Prevalence and Morphological Classification of Persistent Metopic Suture in Adult Autopsy Cases: A Forensic...

Background: Persistent metopic suture represents a normal anatomical variant that may persist into adulthood and can be misinterpreted as a frontal skull fracture, particularly in trauma-related forensic cases. Despite its clinical and medico-legal relevance, data derived from autopsy-based evaluations remain limited, with most prevalence studies relying on dry skull collections or radiological series. This study aimed to determine the prevalence and morphological characteristics of persistent metopic suture in adult autopsy cases and to evaluate its distribution according to age, sex, and cause of death. Methods: This cross-sectional study included 500 consecutive adult autopsy cases (≥18 years). The frontal bone was directly inspected during autopsy for the presence of metopic suture, which was classified as complete or incomplete. Descriptive statistics were applied, and associations between metopism and sex, age group, and cause of death were analyzed using chi-square or Fisher's exact test, as appropriate. Results: Complete metopism was identified in 7 of 500 cases, corresponding to a prevalence of 1.4% (95% confidence interval: approximately 0.6-2.9%). No incomplete metopic sutures were observed. Metopism was slightly more frequent in females than males; however, no statistically significant association was found between metopism and sex, age group, or cause of death (p > 0.05). Conclusions: Persistent metopic suture is an uncommon but clinically and forensically relevant anatomical variant in adults. Its recognition during forensic autopsy is essential to avoid misinterpretation as a cranial fracture, particularly in trauma-related deaths, thereby preventing diagnostic and medico-legal errors.