Ballistic long bone fracture pattern: an experimental study.

When dealing with badly preserved cadavers or skeletal human remains, the assessment of death circumstances remains challenging. When forensic evidence cannot be taken from the skin and soft tissue, the information may only be deduced from more resistant elements such as bone. Compared to cranial gunshot injuries, reliable data on ballistic long bone trauma remains scarce. This study aims to define ballistic fracture characteristics in human long bones. The shaft of 16 femurs and 13 humeri from body donors was perpendicularly shot with a 9-mm Luger full metal jacket bullet at an impact velocity of 360 m/s from a distance of 2 m. Some bones were embedded in Clear Ballistics Gel®, and some were shot without soft tissue simulant in order to better visualise the fracture propagation on the high-speed camera. The fractures were examined macroscopically and compared between the sample groups. We consistently found comminuted fractures with a stellate pattern. Fracture details were classified into entrance, exit and general characteristics. For some traits, we detected different occurrence values in the group comparison. The results indicate that some of the traits depend on bone properties such as shaft diameter, bone length and cortical thickness. The presence of ballistic gel also influenced some fracture traits, emphasising the relevance of soft tissue simulant in osseous gunshot experiments. This study revealed new insights in the detailed fracture pattern of human long bones. These may serve as guidelines for the identification and reconstruction of gunshot trauma in human long bones.

Investigating reverse butterfly fractures: An experimental approach and application of fractography.

Butterfly fractures are expected to form with the transverse portion on the tension side and the wedge portion on the compression side of a bent bone, however wedges have also been observed in the reverse orientation and are reported to be frequent in concentrated 4-point bending. To investigate how these fractures form, concentrated 4-point bending experiments were performed on nine human femora and documented using high-speed video. Videos showed the wedge portion formed as fracture initiated in tension, branched obliquely, then curved to terminate on the tension face. The transverse portion formed as a crack traveled between the curved fracture branch and the compression face. Fractography was also applied to evaluate fracture surfaces. At least one fractography feature was present in all femora and 32/35 bone fragments examined. Fracture propagation sequences interpreted using fractography matched those observed on video, demonstrating the utility of this method for evaluating complex fracture patterns.

Experience in surgical treatment of type â ¡ odontoid fractures: A report of two cases and review of the literature.

Two cases of type Ⅱ odontoid fractures were reported to share our experience in surgery treatment of such cases. A 33-year-old woman with comminuted type Ⅱ odontoid fracture and a 42-year-old man with fracture end hardened type Ⅱ odontoid fracture received surgical treatment in our hospital. Though imaging examination suggested that these two patients were suitable for anterior screw fixation, we encountered difficulties during the operation. The two patients eventually underwent posterior C1-C2 fusion surgery and recovered well. According to the experience of these two cases, we found that the fracture line angle and the degree of comminution are two important factors affecting surgical decision-making. Although anterior screw fixation is the ideal choice for type Ⅱ odontoid fractures with anterior superior to posterior inferior fracture line, it may not be the best choice for comminuted or fracture end hardened type Ⅱ odontoid fractures.

Dislocation of Internal Organs of the Neck and Trunk Into Crush Injuries of the Head: Case Report on a Truck-to-Pedestrian Accident.

The authors report on a case of a 43-year-old male pedestrian struck and run over by a truck. The accident was accompanied by a mechanism of injury resulting in a unique autopsy picture of trunk and head injuries. The internal organs of the neck (larynx, trachea, esophagus), chest (lungs, thoracic aorta), and part of the abdominal cavity (bottom of the stomach and fragments of the liver) were dislocated in the direction of the head. The result was a traumatically deformed, crushed skull characterized by an extensive gaping wound with excerebration. The organs were dislocated through a channel formed by the rupture of soft tissues and comminuted fracture of the base of the skull. Parts of internal organs (larynx, trachea, and aorta) were turned 180° around the transverse axis of the body. This report, due to its unusual character, may be useful during detailed analysis of potential injury mechanisms in traffic accidents involving pedestrians.

Prolonged Electro-muscular Incapacitation in a Porcine Model Causes Spinal Injury.

