Anatomical variations and elongation patterns of the styloid process: a computed tomography-based study

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 the SP in adult Saudis and to explore their associations with age and sex.

This retrospective study analyzed 152 cervical computed tomography (CT) scans obtained 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. SP elongation was defined as a length ≥ 30 mm. Statistical tests were performed to assess associations between demographic variables and anatomical parameters.

Elongated SPs (≥ 30 mm) were observed in 20% of 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 than women. Additionally, the left side demonstrated a greater transverse angle than the right. Aging showed weak but statistically significant correlations with SP length and orientation, suggesting potential progressive changes over time.

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 in patients with unexplained orofacial symptoms.