Methods for improving the efficiency of estimating total osteon density in the human anterior mid-diaphyseal femur.
In order to preserve whole bone integrity and minimize destruction, paleohistologists often rely on histomorphometric data obtained from small areas (1.5-50 mm2) sampled within the anterior mid-diaphyseal femur. Because bone exhibits significant histological variation, the validity of results based on such sampling is questionable. The accuracy of various subareas (columns, rows, squares approximating dimensions and locations assessed by paleohistologists) in predicting total osteon density in the anterior mid-diaphyseal femur is assessed in the present study. Thirty-five specimens (12.7 mm wide, 100 microm thick, average area 56.7 mm2) were chosen at random from a skeletal population of 94 Inuits and Pueblo agriculturists. The specimens were photographed and enlarged; an acetate grid (12 columns, 10 rows, 120 squares, square = 1 mm2 of bone surface) was superimposed over the photograph; and secondary osteons and fragments were identified. Alternate columns (50% total area, T.Ar) predicted over 98% of entire section total osteon density. Two column combinations (15% T.Ar), separated by at least one column, predicted 91 to 95% of total osteon density. Individual column (8% T.Ar) predictability ranged from 48 to 86%. Two row combination (32 to 40% T.Ar) predictability values ranged from 86 to 95%. Individual rows (<1 to 20% T.Ar) predicted from 45 to 92% of total variation. Combinations of squares approximating areas and locations assessed by other paleohistologists ranged in predictability values from 80 to 94%. The results demonstrate that subareas of as little as 15% predict 95% of variation in total osteon density in the entire anterior mid-diaphyseal femoral section. A minimization of histological area evaluated without the loss of accuracy allows for a minimization of time invested in data collection and the utilization of partially damaged specimens.
Iwaniec
U T
UT
Department of Anthropology, University of Wisconsin-Madison, 53706, USA. iwaniec@creighton.edu
Crenshaw
T D
TD
Schoeninger
M J
MJ
Stout
S D
SD
Ericksen
M F
MF
D000293:Adolescent; D000328:Adult; D015519:Bone Density; D016723:Bone Remodeling; D018483:Diaphyses / Q000033:anatomy & histology*; D005269:Femur / Q000033:anatomy & histology*; D006253:Haversian System / Q000033:anatomy & histology*; D006801:Humans; D007198:Indians, North American; D004930:Inuit; D008875:Middle Aged; D010163:Paleontology / Q000379:methods*