Exploring age-related trends in cortical and trabecular bone in an elderly Scottish sample:a pilot study on the clavicle

The human lifespan is increasing globally, increasing the need for further research on age-related changes inthe bone of elderly individuals. Microscopic assessment of the skeletal system can provide information aboutthe composition, mechanical, and functional properties of bone. The aim of this study is to combine 2D and3D approaches examining cortical and trabecular bone to explore histological age-related changes in theclavicles of an elderly Scottish population.The medial portion of 30 left clavicles was collected from Scottish donors from the Centre of Anatomy andHuman Identification. The sample had a mean age of 83 years, with a sex distribution of 15 males and 15females. Histomorphometric variables from the trabecular and cortical bone were collected. Five trabecularparameters were assessed using micro-CT scanning on two volumes of interest (VOI-superior and inferiorsampling locations on the medial clavicular end). On the cortical bone, fourteen parameters were evaluatedusing traditional histological techniques. Cortical area related parameters were assessed on the whole crosssection, while osteon frequency related variables were measured on 8 sampling areas targeting keyanatomical locations on the periosteal section of the clavicle.Intra-observer error was assessed using intra-class correlation coefficient. The two VOIs were compared forstatistical differences using paired t-test or Wilcoxon signed-rank test. Pearson and Spearman correlationcoefficients were calculated, and age group comparisons were conducted for all parameters on the entiresample, the sample divided by decades (70s, 80s, and 90s), and the sample divided into two age groups(over/under 85 years). Sex differences were explored using an independent t-test and Mann-Whitney test.Lastly, stepwise regression analysis was used to test the optimal combination of parameters that couldexplain the highest variation in age.Intra-observer error demonstrated overall good reliability for most parameters. Only bone volume fractiondid not differ between VOIs, with all other trabecular parameters showing statistically significant differences.Cortical area parameters (cortical area and relative cortical area), intact osteon number, and both VOIs fortrabecular connectivity density were statistically significantly correlated to age. When the sample was splitinto decades, no significant changes were observed over the three decadesfor cortical bone parameters (70s,80s, and 90s). However, trabecular thickness and bone volume fraction differed statistically betweenindividuals in their 70s and 80s. When the over/under 85 years groups were compared, only relative corticalarea was statistically different between the two groups. Sex differences were found for cortical area relatedparameters (total area, endosteal area, and cortical area). Stepwise multiple linear regression showed thatrelative cortical area and inferior trabecular connectivity accounted for 30% of the variation in age.This research showed that combining both cortical and trabecular bone using histomorphometric parameterscan provide valuable information about age-related changes, suggesting also that other factors such as sexor age-related pathologies might have an impact on the changes observed in the two bone tissue types. Whilefurther research is necessary, this study adds to the growing research on bone histology using differentpopulations and exploring the ageing patterns of an elderly population

Exploring age-related trends in cortical and trabecular bone in an elderly Scottish sample:a pilot study on the clavicle

The human lifespan is increasing globally, increasing the need for further research on age-related changes inthe bone of elderly individuals. Microscopic assessment of the skeletal system can provide information aboutthe composition, mechanical, and functional properties of bone. The aim of this study is to combine 2D and3D approaches examining cortical and trabecular bone to explore histological age-related changes in theclavicles of an elderly Scottish population.The medial portion of 30 left clavicles was collected from Scottish donors from the Centre of Anatomy andHuman Identification. The sample had a mean age of 83 years, with a sex distribution of 15 males and 15females. Histomorphometric variables from the trabecular and cortical bone were collected. Five trabecularparameters were assessed using micro-CT scanning on two volumes of interest (VOI-superior and inferiorsampling locations on the medial clavicular end). On the cortical bone, fourteen parameters were evaluatedusing traditional histological techniques. Cortical area related parameters were assessed on the whole crosssection, while osteon frequency related variables were measured on 8 sampling areas targeting keyanatomical locations on the periosteal section of the clavicle.Intra-observer error was assessed using intra-class correlation coefficient. The two VOIs were compared forstatistical differences using paired t-test or Wilcoxon signed-rank test. Pearson and Spearman correlationcoefficients were calculated, and age group comparisons were conducted for all parameters on the entiresample, the sample divided by decades (70s, 80s, and 90s), and the sample divided into two age groups(over/under 85 years). Sex differences were explored using an independent t-test and Mann-Whitney test.Lastly, stepwise regression analysis was used to test the optimal combination of parameters that couldexplain the highest variation in age.Intra-observer error demonstrated overall good reliability for most parameters. Only bone volume fractiondid not differ between VOIs, with all other trabecular parameters showing statistically significant differences.Cortical area parameters (cortical area and relative cortical area), intact osteon number, and both VOIs fortrabecular connectivity density were statistically significantly correlated to age. When the sample was splitinto decades, no significant changes were observed over the three decadesfor cortical bone parameters (70s,80s, and 90s). However, trabecular thickness and bone volume fraction differed statistically betweenindividuals in their 70s and 80s. When the over/under 85 years groups were compared, only relative corticalarea was statistically different between the two groups. Sex differences were found for cortical area relatedparameters (total area, endosteal area, and cortical area). Stepwise multiple linear regression showed thatrelative cortical area and inferior trabecular connectivity accounted for 30% of the variation in age.This research showed that combining both cortical and trabecular bone using histomorphometric parameterscan provide valuable information about age-related changes, suggesting also that other factors such as sexor age-related pathologies might have an impact on the changes observed in the two bone tissue types. Whilefurther research is necessary, this study adds to the growing research on bone histology using differentpopulations and exploring the ageing patterns of an elderly population

Understanding ageing in the elderly:a combined histomorphometric approach to cortical and trabecular bone in the clavicle

Bone can be assessed microscopically to further understand changes in material and mechanical tissue properties occurring with advanced age. This study investigates age-related histomorphometric changes in the cortical and trabecular bone of the clavicle in later life.Thirty sternal end left clavicles were collected (mean age = 83 years, 15 males, 15 females, Scottish population). Five trabecular variables were collected through microcomputed tomography considering two volumes of interest (VOIs: superior and inferior). Fourteen cortical bone parameters were evaluated using traditional histology, with eight periosteal locations considered for osteonal parameters. Intra-observer error was assessed using intra-class correlation coefficient. Correlations between age and parameters were calculated, and comparisons between age groups (by decades and under/over 85 years of age) and the sexes were conducted. Linear regression assessed the relationship between the parameters and age.Repeatability was overall attained. Only trabecular bone volume fraction did not differ between VOIs. Significant correlations to age were found for cortical area parameters, intact osteons, and connectivity density. Trabecular thickness and bone volume fraction differed between the 70s and 80s groups. Differences were found for under/over 85-year-old individuals for relative cortical area and between the sexes for cortical area. Relative cortical area and trabecular inferior connectivity explained 30% of the variation in age.As the global population gets older, it is crucial to further explore bone age-related changes in the elderly. This study reports age patterns for both cortical and trabecular bone potentially explained by age-related pathologies, biomechanical changes, and physiological alterations accumulating with age