Emergency treatment of pelvic ring injuries: state of the art.

High energy pelvic injuries sustain significant mortality rates, due to acute exsanguination and severe associated injuries. Managing the hemodynamically unstable trauma patient with a bleeding pelvic fracture still forms a major challenge in acute trauma care. Various approaches have been applied through the last decades. At present the concept of Damage Control Resuscitation (DCR) is universally accepted and applied in major trauma centers internationally. DCR combines hemostatic blood transfusions to restore blood volume and physiologic stability, reduced crystalloid fluid administration, permissive hypotension, and immediate hemorrhage control by operative or angiographic means. Different detailed algorithms and orders of hemostatic procedures exist, without clear consensus or guidelines, depending on local traditions and institutional setups. Fracture reduction and immediate stabilization with a binder constitute the basis for angiography and embolization (AE) or pelvic packing (PP) in the hemodynamically unstable patient. AE is time consuming and may not be available 24/7, whereas PP offers a quick and technically easy procedure well suited for the patient in extremis. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has also been described as a valuable adjunct in hemostatic non-responders, but merely constitute a bridge to surgical or angiographic hemostasis and its definitive role in DCR is not yet clearly established. A swift algorithmic approach to the hemodynamically unstable pelvic injury patient is required to achieve optimum results. The present paper summarizes the available literature on the acute management of the bleeding pelvic trauma patient, with emphasis on initial assessment and damage control resuscitation including surgical and angiographic hemostatic procedures. Furthermore, initial treatment of open fractures and associated injuries to the nervous and genitourinary system is outlined.

Course and Relation of the Facial Vessels-An Anatomical Study.

Background and Objectives: Facial vascular anatomy plays a pivotal role in both physiological context and in surgical intervention. While data exist on the individual course of the facial artery and vein, to date, the spatial relationship of the vasculature has been ill studied. The aim of this study was to assess the course of facial arteries, veins and branches one relative to another. Materials and Methods: In a total of 90 halved viscerocrania, the facial vessels were injected with colored latex. Dissection was carried out, the relation of the facial vessels was studied, and the distance at the lower margin of the mandible was measured. Furthermore, branches including the labial and angular vessels were assessed. Results: At the base of the mandible, the facial artery was located anterior to the facial vein in all cases at a mean distance of 6.2 mm (range 0-15 mm), with three cases of both vessels adjacent. An angular vein was present in all cases, while an angular artery was only present in 34.4% of cases. Conclusions: The main trunk of the facial artery and vein yields a rather independent course, with the facial artery always located anterior to the vein, while their branches, especially the labial vessels, demonstrate a closer relationship.

In vivo ligamentogenesis in embroidered poly(lactic-co-ε-caprolactone) / polylactic acid scaffolds functionalized by fluorination and hexamethylene diisocyanate cross-linked collagen foams.

