Histologic appearance of fractured thyroid cartilage and surrounding tissues

Systematic review of laryngohyoid fractures in fatal falls: A potential mimicker of strangulation

Fractures of the laryngohyoid complex are classically associated with deaths due to strangulation. Recent studies, however, indicate the possible presence of such fractures in fatal falls. The primary focus of this systematic review is to analyze the characteristics of laryngohyoid fractures in the context of falls to aid in a more accurate interpretation of autopsy findings. Search for relevant literature occurred on PubMed on the 26th of October 2022, and Embase and Web of Science on the 5th of November 2022. Inclusion criteria included being a primary study, published in English, involving fatal falls and injuries to the laryngohyoid complex, and presenting sufficient details about the relevant cases. Four case reports and six descriptive retrospective studies were included in the final analysis yielding a sum of 38 cases. The risk of bias was assessed using the Joanna Briggs Institute (JBI) critical appraisal tools. Potential limitations of this study include the inclusion of case reports and studies published in English only. The cumulative male-to-female ratio was 23:15 with a mean age of 48 years old. The fall height ranged from standing height to 60 m. Forty-three fractures to the laryngohyoid complex were identified with the thyroid cartilage most commonly affected, followed by fracture of the hyoid bone, and finally the cricoid cartilage. While cases of falls did indeed display hallmark laryngohyoid findings classically displayed in strangulation, they also featured unique presentations such as fractures of the clavicle and a reduced prevalence of conjunctival petechiae.

Cartilage Tissue in Forensic Science—State of the Art and Future Research Directions

Cartilage tissue performs many functions in the human body. The diseases and injuries affecting it are prevalent due to its slow regeneration rate. However, cartilage tissue is exceptionally important for its auspicious use in forensic medicine due to its slow postmortem degradation rate. The presented review summarizes the latest research on cartilage tissues and their current and potential applications in forensic science. It also describes the most important studies on using cartilage and its microscopic and macroscopic analyses to estimate the deceased age and determine postmortem interval (PMI) values and the crime weapon. Additionally, the review describes attempts to isolate DNA from cartilage tissue for individual identification. The review also mentions recent, less abundant studies on the cartilage in forensic toxicology and genetics. It points out further directions and prospects for research development on cartilage tissue and its promising use in forensic medicine

Asphyxia homicides in Denmark 1992-2016

In this retrospective study , we present the findings in 250 homicides by asphyxia in Denmark in a 25-year period, with a particular focus on the autopsy findings in strangulation. Our intention is for the results to be used in future death investigations, where difficulties in interpretation of findings in potential asphyxial deaths arise. Asphyxia homicides showed a strong bias with respect to sex, age, and homicide type. The frequent female victim was typically an adult, whereas the rarer male victim was most often a child. Female offenders most often killed their children, and male offenders most often killed their female partner. Generally, most asphyxia homicides took place in a domestic setting. Manual strangulation and ligature strangulation were the most common mechanisms of asphyxia homicides (81.6%). A lack of petechial hemorrhages, especially in the conjunctiva, was rare in homicidal strangulation, but there were exceptions, especially when there was postmortem decomposition, making it impossible to verify them. Most victims of strangulation had skin lesions in the face (including the jawline) or on the neck, with accompanying hemorrhages in muscle and connective tissue, but the findings could be subtle or compounded by decomposition. Fractures of the laryngo-hyoid complex were common in strangulation, particularly in manual strangulation (chi-sq = 4.0993, df = 1, P < 0.05) and were clearly related to the age of the victim (chi-sq = 82.193, df = 4, P < 0.001). In children and young adults dying from homicidal strangulation, a lack of fractures is to be expected, while a lack of fractures is unusual, but not entirely unexpected, for adults and aged people.

Biomechanical study of the thyroid cartilage: A model of bi-digital strangulation

The presence of fracture on neck elements is an indication of violence. Both the hyoid bone and the larynx can be damaged by a strangulation mechanism. Thyroid cartilage, more specifically, may present lesions in response to this mechanical stress. These lesions result in fractures at the bases of the horns of the thyroid cartilage. This study focuses on the thyroid cartilage behavior in cases of bi-digital strangulation, using an anthropometric and biomechanical approach. To develop a biomechanical model, we performed an anthropometric study taking into account 14 distances measurements as well as 3 measurements of angles. These measures allowed us to determine a significant sexual dimorphism between individuals. Then, we define 6 morphologies models, composed of 3 females and 3 males individuals. In order to visualize the ossification of the cartilage, each model has been tested with bone properties. Strangulation cases were simulated by applying an imposed velocity of 0.4m/s then 1m/s. We observed different behaviors of the thyroid cartilage according to the sex and the morphology.