Conducted electrical weapons are designed to cause temporary electro-muscular incapacitation (EMI) without significant injury. The objective of this study was to assess the risk and cause of spinal injury due to exposure to a benchtop EMI device. Porcine subjects were exposed to 19 and 40 Hz electrical stimuli for a prolonged duration of 30 sec. X-ray imaging, necropsy, and accelerometry found that lumbosacral spinal fractures occurred in at least 89% of all subjects, regardless of the stimulus group, and were likely caused by musculoskeletal fatigue-related stress in the lumbosacral spine. Spinal fractures occurred in the porcine model at an unusually high rate compared to human. This may be due to both the prolonged duration of electrical stimulation and significant musculoskeletal differences between humans and pigs, which suggests that the porcine model is not a good model of EMI-induced spinal fracture in humans.

Differentiation between perimortem trauma and heat-induced damage: the use of perimortem traits on burnt long bones.

Burnt human remains present a difficult interpretative dilemma to forensic pathologists and anthropologists. Distinguishing postmortem damage in long bones as a result of fire damage from perimortem fractures is an important challenge in trauma analysis. During our case investigation of a burnt body from a fiery car crash, distinct perimortem traits on long bone fractures were still distinguishable along the charred areas. Next to timing of fractures and shortening the perimortem time gap suggesting that the fractures occurred when soft tissue was still present, the traits make it possible to distinguish blunt trauma caused by the accident from heat-induced bone damage. Applying this specific perimortem pattern could be an additional macroscopic tool to interpret blunt force trauma more accurately in the analysis of burnt remains.

Axe injury pattern in homicide.

Chop or slash wounds are produced by sharp-edged tools such as an axe, or a machete. This paper presents a case of a violent death of a 57 year-old-man. Autopsy revealed deformation of the right side of the head. A total of 23 slash, stab and cut wounds as well as contused lacerations were identified on the scalp as well as the face and the neck. In addition, superficial abrasions and bruises were identified on the skin. The immediate cause of death was due to extensive brain contusion following fragmentation of the neurocranium. The injuries resulting in the death of the victim were sustained during an assault on the head with an axe, which was used both as a slashing tool and a blunt instrument.

Use of surgical glue for Mason type III radial head fractures: A case report.

RATIONALE: A Mason type III radial head fracture, which is characterized by comminuted fragments of the radial head, is a severe injury. Open reduction and internal fixation (ORIF) is an alternative treatment method; however, the technique of using an on-table reduction in combination with surgical glue is rarely reported. PATIENT CONCERNS: A 48-year-old man was admitted to our department with complaints of elbow pain after falling down. Elbow radiography and computed tomography (CT) demonstrated characteristics of fractures before the operation. DIAGNOSIS: Radiographic images showed a Mason type III radial head fracture. INTERVENTIONS: The patient underwent ORIF at our hospital. During the operation, the technique of on-table reconstruction combined with surgical glue was used. OUTCOMES: The patient recovered well and was able to participate in his usual work. LESSONS: Mason type III radial head fractures could be treated with ORIF, and a satisfactory result could be anticipated, thus avoiding a radial head replacement or resection. Anatomical reduction of a comminuted radial head could be obtained via an on-table reconstruction and application of surgical glue.

A month in a horse's life: healing process of a fractured third metatarsal bone from medieval Viljandi, Estonia.

The remains of a horse's hind foot - a third metatarsal bone and three phalanges - were found in a presumed waste pit of a prosperous medieval household in Viljandi, Estonia, dated from the second half of the 13th to the beginning of the 15th century. The metatarsal bone had been broken during the horse's lifetime and showed evidence of partial healing. Using archaeological, zooarchaeological, morphological, microscopic, densitometric and radiographic analyses, we investigated the bones and the healing process in order to understand animal treatment in a medieval urban context. Our results show that the fracture was a complete comminuted fracture that appears to have been closed and stable, caused most probably by a trauma from a strong impact. Based on callus formation and the worn edges of the separated diaphysis, the horse had survived for at least a month and used the injured foot to some extent. We suggest that the horse was treated by splinting the foot and keeping the animal in a standing position during the healing process. Eventually the horse died because of a wound infection, or was killed. The relatively long period of careful treatment indicates the animal's economic or emotional value.

Application of Platelet-rich Plasma and Tricalcium Phosphate in the Treatment of Comminuted Fractures in Animals.

