Human Cadaver Research Articles

Possibility of growing insect eggs on human cadavers preserved at sub‐zero temperatures for different time intervals

AbstractInsects are the first arthropods to invade cadavers and, thus, can be used as evidence in criminal investigations. The current study aimed to investigate the possibility of breeding insect eggs in the lab that would be collected from male human cadavers kept in the mortuary refrigerators at sub‐freezing temperatures for different periods. Egg specimens were collected from different human cadavers preserved from −16 to −20°C for different time intervals. All collected eggs were incubated at 25–30°C and 60%–70% and observed until hatched larvae complete their life cycle. All obtained larvae and adults were identified based on morphological characteristics. Data showed that, at selected ranges of temperature and humidity, some eggs were hatched to the first larval stage and then stopped growing, while others completed their life cycle to the adult insect stage. The obtained adult insects were identified using morphological classification and found to belong to Dermestes frischii.

Posteromedial Periarticular Injection in Total Knee Arthroplasty: A Cadaveric Study.

Achieving optimal pain control in total knee arthroplasty has improved with the use of regional anesthesia and periarticular injections (PAIs). When performing a PAI, the relative location of the anesthetic spread is not well defined in comparison with an adductor canal block (ACB). In this study, our aim was to evaluate the location of posteromedial PAI spread compared with a surgeon administered ACB. One PAI and one surgeon-administered ACB were performed in the contralateral limbs of four human cadavers. The injectate was composed of methylene blue dye to visually inspect the dye spread from the tip of the needle. Dissections were performed on each cadaver to quantify the dye spread from the tip of the needle and compare the location of the dye spread. Dye spread location was characterized as either entering the adductor canal or including the posterior capsule. The mean distance of dye spread from the needle tip to the proximal most aspect of the dyed tissue was 10.125 cm in the ACB group compared with 6.5 cm in the posteromedial PAI group. In the ACB group, 4 of 4 injections were present in the adductor canal block group compared with 3 of 4 in the posteromedial PAI group. The posteromedial PAI group also had 3 of 4 injections involve the area around the posterior capsule compared with 0 of 4 in the ACB group. Posteromedial PAI appears to provide local delivery to both the adductor canal and the posterior capsule. Intraoperative, surgeon-administered ACB reliably delivers injectate to the adductor canal only but may allow for more proximal dye spread. Posteromedial PAI may provide a benefit in delivering injectate to the posterior capsule in addition to the ACB. Additional clinical studies are necessary to determine the clinical effects of this finding.

Conditioned Canine Cadavers for Near-Natural Interprofessional Veterinary and Human Surgery Training.

Both medical and veterinary students find that the use of cadavers is critical to learning anatomical structures and surgical techniques. The use of human cadavers and the resulting user emotions are driven by serious ethical issues that are currently much less pronounced in veterinary education. Ethically sourced canine cadavers, thus, are more readily available. Aesthetics such as odor and visual appearance, though, influence both learner and educator motivation.We have investigated a way of delaying cadaver decomposition by post-mortem in situ, chemical-free, gastrointestinal lavage.We are convinced that canine cadavers, conditioned as described here, will improve the outcome of cadaver-based surgical skills training by facilitating preparation, reducing the number of required cadavers, postponing decomposition, improving the surgeon's haptic-tactile response to organ and tissue handling and suturing, and, possibly most importantly, increasing learners' and educators' focus due to the significantly improved aesthetics. We hypothesize that skill transfer for medical students and doctors, because of the similar abdominal anatomy, may be easier when training with conditioned canine cadavers as compared to artificial simulators or pigs in vivo.

Evaluation of a compounding phospholipid base for the percutaneous absorption of high molecular weight drugs using the Franz finite dose model.

