Estimation of Purkait’s triangle method and alternative models for sex assessment from the proximal femur in the Spanish population

Abstract

The current study was undertaken to test the validity and reproducibility of the Purkait triangle method and some alternative proposals for sex prediction from the proximal femur in the adult population of Spain. To that end, sexual dimorphism of the maximum femoral head diameter and the minimum femoral neck diameter were also evaluated. The study was conducted on 186 femora (109 males and 77 females) taken from the San José collection of identified individuals (Southern Spain). Discriminant function analyses (DFA) employing the jackknife procedure for cross-validations were considered. Overall, more than 94% of individuals of both sexes were correctly classified. The most dimorphic single variable from the triangle method was the intertrochanteric apex distance (BC) that reached 85.5% accuracy, falling below those obtained for the femoral head and femoral neck diameter, respectively, (89.8 and 91.9%). Combining BC with the neck diameter, the predictive ability increased to 92.5%; when femoral head diameter was added to the latter two, the classification success rate improved further up to 94.6% (94.1% after cross-validation). We conclude that the classification success rates of the Purkait's method remained considerably below any of those obtained with the models proposed in the present study which proved to be a much better and more reliable choice both as single predictors and in combination with other variables.

Sex estimation from the femur using discriminant function analysis in a Central Indian population

“…An accuracy rate ranging from 63% to 100% for the distance between the point on the femoral head and greater and lesser trochanters were reported. Djorojevic et al 46 tested the validity and reproducibility of Purkait's triangle method of the proximal femur along with some other alternative models of sex prediction in a Spanish population. The models proposed in the study gave higher predictive values than Purkait's method both as a single variable and in combination with other variables.…”

Sex assessment from the proximal femur in a Spanish population based on three-dimensional computed tomography metric analysis

“…Three models developed in our recent study on dry femora 4 were validated on the sample of 3D image data. Two out of three functions show a possible applicability in sexing skeletal remains.…”

“…The poor result that VDN exhibited for the female group could have to do with the secular changes that affected female VDN, contrary to the male one which was not notably altered by this trend, as stated previously in the studies conducted on French, Caucasians and Afro-Americans, born prior to the turn of century as well as those born after 1910, respectively [6][7][8][9][10] studies assert that the secular increases in the female neck morphology decreased the distance between the male and female distributions and consequently led to a decrease in the overall classification success accuracy rate. It is possible that our original skeletal sample 4 , tested on the clinical data, was also affected by the trend due to the fact that 39.78% of it comprised the individuals born before 1909 (see Table 3, also Ref. 10).…”

“…A review of published literature showed that the proximal femur had been largely examined to estimate the efficacy in the sex assessment. For this purpose, some researchers have identified triangle on the posterior aspect 3,4 , while others have focused on different features of the proximal epiphysis 5,6 . In the cited studies, the metric data were recorded on the modern cadaveric femora following the traditional morphometric techniques.…”

Sex estimation in a Turkish population using Purkait’s triangle: a virtual approach by 3-dimensional computed tomography (3D-CT)

“…This highly robust bone area is the weightbearing point for the upper body and is expected to be larger in males compared with the relatively lighter axial skeletal weight of females. Other authors have tested and investigated Purkait's method on Spanish, Greek, European, and African American samples to develop population-specific standards and validate the reliability of the technique [12][13][14]. Some studies have even applied a variation of the method to femoral radiographs, reporting very satisfactory results [15,16].…”