Although autografts represent the gold standard for anterior cruciate ligament (ACL) reconstruction, tissue-engineered ACLs provide a prospect to minimize donor site morbidity and limited graft availability. This study characterizes the ligamentogenesis in embroidered poly(L-lactide-co-ε-caprolactone) (P(LA-CL)) / polylactic acid (PLA) constructs using a dynamic nude mice xenograft model. (P(LA-CL))/PLA scaffolds remained either untreated (co) or were functionalized by gas fluorination (F), collagen foam cross-linked with hexamethylene diisocyanate (HMDI) (coll), or F combined with the foam (F + coll). Cell-free constructs or those seeded for 1 week with lapine ACL ligamentocytes were implanted into nude mice for 12 weeks. Following explantation, cell vitality and content, histo(patho)logy of scaffolds (including organs: liver, kidney, spleen), sulphated glycosaminoglycan (sGAG) contents and biomechanical properties were assessed.Scaffolds did not affect mice weight development and organs, indicating no organ toxicity. Moreover, scaffolds maintained their size and shape and reflected a high cell viability prior to and following implantation. Coll or F + coll scaffolds seeded with cells yielded superior macroscopic properties compared to the controls. Mild signs of inflammation (foreign-body giant cells and hyperemia) were limited to scaffolds without collagen. Microscopical score values and sGAG content did not differ significantly. Although remaining stable after explantation, elastic modulus, maximum force, tensile strength and strain at Fmax were significantly lower in explanted scaffolds compared to those before implantation, with no significant differences between scaffold subtypes, except for a higher maximum force in F + coll compared with F samples (in vivo). Scaffold functionalization with fluorinated collagen foam provides a promising approach for ACL tissue engineering. a Lapine anterior cruciate ligament (LACL): red arrow, posterior cruciate ligament: yellow arrow. Medial anterior meniscotibial ligament: black arrow. b Explant culture to isolate LACL fibroblasts. c Scaffold variants: co: controls; F: functionalization by gas-phase fluorination; coll: collagen foam cross-linked with hexamethylene diisocyanate (HMDI). c1-2 Embroidery pattern of the scaffolds. d Scaffolds were seeded with LACL fibroblasts using a dynamical culturing approach as depicted. e Scaffolds were implanted subnuchally into nude mice, fixed at the nuchal ligament and sacrospinal muscle tendons. f Two weeks after implantation. g Summary of analyses performed. Scale bars 1 cm (b, d), 0.5 cm (c). (sketches drawn by G.S.-T. using Krita 4.1.7 [Krita foundation, The Netherlands]).

Microstructural analysis on the innervation of the anterior, medial, and lateral human hip capsule: Preliminary evidence on its neuromechanical contribution.

OBJECTIVE: Capsular repair aims to minimize damage to the hip joint capsular complex (HJCC) and subsequent dislocation risk following total hip arthroplasty (THA). Numerous explanations for its success have been advocated, including neuromuscular feedback loops originating from within the intact HJCC. This research investigates the hypothesis that the HJCC contributes to hip joint stability by analyzing HJCC innervation. METHOD: Twenty-nine samples from the anterior, medial, and lateral aspects of the midportion HJCC of 29 individuals were investigated stereologically and immunohistochemically to identify encapsulated mechanoreceptors according to a modified Freeman and Wyke classification, totaling 11,745 sections. Consecutive slices were observed to determine the nerve course within the HJCC. RESULTS: Few encapsulated mechanoreceptors were found in the HJCC subregions and overlying tissues across the cohort studied. Of regions studied, no significant regional differences in the density of mechanoreceptors were found. No significant difference in mechanoreceptor density was found between sides (left, 10.2×10-4/mm3, 4.0×10-4 - 19.0×10-4/mm3; right 12.9×10-4/mm3, 5.0×10-4 - 22.0×10-4/mm3; mean, 95% confidence intervals) sexes (female 10.4×10-4/mm3, 4.0×10-4 - 18.0×10-4/mm3; male 11.6×10-4/mm3, 5.0×10-4 - 20.0×10-4/mm3; mean, 95% confidence intervals), nor in correlation with age demographics. Myelinated nerves coursed consistently within the HJCC in various orientations. CONCLUSION: Sparse mechanoreceptor density suggests that the HJCC contributes to a limited extent to hip joint stabilization. HJCC nerve terminals may potentially contribute to neuromuscular feedback loops with associated muscles to mediate joint stability in tandem with the active and passive components of the joint.

Influence of size and shape of the auricular surfaces on subchondral bone density distribution in the sacroiliac joint.