Permeation-enhancing compounding bases are aimed to facilitate the penetration of the active pharmaceutical ingredients (APIs) across the skin barrier. The purpose of this study was to evaluate the percutaneous absorption of radiolabeled human insulin (14 C-isototpe) when incorporated in a proprietary phospholipid base designed to deliver APIs with high molecular weights (HMW). The aim was not to claim the transdermal delivery of insulin with potential therapeutic applications in diabetes but, instead, to evaluate the ability of the compounding phospholipid base to deliver HMW drugs. The percutaneous absorption of 14 C-insulin was determined using human torso skin and the Franz skin finite dose model. Two topical test formulations were prepared for in vitro evaluation: insulin 1% in phospholipid base (standard) and insulin 1% in phospholipid base HMW. The rate of percutaneous absorption (mean flux) and the distribution of 14 C-insulin through the skin were evaluated for both topical test formulations. A two-way ANOVA was used to determine statistical differences. The 14 C-insulin was distributed into the stratum corneum, epidermis and dermis. Mean flux values showed a rapid penetration upon application and the maximum flux was achieved at 30 min, followed by a slow decline. Subsequently, a slower decline was observed for the topical test formulation including the phospholipid base HMW. The phospholipid base HMW facilitates the percutaneous absorption of HMW drugs across human cadaver skin and, therefore, it may potentially be a useful option for compounding pharmacists and practitioners when considering the skin for the percutaneous delivery of large drugs.

Review of ultrasound-guided labeling: exploring its potential in teaching cadaveric ligaments during anatomical dissection courses.

This scoping review aimed to give an overview of the existing literature about ultrasound-guided labeling techniques of human cadaver ligaments and tried to work out the possibilities of integrating ultrasound into dissection courses. A literature review was carried out on the 3rd of January 2023, with relevant studies discovered in the following databases: MEDLINE, EMBASE, CENTRAL, BIOSIS Previews and Web of Science Core Collection. Grey literature was also considered. The reference lists of all relevant papers were scanned. Only ultrasound studies on human cadaver ligaments were included. The included studies' general characteristics and ultrasound-guided approaches to label the ligaments were taken from them and examined. The search found 8899 matches, but only 96 of them met the criteria. The transverse carpal ligament (15.62%) and the annular pulleys (19.79%) were the ligaments that had received the greatest research attention. Twenty-three studies are included in the methodological analysis. Both the marking substrate and the injected volume were diverse. Although 65% of the included studies achieved 100% accuracy using the ultrasound directed labeling approaches. Ultrasound-guided labeling techniques achieve a high accuracy. Therefore, this methodology could be a potential teaching tool for students during the dissection course. But caution is advised in drawing general conclusions because of the small sample sizes and different methodologies in the studies. Future larger-scale research is necessary.

3D-assisted corrective osteotomies of the distal radius: a comparison of pre-contoured conventional implants versus patient-specific implants

PurposeThere is a debate whether corrective osteotomies of the distal radius should be performed using a 3D work-up with pre-contoured conventional implants (i.e., of-the-shelf) or patient-specific implants (i.e., custom-made). This study aims to assess the postoperative accuracy of 3D-assisted correction osteotomy of the distal radius using either implant.MethodsTwenty corrective osteotomies of the distal radius were planned using 3D technologies and performed on Thiel embalmed human cadavers. Our workflow consisted of virtual surgical planning and 3D printed guides for osteotomy and repositioning. Subsequently, left radii were fixated with patient-specific implants, and right radii were fixated with pre-contoured conventional implants. The accuracy of the corrections was assessed through measurement of rotation, dorsal and radial angulation and translations with postoperative CT scans in comparison to their preoperative virtual plan.ResultsTwenty corrective osteotomies were executed according to their plan. The median differences between the preoperative plan and postoperative results were 2.6° (IQR: 1.6–3.9°) for rotation, 1.4° (IQR: 0.6–2.9°) for dorsal angulation, 4.7° (IQR: 2.9–5.7°) for radial angulation, and 2.4 mm (IQR: 1.3–2.9 mm) for translation of the distal radius, thus sufficient for application in clinical practice. There was no significant difference in accuracy of correction when comparing pre-contoured conventional implants with patient-specific implants.Conclusion3D-assisted corrective osteotomy of the distal radius with either pre-contoured conventional implants or patient-specific implants results in accurate corrections. The choice of implant type should not solely depend on accuracy of the correction, but also be based on other considerations like the availability of resources and the preoperative assessment of implant fitting.

IDEAL-D Phase 0 Evaluation of the Avatera System in Robot-Assisted Prostate, Bladder and Renal Surgery.