Pathology diagnosis of an atypical thyroid cartilage lesion

In forensic practice, laryngeal lesions are of particular interest for the pathologist, as they may sign foul play. We report the case of a decedent, whose body was found in an advanced state of putrefaction, at the bottom of a ledge, after a one-month disappearance. The face and neck were skeletised. The autopsy found multiple traumatic injuries. The hyoid bone was separated from the other laryngeal structures and seemed to be macroscopically normal. However, the thyroid cartilage had a thin notch at the base of the right upper horn. The nature of this notch was determined by microscopic examination: analysis showed incompletely ossified fibrous tissue, bordered by a line of enchondral ossification. We concluded that the notch was an old fracture, not concomitant with the polytrauma secondary to the fall that was the cause of death. This case shows that microscopic examination may allow the distinction between recent and old wound. Such a distinction is especially important in this context of polytrauma, where lesions could have been secondary to a fall, caused by a third party or unconnected with events.

Cervical Injuries in Drowning Cases: A Case Report and a Review of Literature

Discovery of bruises in the muscles of the neck and a fracture of the hyoid bone in a body recovered from water makes the diagnosis and the determination of the manner of death difficult.The aims of this work are to report a case of a drowned body with cervical injuries and to highlight the importance of interpreting these findings accurately.A 39-year-old woman was found dead face down in a 6-m deep well with a 3-m water level. She was mentally disturbed and had a history of suicide attempts. In fact, she had previously attempted to jump into that well in an attempt to put an end to her life. The autopsy revealed bruises in the muscles of the neck and a bruise associated with a fracture of the left horn of the hyoid bone.The mechanism for the origin of drowning-related neck injuries will be discussed.

The Laryngohyoid Complex in Medicolegal Death Investigations

The laryngohyoid complex, composed of the hyoid bone and laryngeal cartilages, can be of interest in the autopsy setting, particularly when injuries are observed. Analysis of trauma to this structure can assist in establishing cause and manner of death. In many situations, the forensic anthropologist, with their expertise in analyzing bone and cartilage trauma, can assist in analyzing trauma to this complex. Although researchers have tried to study the relationships between causes of trauma to the osseocartilaginous structure and the observed injury pattern, they have not been successful in identifying unique signatures associated with different causes of trauma. This is because different causes can result in the same or similar injury patterns. In addition, variation due to growth and development or due to remote injury may change the structure's biomechanical response. The goal of this paper is to address issues that a forensic pathologist may encounter when assessing potential trauma to the osseocartilaginous structures of the laryngohyoid complex; in particular, it focuses on anatomical variants and trauma resulting from various causes.

Micro computed tomography features of laryngeal fractures in a case of fatal manual strangulation

Cases of subtle fatal neck compression are often complicated by the lack of specificity of the post-mortem signs of asphyxia and by the lack of clear signs of neck compression. Herein we present a forensic case of a 45-year-old schizophrenic patient found on the floor of the bedroom of a psychiatric ward in cardiopulmonary arrest and who died after two days in a vegetative state. The deposition of the roommate of the deceased, who claimed responsibility for the killing of the victim by neck compression, was considered unreliable by the prosecutor. Autopsy, toxicological analyses, and multi-slice computed tomography (MSCT), micro computed tomography (micro-CT) and histology of the larynx complex were performed. Particularly, micro-CT analysis of the thyroid cartilage revealed the bilateral presence of ossified triticeous cartilages and the complete fragmentation of the right superior horn of the thyroid, but it additionally demonstrated a fracture on the contralateral superior horns, which was not clearly diagnosable at MSCT. On the basis of the evidence of intracartilaginous laryngeal hemorrhages and bilateral microfracture at the base of the superior horns of the larynx, the death was classified as a case of asphyxia due to manual strangulation. Micro-CT was confirmed as a useful tool in cases of subtle fatal neck compression, for the detection of minute laryngeal cartilage fractures, especially in complex cases with equivocal findings on MSCT.

