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on the posterior femoral head (
Purkait, 2005
). The lengths of each of the sides of the triangle
along with the three angles are included in the discriminant function analysis. The Purkait
method achieved accuracy of between 81% and 87%, which is no better than sex estimation
from a single measurement, such as the humeral or femoral head diameters (
Purkait, 2005
).
Brown and colleagues (2007) tested the Purkait triangle method on a population from the
U.S. (
Brown et al., 2007
). Their results were comparable to those of Purkait (85.5%); and they
achieved approximately the same accuracy using the femur head diameter alone (87%).
When they combined one of the measures with the femoral head, the accuracy of the discrim-
inant function analysis improved (90%) (
Brown et al., 2007
). They then used a threshold value
or sectioning point (also known as a demarking point) for the length between the apices of
the trochanters in conjunction with the femoral head diameter and the accuracy increased to
93.4% (
Brown et al., 2007
). A sectioning (or demarking) point is simply the average of both
the male and female mean values (
Bidmos and Asala, 2004
).
A recent study by Albanese and colleagues (2008) hoped to improve upon the Purkait
method by using an even more functional morphologic approach. These authors wanted
to try to see if the proximal femur reflected the same functional adaptations for childbirth
as the pelvis, assuming the pelvis is the best sex estimator (which is not true for metric
methods as demonstrated earlier in this chapter). They added new measurements from
the femur that were thought to reflect the sexual dimorphism that is seen in the pubic
bone. Like the Purkait method, this method also creates a triangle by measuring between
three points on the proximal femur: (1) the apex of the lesser trochanter, (2) the most lateral
point on the greater trochanter, and (3) the most superior point on the fovea capitis on the
head of the femur (see
Figure 4.4
).
FIGURE 4.4
Albanese method of sex estimation from the proximal femur.