The sacroiliac auricular surface has a variable morphology and size. The impact of such variations on subchondral mineralization distribution has not been investigated. Sixty-nine datasets were subjected to CT-osteoabsorptiometry for the qualitative visualization of chronic loading conditions of the subchondral bone plate using color-mapped densitograms based on Hounsfield Units in CT. Auricular surface morphologies were classified into three types based on posterior angle size: Type 1: >160°, Type 2: 130-160° and Type 3: <130°. Auricular surface size was categorized based on the mean value (15.4 cm2 ) separating the group into 'small' and 'large' joint surfaces. Subchondral bone density patterns were qualitatively classified into four color patterns: two marginal patterns (M1 and M2) and two non-marginal patterns (N1 and N2) and each iliac and sacral surface was subsequently categorized. 'Marginal' meant that 60-70% of the surface was less mineralized compared with the highly dense regions and vice versa for the 'non-marginal' patterns. M1 had anterior border mineralization and M2 had mineralization scattered around the borders. N1 had mineralization spread over the whole superior region, N2 had mineralization spread over the superior and anterior regions. Auricular surface area averaged 15.4 ± 3.6 cm2 , with a tendency for males to have larger joint surfaces. Type 2 was the most common (75%) and type 3 the least common morphology (9%). M1 was the most common pattern (62% of surfaces) by sex (males 60%, females 64%) with the anterior border as the densest region in all three morphologies. Sacra have a majority of surfaces with patterns from the marginal group (98%). Ilia have mineralization concentrated at the anterior border (patterns M1 and N2 combined: 83%). Load distribution differences related to auricular surface morphology seems to have little effect on long-term stress-related bone adaptation visualized with CT-osteoabsorptiometry. Higher iliac side mineralization was observed in larger joint surfaces and age-related morphomechanical size alterations were seen in males.

PaCO2 trajectories in mechanically ventilated patients with COVID-19: A population-based cohort study.

OBJECTIVE: To identify PaCO2 trajectories and assess their associations with mortality in critically ill patients with coronavirus disease 2019 (COVID-19) during the first and second waves of the pandemic in Denmark. DESIGN: A population-based cohort study with retrospective data collection. PATIENTS: All COVID-19 patients were treated in eight intensive care units (ICUs) in the Capital Region of Copenhagen, Denmark, between March 1, 2020 and March 31, 2021. MEASUREMENTS: Data from the electronic health records were extracted, and latent class analyses were computed based on up to the first 3 weeks of mechanical ventilation to depict trajectories of PaCO2 levels. Multivariable Cox regression analyses were used to calculate adjusted hazard ratios (aHRs) for Simplified Acute Physiology Score 3, sex and age with 95% confidence intervals (CIs) for death according to PaCO2 trajectories. MAIN RESULTS: In latent class trajectory models, including 25,318 PaCO2 measurements from 244 patients, three PaCO2 latent class trajectories were identified: a low isocapnic (Class I; n = 130), a high isocapnic (Class II; n = 80), as well as a progressively hypercapnic (Class III; n = 34) trajectory. Mortality was higher in Class II [aHR: 2.16 {1.26-3.68}] and Class III [aHR: 2.97 {1.63-5.40}]) compared to Class I (reference). CONCLUSION: Latent class analysis of arterial blood gases in mechanically ventilated COVID-19 patients identified distinct PaCO2 trajectories, which were independently associated with mortality.

Auricular surface morphology and surface area does not influence subchondral bone density distribution in the dysfunctional sacroiliac joint.

The subchondral lamella of the sacroiliac auricular surface is morphologically inconsistent. Its morpho-mechanical relationship with dysfunction (SIJD) remains unstudied. Here, the iliac and sacral subchondral bone mineralization is compared between morphological subtypes and in large and small surfaces, in SIJD joints and controls. CT datasets from 29 patients with bilateral or unilateral SIJD were subjected to CT-osteoabsorptiometry. Surface areas and posterior angles were calculated and surfaces were classified by size: small (<15 cm3 ) and large (≥15 cm3 ), and morphological types: 1 (>160°), 2 (130°-160°), and 3 (<130°). Mineralization patterns were identified: two marginal (M1 and M2) and two non-marginal (N1 and N2). Each sacral and iliac surface was subsequently classified. Dysfunctional cohort area averaged 15.0 ± 2.4 cm2 (males 16.2 ± 2.5 cm2 , females 13.7 ± 1.6 cm2 ). No age correlations with surface area were found nor mean Hounsfield Unit differences when comparing sizes, sexes or morphology-type. Controls and dysfunctional cohort comparison revealed differences in female sacra (p = 0.02) and small sacra (p = 0.03). There was low-conformity in marginal and non-marginal patterns, 26% for contralateral non-dysfunctional joints, and 46% for dysfunctional joints. The majority of painful joints was of type 2 morphology (59%), equally distributed between small (49%) and large joints (51%). Larger joints had the highest frequency of dysfunctional joints (72%). Auricular surface morphology seems to have little impact on pain-related subchondral lamella adaptation in SIJD. Larger joints may be predisposed to the onset of pain due to the weakening of the extracapsular structures. Dysfunctional joints reflect common conformity patterns of sacral-apex mineralization with corresponding superior corner iliac mineralization.