AIM: To assess the applicability of ß-tri-calcium phosphate (TCP) and platelet-rich plasma (PRP) in the treatment of comminuted fractures in small animals. MATERIAL AND METHODS: The experimental study was carried out on 16 New Zealand White rabbits. After creating the bone defect and performing tibial osteotomy, TCP implants containing activated PRP were introduced into the fracture and the defect. The fracture was stabilised using external fixators or intramedullary nails. After 12 weeks, the animals were euthanised, and radiological, histological, scanning electron microscopy and peripheral quantitative computed tomography examinations were performed. The analysis also covered the results of fracture treatment in 37 small animals (cats and dogs) in which treatment with TCP containing PRP was used as an alternative to cancellous bone implantation. RESULTS: Correct bone union was observed in the experimental groups, TCP remained visible at the site of the fracture after 12 weeks. In the clinical application in small animals, bone union was observed in over 91% of treated animals. CONCLUSION: ß-TCP and activated PRP may be an effective method of bone union enhancement in the treatment of comminuted fractures in small animals.

Fatal Transorbital Intracranial Penetrating Injury Due to a Bicycle Brake Handle.

Transorbital intracranial injuries are uncommon and mostly accidental in nature. These injuries are usually associated with high mortality. The key to preventing this mortality involves an early diagnosis of intracranial injuries and immediate and appropriate management. Any delay can pose a serious risk to the patient's life. A case of a 55-year-old man who had experienced an accidental self-fall while riding a bicycle is presented. Initially, he was treated at a primary health center. He was referred to the tertiary care institute due to unavailability of ancillary investigation at the primary health center. He was declared dead on arrival at the casualty in the tertiary institute. On autopsy, it was observed that the injury above the right side of the upper eyelid was penetrating the right side roof of the orbit and the right cerebral cortex and brainstem. The highlighting feature of the case is that, despite the fatal penetrating brain injury, the eyeball did not sustain any major injury.

Mapping of 238 quadrilateral plate fractures with three-dimensional computed tomography.

PURPOSE: The primary goal of this study is to create a frequency map of a series of the quadrilateral plate fractures, explore the characteristics of fracture map and to further propose a new classification. METHODS: We used a consecutive series of 238 quadrilateral plate fractures to create 3-dimensional reconstruction images, which were superimposed and oriented to fit a model hemipelvis template by aligning specific pelvis landmarks. Fracture lines were identified and traced to create a quadrilateral plate fracture map. RESULTS: Fracture location corresponded with fracture line distribution. Of 238 fractures that met the criteria for inclusion, most fractures involved the "A + B" zone (n = 156; 65%), whereas the remaining minority of the fractures involved the "A" zone (n = 59; 25%) and the "B" zone (n = 23; 10%). Correspondingly the incidence of C-type fracture ("A + B"zone) was significantly higher than that of A-type fracture and B-type fracture. Additionally the most common pattern was demonstrated by coexisting fracture lines; nearly half (48%) of the fractures involved the upper section of the quadrilateral plate traversing both zones, 46% traced almost vertically to the arcuate line, and 25% extended to the posterior aspect. Furthermore, the high fracture line intensity (n = 172; 74%) formed a Gun-shaped pattern, which pointed to the ischial tuberosity. CONCLUSIONS: The map shows that the comminution is prone to traverse the quadrilateral plate in the sagittal direction among nearly two-thirds of all fractures. Moreover, Surgically treated quadrilateral plate fractures display very common patterns. The most common pattern is the upper fracture in nearly half of the fractures. Knowledge of these patterns can aid surgeons during diagnosis, preoperative planning, and execution of surgical strategies.

Autopsy Features of Fatal Donkey Attack.

Lethal donkey attacks have very rarely been described. The case of a 65-year-old man who was found deceased on a country road with 2 domestic donkeys nearby is, therefore, reported. Examination of the body revealed contusions and lacerations of the face and scalp, a comminuted fracture of the left maxilla, comminuted fracturing of the right radius and ulna and of the left anterior superior iliac spine, a flail chest, and pulmonary contusions. In addition, there were bite marks on the left thigh, right buttock, right axilla/upper arm, and left cheek which corresponded to the dental arcades of the donkeys. Death had resulted from blunt chest trauma due to an attack by 1 or 2 donkeys. Deaths and serious injuries are much more commonly caused by horses; however, this case shows that even domesticated donkeys may also rarely be capable of inflicting significant trauma and so should be approached with circumspection.

