Factors associated with thyrohyoid injuries in hanging cases: An autopsy study in North Africa

Hanging is the most frequent method of suicide in Tunisia. Its medico-legal assessment requires an integrated approach combining the circumstances of death, scene investigation, and complete postmortem examination to establish the cause and manner of death and assess possible third-party involvement. Among the internal findings, injuries of the hyoid-laryngeal complex are of particular medico-legal interest, although the factors associated with their occurrence remain incompletely understood.

This study aimed to identify factors associated with thyrohyoid fractures in hanging deaths and to determine which factors remained independently associated with these injuries after multivariate analysis.

This retrospective analytical study included all cases of mechanical asphyxia by hanging autopsied at the Department of Forensic Medicine, University Hospital Sfax, between January 2020 and December 2022. Socio-demographic data, death circumstances, external examination findings, and autopsy results were collected. Univariate and multivariate logistic regression were used to identify predictors of thyrohyoid fractures.

Seventy-nine cases were included (mean age 39.9 ± 19.2 years, range 3-88; 79.7% male). Most deaths occurred at home (74.7%) and during winter (35.4%). Complete hanging accounted for 45.6% and narrow ligatures for 46.8%. Cervical soft-tissue hemorrhages were observed in 65.8%, while thyrohyoid fractures occurred in 35.5% of cases. Univariate analysis showed significant associations with age >40 years (OR 3.5; p = 0.006), weight >75 kg (OR 3.1; p = 0.010), complete hanging (OR 10.2; p < 0.001), and narrow ligatures (OR 4.4; p = 0.004). Multivariate analysis confirmed complete hanging (OR 43.4; p < 0.001) and age >40 years (OR 5.3; p = 0.043) as independent predictors.

Thyrohyoid fractures in hanging were associated with both demographic and hanging-related factors. After multivariate analysis, age >40 years and complete hanging remained independently associated with these injuries. These findings may provide useful contextual information when interpreting thyrohyoid fractures but should be considered alongside the circumstances of death and complete autopsy findings.