Two fingerbreadths, one finger's width: on the proximity of the radial nerve to the deltoid tuberosity.

INTRODUCTION: The aim of this study was to find a convenient technique to evaluate the location of the radial nerve (RN) with reference to the deltoid tuberosity (DT). MATERIALS AND METHODS: Sixty-eight upper extremities, embalmed using a modified version of Thiel's method, were included in the study. The interval between the tip of the greater tubercle of the humerus and the distal tip of the lateral humeral epicondyle (LE) was defined as humeral length (HL). The most prominent point of the DT was used as the point of reference. Through this point, a horizontal reference line which met the humeral axis at the dorsal side of the humeral shaft was simulated. The longitudinal distance between the crossing point of the horizontal line and the humeral axis and the RN was measured (distance 1). The interval between the intersection point and the reference point at the DT was measured (distance 2). Data were evaluated in centimeters. RESULTS: For the whole sample, the HL averaged 31.0 cm (SD: 2.3; range 26.2-36.9). Distance 1 averaged 2.2 cm (SD: 0.3; range 1.6-3.1), and distance 2 averaged 1.2 cm (SD: 1.0; range 0-2.8). The HL was larger in the male group when compared to females (p < 0.001; males mean: 32.2 cm; females mean 29.5 cm). There was no difference regarding distance 2 (p = 0.59; males mean: 1.2 cm; females mean: 1.3 cm) between the sexes. Distance 1 was significantly (p = 0.02) larger in the male group (mean: 2.3 cm) when compared to females (mean: 2.1 cm). Concerning sides, there were no differences regarding all evaluated parameters (HL: p = 0.6; Distance 1: p = 0.6; distance 2: p = 0.8). CONCLUSIONS: This study provides an easily applicable technique to localize the RN with reference to the DT.

The Course and Variation of the Facial Vein in the Face-Known and Unknown Facts: An Anatomical Study.

Background and Objectives: The facial vein is the main collector of venous blood from the face. It plays an important role in physiological as well as pathological context. However, to date, only limited data on the course and tributaries of the facial vein are present in contemporary literature. The aim of this study was to provide detail on the course and the tributaries of the facial vein. Materials and Methods: In 96 sides of 53 body donors, latex was injected into the facial vein. Dissection was carried out and the facial vein and its tributaries (angular vein, ophthalmic vein, nasal veins, labial veins, palpebral veins, buccal and masseteric veins) were assessed. Results: The facial vein presented a textbook-like course in all cases and crossed the margin of the mandible anterior to the masseter in 6.8% of cases, while being located deep to the zygomaticus major muscle in all cases and deep to the zygomaticus minor in 94.6% of cases. Conclusions: This work offers detailed information on the course of the facial vein in relation to neighboring structures, which shows a relatively consistent pattern, as well as on its tributaries, which show a high variability.

New Insights into the Communications of the Facial Vein with the Dural Venous Sinuses.

Background and Objectives: Anastomoses of the extracranial and intracranial venous system have been described in the literature. The presence of such anastomoses may facilitate a possible spread of infection into the dural venous sinuses. However, the frequency and relevance of such anastomoses is highly debated. The aim of this study was to quantify frequencies of anastomoses between the facial vein and the dural venous sinuses. Materials and Methods: In 32 sides of 16 specimens, latex was injected into the facial vein. Dissection was carried out to follow and described these anastomoses, yielding the presence of latex in the intracranial venous system. Results: In 97% of cases, a dispersal of latex into the cavernous sinus as well as anastomoses was observed. A further dispersal of latex into other dural venous sinuses was found at rates ranging between 34% (transverse sinus)-88% (superior petrosal sinus), respectively. Conclusions: The presence of anastomoses between the extracranial and intracranial venous system in a majority of cases needs to be considered when dealing with pathologies as well as procedures in the facial region.