[Surgical stabilization of multiple rib fractures can shorten inpatient stay].

Flail chest is a common complication in patients with blunt chest wall traumas resulting in high mortality rates. In this case report a 43-year-old woman was stepped on by a horse, thereby receiving multiple rib fractures and pneumohaemothorax. She was not able to wean from epidural analgesia after ten days and maintained a "thoracic floating feeling". In opposition to the non-operative management previously preferred, a surgical stabilization was then performed in the patient, who was discharged only five days later. Thus, surgical fixation of multiple rib fractures may reduce inpatient stay.

Suicide in parachuting: A case report and review of the literature.

Skydiving fatalities are mostly accidental and the result of human errors. However, suicides may be greatly underreported in skydivers. We present the case of a young civilian skydiver who committed suicide by jumping from an altitude of 4000m without activating his chutes. Witnesses reported that the victim had remained in a freefall position until ground impact. Besides an extensive blunt trauma, the autopsy showed an antero-posterior flattening of the body with symmetrical abrasions on its front, which were consistent with a high-energy impact on the ground in a "belly-down" position. Police investigation revealed that the victim had expressed suicidal thoughts in text messages before jumping from the airplane, and examination of his equipment showed that he had disabled the security system allowing the reserve chute to be automatically deployed at low altitude. To the best of our knowledge, this is the first case of suicide of a skydiver that has been described in the scientific literature. A suicidal intent should be assumed in skydiving fatalities involving jumpers with operable but un-activated parachutes on their back. This case highlights the importance of a thorough forensic investigation in such circumstances to ascertain the manner of death.

The Accuracy and Applicability of 3D Modeling and Printing Blunt Force Cranial Injuries.

The purpose of this study was to determine the factors affecting the accuracy of 3D models and 3D prints of cranial blunt force trauma, to evaluate the applicability and limitations of modeling such injuries. Three types of cranial blunt force lesions were documented (hinge, depressed, and comminuted) using three forms of surface scanning (laser, structured light scanner, and photogrammetry) at two different quality settings (standard and high). 3D printed models of the lesions were produced using two different materials (a gypsum-like composite powder called VisiJet® PXL and an acrylic engineered composite plastic called VisiJet® M3 in crystal colour). The results of these analyzes indicate the prints in this study exhibit some statistically significant differences from the actual bone lesions, but details of the lesions can be reproduced to within 2 mm accuracy.

The influence of local bone quality on fracture pattern in proximal humerus fractures.

INTRODUCTION: Bone mineral density and fracture morphology are widely discussed and relevant factors when considering the different treatment options for proximal humerus fractures. It was the aim of this study to investigate the influence of local bone quality on fracture patterns of the Neer classification as well as on fracture impaction angle in these injuries. MATERIALS AND METHODS: All acute, isolated and non-pathological proximal humerus fractures admitted to our emergency department were included. The fractures were classified according to Neer and the humeral head impaction angle was measured. Local bone quality was assessed using the Deltoid Tuberosity Index (DTI). The distribution between DTI and fracture pattern was analysed. RESULTS: 191 proximal humerus fractures were included (61 men, mean age 59 years; 130 women, mean age 69.5). 77 fractures (40%) were classified as one-part, 72 (38%) were two-part, 24 (13%) were three- and four-part and 18 (9%) were fracture dislocations. 30 fractures (16%) were varus impacted, whereas 45 fractures (24%) were classified as valgus impacted. The mean DTI was 1.48. Valgus impaction significantly correlated with good bone quality (DTI ≥ 1.4; p = 0.047) whereas no such statistical significance was found for the Neer fracture types. DISCUSSION: We found that valgus impaction significantly depended on good bone quality. However, neither varus impaction nor any of the Neer fracture types correlated with bone quality. We conclude that the better bone quality of valgus impacted fractures may be a reason for their historically benign amenability to ORIF. On the other hand, good local bone quality does not prevent fracture comminution.

The effect of range and ammunition type on fracture patterns in porcine postcranial flat bones.