Purpose: To evaluate the utilization of novel Avatera system in urological operations according to the IDEAL-D framework recommendations for high-risk invasive surgical devices. Materials and Methods: Three surgeons attempted to perform 23 upper and lower urinary tract operations on human cadavers and in live porcine models using the Avatera system. Total operative time and the duration of the substeps were evaluated. Surgical performance was assessed with the Global Evaluative Assessment of Robotic Skills (GEARS) score. Suturing was rated using the technical checklist for the assessment of suturing in robotic surgery. Attending surgeons rated their satisfaction with the Avatera system on a scale of 1-5. Results and Limitation: Seventeen out of 18 operations performed on cadavers were completed, while one pyeloplasty was discontinued. All five operations performed in porcine models were completed. Although 1 pig was euthanized on the fifth postoperative day, its symptoms were unrelated to surgery. Mean GEARS and Suturing scores in the upper urinary tract were 29 ± 0.7 and 29.5 ± 0.95, respectively, and in the lower urinary 28.5 ± 1.2 and 29.5 ± 0.5, respectively. Surgeons' satisfaction was high or very high for all procedures. Conclusions: The Avatera system was associated with good surgical performance and high surgeons' satisfaction rates. All urological procedures performed were shown to be feasible, with comparable risks to other robot-assisted surgery systems.

Artificial Octopus-Limb-Like Adhesive Patches for Cupping-Driven Transdermal Delivery with Nanoscale Control of Stratum Corneum.

Drug delivery through complex skin is currently being studied using various innovative structural and material strategies due to the low delivery efficiency of the multilayered stratum corneum as a barrier function. Existing microneedle-based or electrical stimulation methods have made considerable advances, but they still have technical limitations to reduce skin discomfort and increase user convenience. This work introduces the design, operation mechanism, and performance of noninvasive transdermal patch with dual-layered suction chamber cluster (d-SCC) mimicking octopus-limb capable of wet adhesion with enhanced adhesion hysteresis and physical stimulation. The d-SCC facilitates cupping-driven drug delivery through the skin with only finger pressure. Our device enables nanoscale deformation control of stratum corneum of the engaged skin, allowing for efficient transport of diverse drugs through the stratum corneum without causing skin discomfort. Compared without the cupping effect of d-SCC, applying negative pressure to the porcine, human cadaver, and artificial skin for 30 min significantly improved the penetration depth of liquid-formulated subnanoscale medicines up to 44, 56, and 139%. After removing the cups, an additional acceleration in delivery to the skin was observed. The feasibility of d-SCC was demonstrated in an atopic dermatitis-induced model with thickened stratum corneum, contributing to the normalization of immune response.

A reliable, battery-free and implantable magnetic sensing system for wireless monitoring of spinal motion in rats and humans

Continuous monitoring of spinal and joint motions in patients allows surgeons to optimize patient rehabilitation. However, the current monitoring approaches are achieved via tethered devices, which are inconvenient and associated with a risk of infections. In this study, we developed and validated a new type of reliable wireless, battery-free, and implantable sensing system (RWBS) for the real-time monitoring of physiological bending of spines and joints. The RWBS exploits the unique movement-sensing capabilities of an implantable flexible magnetic strip, the signals from which are detected with an external receiver. We implanted this magnetic strip beneath the skins of Sprague Dawley rats and human cadavers and demonstrated that in combination with the receiver, the magnetic strip enabled real-time in vivo and wireless monitoring of motions in both rats (anesthetized/awake) and human cadavers. The adaptability of RWBS in other human bones has been verified by sensing the motions of elbow joints and knee joints. The simple design of the RWBS allowed it to continue functioning in vivo after the magnetic strip had been broken into two or more pieces, indicating its high reliability. Thus, the RWBS is biocompatible, exhibits excellent functionalities, and can be conveniently implemented in both rats and humans. This device will help to facilitate the post-surgery monitoring of spinal and joint movements of human patients.

