Anatomy and Histology

Permanent URI for this community

https://scholar.sun.ac.za/handle/10019.1/138

Browse

Browsing Anatomy and Histology by browse.metadata.advisor "Greyling, L. M."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    The correlation between cranial and post-cranial skeletal elements for resolving and reconstruction of comingled skeletal remains in victim identification
    (Stellenbosch : Stellenbosch University, 2019-04) Marais, Johan Christian; Alblas, Amanda; Greyling, L. M.; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences: Anatomy and Histology.
    ENGLISH ABSTRACT: Upon discovery of comingled disarticulated skeletons, actual matching of different skeletal elements to a particular individual can be extremely difficult. Available literature regarding the matching of skeletal elements, show few studies correlating skull measurements with post-cranial elements, with the majority of cases determining correlations with stature. The aim of this study is to assess the degree of correlation between cranial and post-cranial skeletal elements, of the three dominant South African population groups, by means of direct correlations of measurements. Skeletons of individuals (N=296) of both males (n=148) and females (n=148) of South African black (n=100), South African white (n=97) and South African coloured (n=99) population groups, were assessed in three distinct manners. Firstly, three correlation sets were recorded: 21 cephalometric elements were correlated with eight long-bone measurements, and six occipital condyle measurements with morphologically mirrored measurements on the superior articular facet of the first cervical vertebra were correlated. The last of the correlation sets consisted of the lengths and breadths of the neural foramina from foramen magnum up to C2. Secondly, Principal Component Analyses were conducted on the 21 cephalometric elements, the eight long-bones measurements, the 12 articular facet measurements, and the six neural canal measurements. Lastly, t-tests were conducted to determine if any of the measurements were sexually different. From these assessments, a connection between some of the cephalometric elements and the long bones were observed. Most notably, the novel construct known as representative facial height (NLH.MRH), which is the summation of the nasal height and the maximum ramus height of the mandible for all three population groups. The South African white males, however, showed a much weaker connection with NLH.MRH, though, the basion-bregma height correlated well with the long bones. It was determined that the length measurements outperformed the breadth measurements in terms of correlative strength for the three population groups, in the atlanto-occipital joint. A direct relationship was established within the neural canal from foramen magnum up until C2 for all three population groups. A clear platform is created for future research into constructing regression formulae for matching skulls with long bones. The articular facet and neural canal results can be used in a combined assessment for matching a skull with a body that has an intact cervical spine, by developing a regression model from a grouping of both measurement sets. These regression models may then be implemented in the sorting of comingled remains in situations such as mass graves and mass disasters.
  • Thumbnail Image
    Item
    The sciatic nerve division in the gluteal region in a South African population: An anatomical study
    (Stellenbosch : Stellenbosch University, 2019-04) Bergsteedt, Bryan Jason; Greyling, L. M.; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Biomedical Sciences: Anatomy and Histology.
    ENGLISH ABSTRACT: The sciatic nerve is repeatedly involved in the daily medical practices of anaesthesia, neurology, orthopaedics and rehabilitative medicine. The sciatic nerve, and its branches, are some of the most frequently injured nerves within the human body. A possible reason for injury could be related to an inadequate knowledge of the anatomical variations of this nerve. Adequate understanding of the anatomical variability within the gluteal region is vital for appropriate diagnosis, potential treatment of gluteal pathology and pain and population-specific anomalies. To the author’s best knowledge, no previous study has described the anatomical variations in relation to the piriformis and sciatic nerve bifurcation within the South African population. Therefore, the aim of the study is to report the prevalence of anatomical variations within the course of the sciatic nerve in relation to the piriformis muscle. Additionally, to report the prevalence of the variations in the level of the sciatic nerve bifurcation. Lastly, to analyse the typical sciatic nerve and piriformis morphomety. The results obtained will be a comparison between sides, sexes, and population groups. For the purpose of this study, lower limbs (𝑁=340) from 170 South African cadavers were selected for dissection and morphological analysis. These specimens consisted of 191 males and 149 females, and comprised of three South African subpopulation groups, namely, White/Caucasian (𝑛=232), Mixed race (𝑛=78) and South African Black (𝑛=30). The variations were recorded, classified and described. Piriformis and sciatic nerve parameters were measured morphometrically using a digital sliding calliper, and statistically analysed. Analysis of the relationship between piriformis and the sciatic nerve resulted in 43 (12.65%) specimens that presented variations in the morphology, while 297 (87.35%) specimens presented normal anatomical features. Variations of these structures occurred predominantly in the South African White/Caucasian population. The bifurcation of the sciatic nerve occurred mainly in the popliteal fossa proper (79.6%). The width of the sciatic nerve was significantly larger in the White/Caucasian group (𝑝<0.05), in comparison to the other two groups. The mean length of the sciatic nerve was significantly larger in the male specimens (𝑝<0.05) in comparison to the female specimens. It was found that the sciatic nerve commonly entered the gluteal region as a single trunk, through the infra-piriform space, inferior to the piriformis muscle. However, variations in the anatomy of the sciatic nerve are common, and are vital in assessing clinical risk, and avoiding debilitating injury or incorrect pain diagnoses. To maintain best possible clinical practices requires regularly updated clinical skills in relation to accurate and relevant new anatomical knowledge. It is for this reason that studies, such as this one, ensure that vital research contributions are available for best clinical practice. Clear uniform landmarks for morphometric analysis of the sciatic nerve and piriformis needs to be established in order to create uniformity and understanding of results. Additionally, there is a need for the increase in published literature for the South African subpopulation groups in order to strengthen comparisons and conclusions of reported research. Researchers also need to research variations in larger groups within the South African population.