Although many variables that skeletal biologists examine have been standardized, the actual tec... more Although many variables that skeletal biologists examine have been standardized, the actual techniques used to collect these data from bone thin sections vary. This project compares different methods of obtaining data (relative cortical area values) for histomorphometric research. One visual and three digital methods of histomorphometric data collection are compared: (i) Merz microscopic eyepiece counting reticule, (ii) flatbed scanner, (iii) overlaying multiple images of a thin section, and (iv) digital SLR camera with macro settings. The discussion includes a comparison of usability factors such as cost, time, user-experience, and ease-of-use, which vary for each method. Values from the different methods are compared using ANOVA tests to evaluate inter-method, inter-observer, and intra-observer variability. Intra-observer error was greater for the microscopic method, although the error values are concomitant with experience. We found no statistically significant differences between the four methods examined, but certain caveats must be addressed when these methods are used.
Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in hu... more Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in human cortical bone. While some report a decrease in On.Ar with age, other studies have found no change. The purpose of this study was to examine the correlation between On.Ar and age in a variety of bones: metacarpals (74), clavicles (n=22), ribs (n=102), tibias (n=27) and femurs (n=38). All bone samples and data were obtained from a variety of sources; archaeological excavations, dissecting room cadavers, autopsies and forensic cases. On.Ar was quantified in the mid-shaft cortex of at least 50 osteons in each bone at 200x magnification using the point count method. Recently, a study of Euro-Canadian second metacarpals determined that there was no correlation between age and On.Ar. In this study On.Ar in a sample of Inuit second metacarpals was also found not to decrease with age (r=.10). Data from clavicles (r=.29), tibias (r=.32), ribs (r=.52), and femurs (r=.72) show a negative correlation between On.Ar and age. The strength of the correlation varies from low (clavicles) to strong (femurs) and appears to be bone specific. Sex based differences are also evident with the strongest, negative, correlation between On.Ar and age in the females of each bone group. Based on our data, a decrease in osteon size with increasing age is bone specific and appears to be most evident in females.
Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in hu... more Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in human cortical bone. While some report a decrease in On.Ar with age, other studies have found no change. The purpose of this study was to examine the correlation between On.Ar and age in a variety of bones: metacarpals (74), clavicles (n=22), ribs (n=102), tibias (n=27) and femurs (n=38). All bone samples and data were obtained from a variety of sources; archaeological excavations, dissecting room cadavers, autopsies and forensic cases. On.Ar was quantified in the mid-shaft cortex of at least 50 osteons in each bone at 200x magnification using the point count method. Recently, a study of Euro-Canadian second metacarpals determined that there was no correlation between age and On.Ar. In this study On.Ar in a sample of Inuit second metacarpals was also found not to decrease with age (r=.10). Data from clavicles (r=.29), tibias (r=.32), ribs (r=.52), and femurs (r=.72) show a negative correlation between On.Ar and age. The strength of the correlation varies from low (clavicles) to strong (femurs) and appears to be bone specific. Sex based differences are also evident with the strongest, negative, correlation between On.Ar and age in the females of each bone group. Based on our data, a decrease in osteon size with increasing age is bone specific and appears to be most evident in females.
Estimating stature in human skeletal remains of Asian ancestry is problematic for forensic anthro... more Estimating stature in human skeletal remains of Asian ancestry is problematic for forensic anthropologists due to the paucity and uncertain suitability of regression formulae. To address this issue, our study analyzed 64 individuals from a modern skeletal collection of South-East Asian origin and developed population-specific ordinary least squares regression formulae to estimate skeletal height from each of the long bones of the upper and lower limbs, as well as from trunk length. Results indicate that the most accurate estimates of skeletal height from a single bone (as measured by standard error of the estimate—SEE) are from tibial length in males (SEE = 2.40 cm) and from humeral length in females (SEE = 2.59 cm), followed by femoral length (SEE = 2.84 cm). When multiple elements are considered, the combination of femoral and tibial length yields the best estimates in both sexes as well as combined sex samples (male SEE = 2.40 cm; female SEE = 2.77 cm; combined sex SEE = 2.54 cm).
Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in hu... more Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in human cortical bone. While some report a decrease in On.Ar with age, other studies have found no change. The purpose of this study was to examine the correlation between On.Ar and age in a variety of bones: metacarpals (74), clavicles (n=22), ribs (n=102), tibias (n=27) and femurs (n=38). All bone samples and data were obtained from a variety of sources; archaeological excavations, dissecting room cadavers, autopsies and forensic cases. On.Ar was quantified in the mid-shaft cortex of at least 50 osteons in each bone at 200x magnification using the point count method. Recently, a study of Euro-Canadian second metacarpals determined that there was no correlation between age and On.Ar. In this study On.Ar in a sample of Inuit second metacarpals was also found not to decrease with age (r=.10). Data from clavicles (r=.29), tibias (r=.32), ribs (r=.52), and femurs (r=.72) show a negative correlation between On.Ar and age. The strength of the correlation varies from low (clavicles) to strong (femurs) and appears to be bone specific. Sex based differences are also evident with the strongest, negative, correlation between On.Ar and age in the females of each bone group. Based on our data, a decrease in osteon size with increasing age is bone specific and appears to be most evident in females.
Skeletal histomorphometry is an important
tool for physical anthropologists
and can be used to ... more Skeletal histomorphometry is an important
tool for physical anthropologists
and can be used to estimate age and to
examine pathological conditions, activity
levels and overall health and nutrition.
In physical anthropology, measurements
most often analyze cortical bone
because of its durable nature. Although
the variables skeletal biologists examine
have been standardized, the actual
techniques used to accrue these data
from a thin section may vary. The purpose
of this research was to examine
the accuracy of newer technological
tools used to measure variables in comparison
to the standard eyepiece counting
reticule to determine whether there
was a significant variance in results
from each method. Total area (Tt.Ar.)
and cortical area (Ct.Ar.) were measured
and used to obtain a measurement
of relative cortical area (Tt.Ar/Ct.Ar.).
Three researchers with varying levels of
experience with histomorphometry compared
four methods of obtaining these
variables; one of them being the use of
a Merz1 counting reticule and three
others using the commonly used software,
ImageJ1, to measure cortical and
total area but obtaining the thin section
images in three different manners: 1)
using a flatbed scanner, 2) overlaying
multiple images of a thin section using
Photoshop1 and 3) using a digital SLR
camera with macro settings. Statistical
analyses using ANOVA indicate no significant
differences amongst observers
and the four methods examined. The
benefits and drawbacks of each method
are discussed as well as precautions one
should take while conducting histomorphometric
data collection.
Although many variables that skeletal biologists examine have been standardized, the actual tec... more Although many variables that skeletal biologists examine have been standardized, the actual techniques used to collect these data from bone thin sections vary. This project compares different methods of obtaining data (relative cortical area values) for histomorphometric research. One visual and three digital methods of histomorphometric data collection are compared: (i) Merz microscopic eyepiece counting reticule, (ii) flatbed scanner, (iii) overlaying multiple images of a thin section, and (iv) digital SLR camera with macro settings. The discussion includes a comparison of usability factors such as cost, time, user-experience, and ease-of-use, which vary for each method. Values from the different methods are compared using ANOVA tests to evaluate inter-method, inter-observer, and intra-observer variability. Intra-observer error was greater for the microscopic method, although the error values are concomitant with experience. We found no statistically significant differences between the four methods examined, but certain caveats must be addressed when these methods are used.
Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in hu... more Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in human cortical bone. While some report a decrease in On.Ar with age, other studies have found no change. The purpose of this study was to examine the correlation between On.Ar and age in a variety of bones: metacarpals (74), clavicles (n=22), ribs (n=102), tibias (n=27) and femurs (n=38). All bone samples and data were obtained from a variety of sources; archaeological excavations, dissecting room cadavers, autopsies and forensic cases. On.Ar was quantified in the mid-shaft cortex of at least 50 osteons in each bone at 200x magnification using the point count method. Recently, a study of Euro-Canadian second metacarpals determined that there was no correlation between age and On.Ar. In this study On.Ar in a sample of Inuit second metacarpals was also found not to decrease with age (r=.10). Data from clavicles (r=.29), tibias (r=.32), ribs (r=.52), and femurs (r=.72) show a negative correlation between On.Ar and age. The strength of the correlation varies from low (clavicles) to strong (femurs) and appears to be bone specific. Sex based differences are also evident with the strongest, negative, correlation between On.Ar and age in the females of each bone group. Based on our data, a decrease in osteon size with increasing age is bone specific and appears to be most evident in females.
Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in hu... more Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in human cortical bone. While some report a decrease in On.Ar with age, other studies have found no change. The purpose of this study was to examine the correlation between On.Ar and age in a variety of bones: metacarpals (74), clavicles (n=22), ribs (n=102), tibias (n=27) and femurs (n=38). All bone samples and data were obtained from a variety of sources; archaeological excavations, dissecting room cadavers, autopsies and forensic cases. On.Ar was quantified in the mid-shaft cortex of at least 50 osteons in each bone at 200x magnification using the point count method. Recently, a study of Euro-Canadian second metacarpals determined that there was no correlation between age and On.Ar. In this study On.Ar in a sample of Inuit second metacarpals was also found not to decrease with age (r=.10). Data from clavicles (r=.29), tibias (r=.32), ribs (r=.52), and femurs (r=.72) show a negative correlation between On.Ar and age. The strength of the correlation varies from low (clavicles) to strong (femurs) and appears to be bone specific. Sex based differences are also evident with the strongest, negative, correlation between On.Ar and age in the females of each bone group. Based on our data, a decrease in osteon size with increasing age is bone specific and appears to be most evident in females.
Estimating stature in human skeletal remains of Asian ancestry is problematic for forensic anthro... more Estimating stature in human skeletal remains of Asian ancestry is problematic for forensic anthropologists due to the paucity and uncertain suitability of regression formulae. To address this issue, our study analyzed 64 individuals from a modern skeletal collection of South-East Asian origin and developed population-specific ordinary least squares regression formulae to estimate skeletal height from each of the long bones of the upper and lower limbs, as well as from trunk length. Results indicate that the most accurate estimates of skeletal height from a single bone (as measured by standard error of the estimate—SEE) are from tibial length in males (SEE = 2.40 cm) and from humeral length in females (SEE = 2.59 cm), followed by femoral length (SEE = 2.84 cm). When multiple elements are considered, the combination of femoral and tibial length yields the best estimates in both sexes as well as combined sex samples (male SEE = 2.40 cm; female SEE = 2.77 cm; combined sex SEE = 2.54 cm).
Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in hu... more Numerous studies have reported on the age associated change in mean osteon size (On.Ar mm2) in human cortical bone. While some report a decrease in On.Ar with age, other studies have found no change. The purpose of this study was to examine the correlation between On.Ar and age in a variety of bones: metacarpals (74), clavicles (n=22), ribs (n=102), tibias (n=27) and femurs (n=38). All bone samples and data were obtained from a variety of sources; archaeological excavations, dissecting room cadavers, autopsies and forensic cases. On.Ar was quantified in the mid-shaft cortex of at least 50 osteons in each bone at 200x magnification using the point count method. Recently, a study of Euro-Canadian second metacarpals determined that there was no correlation between age and On.Ar. In this study On.Ar in a sample of Inuit second metacarpals was also found not to decrease with age (r=.10). Data from clavicles (r=.29), tibias (r=.32), ribs (r=.52), and femurs (r=.72) show a negative correlation between On.Ar and age. The strength of the correlation varies from low (clavicles) to strong (femurs) and appears to be bone specific. Sex based differences are also evident with the strongest, negative, correlation between On.Ar and age in the females of each bone group. Based on our data, a decrease in osteon size with increasing age is bone specific and appears to be most evident in females.