Maxillary Sinus Measurements in Different Age Groups of Human Cadavers

The maxillary air sinus is the largest air sinus among the four air paranasal sinuses, which is a cavity in the body of maxilla. It is pyramidal in shape co nsisting of base, apex and four sides; its base comprises the thin lateral wall of nasal cavity. This study carried out at the Institute of Forensic Medicine in Baghdad and the Forensic Medicine Unit in Tikrit Teaching Hospital during the period from January 2010 to July 2011. A randomized sample of 110 human cadavers that arranged in four different age groups and dissected to study the three dimensions of both maxillary sinuses in both sexes by using a standard flexible tape measure or vernier caliper. The mean v alue of the maxillary sinus length in males was (36.4 ± 4.6 mm) and in females was (33.9 ± 4.2 mm); from these results, the mean value of males was significantly greater than that of females. On the other side, the mean value of the maxillary sinus width in males was (27.4 ± 4 mm) and in females was (25.3 ± 3.9 mm); therefore, these results demonstrate that the maxillary sinuses were wider in males than females. For males, the mean value of the maxillary sinus height was (35.1 ± 3.9 mm) and for females was (30.8 ± 3.6 mm). From these findings, a higher significant difference between the mean values was found; also there was a high significant difference between the two genders because the mean value of the maxillary sinus height for males was significantly higher than that for females. According to age groups of the present study, group 1 of maxillary sinus found to be still in growing state and not reaching its full size. Group 2 showing an extensive growth in maxillary sinus length and width, especially on the right side. Group 3 might partly showing growth in maxillary sinus length and height, which indicates that at this age the maxillary sinus reaches its full height. Finally, group 4 might partly indicates that the maxillary sinus reaches its full growth if it fails to reach it in group 3. The findings of the present study disagree with that done by Parks who mademeasurements for the maxillary sinuses on normal Korean adults using computed tomography, since these differences were may be due to ethnic variations. Also due to race differences, this study disagree with Fernandes (2) who studied the maxillary sinus in European and Zulu using computed tomography.

Acquisition of cadavers for anatomy education and research in Malawi

BackgroundThe use of human cadaveric dissection forms an essential part of teaching anatomy to health sciences students in Malawi. Despite worldwide struggles in acquiring sufficient human cadavers for anatomy education, the current recommendations on the best anatomy practices require the use of cadavers exclusively from the body donation programs. The current study aims to describe the sources of cadaveric bodies used for anatomy education in the Malawian context and reflect on the feasibility of using cadavers from the body donation program only. MethodsA retrospective audit of the cadaveric records for the 2006–2022 academic years at the Kamuzu University of Health Sciences was done. The perceived challenges when sourcing the cadavers were identified and described based on the authors experiences in Malawi. ResultsThe majority (97.3%) of the cadavers used between 2006 and 2022 were unclaimed bodies. The mean age of the cadavers was 45 years. Most (95.6%) of the unclaimed bodies were males. All the unclaimed bodies were sourced from hospitals. The body donation program in Malawi was patronized by populations of European descent only. Strongly held sociocultural and religious beliefs as well as economic reasons were perceived as significant barriers to acquiring cadavers of the indigenous Malawians through the body donation program. ConclusionCadavers for anatomy education in Malawi are mainly from unclaimed bodies, similar to other African countries. The authors support the transition from using “mostly unclaimed bodies (and, less often, body donation)” to using “mostly body donation (and, less often, unclaimed bodies)” through awareness campaigns that are targeted to address the prevailing challenges.

Use of Humour in Learning Anatomy in a Better Way in Lecture Theatre or Dissection Hall - A Questionnaire Based Study

Background: First year medical students normally experience a variety of emotional reactions and mixed feelings, when they encounter human cadavers for the first time. With changing curriculum, peer pressure, stressful work conditions, etc. it becomes tough or even difficult to relax our mind. Humour has been shown to boost motivation, improve problem-solving skills, and foster creativity and critical thinking. It also promotes a happy learning atmosphere and reduces examination anxiety. The purpose of this study was to assess opinions of medical students about using humour while learning Anatomy in acquiring excellence in clinical skills and knowledge. Material & Methods: 258 medical students participated in the study and responded to the paper-based questionnaire. The student questionnaire comprised of sixteen questions related to attitudes towards the use of humour in the subject of anatomy in lecture and dissection hall. The responses were collected and the data was then compiled and analysed. Results: 83.72% to 93.79% of students believed in the usefulness of humour in anatomy theory lectures in terms of increasing interest in learning Anatomy, making them less anxious in recalling the muscle attachment, concentrate better on the topic. All the students were of opinion that the use of humor created a comfortable classroom atmosphere that makes the learning experience more positive and helpful in improving rapport between student and teacher. A very low evaluation was observed that use of humour during teaching distracts attention of the students and wastage of time. Inappropriate humour related to sarcasm, mockery received 226(87.59%) evaluation. Students 203(78.68%) also emphasized the use of dark humour to cope with morbidity and stress during dissection. Ad-libbed humour was considered to be the most effective form of humour. Most students emphasized that humour worked best in a small amount i.e. 2-3 times of humorous remarks. Conclusion: Keeping in mind the effectiveness of the system of anatomy instruction it seems logical that the subject should be learned with humor. The present study confirms that most medical students support the use of humour in teaching anatomy topics.