Pig half-carcasses were shot in scapulae, ribs and mandibles with either 0.243 hunting rifle using high velocity expanding ammunition (N = 30) or AK47 using full metal jacketed (FMJ) ammunition (N = 12) from a range of either 5 or 20 m. Fracture patterns related to distance of fire and ammunition type were compared on de-fleshed, macerated, and reconstructed bones. For expanding ammunition, location of fracture on ribs affected the resulting pattern. Scapulae shot from 5 m presented a comminuted pattern different from those shot from 20 m. Mandibles shot from 20 m showed a characteristic radiating pattern at entrance with the opposite ramus un-fractured; those shot from 5 m exhibited fractures to both rami. Using decision tree analysis provided accuracies of 93.8% for scapulae and 87.5% for mandibles. For FMJ, no distance dependent fracture differences were apparent in any bone. Decision tree analysis facilitated the interpretation of fracture patterns caused by projectile trauma.

Compound mechanism of fatal neck injury: A case report of a tiger attack in a zoo.

Fatal injuries caused by attacks by large wild cats are extremely rare in forensic medical practice in Europe. There are very few cases described in the forensic medical literature concerning incidents in zoos similar to the tiger attack on a 58-year-old male zoo employee that we present here. While preparing a runway for tigers, the man was attacked by a male Sumatran tiger. Another zoo employee was an eyewitness to the accident; in his testimony he described the sequence of events in detail. The autopsy showed the injuries typical of a tiger attack: traces of claws and canine teeth indicating that the victim of the attack was knocked down from behind, along with deep and extensive fatal wounds to the neck. The injuries were inflicted by means of a compound mechanism: tissues were penetrated by the animal's canines, crushed with great force (transfixing injury), and violently distended. The skin revealed four characteristic deep wounds caused by canines as well as bite marks resulting from the action of six incisors. The neck area revealed extensive damage, including torn muscles, the esophagus and trachea, large blood vessels of the neck, and fractures of vertebrae C2 and C5 with internal channels resulting directly from penetration by the animal's canines. The mechanism of distension, as a result of the animal jerking its head after biting the victim in the neck, produced a complete tear of the spine and the vertebral arteries, as well as an intramural rupture of the carotid arteries which has never been described before. In the interests of a detailed assessment of bone damage, the cervical spine was macerated. The applied autopsy techniques and detailed analysis of injuries enabled us to demonstrate the compound mechanism that inflicted them, combining penetration of tissues by the canines, crushing, and distension.

Fracture morphology of AO/OTA 31-A trochanteric fractures: A 3D CT study with an emphasis on coronal fragments.

AIMS: This study was designed to assess the incidence and morphology of coronal plane fragments in AO/OTA 31-A trochanteric fractures. PATIENTS AND METHODS: 156 cases of AO/OTA 31-A trochanteric fractures were retrospectively evaluated. Lateral radiographs were analyzed for the presence of coronal plane fragments followed by analysis of 3D CT reconstructions in these fractures. The incidence of coronal fragments identified on the lateral radiograph and 3D CT reconstructions were both calculated. Coronal fragment morphology was described based upon the origin and exit points of fracture lines and the number of fragments. RESULTS AND CONCLUSION: On plain radiographs, a coronal plane fracture was identified in 59 cases, an incidence of 37.8% (59/156). In comparison, 3D CT reconstructions identified coronal plane fractures in 138 cases for an incidence of 88.4% (138/156). 3D CT reconstructions identified coronal fracture fragments in 81.9% (50/61) of AO/OTA 31-A1 cases, 94.5% (69/73) of 31-A2 cases, and 86.3% (19/22) of 31-A3 cases. Incidence of coronal fractures identified on plain radiographs of 3 AO/OTA 31-A1,A2,A3 groups was lower when compared to the incidence of coronal fractures identified on 3D CT. Of the 138 cases that had coronal plane fracture, 82 cases (59.4%) had a single coronal fragment (GT fragment 35 cases, GLT fragment 19 cases, GLPC fragment 28 cases). The remaining 56 cases (40.5%) had two coronal fragments. There is a high incidence of coronal fragments in intertrochanteric femur fractures when analyzed with 3D CT reconstructions. Our study suggests that these coronal fragments are difficult to identify on plain radiographs. Knowledge of the incidence and morphology of coronal fragments helps to avoid potential intraoperative pitfalls.