Biomechanics of a previously unknown thyroid cartilage fracture in fatal strangulation

Abstract

After the death of a 63-year-old woman following pressure against the neck, the injury was assessed forensically and a radiological-preparatory examination of the osseous structure of the larynx was conducted. We used fine preparation and, for further characterization of the fracture, radiological imaging in spiral CT, 3D reconstruction and fine-focus technique (mammography). While a skeletal injury with the basal fractures of the upper horns of the thyroid cartilage was clearly visible in the CT and 3D reconstruction, the radiological visualization of a 3-4mm wide wall-penetrating dehiscence in the upper part of the thyroid cartilage commissure required a higher sensitivity. Using fine-focus technology, we were able to diagnose this fracture as an avulsion of the cartilage from the medial primary ossification center of the thyroid cartilage. Not only has this type of fracture of an insertion avulsion of the median thyrohyoid ligament never been described before, but it must also be considered as the main fracture in dorsocranial traction. In this specific case, it enabled the expert to state in court that strangulation had occurred from behind.