Examining thermally induced movement of the fatal fire victim

Investigating a fatal fire scene comprises analysis not only of the fire’s development to identify the point of fire origin and ignition source, but analysis of a victim’s position and their relationship within the scene. This work presents both qualitative and quantitative results from experimentation investigating the effect of a real fire environment on the human body, and how the position of a victim at the post burn investigation stage may be significantly different to the position at fire ignition. Qualitative observations were undertaken on the burning of 39 compartment and vehicle scenes from ignition through to suppression, each containing a human cadaver. The results of analysis question the validity of previous work based on cremation observations. Quantitative results were produced by recording 13 points on the body on the X, Y and Z axis, both pre and post burn on a smaller dataset of ten compartment burns. Results have enabled a more robust assessment of thermally induced movement of the body within the scene along each axis, evidencing that pugilism is not the universal reaction of the fatal victim to thermal exposure, with extension of the upper limbs far more common than has been previously reported.

A study of splenic notches in human cadavers and its clinical implications

: Spleen is the largest and secondary lymphoid organ with high vascularity which has important role in immunological and haematological functions of human body. Spleen developes from mesoderm and in the initial stages of development, different lobules are formed, which fuses later. The lobulated structure of spleen disappears, but is indicated by the presence of notches in superior border in adults. The aim of study was to find morphological variations of spleen with respect to its number of notches in borders and anomalous fissure on its surfaces.: The study was done on 40 formalin fixed cadaveric spleens from the department of Anatomy, Sri Siddhartha Medical College, Tumkur, and Karnataka. Out of 40 spleens studied, the various shapes such as wedge shaped, tetrahedral, oval and triangular were found. The number of spleen showing notches in superior border was 28(70%) and in the inferior border it was 3(7.5%). Absence of Splenic notches was observed in 5(12.5%) and 2(5%) spleens had notches in both borders. The anomalous fissure was found in 2(5%) spleen on its diaphragmatic surface.: The knowledge of variations in morphology of spleen are essential for physician, surgeon, radiologists and forensic surgeon to differentiate from the splenic pathology and splenic injury. Morphological variations of spleen and its clinical importance need to be discussed at dissection tables during routine anatomy dissection hours.

Colorimetric variations in cadaveric tissues embalmed with modified Thiel\\\'s and Formalin solutions: An objective comparative study using image J

The comparison of tissue colour between Thiel's embalmed cadavers (TEC) and formalin-embalmed cadavers (FEC) is crucial for assessing the efficacy of Thiel embalming technique as a suitable alternative to formalin embalming for surgical skill training and anatomical education. Most of the studies which declare the superiority of tissue colour in TEC over FEC have done subjective assessment and comparison of the tissue colour. This study aims to compare the colour difference between Thiel and formalin embalmed cadavers objectively. : The current study used six human cadavers to compare the effects of two embalming methods, Modified Thiel’s solution (MTS) and Modified Formalin Solution(MFS). The tissues of the cadavers were dissected and photographed to be analysed for Red, Blue, Green values using Image J software. The mean (SD) R-value (Red), G-value (Green), and B-value (Blue) for MTS embalmed cadavers were 149.78 (16.070), 124 (19.675), and 109.96 (9.852), respectively, from pictures of embalmed cadavers from research groups. The mean RGB value of MTS embalmed cadavers was substantially (P<0.05) higher than MFS embalmed cadavers. The current research found that MTS-embalmed cadavers have greater RGB values than MFS-embalmed ones. This information helps to fully understand tissue property changes, evaluate their impact on student perceptions and learning outcomes, and determine Thiel embalming's suitability for surgical training and workshops.

