Attribution of Hand Bones to Sex and Population Groups

Abstract

Forensic anthropologists assign sex and population group (race) to individuals on the basis of skeletal remains. While the most useful bones for these determinations are cranial and pelvic, these are not always available. The purpose of this paper is to provide models for classification using metacarpals and hand phalanges. Four samples of 40 individuals each (black and white males and females) form the dataset. Measurements include lengths and radioulnar and dorsopalmar widths of the 19 bones of each hand. The large number of total variables necessitated separate models for metacarpal and phalangeal categories; due to the considerable number of significant differences between corresponding right and left hand variables, separate models were created for right and left sides. A stepwise discriminant procedure was used to select variables, with some highly correlated (r > 0.85) variables subsequently removed. The model for left hand metacarpals has the greatest power of discrimination (89.4%); that for right hand middle phalanges, the least (71.7%). Metacarpals assign approximately 87–89%, proximal phalanges 76–79%, middle phalanges 72–79%, and distal phalanges 81–83% of individuals to their correct sex and population groups. Models exchanging variables selected from one side for corresponding variables on the other show discriminating power ranging from 72.3 to 85.6%. Thus roughly 70–90% of individuals are correctly classified by these models; more conservative “jackknife” estimates yield a success rate of approximately 67–82%. When these models are used for classification of sex alone, 89.9–94.4% (“jackknife” range, 88.7–94.4%) of cases are correctly classified; for race alone, 80.5–98.1% (“jackknife” range, 77.4–96.9%).

Sex determination from hand dimensions for forensic identification

“…However, the issue of Sex discrimination can be very complicated in cases of intersex, bodies in advanced state of putrefaction, mutilated, fragmentary and skeletonized remains in which it is common to recover dismembered & peripheral parts of the body. Forensic anthropologists routinely work with skeletonised and badly decomposed bodies, and collect osteometric data which is generally very straight-forward and stature estimation from various parameters [2][3][4][5] such as Hand outlines 6 and determination of sex 7,8 are often the easiest component for generation of the biological profile. But, the collection of osteometric data can be more challenging when dealing with fleshed remains as there is the need for soft tissue dissertation.…”

Sex determination using proximal hand phalanges

“…Concerning proximal hand phalanges, however, there are few researches investigating sex determination. Among them, some utilize multiple functions from all ten proximal hand phalanges [4,6] while others focus on specific phalanges or phalangeal dimensions [3,5,21]. Due to the fact that most functions selected vary among studies, a direct comparison was rarely possible.…”

“…Case and Ross [5] studied the ML of proximal phalanges in a sample of 259 skeletons from the Terry Collection. The discriminant equations that derived from their data provided an accuracy of 80.8% using the ML of all left proximal hand phalanges [1][2][3][4][5] and an accuracy of 83.1% using all right proximal hand phalanges [1][2][3][4][5].…”

“…Indeed, the bibliography provides a plethora of publications on the development and appliance of sex diagnostic methods using pelvic and cranial features [2]. Recently, however, there is a growing trend towards sex determination from various parts of the skeleton, including hand bones, such as proximal phalanges [3][4][5][6].…”

“…As a result, they could contribute to sex diagnosis of poorly preserved human remains. In forensic anthropology, they could assist in personal identification of decomposing or skeletonized bodies, while, in bioarchaeology, they could contribute to a more precise reconstruction of the demographic profile [4].…”