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We studied the bone and dental histology of the tri-dactyl equid Eurygnathohippus hooijeri , one of the most iconic mammals found at the world-renowned Pliocene site of Langebaanweg, South Africa, to reconstruct important features of its life history. Our results show that key life-history events, such as weaning, skeletal maturity and reproductive maturity, occurred later in this African hipparionine compared with European three-toed equids and several extant Equus. Its late life-history schedule agrees with an ecological context of low adult extrinsic mortality and low juvenile survival rates. We also observed high rates of bone growth in Eu. hooijeri that were probably achieved through a high-quality diet and plentiful available water. Our research highlights the significance of combining bone and dental histology in the same taxon to obtain refined palaeobiological information about extinct vertebrates. [ABSTRACT FROM AUTHOR]

Introduction: children with spinal tuberculosis (TB) are at risk of kyphotic deformity both during and after the active phase of the disease. Management guidelines include follow-up until skeletal maturity. Little is known about adherence to this recommendation. This study aimed to investigate loss to long-term spine clinic follow-up (LTFU) among children with spinal TB at a tertiary hospital in the Western Cape Province, South Africa. Methods: this retrospective cohort study included all children diagnosed with spinal TB at Tygerberg Hospital between January 2012 and December 2015. Spine clinic follow-up was investigated for five years following diagnosis. Relevant surgical interventions and re-presentation were evaluated until 31st December 2020. Results: thirty-two children, median age 6 years (range 1-14 years), were diagnosed with spinal TB and intended for spine clinic follow-up. Twenty-seven (84%) children were LTFU within five years of diagnosis with 16 (50%) LTFU within 10.5 months. Among children in follow-up, one child had further surgery for progression of deformity two years from diagnosis and one child had further surgery for new-onset neurological deficit eight years from diagnosis. Conclusion: most children with spinal TB did not receive the recommended follow-up until skeletal maturity. Without further data on these children, the clinical significance of this LTFU could not be evaluated. Further studies are needed to investigate sequelae during skeletal maturation in the context of current management for paediatric spinal TB. [ABSTRACT FROM AUTHOR]

Provelosaurus americanus from the Guadalupian of Brazil, is the only species of pareiasaur known from South America and its studies are limited to anatomical descriptions. Here, we examined the microstructure of limb bones, a rib fragment and osteoderms of P. americanus, aiming to answer questions related to its paleobiology. The bone tissues of this specimen comprise poorly vascularised parallel-fibred bone interrupted by growth marks indicating slow, cyclical growth. This is consistent with the pattern found in other pareisaurs from South Africa. However, the space between the LAGs are irregular and there is no clear decreasing in vascularity toward the periphery of the bone, suggesting that it did not reach skeletal maturity. The highest number of LAGs was found in the rib, suggesting that our sample lived a minimum of fifteen years. The osteoderms present a trilaminar structure consisting of a diploe composed of a cancellous core surrounded by two cortical layers. A diploe is absent from the osteoderms of previously studied South African pareiasaurs. The osteogenesis of the osteoderms is intramembraneous, but a metaplastic ossification during the early developmental stage cannot be entirely discarded, due to extensive remodeling in the central core that could have destroyed potential metaplastic tissue. [ABSTRACT FROM AUTHOR]

Several studies have indicated that the time of onset of specific age-related changes throughout the human skeleton differs between populations. In this study the well-known Suchey-Brooks pubic symphyseal age estimation method was investigated to assess its performance in a white South African population. A total of 184 well-preserved os coxae were subjected to blind phase analysis, using the Suchey-Brooks descriptions and pubic symphyseal casts. The method performed well in a white South African population with statistically significant moderate positive correlations and relatively low biases in both males and females. However, due to the underperformance of the method in older individuals, new age ranges for phases IV through VI were created that are specific to the South African white population. This study indicated that Suchey-Brooks method can be used in a white South African population using the age ranges for phases I through III provided by Brooks and Suchey (1990), and the population specific age ranges for phase IV and V provided in this study. [ABSTRACT FROM AUTHOR]