Cadaveric study of ergonomics and performance using a robotic exoscope with a head-mounted display in spine surgery.

The conventional microscope has the disadvantage of a potentially unergonomic posture for the surgeon, which can affect performance. Monitor-based exoscopes could provide a more ergonomic posture, as already shown in pre-clinical studies. The aim of this study was to test the usability and comfort of a novel head-mounted display (HMD)-based exoscope on spinal surgical approaches in a simulated OR setting. A total of 21 neurosurgeons naïve to the device were participated in this prospective trial. After a standardized training session with the device, participants were asked to perform a single-level thoracolumbar decompression surgery on human cadavers using the exoscope. Subsequently, all participants completed a comfort and safety questionnaire. For the objective evaluation of the performance, all interventions were videotaped and analyzed. Twelve men and nine women with a mean age of 34 (range: 24-57) were participating in the study. Average time for decompression was 15min (IqR 9.6; 24.2); three participants (14%) terminated the procedure prematurely. In these dropouts, a significantly higher incidence of back/neck pain (p = 0.002 for back, p = 0.046 for neck pain) as well as an increased frequency of HMD readjustments (p = 0.045) and decreased depth perception (p = 0.03) were documented. Overall, the surgeons' satisfaction with the exoscope was 84% (IqR 75; 100). Using a standardized, pre-interventional training, it is possible for exoscope-naïve surgeons to perform sufficient spinal decompression using the HMD-based exoscope with a high satisfaction. However, inaccurate HMD setup prior to the start of the procedure may lead to discomfort and unsatisfactory results.

Four different models for simulation-based training of bronchoscopic procedures

BackgroundFlexible bronchoscopy procedures require detailed anatomical knowledge and advanced technical skills. Simulation-based training offers a patient-safe training environment that can be more efficient than patient-based training. Physical models are cheaper than virtual reality simulators and allow trainees to be acquainted with the equipment used in the clinic. The choice of a physical model for training depends on the local context. The aim of this study was to compare four different bronchoscopy models for flexible bronchoscopy training.MethodsThe BronchoBoy manikin, the Koken manikin, a human cadaver, and a preserved porcine lung were included in the study. Seven physicians experienced in bronchoscopy performed a bronchoscopic airway inspection, bronchoalveolar lavage (BAL), and tissue sampling on all four models with performance evaluated by observation and participant evaluation of models by questionnaire.ResultsNineteen segments were identified in all human anatomy models, and the only significant difference found was that only the Thiel embedded cadaver allowed all participants to enter RB1 with an instrument in the working channel (p = 0.001). The Thiel embedded cadaver and the BronchoBoy manikin had low fluid return on BAL (22 and 52 ml), whereas the Koken manikin and the preserved porcine lung had high return (132 and 134 ml), (p = 0.017). Tissue samplings were only completed in the preserved porcine lung and the Thiel embedded cadaver (p < 0.001).ConclusionsAn anatomically correct bronchoscopy is best simulated with the Koken manikin or the Thiel embedded cadaver. Bronchoalveolar lavage should be simulated with the Koken manikin or the preserved porcine lung. Tissue sampling procedures are best simulated using the Thiel embedded cadaver or the preserved porcine lung.

Dimorphic comparative histological and histometric study of the lateral and medial knee menisci in male and female human cadavers

The knee menisci are fibrocartilaginous discs present in between the femur and the tibia. They play a pivotal role in withstanding the weight-bearing forces and help to maintain the stability of the knee joint. Descriptive knowledge of the menisci is essential to understand the mechanism and design of the appropriate management of their pathological lesions. Several investigations have identified the anatomical and morphological differences between the medial (MMi) and lateral menisci (LMi) in humans. What remains unclear, however, is the comparative analysis of histological and histometric parameters of these menisci, especially between males and females. To evaluate and compare the different histological, histometric and biochemical parameters of different structural components (collagen, proteoglycans, cellularity, and vascularity) of MMi and LMi in male and female human cadavers, twenty-four knee joints, 12 males and 12 females, were dissected, and the menisci were excised and labeled. The middle region of each meniscus was cross-sectioned and subjected to different histological, histometric and biochemical studies. Histological examination of MMi and LMi in both males and females yielded several observations regarding different meniscal components; the orientation of collagen fibers was circumferential with intermingled radial fibers. Both fibroblasts and fibrochondrocytes were arranged singly or in rows alongside the direction of the collagen fibers. Also, the blood vessels were present toward the periphery, whereas the proteoglycans-rich areas were more evident in the inner region of each meniscus. Nevertheless, collagen fibers organization, safranin-O staining intensity, and cellular arrangement were all different between males and females. The analysis of these changes was further compared histometrically between MMI and LMi in males and females. The gained comparative histological, histometric and biochemical findings of this work are critical for providing detailed information on the microstructure and composition of both MMi and LMi in males and females. The present results also highlight the detrimental effects of histological structure on different meniscal injuries.