["B problems" in non-traumatic resuscitation room management]. / "B-Probleme" des nichttraumatologischen Schockraummanagements.

In the primary survey of resuscitation room management in critically ill nontrauma patients, the ABCDE (airway, breathing, circulation, disability, exposure) approach is used for immediate recognition and treatment of life-threatening conditions. "B problems" are associated with respiratory failure and require immediate treatment. The pathogenesis is diverse, especially in the nontrauma resuscitation room. Clinical examination, emergency sonography and knowledge of oxygenation techniques and ventilation are important components of diagnosis and therapy. Standardized procedures and regular training in the emergency room are of fundamental importance.

Sacrospinous and sacrotuberous ligaments influence in pelvis kinematics.

The alteration in mechanical properties of posterior pelvis ligaments may cause a biased pelvis deformation which, in turn, may contribute to hip and spine instability and malfunction. Here, the effect of different mechanical properties of ligaments on lumbopelvic deformation is analyzed via the finite element method. First, the improved finite element model was validated using experimental data from previous studies and then used to calculate the sensitivity of lumbopelvic deformation to changes in ligament mechanical properties, load magnitude, and unilateral ligament resection. The deformation of the lumbopelvic complex relative to a given load was predominant in the medial plane. The effect of unilateral resection on deformation appeared to be counterintuitive, suggesting that ligaments have the ability to redistribute load and that they play an important role in the mechanics of the lumbopelvic complex.

Is There a Nerve-free Zone in Which a Subscapularis Split Can Safely be Performed? An Anatomical Study Using Embalmed Specimens.

BACKGROUND: The subscapularis muscle, which is part of the rotator cuff, is located anterior to the shoulder. In anterior approaches to the shoulder, its supplying nerves are at risk of iatrogenic injury, which may cause postoperative complications. It is unclear whether there is any nerve-free zone in which a subscapularis split can be performed without risking nerve damage. QUESTIONS/PURPOSES: In an anatomical study, we asked: (1) With the arm abducted 60° and externally rotated, what are the median and shortest distances between the entrance point of the subscapular nerves into subscapularis muscle and the myotendinous junction of this muscle? (2) What are those distances in other positions of the shoulder? (3) Did those measurements differ between specimen sexes or sides? METHODS: In 84 shoulders of 66 embalmed anatomic specimens, the distance from the myotendinous junction of the subscapularis muscle to the entrance points of the subscapular nerves into the subscapularis muscle was measured using an inelastic thread and a millimeter gauge with the arm abducted 60° and rotated externally. In 16 of 84 shoulders, which were selected randomly, after taking the measurements with the arm abducted 60° and rotated externally, arm positions were changed and further measurements were taken with the arm abducted 60° and rotated neutrally, abducted 60° and rotated internally, and abducted 90° and rotated externally. The positions of the entrance points were described with statistical parameters and compared between different sides, sexes, and joint positions. Measurements were verified using eight fresh-frozen shoulders, showing no difference in distances compared with embalmed specimens and confirming reproducibility of measurements. Absolute distances were used to minimize possible distortion when using correlations and for straightforwardness and clinical applicability. RESULTS: The median (range) distance was 43 mm (24 to 64) for the upper subscapular nerve and 38 mm (23 to 59) for the lower subscapular nerve with the arm rotated externally and abducted 60°. In the 16 subsamples, internal rotation decreased the distance to 34 mm (24 to 49) and 31 mm (15 to 43), respectively, and maximal external rotation and 90° of abduction increased it up to 49 mm (30 to 64) and 41 mm (27 to 56). Comparison of left and right sides yielded no difference. Comparison of sexes showed distances for the lower subscapular nerve of 36 mm (23 to 54) in females versus 39 mm (24 to 60) in males. CONCLUSION: In no specimen did the nerve come closer than 23 mm medial to the myotendinous junction with the arm rotated externally and abducted. Therefore, not exceeding a distance of 20 mm medial to the myotendinous junction with the arm rotated externally seems to provide sufficient protection from nerve injury during surgery. CLINICAL RELEVANCE: Based on the described zone of 20 mm medial to the myotendinous junction, the risk of nerve injury in a subscapularis split approach can be minimized.