The use of bone mineral density (BMD) to predict age-at-death in skeletal remains provides a usable alternative to other methods because the values obtained are not observer-dependent. The aim of this study was to investigate the usability of BMD to estimate age in South African populations, and to assess inter-population variation and sex-specific differences in BMD values from the proximal end of the femur. In order to estimate age, regression analysis was done for the construction of population dependent formulae. The sample comprised of a total of 123 femora of black and white South Africans. DXA scans were performed using the Hologic Discovery system. Data analysis was done by employing independent-samples t-tests and correlation/regression analyses. The results indicated a statistically significant difference between black and white South Africans. Male groups were also significantly different from one another, but black and white females showed no significant differences. Linear regression analysis revealed a significant correlation between BMD values and age for the white population and the combined sample, but not for the black population. Bootstrapping were employed to confirm validity of the results. In conclusion, this study showed that the use of DXA measurements of the femur for estimating age may be used for the estimation of age-at-death in white South Africans, but more research is needed to better understand the relationship between bone mineral density and age in black South Africans. [ABSTRACT FROM AUTHOR]

Aim To examine ethnic and sex differences in the pattern of skeletal maturity from adolescence to adulthood using a novel longitudinal analysis technique (SuperImposition by Translation And Rotation (SITAR)). Setting Johannesburg, South Africa. Participants 607 boys and girls of black as well as white ethnicity from the Birth to Twenty bone health study, assessed annually from 9 to 20 years of age. Outcome measure Bone maturity scores (Tanner-Whitehouse III radius, ulna, and short bones (TW3 RUS)) assessed longitudinally from hand-wrist radiographs were used to produce individual and mean growth curves of bone maturity and analysed by the SITAR method. Results The longitudinal analysis showed that black boys matured later by 7.0 SE 1.6 months (p<0.0001) but at the same rate as white boys, whereas black girls matured at the same age but at a faster rate than white girls (by 8.7% SE 2.6%, p=0.0007). The mean curves for bone maturity score consistently showed a midpubertal double kink, contrasting with the quadratic shape of the commonly used reference centile curves for bone maturity (TW3). Conclusions Skeletal maturity was reached 1.9 years earlier in girls than boys, and the pattern of maturation differed between the sexes. Within girls, there were no ethnic differences in the pattern or timing of skeletal maturity. Within boys, however, skeletal maturity was delayed by 7 months in black compared with white ethnicity. Skeletal maturation, therefore, varies differentially by sex and ethnicity. The delayed maturity of black boys, but not black girls, supports the hypothesis that boys have greater sensitivity to environmental constraints than girls. [ABSTRACT FROM AUTHOR]

Background: Secular trends are usually monitored through changes in size and earlier maturation. Skeletal maturity has rarely been used as a biological indicator of secular trend. Aim: To observe secular changes in the skeletal maturity of urban South African adolescents between 1962 and 2001. Subjects and methods: Data from the Pretoria National Nutrition Survey were compared with a cross-sectional survey of children from the Johannesburg-Soweto based Birth to Twenty birth cohort study. Adolescents aged 9-11 years from each survey were included in the analysis. Skeletal maturity was assessed using the Greulich-Pyle technique. Height, weight, triceps and subscapular skinfolds were also measured. Results: The skeletal maturity of white males and females in 2001 was in advance of the 1962 cohort by an average of 3.4 months and 2.0 months, respectively. Black males and females in 2001 were significantly in advance of the 1962 cohort by an average of 9.7 months and 15.8 months, respectively (p<0.01). Conclusion: Significant secular increases in the skeletal maturity of urban black South African children occurred between 1962 and 2001. Non-significant increases were seen in white children. The significant secular increases were concordant with increases in stature and adiposity during this period. The increase in skeletal maturity may reflect the removal of growth constraint, particularly in black children. [ABSTRACT FROM AUTHOR]

Examines the accuracy of the revised maxillary suture method in estimating the age and death on a genetically diverse skeletal sample of maxillae in South Africa. Process of age estimation based on the progressive obliteration of the maxillary sutures; Percentage of accuracy in estimating age and death of the samples; View on the usefulness of the method in skeletal identification.

