions: The findings of this study indicate a notable prevalence of elongated SPs in the Saudi population and highlight specific anatomical features that may contribute to Eagle's syndrome. These results underscore the diagnostic value of CT imaging for patients with unexplained orofacial symptoms.