A meta-analytic review of the frequency and patterning of laryngohyoid and cervical fractures in cases of suicide by hanging

The frequency and distribution of fractures are commonly utilized to assist in interpreting the manner of death. In cases of alleged suicide by hanging, however, the evidence base for the frequency and patterning of laryngohyoid and cervical vertebrae fractures resulting from such blunt force traumatic events is limited and so fractures cannot be reliably used to assist in interpreting the manner. Using meta-analytic techniques, this study aimed to estimate frequency and distribution of fractures in the context of relevant intrinsic and extrinsic variables. A systematic review of the literature identified 20 studies with relevant data (8523 cases of suicide by hanging). Meta-analyses identified the frequency and distribution of fractures present and how fracture frequency was affected by the subgroups of age, sex, completeness of suspension, ligature knot position and study design. Results indicated that fracture frequency was variable, there was no unique patterning, and high levels of heterogeneity were present in all variable sub-groups. Age was the only subgroup to show differences. Findings suggest that neck fracture frequency is inconsistent and cannot be predicted by the chosen variables. Subsequently, neck fractures in isolation should not be given weight in medico-legal interpretations of a hanging death as suicidal.