After the general groups of race, sex, stature and age have been investigated, the bones must be examined for any idiosyncratic features that give them a personal identity. This is invariably a matter of matching up such feature(s) with known pre-existing conditions, and depends upon a potential match being available. Circumstances are infin- itely variable and the ways in which this suspected matter comes to the examiner’s knowledge are legion. Sometimes there may be one ‘good bet’ and, indeed, the potential identity may be virtually certain from the circumstances, the anatomical confirmation being almost a formality. In
Personal identity from skeletal material
TABLE3.12 Selected anthropometric dimensions (mm) in White and Black* Americans
Men Women
White Black White Black
Mean SD Mean SD Mean SD Mean SD
Body
Stature 1706 60.5 1744 60.8 1597 78.1 1586 64.9
Total arm length 760 30.2 798 41.2 695 38.1 713 32.7
Upper arm length 333 16.4 340 21.9 302 22.8 303 15.6
Forearm length 249 12.4 269 15.0 225 16.7 237 14.7
Hand length 187 9.3 199 12.3 172 11.3 179 10.2
Leg length (anterior supine) 938 40.0 984 49.1 871 51.2 892 41.8
Thigh length 497 24.3 515 27.5 461 31.6 467 24.9
Lower leg length 376 19.8 401 23.7 352 25.8 365 19.8
Foot length 244 11.9 256 13.9 215 13.6 231 11.8
Bi-iliac breadth 292 16.9 270 16.5 287 22.5 267 24.7
Bi-spinous breadth 246 17.2 227 18.1 242 25.1 220 22.5
Head
Maximum length 188 7.5 193 6.1 182 6.5 186 7.7
Maximum breadth 154 6.5 149 6.1 145 5.6 144 6.2
Auricular height 120 5.1 124 5.3 118 5.3 120 4.8
Face
Bizygomatic breadth 139 6.7 139 6.1 130 7.0 132 8.7
Mandibular breadth 110 7.4 109 8.7 103 8.9 105 11.9
Interocular breadth 33 3.5 35 2.7 31 2.8 34 2.3
Total morphological height 122 9.7 125 7.6 113 9.5 116 11.6
Upper face height 69 6.3 71 5.6 66 6.2 67 4.5
Nasal height 54 4.7 52 4.8 52 3.8 50 4.4
Nasal breadth 35 3.7 43 3.7 32 4.9 40 4.1
*From Todd and Lindala (1928). Compiled by Krogman and Iscan (1986).
TABLE3.11 General racial features in the skull (after Krogman 1939)
White (‘Caucasoid’) (excluding
Feature Alpine) Negroid Mongoloid
Height of skull High Low Medium
Length of skull Long Long Long
Breadth of skull Narrow Narrow Broad
Breadth of face Narrow Narrow Wide
Height of face High Low High
Sagittal contour Rounded Flat Arches
Nasal opening Narrow Wide Narrow
Orbital opening Angular Rectangular Rounded
Lower nasal margin Sharp Troughed Sharp
Nasal profile Straight Slanted down Straight
Palatal shape Narrow Wide Medium
other cases there may be a list of hundreds of potential cases to search through in the hope of finding a match.
Individual characteristics may be of two main types.
■ Anatomical shapes that can be matched by radiology, measurement or other means. Examples would be frontal sinus comparison, craniometry and radiological bone architecture.
■ Discrete abnormalities such as healing fractures, metal prostheses, bone disease or congenital defects. Some artefacts, such as drill holes or wire, may immediately indicate that the bone is an anatomical specimen.
Anatomical matching depends upon accurate and detailed information about the living subject who is thought to correspond with the skeleton. Such information is usually radiographic and is derived from clinical records. The examples par excellence are dental charts and radiographs obtained from the dentist of the potential match; this is discussed in Chapter 26. Where skull films are available
from ante-mortem sources, identity can be almost assured.
The lateral view of a head can be matched with similar views taken of the skull, and both obvious anatomical landmarks compared and cranial measurements taken. The matter is further discussed later in relation to radiology, but the pro- file of the pituitary fossa as well as various intracranial dia- meters can rapidly exclude a match. In fact, a cursory glance can often confirm that the two skulls are dissimilar; making a positive correlation takes more time and requires accurate orientation of the radiographs.
Frontal sinus identification
This has been extensively studied since Schuller suggested the technique in 1921, as it is particularly useful in mutilated or burnt bodies, such as those from mass disasters like air crashes. The sinuses are well protected from all but the most extreme damage and are unique in that – as first pointed out FIGURE3.19 Identification of a homicide victim, buried for almost 2 years in a garden, was achieved by matching this callus from a previous femoral fracture, with the medical notes and radiographs obtained from a hospital. The shape and size of the callus, together with the osseous spur due to muscle traction, was identical to follow-up films taken during life.
FIGURE3.20 Identification of a skeletalized body was achieved by matching this callus from a previous ulnar fracture, with the medical notes and radiographs obtained from a hospital. The shape and size of the callus, was identical to follow-up films taken during life.
by Poole in 1931 – no two persons (not even identical twins) have the same profile of these air spaces. They appear in the second year of life and increase in size for the first two decades. They are absent in about 5 per cent of persons and unilateral in another 1 per cent. For the sinuses to be used, an ante-mortem anteroposterior skull radiograph must be available, the most common source being from a previous hospital admission or examination, usually for a head injury. The cadaver skull or head must be X-rayed in exactly the same orientation and degree of enlargement, so that some superimposition technique can be employed. The ‘forehead–
nose’ position was recommended by Schuller (1943), with the tube axis positioned level with the supraorbital margins.
The scalloped upper margins of the sinuses are used for comparison, these being smaller and more numerous in the female. Asherson’s thesis of 1965 recommends using the Caldwell occipitomental plane for the radiographs, used clinically for investigation of the nasal sinuses. This is prefer- able to the Wallers occipitofrontal view and the two projec- tions are not necessarily identical in terms of sinus profile.
Asherson recommends outlining the sinus shape in black ink on the film or tracing it onto a sheet of paper. Turpin and Tisserand (1942) projected their films on to a cardboard screen and cut out a template, weighing these from both ante- and post-mortem films to determine whether they were identical. Computed tomography of the sinuses is recommended by Reichs (1993).
Other radiological methods of comparing identity include matching of hand and wrist films, matching the profile and structure of the first rib and clavicle, and the craniometric methods of Sassouni (1959) and of Voluter (1959). The methods must be sought in either the original papers or
surveys such as the textbook by Evans and Knight (1983).
However, in general, it may be said that, wherever ante- mortem X-rays are available, especially of skull, thorax, hip or shoulder, then radiological comparisons of the dead material can almost always exclude an identity and, in many circumstances, can confirm it.
Personal identity from skeletal material
FIGURE3.21 Personal identity of this almost skeletalized fire victim was established from this healed callus on the tibia, the site of a well-documented fracture several years before death.
FIGURE3.22 The facial and cranial skeleton is unique to every person. If ante-mortem radiographs can be obtained for the person likely to be the victim, matching of the frontal sinus pattern can provide absolute identification. This body, which was washed up on the beach, was eventually matched with hospital radiographs through the sinus pattern seen at the top edge of the picture.