Bone mineral density and geometric morphometrics: Indicators of growth in the immature pars basilaris.

The pars basilaris forms a central component of the immature basicranium and owing to its resilience to post-mortem and taphonomic changes, holds significance across evolutionary, clinical, and forensic contexts. While size and shape parameters of the pars basilaris have been investigated, little is known about the influence of the underlying bone mineral density on the morphometry of this bone during growth. This study aimed to investigate the development and growth of the pars basilaris with specific reference to changes in bone density patterning and development of osteological features, during the prenatal and early postnatal periods of life. A total of 109 pars basilari were sourced from the Johannesburg Forensic Paediatric Collection, University of the Witwatersrand, South Africa. The study sample was subdivided into early prenatal (<30 gestational weeks), prenatal (30-40 gestational weeks) and postnatal (birth to 7.5 months) groups and micro-CT scanned to assess bone mineral density patterns across seven regions of interest. Size and shape changes were analysed using 11 digitized landmarks and geometric morphometrics. When comparing across age groups, the assessed dimensions increased with growth manifesting as a deepening at the anterior border of the foramen magnum, development of the lateral angles and widening of the bone at the lateral projections and spheno-occipital synchondrosis. However, no significant changes in the distribution of bone mineral density were observed. An appreciation of morphological changes and bone quality at specific growth sites in the pars basilaris is essential when analyzing remains of unknown provenance for the purposes of identification in disaster victim settings.

Leading the transition to ethical human body sourcing in Africa: The South African experience.

BACKGROUND: The use of human bodies for anatomy education and research forms an integral part of the training of health professionals around the world. However, the ethical acquisition of human remains for this purpose has been a challenge in many countries, particularly for those on the African continent. South African institutions have however, been able to progressively transition to a more ethical approach to human body acquisition. The aim of the current study was to investigate the provenance of human bodies and the number used in South African health sciences institutions during the period 2017-2021. METHODS: an online self-administered anonymised questionnaire was circulated to all health sciences institutions in South Africa. Questions were focused on establishing the provenance and the associated number of bodies and body donor programmes. RESULTS: responses were received from thirteen of the fourteen South African institutions. All thirteen institutions use human bodies for teaching and research, with the majority of the institutions being reliant on bequests (77%) and family donations (62%), and less on unclaimed remains (46%). Most institutions have established body donor programmes. Four institutions were negatively affected by the effects of the pandemic. Memorial services, which continued during the pandemic, were conducted by eight of the thirteen institutions. CONCLUSION: South Africa is leading the transition to the ethical acquisition of human remains on the African continent. It is hoped that South African institutions will soon transform to the exclusive sourcing of bodies through willed donation and provide guidance and support for the other countries on the continent.

Assessing the morphology and bone mineral density of the immature pars lateralis as an indicator of age.

Age estimation is crucial when the state of personhood is a mitigating factor in the identification of immature human remains. The maturation sequence of immature bones is a valuable alternative to dental development and eruption standards. Bordering the foramen magnum and pars basilaris, the pars lateralis is somewhat understudied. The aim of this study was to comprehensively describe the morphology of the immature human pars lateralis bone. Human pars laterali were sourced from the crania of 103 immature individuals of unknown provenance from the Johannesburg Forensic Paediatric Collection (JFPC), University of the Witwatersrand (HREC-Medical: M210855). The study sample was subdivided into early prenatal (younger than 30 gestational weeks; n = 32), prenatal (30-40 gestational weeks, n = 41) and postnatal (birth to 7.5 months, n = 30) age groups. The morphology of the pars laterali was studied using a combination of bone mineral density pattern assessments, geometric morphometrics and stereomicroscopy. Bone mineral density in postnatal individuals was lower when compared with the prenatal individuals. No statistically significant differences between density points were noted. The overall shape of the pars lateralis changed from a triangular shape in the early prenatal individuals to a fan-like quadrilateral bone in postnatal individuals. The angulation of the medial border for the foramen magnum highlighted a change in shape between straight in the early prenatal cohort to V-shaped in the postnatal individuals. The various technical approaches used in the current study provided detailed descriptions of the pars lateralis which establishes a valuable foundation for diagnostic criteria employing morphological predictors for biological profiling.

The ethical use of digital technology in teaching anatomy: A southern African perspective.