Skeletal histomorphometry is an important
tool for physical anthropologists
and can be used to ... more Skeletal histomorphometry is an important
tool for physical anthropologists
and can be used to estimate age and to
examine pathological conditions, activity
levels and overall health and nutrition.
In physical anthropology, measurements
most often analyze cortical bone
because of its durable nature. Although
the variables skeletal biologists examine
have been standardized, the actual
techniques used to accrue these data
from a thin section may vary. The purpose
of this research was to examine
the accuracy of newer technological
tools used to measure variables in comparison
to the standard eyepiece counting
reticule to determine whether there
was a significant variance in results
from each method. Total area (Tt.Ar.)
and cortical area (Ct.Ar.) were measured
and used to obtain a measurement
of relative cortical area (Tt.Ar/Ct.Ar.).
Three researchers with varying levels of
experience with histomorphometry compared
four methods of obtaining these
variables; one of them being the use of
a Merz1 counting reticule and three
others using the commonly used software,
ImageJ1, to measure cortical and
total area but obtaining the thin section
images in three different manners: 1)
using a flatbed scanner, 2) overlaying
multiple images of a thin section using
Photoshop1 and 3) using a digital SLR
camera with macro settings. Statistical
analyses using ANOVA indicate no significant
differences amongst observers
and the four methods examined. The
benefits and drawbacks of each method
are discussed as well as precautions one
should take while conducting histomorphometric
data collection.
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tool for physical anthropologists
and can be used to estimate age and to
examine pathological conditions, activity
levels and overall health and nutrition.
In physical anthropology, measurements
most often analyze cortical bone
because of its durable nature. Although
the variables skeletal biologists examine
have been standardized, the actual
techniques used to accrue these data
from a thin section may vary. The purpose
of this research was to examine
the accuracy of newer technological
tools used to measure variables in comparison
to the standard eyepiece counting
reticule to determine whether there
was a significant variance in results
from each method. Total area (Tt.Ar.)
and cortical area (Ct.Ar.) were measured
and used to obtain a measurement
of relative cortical area (Tt.Ar/Ct.Ar.).
Three researchers with varying levels of
experience with histomorphometry compared
four methods of obtaining these
variables; one of them being the use of
a Merz1 counting reticule and three
others using the commonly used software,
ImageJ1, to measure cortical and
total area but obtaining the thin section
images in three different manners: 1)
using a flatbed scanner, 2) overlaying
multiple images of a thin section using
Photoshop1 and 3) using a digital SLR
camera with macro settings. Statistical
analyses using ANOVA indicate no significant
differences amongst observers
and the four methods examined. The
benefits and drawbacks of each method
are discussed as well as precautions one
should take while conducting histomorphometric
data collection.
tool for physical anthropologists
and can be used to estimate age and to
examine pathological conditions, activity
levels and overall health and nutrition.
In physical anthropology, measurements
most often analyze cortical bone
because of its durable nature. Although
the variables skeletal biologists examine
have been standardized, the actual
techniques used to accrue these data
from a thin section may vary. The purpose
of this research was to examine
the accuracy of newer technological
tools used to measure variables in comparison
to the standard eyepiece counting
reticule to determine whether there
was a significant variance in results
from each method. Total area (Tt.Ar.)
and cortical area (Ct.Ar.) were measured
and used to obtain a measurement
of relative cortical area (Tt.Ar/Ct.Ar.).
Three researchers with varying levels of
experience with histomorphometry compared
four methods of obtaining these
variables; one of them being the use of
a Merz1 counting reticule and three
others using the commonly used software,
ImageJ1, to measure cortical and
total area but obtaining the thin section
images in three different manners: 1)
using a flatbed scanner, 2) overlaying
multiple images of a thin section using
Photoshop1 and 3) using a digital SLR
camera with macro settings. Statistical
analyses using ANOVA indicate no significant
differences amongst observers
and the four methods examined. The
benefits and drawbacks of each method
are discussed as well as precautions one
should take while conducting histomorphometric
data collection.