2. As humans, we have three basic
social groups. These groups are
Caucasoid, Mongoloid, and Negroid.
With the addition of inter-breeding,
many other subgroups can be found.
Each group possesses unique
skeletal characteristics which allow
us to "race" the remains of person. In
addition to race, we can also
estimate age, stature, and sex.
3. It consists of a five phase procedure:
• A general description and confirmation of the human
origins of the material.
2) The estimation and segregation of the minimum
number of individuals.
3) The determination of sex.
4) The estimation of age.
5) The estimation of stature.
Using Bones for Identification
4. The human skeleton consists of both fused
and individual bone. Fused bones include
those of the pelvis and the cranium.
At birth a newborn baby has approximately
300 bones, whereas on average an adult
human has 206 bones . The difference comes
from a number of small bones that fuse
together during growth, such as the sacrum
and coccyx of the vertebral column.
Introduction
Skeleton is an excellent material in living and non-
living population for genetic, anthropological,
odontologic and forensic investigations. Skull and
bone features vary from male to female and
differentiation is usually based on the male
features that are typically more pronounced and
marked than female features.
5. Krongman ranks accuracy of sex
determination using the pelvis at
95% , the skull at 90%, the pelvis
and skull at 98% and long bones at
80%.
The determination of sex by
examination of the skeleton is
based upon the appearances
of:
1. Pelvis (innominates +
sacrum )
2. Skull (cranium + mandible )
3. Long bones (Humerus ,
Femur )
4. Sternum
5. Scapula , metacarpal bones
6. SEXUAL DIMORPHISM
Differences between men and women
include all the features related to
reproductive role, notably the endocrine
(hormonal) systems and their physical,
psychological and behavioral effects.
7. SEXUAL DIMORPHISM –
BASIC PRINCIPLES
The evaluation of sexual dimorphism in skeleton
is generally based on two factors:
1. Size difference
2. Function related differences.
8. Determination of sex is based on two methodological
approaches:
•Morphological (based on Shape ) Adult males
and females differ in both general size and
shape, and this variation is reflected in the
skeletal anatomy.
2. Osteometric (based on bone dimensions)
Males longer or larger than females.
9. The skull is a bony structure
which serves as the general
framework for the head. The
skull supports the structures
of the face and protects the
head against injury.
The skull can be
subdivided into two parts:
the cranium and the
mandible.
10.
11.
12. SKULL
The features that indicate sex are :
• General appearance
• Supra orbital ridges
• Orbits
• Glabella
• Zygomatic arches
• Mastoid processes
• External occipital protuberance
• Mandible
• Palate
13. MALE FEMALE
When compared, the female skull
appears smaller and more gracile. The
male skull is usually larger and more
rugged.
14. This is the region directly above
the orbit and nose, or the "brow
ridge“.
Less pronounced=female
More pronounced=male
Supraorbital ridges
18. Zygomatic arches
In females, the zygomatic arch is less pronounced, and tends
to not extend posteriorly beyond the external auditory meatus.
In males, the zygomatic arch is more pronounced or
robust, and tends to extend posteriorly beyond the external
auditory meatus.
19.
20. MASTOID PROCESSES
The mastoid processes are located on the inferior
portion of the temporal bone, just posterior to the
external auditory meatus.
23. The mandible together with the maxilla, the
largest and strongest bone of the face . It
forms the lower jaw and holds the lower teeth
in place.
24. The male mandible
tends to have a
“square” shape.
Mandible of female
tends to have a
pointed chin.
Chin (anterior mandible)
25. Mandible in the
male is closer to a
right angle than
the female. In the
female, the ramus
is an obtuse
angle to the lower
jaw bone, i.e.,
greater than 90
degrees. The
ramus in the male
is wider and
larger.
RAMUS (rear of the mandible)
MALE FEMALE
28. The hip bone (or innominate bone) is a large,
flattened, irregularly shaped bone.
Together with the sacrum and coccyx, it
comprises the pelvis.
Components
It consists of three parts, the ilium, ischium,
and pubis, which are distinct from each other
in the young subject, but are fused in the adult.
Theb
e
s
tind
ic
a
to
ro
f s
e
xo
nthe
a
d
ults
ke
le
to
nisthes
ha
p
eo
f
thep
ub
icb
o
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f thep
e
lvis
.
HIP BONE
29. Sex Determination from Pelvic Morphology
The pelvic girdle is the most sexually dimorphic
region of the skeleton, and it can be used to
determine sex with a high degree of accuracy.
The sexual dimorphism of the pelvis is primarily
the result of reproductive mechanics, and is not
readily apparent until adolescence.
30. Sex differentiation in the human pelvis
1. Overall appearance between the two pelvic regions .The male pelvis is
larger and more robust than the female pelvis.
2. The size of the opening between the hips (A). The female skeleton
requires this additional room for birthing.
3. The hips in the male (B) are more vertical than the female's.
•At the rear of the pelvis is the coccyx (C), the male coccyx is larger than the
female's.
•The angle at the front of hips (D), where both sides join (pubic symphysis) is
an obtuse angle in the female, and closer to 90 degrees in the male. The
female obtuse angle is in-line with the broader birthing canal.
31.
32. Five features in innominate that indicate sex in
pubic region are:
(1) width of sciatic notch (inferior ilium)
(2) subpubic angle (concavity)
(3) ventral arc (on the pubis, near the
symphysis, ventral)
(4) ischio-pubic ramus (bone connecting
pubis and ischium)
PELVIS
(5) acetabulum diameter
(lateral innominate)
36. The subpubic angle is much wider in females than in
males, typically more that 90 degrees and less than 90
degrees, respectively.
LESS AND “V” SHAPED WIDE AND TEND TO “U”
SHAPED
SUB-
PUBIC
ANGLE
MALE FEMALE
37.
38. It is the curved ridge of bone on anterior surface of
the pubic bone.
It is common in females and almost never seen in
males.
39.
40.
41. The space in the middle of the pelvic bone (the
pelvic inlet) is larger in women to facilitate
birthing.
The pelvic inlet
is the space
you see when
both
innominates
and sacrum are
articulated.
PELVIC INLET
42. The sacrum is a large, triangular bone at
the base of the spine and at the upper and
back part of the pelvic cavity.
The sacrum articulates with four bones:
•the last lumbar vertebra above
•the coccyx below
•the hip bone on either side
43. Sexual dimorphism
The sacrum is
noticeably
sexually dimorphic .
In the female the
sacrum is shorter and
wider than in the male.
The bone is also
directed more obliquely
backward; this
increases the size of the
pelvic cavity.
Straighter in males &
curved in females.
MALE FEMALE
44. The sternum is an
elongated, flattened bone,
forming the middle portion
of the anterior wall of the
thorax. Its upper end
supports the clavicles and
its margins articulate with
the cartilages of the first
seven pairs of ribs.
It consists of three parts,
from above downward:
•Manubrium
•Body of sternum
•Xiphoid process
45. <125 mm = female
>155 mm = male
These figures are from Bass
46. • The Essentials of Forensic Medicine
By : Cyril John Polson , D.J.Gee , Bernard Knight
• Encyclopedia of Forensic Sciences
• Clinical Anatomy for Medical Students
By : Richard S . Snell
• Wikipedia
• Personal Identification from skeleton or its remains
By : G.S. Kaler & N.A. Butt
