Histologic appearance of fractured thyroid cartilage and surrounding tissues.

Histological appearances of the fractured superior horns (SH) of the thyroid cartilage and their surrounding tissues were reviewed, with particular reference to signs of vital origin of the fracture. Twenty-nine autopsies with either histories or findings indicating asphyxial neck compression, with a total of 39 fractured SHs, and three autopsies with history of suicidal jump from height with a total of two SH fractures, were examined. Fifteen autopsies with finding of 19 artefactually fractured SHs while removing neck organs at autopsy were used as controls. In the cases of neck compression and victims of jump from height haemorrhages, retraction of fractured SH fragments with invagination or squeezing of the perichondrium, contraction bands, contraction band necrosis and 'opaque fibres', in the adjacent muscle fibres could be seen. Fibrin deposition and/or leucocytic reaction were noted in cases where circumstances of death indicated prolonged death struggle (as in incomplete hanging, resuscitation or homicidal neck compression). However, retraction of fractured fragments and invagination of perichondrium between artefactually fractured SH fragments were observed in both control cases and cases with antemortem trauma to the larynx. Many of these histological findings, including haemorrhages and fractures had not been evident at gross examination. We conclude that histological examination of SHs may not only uncover macroscopically overlooked injuries but also may facilitate the clarification of an injury's vital origin.