BACKGROUND: The use of 21st Century technology in anatomy teaching and the recent crisis caused by the Coronavirus pandemic has stimulated anatomists to ponder the ethics surrounding the utilisation of digital images from human bodies of known and unknown provenance in teaching. AIM: This novel study explores the awareness of southern African anatomy educators regarding the provenance and ethical use of human material in digital resources for E-learning purposes. MATERIALS AND METHOD: Anatomy educators (both members and non-members of the Anatomical Society of Southern Africa including postgraduate students in anatomy) located in 15 health sciences facilities in southern Africa were asked to participate in the survey which consisted of an anonymous, cross-sectional, questionnaire conducted on an online research data system, REDCap. RESULTS: While 52% of respondents used E-learning resources sourced from their own departments for teaching, only 58% of these had knowledge of the provenance of the human material used. Of the 72% of respondents using images from external E-learning resources, 64% did not know the provenance of the human material in these resources. Some southern African anatomists considered anonymity as equivalent to informed consent. Regarding the acceptability of unclaimed bodies for online images, 37% of respondents were against the use of these bodies, while 20% indicated that it was acceptable. Personal internal moral conflict was acknowledged regarding the use of material from unclaimed bodies, particularly during crises such as the Coronavirus pandemic when digital resources were limited. DISCUSSION AND CONCLUSIONS: Factors such as lack of awareness of provenance, the law in South Africa and using anonymity for consent, influence the ethical behaviour of southern African anatomists. Clear guiding principles would be of value for anatomists globally with respect to consent to the taking and distribution of images, and transparency on the source of the digital images provided in digital texts and online platforms. The establishment of both an oversight and ethics committee at institutions where digital imaging will be used is recommended.

A morphometric analysis of the immature human infraorbital canal.

PURPOSE: The importance of the infraorbital canal in the growth of the maxilla and associated mid-facial region has significance for innervation of this region as well as the associated dentition, yet little is known about the development of the canal. An analysis of its dimensions and morphology during the late prenatal and early postnatal periods was thus undertaken. The aim of this study was to describe changes in the morphology, size and branching pattern of the infraorbital canal during the late prenatal and early postnatal stages of human growth. METHODS: Fifty human fetal and neonatal maxillae were analyzed. The sample included 27 late prenatal individuals (30 gestational weeks and birth) and 23 early postnatal individuals (birth and 1 year). Maxillae were scanned using a Nikon XTH 225 L micro-CT unit and analyzed using VG studiomax v3.2. Measurements included the maximum width, height and surface area of each foramen associated with the infraorbital canal and the total length of the canal, bilaterally. RESULTS: All the measurements of the canal were greater in the early postnatal group than in the late prenatal group, while the walls and branching pattern of the canal were better developed in the postnatal group. Bone development occurred within the walls as development proceeded. Variations in the branching pattern of the canal were found. CONCLUSION: The morphology of the infraorbital canal reflected the developmental stage of associated structures such as the dentition, maxillary sinus and orbit.

The altered profile of a donated cadaver population: challenges for teaching and research?

Efforts by anatomists over the recent past, have converted the cadaver population in a South African institution from a predominantly unclaimed population into one purely derived from donors. Concurrent with this transformation were noticeable changes in cadaver demographics, which raised concerns for aspects of teaching and research. The aim of this study was therefore to explore the effects of donation on the demographics and anatomical integrity of the School's 2017 cadaver population. The provenance, ancestry, sex and age of 74 cadavers were investigated. Dissected cadavers were studied to ascertain the general condition of their anatomy. Variations in tissue integrity, morphology and overt pathologies were surveyed. Cadavers represented only one population group with slightly more females (54%). The majority of the cohort (62%) was aged between 71 and 90 years. With regards to anatomical integrity, 60% of the cadavers presented with adhering fascia, but no significant differences in the quantity of fat were found across the sample. High levels of muscle tearing and atrophy (76%) occurred and variations in visceral anatomy were noted. Various surgical interventions and overt pathologies were also observed. The donated cadaver population differed from previous unclaimed cadaver populations in that they consisted of only White, older individuals. Variations, surgical interventions and pathologies offer staff in anatomy an opportunity to engage with more clinically-oriented teaching, as well as introducing students to the discipline of gerontology

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Supporting early career anatomists: An international challenge.

INTRODUCTION: The formative years in academia are difficult for early career academics as they transition into their new roles in teaching and research. Ubiquitous changes in health sciences education have compounded this transition for early career anatomists (ECA), who must balance curriculum transformations, research imperatives and administrative responsibilities as they navigate their transition. Support for ECAs is thus important in order to provide a strong pipeline of anatomists for the future of the discipline and its foundational role in the health sciences. Thus, this study investigated the needs of international ECAs with respect to teaching, research and career/professional development in the anatomical sciences. METHOD: The authors distributed an online survey in 2018 to ECAs of member associations of the International Federation of Association of Anatomists (IFAA). The survey contained both closed and open-ended response questions. Data gathered included ECAs level of academic appointment, training for teaching and nature of support that ECAs may find valuable for their development as anatomists. Frequencies and 95% confidence intervals were calculated and answers to open-response questions were analysed qualitatively. RESULTS: Over 590 respondents from across the globe answered the survey. Requests for training in the clinical relevance and application of anatomical sub-disciplines were frequent. Importantly, support to establish collaborations, mentorship relationships and professional networks were repeatedly requested. CONCLUSION: In this first ever international survey of ECAs, the needs expressed by respondents indicate the importance of academic and professional development support at both local and global levels. Partnerships between the IFAA, institutions, anatomical and educational associations should create training and mentoring opportunities to smooth the transition into academia for these young academics, which would ensure the future of the discipline and its role in the health sciences.