Immediate and six-week effects of wearing a knee sleeve following anterior cruciate ligament reconstruction on knee kinematics and kinetics: a cross-over laboratory and randomised clinical trial.

BACKGROUND: Elastic knee sleeves are often worn following anterior cruciate ligament reconstruction (ACLR) but their effects on movement patterns are unclear. AIM: To determine the immediate and six-week effects of wearing a knee sleeve on biomechanics of the knee during a step-down hop task. METHODS: Using a cross-over design, we estimated sagittal plane knee kinematics and kinetics and stance duration during a step-down hop for 31 participants (age 26.0 [SD 6.6] years, 15 women) after ACLR (median 16 months post-surgery) with and without wearing a knee sleeve. In a subsequent randomised clinical trial, participants in the 'Sleeve Group' (n = 9) then wore the sleeve for 6 weeks at least 1 h daily, while a 'Control Group' (n = 9) did not wear the sleeve. We used statistical parametric mapping to compare (1) knee flexion/extension angle and external flexion/extension moment trajectories between three conditions at baseline (uninjured side, unsleeved injured side and sleeved injured side); (2) within-participant changes for knee flexion angles and external flexion/extension moment trajectories from baseline to follow-up between groups. We compared discrete flexion angles and moments, and stance duration between conditions and between groups. RESULTS: Without sleeves, knee flexion was lower for the injured than the uninjured sides during mid-stance phase. When wearing the sleeve on the injured side, knee flexion increased during the loading phase of the stance phase. Discrete initial and peak knee flexion angles increased by (mean difference, 95% CIs) 2.7° (1.3, 4.1) and 3.0° (1.2, 4.9), respectively, when wearing the knee sleeve. Knee external flexion moments for the unsleeved injured sides were lower than the uninjured sides for 80% of stance phase, with no change when sleeved. The groups differenced for within-group changes in knee flexion trajectories at follow-up. Knee flexion angles increased for the Control group only. Stance duration decreased by 22% for the Sleeve group from baseline to follow-up (-89 ms; -153, -24) but not for the Controls. CONCLUSIONS: Application of knee sleeves following ACLR is associated with improved knee flexion angles during hop landing training. Longer term (daily) knee sleeve application may help improve hop stance duration, potentially indicating improved hop performance. TRIAL REGISTRATION: The trial was prospectively registered with the Australia New Zealand Clinical Trials Registry No: ACTRN12618001083280, 28/06/2018. ANZCTR.

Thirty years of Thiel embalming-A systematic review on its utility in medical research.

In 1992, Walter Thiel described and embalming method that rendered "lifelike" tissues. Over the last 30 years, the Thiel method has been introduced worldwide for medical training and scientific purposes. This review examines research which can be linked to the use of Thiel embalming. A systematic review was performed to identify articles published in the following categories: research content, disciplines involved, sources and quantities of tissues deployed, and changes in research scope related to changes in the chemical composition of Thiel embalming. Four-hundred twenty-four publications were included. A number of adaptations to the original Thiel protocol were found, aiming to provide suitable tissue-substitutes in the development of emerging medical technologies or procedures. Musculoskeletal surgery, anesthesia and intensive care were the most common disciplines that used Thiel embalmed tissues for research. Anatomy and biomechanics played a lesser role. An increase over time was observed in research outputs related to the Thiel method, while the number of specimens used per study decreased. The main centers using Thiel embalming were in Graz, Dundee, Sapporo, Bern, Zurich and Ghent, which jointly accounted for more than 54% of all research conducted using this method. Following three decades of use, the Thiel method has evolved into being a well-established embalming technique for research purposes. Its future is challenged by the demanding requirements on both technical facilities and personnel, limitations of certain chemicals for use as fixatives, costs, and questions as to how "lifelike" the embalmed-tissues are from an objective standpoint, all of which warrants future investigations.