Causes of laryngeal cartilage and hyoid bone fractures found at postmortem

The principal aims of this retrospective study were to assess the prevalence and causes of laryngo-hyoid fractures found in coroners' adult postmortem examinations over a five-year period. In 78 of 1930 cases (4%), there was a fracture of the larynx (thyroid or cricoid cartilage) or hyoid bone. The thyroid cartilage alone was fractured in 38 cases; the hyoid bone alone was fractured in 19 cases; the larynx and hyoid bone were both fractured in 21 cases, including one which involved the cricoid cartilage. There was no evidence of surface injury to the neck in 14.1% of cases. The majority (44/78; 56.4%) involved classical manual or ligature 'pressure to the neck', i.e. hanging (32) or strangulation (12) but a significant minority (35.9%) involved other circumstances: road/rail traffic collision (12; 15.4%); falls (6; 7.7%); assaults involving blunt force trauma to the head and neck (4; 5.1%); incised wounds (3; 3.8%); gunshot wounds (2; 2.6%); and explosion (1; 1.3%). The circumstances of death and cause of fracture(s) were 'unascertained' in four cases (5.1%). Postmortem artefact accounted for two cases (2.6%).

Hyoid-laryngeal fractures in hanging: where was the knot in the noose?

The aims of this study were to determine the frequency of hyoid-laryngeal fractures in hanging in relation to the position of the ligature knot, to reconstruct the location of the ligature knot in cases of hanging when the furrow is not detectable on the skin, and to identify the possible mechanism of neck structure injuries. We report a retrospective autopsy study which included 557 cases of suicidal hanging: 413 men and 144 women, with an average age of 52.4 +/- 17.8 years. In 57.3% of them, hyoid-laryngeal fractures were found (average age was 54.3 +/- 16.5 years): 15.1% had only hyoid bone fracture, 26% had only thyroid cartilage fracture and 16.2% had both types of injury at the same time. Hyoid-laryngeal fractures were found more often in persons aged over 30 years. Hyoid bone fracture was a weak predictor of ligature knot position in our sample. Fracture frequencies of the thyroid cartilage show a statistically significant difference in relation to the ligature knot position among persons older than 30 years, which indicated the ipsilateral and posterior position of the knot. Absence or presence of any form of hyoid-laryngeal fracture indicated that knot position was anterior or posterior, respectively. The derived data would be useful for cases where the ligature has been removed from the body of the deceased shortly after hanging, where the noose is unavailable, and in cases where the ligature mark has faded such as with soft ligatures removed promptly or in decomposed bodies.

Asphyxial Deaths

An increasing death rate as a result of violence constitutes a large group in medicolegal autopsies. Specially, deaths due to asphyxia are one of the most important causes in violence deaths. During the 21-year period from January 1984 to October 2004, there were 134 asphyxial deaths autopsied by the Department of Forensic Medicine, Trakya University, Edirne, Turkey. Asphyxial deaths comprise 15.7% of all forensic autopsies; 20.8% of the cases are aged between 30 and 39 years, and the average age was 41.9 years. Males constitute 79.8% of all the cases. The most frequent method of asphyxiation death is hanging (56 cases, 41.8%), followed by drowning (30.5%) and carbon monoxide poisoning (8.2%). More violent methods, such as ligature or manual strangulations, constitute 2.9% and 2.3% of all asphyxial deaths, respectively. Although it was varying according to the methods of asphyxiation, suicide was found to be the manner of death in the majority of the cases.

Laryngohyoid fractures after agonal falls: Not always a certain sign of strangulation

Haemorrhagic fractures of the thyroid cartilage and hyoid bone are frequently observed in cases of strangulation and often regarded as evidence for an assault against the neck. In contrast, two cases of laryngohyoid fractures after agonal falls in prone position are presented to draw attention to alternative causes of these injuries with special regard to practical medicolegal casework. A 45-year-old man collapsed at a fairground and died after unsuccessful resuscitation. He showed excoriations at his elbows and right knee, a crush injury at the mentum and his mandibular front teeth were knocked out. The upper parts of the chest and the head showed blue discolouration as a marked sign of congestion due to heart failure. The right coronary artery (RCA) was completely obturated by a 5 cm long post-stenotic thrombus with subsequent myocardial infarction of the lateral part of the left ventricle. Both superior horns of the thyroid cartilage were fractured with surrounding haemorrhage, the skin and muscles of the neck uninjured. In the second case, a 63-year-old woman with a mobility handicap had fallen from a 2m high lifting platform and was found in prone position with her wheelchair on her. Resuscitation efforts were not successful. Autopsy showed signs of blunt external force against head, neck, chest and limbs. Examination of the neck revealed haemorrhage of the right sternocleidomastoid muscle, both superior horns of the thyroid cartilage were fractured, as well as the hyoid bone, with slight haemorrhage of the surrounding soft tissue and mucosa. On the same level, the fifth intervertebral disk was ruptured, without any injury of the spinal cord. These cases demonstrate that laryngohyoid fractures should not be overestimated as unequivocal indication of neck compression and may well be caused by falls, even at ground level.