The Law, Ethics and Body Donation: A Tale of Two Bequeathal Programs.

Historically, legislature has been utilized to facilitate appropriate use of cadavers in the anatomical sciences. However, cadaver acquisition and use have also been guided by ethically appropriate and morally acceptable principles. Various global and regional frameworks of "ethical practice" guide body donation, including the use of unclaimed bodies by institutions. These frameworks are responsive to, and reciprocal with the various ethical, moral and legal factors that influence the development of body donation programs. This reciprocity supports the notion that anatomists and anatomical societies have a responsibility to advocate for legal reform when required. In this study, two body bequest programs from geopolitically and socially disparate countries are used as cases to contrast existing legal and governance frameworks for body donation and to examine whether anatomists can direct the acquisition of ethically donated cadavers. The study includes an Australian donor program that has exclusively accepted bequests since its inception, and a South African program that has recently transitioned to a bequest system. Elements such as consent by next-of-kin and Inspector of Anatomy, use of unclaimed bodies and ethics committee approval amongst others, are compared. It is acknowledged that legal frameworks for cadaver acquisition generally deliver broad guidance on acceptable utilization of bodies for the anatomical sciences. However, professional discretion is of importance in adapting to societal needs and values. Thus, while anatomists have been able to progress toward more ethical practice than that which is required by the law, they must continue to do so as societal values evolve.

An osteological assessment of cyclopia by micro-CT scanning.

PURPOSE: Imaging modalities such as micro-CT scanning and three-dimensional reconstruction are providing a mechanism for detailed analysis of skeletal components not only of normal specimens but also through revisitation of the abnormal. The aim of this study was to analyse the craniofacial skeleton of five human fetuses with cyclopia by means of micro-CT scanning and three-dimensional reconstruction. MATERIALS AND METHODS: The study consisted of five cyclopean individuals from the paediatric collection of the School of Anatomical Sciences, University of the Witwatersrand. The specimens ranged in age from 22 to 42 weeks of gestation. The osteological features of each bone of the skull were analysed with the aid of micro-CT scanning and analysis using VG studiomax software. RESULTS: A detailed analysis of all the bones of the skull revealed that the upper two-thirds of the viscerocranium and the anterior region of the basicranium were the most affected regions of the cyclopean fetuses. The ethmoid, nasal, inferior concha and the lacrimal bones were absent in all the cases of cyclopia. Major abnormalities were found in the premaxillary region which affected the development of the anterior dentition. CONCLUSION: This study supports the suggestion that the malformations of the visceral bones are secondary to defective development of the presphenoid and mesethmoid cartilages. The ethmoidal bones are important midline struts during normal development and their absence in cyclopia leads to non-laterality of facial features.

Making the Ethical Transition in South Africa: Acquiring Human Bodies for Training in Anatomy.

While dissection remains the method of choice for teaching human anatomy, ethical requirements for obtaining cadavers has made the process of acquiring human bodies more strenuous for institutions. In Africa and at the School of Anatomical Sciences in South Africa, dependence on unclaimed bodies has been prevalent. The aim of the present study was to determine whether more rigorous application of ethical consent has altered the provenance of the cadavers in the School of Anatomical Sciences, University of the Witwatersrand. The numbers of bequeathed/donated/unclaimed cadavers received over the period 2013-2017, as well as their sex and population affinity were analyzed. The majority (96.8%) of the cadavers dissected over the period were from bequests/donations. Marginally more females than males were available. In addition, the population affinity of the cadavers had changed from a majority of South African African (unclaimed) bodies to a majority of South African White (bequest/donated) bodies. The study shows that even with ethical constraints it is possible to transition from the use of mainly unclaimed bodies to the acquisition of bequeathed/donor bodies. However, there may be challenges in relation to anatomical collections in the School as few of the bequest/donated cadavers remain in the School to be added to the collections. These changes also affect the demographics of the Schools' collections.

Variations in bone density across the body of the immature human mandible.