Fat Is Consistently Present within the Plantar Muscular Space of the Human Foot-An Anatomical Study.

Background and Objectives: The foot comprises of active contractile and passive connective tissue components, which help maintain stability and facilitate movement during gait. The role of age- or pathology-related degeneration and the presence of fat within muscles in foot function and pain remains unclear. The existence of fat has to date not been quantified or compared between individuals according to age, sex, side or subregion. Materials and Methods: 18 cadaveric feet (mean age 79 years) were sectioned sagittally and photographed bilaterally. Fat in the plantar muscular space of the foot (PMSF) was quantified through the previously validated manual fat quantification method, which involved observing photographs of each section and identifying regions using OsiriX. Fat volume and percentage was calculated using a modified Cavalieri's method. Results: All feet had fat located within the PMSF, averaging 25.8% (range, 16.5-39.4%) of the total PMSF volume. The presence of fat was further confirmed with plastination and confocal microscopy. Conclusions: These findings suggest that fat within the PMSF is a consistent but highly variable finding in elderly cohorts. Fat within the foot muscles may need to be considered a norm when comparing healthy and non-healthy subjects, and for therapeutic interventions to the foot. Further work is required to understand in detail the morphological and mechanical presence of fat in the foot, and compare these findings with pathological cohorts, such as sarcopenia. Additionally, future work should investigate if fat may compensate for the degeneration of the intrinsic muscles of the foot, with implications for both the use of orthotics and pain management.

Ballistic trauma caused by military rifles: experimental study based on synthetic skull proxies.

Rifles are often involved in violent deaths such as homicide and suicide. Consequently, expert knowledge and experimental forensic investigations are important to clarify the nature of ballistic trauma when applied to the human head and neurocranium. This study investigated differences in entrance wound morphology with Synbone® spheres which are described as being comparable to human flat bones. A series of ballistic experiments were conducted using two different rifle calibers (5.56 × 45 mm and 7.62 × 39 mm Full Metal Jacket (FMJ)). Synbone® spheres were used for close-range 0.3 m simulated executions as well as at 25 m and 35 m to simulate urban and military engagements. Results were compared with previously published experimental studies using similar military ammunition. In our study, entry wound morphology closely resembles real forensic cases compared to exit wound and overall shape morphology independently of the distance and the caliber. Circumferential delamination was clearly visible with full metal jacket (FMJ) rounds, yielding similar damage pattern morphology to the human crania. This study documented the presence of hydraulic burst or shock in all ten rounds from all three distances. Krönlein shots were also observed in some cases. Synbone® spheres constitute an acceptable synthetic surrogate for ballistic experiments. The present study offers new initial data on the behavior of Synbone® proxies in ballistic testing of military ammunitions; FMJ gunshot injuries to the human head, for distances that have not previously been published, suggesting that efficient tests can take place under these conditions. Further research on experimental ballistics with a larger number of controlled factors and multiple repetitions is recommended to verify the results of this pilot study before applied in forensic simulations.

Preliminary observations of the sequence of damage in excised human juvenile cranial bone at speeds equivalent to falls from 1.6 m.