The Acsádi and Nemeskéri Complex Method is a multifactorial adult age estimation method that makes use of weighting systems. The Complex Method employs the use of four skeletal elements in assessing age, including the degree of endocranial suture closure, age-related changes to the pubic symphyseal surface, and the internal structural changes observable in the proximal humerus and femur. Acsádi and Nemeskéri reported a very optimistic error margin of ±2.5 years when all four skeletal elements were used. Despite these promising results, the Complex Method's effectiveness has been questioned, suggesting that it results in a constant over- and underestimation of age in younger and older groups, respectively. In this study, the Complex Method was tested on a modern South African skeletal sample (n = 313) with individuals of known age-at-death. Results from this study to some extent justify the critique levelled against the Complex Method's tendency to over- and underestimate age. Nevertheless, the Complex Method still performed surprisingly well for certain skeletal element combinations. Contrary to Acsádi and Nemeskéri's findings, the use of all four skeletal elements did not provide more accurate age estimates. For the most part, combinations making use of three or two skeletal elements outperformed the use of all four skeletal indicators. Results from this study indicate caution in using a blanket approach when it comes to deciding on the best combination of skeletal elements used in multifactorial methods. It is suggested that the Complex Method may be optimised by making use of sex- and population-specific skeletal element combinations and weighting systems in the future. [ABSTRACT FROM AUTHOR]

Transition Analysis (TA) is an age estimation method for adult skeletons at death, using three skeletal traits together, namely, the cranial sutures (CS), the pubic symphyses (PS) and the auricular surfaces (AS). In forensic anthropology, estimating age at death is vital for positive identification of an individual; however, differences in skeletal elements have been observed between sex and population affinity. The aim of this study was to determine how accurately the TA could be applied to a population that differed from the original reference samples. Scoring methods, described by the authors of this analysis, were used to age individuals (n = 290) in the South African (SA) Mixed Ancestry population, which is a heterogenic population, consisting of many gene pools from different population groups. The results were compared to the actual ages of the skeletal remains, obtained through cadaver records, and the most likely age calculated by the TA, as well as age estimation by means of the three skeletal elements individually. Results showed that there was a significant correlation between the actual and estimated ages of the study population (Pearson correlation coefficient: 0.58). The AS was the most accurate trait, whereas the PS was the least accurate trait. In addition, females' estimated ages were more accurate than males. These findings correlated with other authors in terms of the significance of the TA when applied to different populations; however, the individual trait correlations were in disagreement with other authors. The results of this study are an important contribution to anthropological literature as they indicate that there are differences between populations and sex when determining age, but that the TA is still applicable for analysis on this heterogenic population. [ABSTRACT FROM AUTHOR]

Stereological examination of the anterior femur was done for the estimation of age-at-death. The aim of this study was to assess particular bone microstructures that change with advancing age and use these variables to create revised regression formulae applicable to the black population of South Africa. A sample of 99 bone sections (n=60 males and n=39 females) that had previously been analysed using 2D methods, were re-analysed using the optical fractionator and nucleator sampling methods. Single and multiple regression analyses were performed to assess the strength of the relationship between known age and all independent variables. For sex-pooled data, the average number of osteons per grid area (Avg_OPD) showed the highest correlation with age (r=0.528; r2=0.278), followed by average osteon volume (r=-0.383; r2=0.146). The remaining variables reflected a low correlation with age. Pooled, as well as sex-specific single regression formulae were constructed. Multiple regression formulae were constructed for pooled sexes only, as there were no significant difference between males and females overall. Although the employment of stereological methods ensured that the results are accurate and unbiased, the outcome was on par with previously reported SEE's and SD's for this population. [ABSTRACT FROM AUTHOR]

Despite indicating numerous demographic features such as sex, stature, and age; the sacrum remains a relatively insufficiently researched skeletal element. A set pattern of ossification and fusion of the sacrum makes it a useful bone for estimating age-at-death in unknown skeletal individuals. The aims of this study, which examined a black South African skeletal sample, were to establish if fusion correlated to age and to estimate the age at which fusion between the first two sacral vertebrae began and ended. A total of 316 male (n=149) and female (n=167) sacra from the Raymond A. Dart collection of Human Skeletons were assessed, with ages ranging from 13-60 years and 12-60 years respectively. A three-stage scoring method was used to categorise the degree of fusion of each sacrum. In comparison to females (rs=0.59), males demonstrated a higher correlation between age and staging score assigned (rs=0.68). It was observed that the age of partial and complete fusion was highly variable. However, it was noted that partial fusion occurred more often in individuals younger than 30 years, while complete fusion was observed commonly in both sexes above the age of 35 years. Despite this variability, the sacrum can be used as an additional age-at-death indicator. [ABSTRACT FROM AUTHOR]

