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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Examination of osteoarthritis for age-at-death estimation in a modern population

Brennaman, Ashley Lindsey 24 September 2015 (has links)
Age estimation techniques have utilized cranial suture closure, the sternal rib ends, the auricular surface, and the pubic symphysis, each with varying degrees of success. Although recent research has attempted to advance methodologies for age estimation, little progress has been made in discerning forensic age ranges that are beyond general estimates, especially in the old adult (50+) cohort. Since the accuracy of current aging methods decreases as chronological age increases, degenerative changes within the skeleton could potentially yield useful data for establishing and narrowing age estimates for older individuals, especially where only limited or fragmentary remains are recovered. The purpose of the present study was to conduct a visual examination of joint surfaces typically found to be affected by osteoarthritis (OA) by the fourth decade of life using a modified version of the OA scoring system proposed by Buikstra and Ubelaker (1994). According to archaeological, forensic, and clinical research, OA is most commonly found in the shoulder, hip, and knee, making these joints ideal for use in the present study. Within these three joints, ten osseous surfaces were examined: the acromial facet of the scapula, the glenoid fossa of the scapula, the lateral clavicle, the humeral head, the acetabulum of the os coxa, the femoral head, the medial and lateral femoral condyles, and the medial and lateral facets of the patella. Evidence of lipping, surface porosity, osteophyte formation, and eburnation were recorded on an ordinal scale, along with the percentage of the joint surface that was covered by each of the aforementioned traits. The data gathered from this examination were used to create a composite scoring system for age–at–death estimation using a modern North American sample of 206 White individuals from the W. M. Bass Donated Skeletal Collection and the Boston University Donated Osteological Collection. Significance testing indicated that sex differences were not present in the current analysis. A paired-sample t–test determined that the sample was affected with statistically significant levels of bilateral asymmetry. In addition, the current method is affected by low levels of intraobserver error, with only 5% of the sample being affected. Pearson's and Spearman's correlation coefficient were used to examine the relationship between a selected variable and age. The results of the present study indicate that OA has a positive correlation with age, although some joints show weaker associations than others. The right shoulder showed the highest correlation with age (r = 0.776, rs = 0.769; p < 0.01), followed closely by the left shoulder (r = 0.753, rs = 0.753; p < 0.01). The next highest correlation with age was observed for the left knee (r = 0.545, rs = 0.568; p < 0.01), followed by the right knee (r = 0.459, rs = 0.459; p < 0.01). The lowest correlation was observed in the left hip (r = 0.414, rs = 0.377; p < 0.01) and right hip (r = 0.476, rs = 0.377; p < 0.01). Data from multiple joint surfaces were combined for statistical analysis to create composite variables for each joint. The composite variables are combinations of traits for each joint that stepwise regression demonstrated as the best indictors for narrowing prediction intervals. This created a series of composite scores for the left shoulder, right shoulder, left hip, right hip, left knee and right knee. Individual prediction intervals at the 90% confidence interval were generated to create age ranges for each composite score. The mean age and frequency of each composite score was also recorded. This multifactorial approach demonstrated that the left and right shoulders provided the narrowest prediction intervals and also possessed the highest predictive power for estimating age-at-death. Relative predictive power was determined using R^2. The R^2 value for the right shoulder was the highest at 0.603, followed closely by the left shoulder with an R^2 value of 0.567. The R^2 value for all remaining variables was less than 0.3, indicating weak predictive power. The results of the present study were then compared to the four traditional macroscopic aging techniques: suture closure, morphology of the sternal rib ends, morphology of the auricular surface and the pubic symphysis. Sample distribution, correlation data, derived age ranges and error rates were compared between previous research and the results of the present study. All age estimation techniques demonstrated a positive correlation with age. Age ranges that were derived using Bayesian statistics or individual prediction intervals are more accurate at predicting actual age than those that were generated using confidence intervals of the mean, which provide information for mean age rather than actual age. In addition, the relationship between bone density and survivability of elements is discussed. It was determined that the skeletal elements utilized in traditional macroscopic aging are prone to breakage and loss based on their bone mineral density and location within the skeleton. In contrast, the proposed method utilized areas of the skeleton which are not typically examined for aging yet are likely to survive destruction from common taphonomic forces, making the use of OA in fragmentary or damaged contexts possible. Future research is needed to address the effects of ancestral variation and interobserver on the proposed method.
2

Analysis of Osteoarthritis on Appendicular Joint Surfaces in Known Age and Sex Samples from the Terry and Spitalfields Collections

Webb, Michelle Lynn 21 April 2010 (has links)
Arthritis is one of the most common manifestations of aging and is the single largest cause of disability in the UK, US, Australia, and Canada among people age 30 years and older. Osteoarthritis of appendicular joint surfaces exhibits alterations of bony tissue in and around the joint surface. The degree to which osteoarthritis of articular surfaces occurs as a function of age and sex can be resolved with cemetery populations of known individuals, such as the Terry (19-20th century) and Spitalfields (17-18th century) collections upon which I report (n = 322; 162 males and 160 females). Using the five point scoring system 0-4 of lipping from the Chicago Standards Guide I ask whether (1) age has an influence on the accumulation of OA; (2) sex differences are present in patterns of OA; and (3) population origin is responsible for explaining intensity of OA.
3

Picking up the pieces: Utilizing the diagnostic potential of poorly preserved remains.

Brickley, M.B., Buckberry, Jo January 2015 (has links)
No / With pressures on time and resources available to those undertaking research in paleopathology, poorly preserved archaeological human remains can often receive limited attention or be completely excluded from the analysis of archaeological sites. Although incomplete skeletons often yield minimal demographic information and can complicate the diagnosis of some pathological conditions, this is not universal. Significant information can be obtained even in partial remains on metabolic bone diseases (where, by definition, the whole skeleton is involved), and for conditions such as osteoarthritis and fractures which can be diagnosed in isolation. We present an example of an incomplete skeleton that provided valuable new information on pathological changes associated with osteomalacia, a condition that has been little studied to date in paleopathology. This skeleton also contributes to our understanding of the factors surrounding the classification of fractures, and provides new insight into the full range of circumstances in which eburnation can develop. This example demonstrates the value of including partial and poorly preserved skeletons in paleopathological analysis and the extent of information that can be obtained.

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