There is much debate within the forensic community around the indications that suggest a head injury sustained by a child resulted from abusive head trauma, rather than from accidental causes, especially when a fall from low height is the explanation given by a caregiver. To better understand this problem, finite element models of the paediatric head have been and continue to be developed. These models require material models that fit the behaviour of paediatric head tissues under dynamic loading conditions. Currently, the highest loading rate for which skull data exists is 2.81 ms-1. This study improves on this by providing preliminary experimental data for a loading rate of 5.65 ± 0.14 ms-1, equivalent to a fall of 1.6 m. Eleven specimens of paediatric cranial bone (frontal, occipital, parietal and temporal) from seven donors (age range 3 weeks to 18 years) were tested in three-point bending with an impactor of radius 2 mm. It was found that prompt brittle fracture with virtually no bending occurs in all specimens but those aged 3 weeks old, where bending preceded brittle fracture. The maximum impact force increased with age (or thickness) and was higher in occipital bone. Energy absorbed to failure followed a similar trend, with values 0.11 and 0.35 mJ/mm3 for age 3 weeks, agreeing with previously published static tests, increasing with age up to 9 mJ/mm3 for 18-year-old occipital bone. The preliminary data provided here can help analysts improve paediatric head finite element models that can be used to provide better predictions of the nature of head injuries from both a biomechanical and forensic point of view.

GFAP positivity in neurons following traumatic brain injuries.

Glial fibrillary acidic protein (GFAP) is a well-established astrocytic biomarker for the diagnosis, monitoring and outcome prediction of traumatic brain injury (TBI). Few studies stated an accumulation of neuronal GFAP that was observed in various brain pathologies, including traumatic brain injuries. As the neuronal immunopositivity for GFAP in Alzheimer patients was shown to cross-react with non-GFAP epitopes, the neuronal immunopositivity for GFAP in TBI patients should be challenged. In this study, cerebral and cerebellar tissues of 52 TBI fatalities and 17 controls were screened for immunopositivity for GFAP in neurons by means of immunohistochemistry and immunofluorescence. The results revealed that neuronal immunopositivity for GFAP is most likely a staining artefact as negative controls also revealed neuronal GFAP staining. However, the phenomenon was twice as frequent for TBI fatalities compared to non-TBI control cases (12 vs. 6%). Neuronal GFAP staining was observed in the pericontusional zone and the ipsilateral hippocampus, but was absent in the contralateral cortex of TBI cases. Immunopositivity for GFAP was significantly correlated with the survival time (r = 0.306, P = 0.015), but no correlations were found with age at death, sex nor the post-mortem interval in TBI fatalities. This study provides evidence that the TBI-associated neuronal immunopositivity for GFAP is indeed a staining artefact. However, an absence post-traumatic neuronal GFAP cannot readily be assumed. Regardless of the particular mechanism, this study revealed that the artefact/potential neuronal immunopositivity for GFAP is a global, rather than a regional brain phenomenon and might be useful for minimum TBI survival time determinations, if certain exclusion criteria are strictly respected.

Ultrasound in legal medicine-a missed opportunity or simply too late? A narrative review of ultrasonic applications in forensic contexts.

OBJECTIVES: Conventional autopsies remain the gold standard of postmortem healthcare quality assurance and help gathering extended knowledge on diseases. In answer to constantly declining autopsy rates non- or minimally invasive autopsy methods were introduced. Ultrasound is a well-established tool for imaging commonly used in clinical practice. This narrative review aims to summarize the current literature regarding the feasibility and validity of ultrasound in a forensic context. MATERIAL AND METHODS: A PubMed database search was carried out. Abstracts were scanned for pre-defined ex- and inclusion criteria, followed by a snowball search procedure applied to the primarily included articles. RESULTS: Forty-five publications met our inclusion criteria. The selected articles concern the feasibility of ultrasound in pre- or postmortem settings, forensic age estimation, and minimally invasive approaches. For imaging, ultrasound was deemed a reliable tool for the examination of epiphyses und superficial wounds, with limitations regarding internal organs and image quality due to postmortem changes. Ultrasound-guided minimally invasive approaches yielded higher success rates for adequate tissue sampling. Many investigations were carried out in low- and middle-income countries focusing on infectious diseases. CONCLUSION: Ultrasound seems a promising but underutilized imaging tool in legal medicine to date. Promising approaches on its feasibility have been conducted. Especially for minimally invasive methods, ultrasound offered significant improvements on qualified biopsy sampling and thus appropriate diagnostics. Moreover, ultrasonic evaluation of epiphyses for age estimation offered valuable results. Nevertheless, further assessment of ultrasonic feasibility in forensic contexts is needed.