During growth the mandible accommodates increases in biomechanical loading resulting from changes in the function of structures of the oral cavity. Biomechanical loads are thought to play an intricate and vital role in the modelling and remodelling of bone, with site-specific effects on bone mineral density. It is anticipated that the effects of this loading on bone mineral density are intensified during the functional transition from prenatal to postnatal stages. The aim of this study was thus to evaluate changes in bone mineral density across the body of the immature human mandible during the early stages of dental development. The study sample included 45 human mandibles, subdivided into three age groups: prenatal (30 gestational weeks to birth; n = 15); early postnatal (birth to 12 months; n = 18); and late postnatal (1-5 years; n = 12). Mandibles were scanned using X-ray micro-computed tomography. Eight landmarks were selected along the buccal/labial and lingual surfaces of each dental crypt for evaluation of the bone mineral density. Bone mineral density values were calculated using a reference standard and analysed using multivariate statistics. The bone mineral density of the lingual surface was found to be significantly higher (P ≤ 0.000) than that of the buccal/labial surface. Furthermore, bone mineral density in the alveolar region of the buccal/labial surface of the deciduous central incisor (P ≤ 0.001), the deciduous first molar (P ≤ 0.013) and lingual alveolar area of the deciduous second molar (P ≤ 0.032) were significantly greater in the early postnatal period than in the prenatal period. While changes in bone mineral density across the lingual surface were consistent with the progression of development and the biomechanical demand of the tongue as previously demonstrated, changes observed across the buccal/labial surface of the mandible appeared to accompany the advancing dental development. Thus, changes in bone mineral density across the mandible appear to be reflective of the stage of dental development and the level of biomechanical loading.

Importance of teeth in maintaining the morphology of the adult mandible in humans.

Edentulism can negatively affect both masticatory performance and dietary intake by altering the patterns of biomechanical stress and strain, which in turn modifies the morphology of the different regions of the mandible. The morphological changes in the mandible caused by these stressors are unknown when comparing mandibles across varying dentition states. This study investigated differences in the morphology of human mandibles across various states of the dentition. In total, 498 mandibles of individuals between 20 and 80 yr of age at death were sourced from the Raymond A. Dart Collection of Human Skeletons. These included fully dentate (n = 95), partially edentulous (n = 333), and fully edentulous (n = 70) mandibles. Twelve linear anthropometric measurements of the mandible were derived from digitized landmarks located on its external surface. Data analysis included geometric morphometrics and multivariate analyses. Compared with dentate and partially edentulous mandibles, fully edentulous mandibles showed a shorter alveolar height (-0.4 mm), a shorter mandibular body length (-4 mm), a larger gonial angle (+4°), a more obtuse mental angle (+4.7°), a broader bicondylar width (+3.8 mm), and a taller ramus height (+1.6 mm). Thus, edentulous states are associated with an altered mandibular morphology, which may result from a reduction in jaw function.

Transformation of a cadaver population: Analysis of a South African cadaver program, 1921-2013.

Anatomy has served as a cornerstone in the training of various allied and clinical disciplines and has traditionally been based on dissection of the human body. Thus, to pursue this method of teaching and learning, access to cadavers is of continuing importance. Over a significant period of time unclaimed cadavers have performed an essential role in the teaching of anatomy in South Africa and in Africa. As recent cadaver numbers were declining at the School of Anatomical Sciences, University of the Witwatersrand, Johannesburg and difficulty in procurement was being experienced, the purpose of this study was to critically evaluate the composition of our cadaver population over time so as to provide possible strategies to arrest the decline. A retrospective, quantitative analysis of cadaver records from the School of Anatomical Sciences between 1921 and 2013 was undertaken. Analysis included a comparison of Poisson counts and Fischer's exact test. A significant decrease in the number of cadavers received during the period 2000-2013 and a slow bequest program over the same period of time has led to concerns about the sustainability of teaching anatomy through dissection. Decreases in the numbers of males and cadavers of the black population group occurred between 1990 and 2013, and of bequests from 2000 to 2013. An influence on the cadaver population from a changing political climate and change in socioeconomic status of part of the population was perceived. Changes in sex and population group of the cadavers may have a long-term effect on teaching and research.

Morphometric growth relationships of the immature human mandible and tongue.

The masticatory apparatus is a highly adaptive musculoskeletal complex comprising several relatively independent structural components, which assist in functions including feeding and breathing. We hypothesized that the tongue is elemental in the maintenance of normal ontogeny of the mandible and in its post-natal growth and development, and tested this using a morphometric approach. We assessed tongue and mandibular measurements in 174 (97 male) human cadavers. Landmark lingual and mandibular data were gathered individuals aged between 20 gestational weeks and 3 yr postnatal. In this analysis, geometric morphometrics assisted in visualizing the morphometrical growth changes in the mandible and tongue. A linear correlation in conjunction with principal component analysis further visualized the growth relationship between these structures. We found that the growth of the tongue and mandible were intrinsically linked in size and shape between 20 gestational weeks and 24 months postnatal. However, the mandible continued to change in shape and size into the 3rd yr of life, whereas the tongue only increased in size over this same period of time. These findings provide valuable insights into the allometric growth relationship between these structures, potentially assisting the clinician in predicting the behaviour of these structures in the assessment of malocclusions.