Age-at-death estimation is a crucial component of any forensic anthropological analysis. Despite a variety of research in this field, uncertainties still exist when estimating adult age. The sternum is an under-considered element in terms of adult age estimation. Previous research on an Indian population suggested that this may be a usable region of the skeleton, although results were ambivalent. This study observed the fusion phases of 461 sterna from a black South African population in an attempt to match true age of an individual with the different phases of synostosis of the manubrio-sternal and the sterno-xiphoidal junctions. The results demonstrated that the majority of sterna remain unfused throughout adult life, with complete fusion observed both in young (25 year-old) and old individuals. Significant differences were identified amongst male and female sterna, with males presenting no transitional fusion of the segments, while female sterna demonstrated fusion to a lesser extent. Overall, logistic regression results demonstrated low accuracies (62.5%) for age estimation even when the two sexes were considered separately (male=63.9%; female=61.8%). The synostosis of both junctions is hence considered highly variable and deemed unreliable for adult age-at-death estimation in the black South African population. [ABSTRACT FROM AUTHOR]

Estimating age-at-death is one of the many biological demographics that a forensic anthropologist needs to determine for a set of unknown skeletal remains. A useful skeletal developmental marker, which can aid in estimating age in sub-adult remains, is the state of fusion of the spheno-occipital synchondrosis. This study aimed to determine the repeatability of a three-stage scoring method and the age at which the spheno-occipital synchondrosis begins and completes fusion in a Black South African sample. A total of 147 male and female skeletal individuals aged between 12-30 years from the Raymond A. Dart Collection of Human Skeletons were included. The mean age-at-death noted for the commencement of fusion at the spheno-occipital synchondrosis was 16.2 (±2.9) years in females and 16.7 (±1.2) years in males, with females displaying signs of fusion taking place approximately three years before their male counterparts. Complete fusion of this skeletal developmental marker was observed in 100% of the sample over the age of 20 years, regardless of sex. A Kappa value of 1.0 was achieved when the repeatability and reproducibility of the three-stage scoring method was tested. Complete fusion of this synchondrosis occurred slightly later in this South African sample than that noted in previous literature. This finding may be attributed to the differences in health and socio-economic statuses between these different population groups, reiterating the need for population-specific data to be developed. The importance of noting the state of fusion of the spheno-occipital synchondrosis during the examination of relevant forensic cases may aid in the formation of a narrower age-at-death range for sub-adult and young adult skeletal remains. [ABSTRACT FROM AUTHOR]

The use of advanced statistical methods, such as transition analysis, has transformed adult age estimation into a systematically and statistically appropriate practice. The method developed by Boldsen and colleagues (2002) uses 36 features from the cranial sutures, pubic symphysis and auricular surface to calculate maximum likelihood point estimates and 95% confidence intervals, using the ADBOU computer software. However, when using the method in a geographically and contextually distinct sample, such as South Africa, accuracy and precision is of concern. This study aimed to test the repeatability, accuracy and precision of the transition analysis method, using the ADBOU computer software, on a South African sample. Age estimations were generated, for 149 black individuals from the Pretoria Bone Collection, using three individual components as well as different combinations of components and prior distributions (uniform and informative). The informative prior distributions represented both an archaeological and a forensic context. Cohen's kappa statistic uncovered some failings in the scoring procedure. While the accuracy compared favourably with existing methods, the method lacked satisfactory precision. Although combining the components improved accuracy and precision, removing the cranium from the combination was beneficial in some instances. The influence of population variation was observed in the scoring procedure, reference sample and the prior distributions. Validity may be improved for a South African sample by adding age-related components that have been developed on a relevant population. A prior distribution based on South African mortality rates might also be beneficial. [ABSTRACT FROM AUTHOR]