On the mechanical significance of vascular imprints of the human neurocranium when impacted at 11 m/s

The course of the middle meningeal vessels can be traced through imprints on the inner table of the human neurocranium. It is as yet unexplored whether these notches lower the load-bearing capacity of the bone when compared to areas that are free of vascular imprints. Here, 310 temporo-parietal samples with and without vascular imprints, from 52 human Crosado-embalmed cadavers, were tested in a three-point bending setup with a half-cylindrical impactor (1 mm radius of curvature) contacting the sample at 11 m/s. The maximum forces before breaking, and the thicknesses of the samples, were statistically compared, including comparing the avascular group to several groups with vascular imprints of different orientations. Furthermore, the influence of sample length and impact location were investigated. To investigate structure and mechanical function of vascular imprints concomitantly, scanning electron microscopy was performed on selected samples in two different planes. The results showed that avascular samples were on average thicker (p < 0.001) and stronger (p ≤ 0.050) compared to samples with vascular imprints. When only thickness-matched samples were analysed, the observed maximum forces of vascular and avascular samples were statistically similar (p ≥ 0.531). Regarding the load-bearing capacity of samples with vascular imprints, it was irrelevant whether the imprint was placed parallel to and directly underneath the impactor, parallel to and offset from the impactor, or perpendicular to the impactor (p > 0.999). The overall results of this study were statistically unrelated to both sample length (p ≥ 0.720) and impact location (p > 0.999). Scanning electron microscopy revealed that vascular imprints are formed through a curve of the inner table. Perforating holes of the inner table are present in avascular areas, however, they are considerably larger in size and higher in number within vascular imprints. In conclusion, vascular imprints are formed through curving of the inner table. In numerical models of human head mechanics, vascular imprints can be accounted for through a simple thinning of the bone assuming the same load-bearing capacity as for the surrounding imprint-free areas.

Variations in arterial sources and supply patterns to the human trigeminal ganglion with clinical significance

IntroductionTrigeminal ganglia (TG) are bilateral collections of cell bodies from the first-order pseudounipolar neurons in each trigeminal nerve. Branches of the internal carotid artery (ICA), middle meningeal artery (MMA), accessory meningeal artery (AMA), and superior cerebellar artery (SCA) have been known to supply the TG, but information about the prevalence and patterns of these vessels supplying the TG is limited despite their important clinical relevance to basicranial surgeries. The objective of this study is to investigate the arterial sources and supply patterns to the TG and discuss their clinical implications. MethodsGross arterial sources and supply patterns were examined on 139 TG from 90 embalmed human cadavers from ethically approved anatomical donor programs. Select specimens were photographed, and color replacement was utilized to aid structure identification. Vascular histology was examined with light microscopy and photographed on one specimen for methods validation. ResultsOne hundred and one TG (72.7%) received arterial supply from a single source: 71 (51.1%) from ICA, 18 (12.9%) from AMA, and 12 (8.6%) from MMA. Thirty-seven TG (26.6%) exhibited two distinct arterial sources from ICA, AMA, or MMA in either anastomotic (n = 25; 18.0%) or dual-independent (n = 12; 8.6%) patterns. One TG (0.7%) received supply from ICA, AMA, and MMA in a complex pattern. No gross arterial supply from SCA was found. ConclusionsThe TG is predominantly supplied by ICA (prevalence = 76.3%), though AMA and MMA also represent considerable contributions (31.7% and 20.1%, respectively) in various supply patterns. The TG arterial sources and supply patterns reported in this study should be considered when deliberating treatment of meningiomas, schwannomas, and dural arteriovenous fistulas within and around Meckel's cave.