SKULL GROUP FORENSIC ANTHROPOLOGY FIELD MANUAL


The skull - Frontal view (jon)
external image skull%20front%20view.gif

Here is a diagram of the anatomical directions used...(jon)
external image 200px-Body_direction.jpg



Skull Group


The skull - Lateral view (jon)

external image lateral-view-skull.jpg
The skull - Posterior view (jon)
external image SkullPost.jpg







DENTAL INDICATORS FOR RACE IDENTIFICATION

African - the central incisors are shaped like a blade, the law size is large, and the dental arcade is hyperbolic
European- the central incisors shape is rarely shoveled, the jaw size is small, and the dental arcade is parabolic
East Asian- the central incisors are often shoveled, the jaw size is large, and the dental arcade is elliptical
(jon)


CRANIUM INDICATORS FOR RACE IDENTIFICATION

African- the cranial shape is long, the post-bregma is depressed, the suture patterns are simple, and the browridges are small
European- the cranial shape is medium, the post-bregma is straight, the suture patterns are simple, and the browridges are heavy
East Asian - the cranial shape is rounded, the post-bregma is straight, the suture patterns are complex, and the browridges are small
(jon)

NOSE INDICATORS FOR RACE IDENTIFICATION

African- the nasal apature is wide, the nasal width is wide, and the spine is small
European- the nasal apature is narrow, the nasal width is narrow, and the spine is pronounced
East Asian- the nasal apature is medium, the nasal width is medium, and the spine is small
(jon)


FACIAL INDICATORS FOR RACE IDENTIFICATION

African- the profile is projecting, the shape is narrow, the eye orbits are rectangular, the lower eye border is receding, and the external auditory meatus is round
European- the profile is straight, the shape is narrow, the eye orbits are angular, the lower eye border is receding, and the external auditory process is round
East Asian- the profile is intermediate, the shape is wide, the eye orbits are rounded, the lower eye border is medium, and the external auditory process is oval
(jon)

The above racial indicators were retrieved from class notes.



Sex Determination via the Skull




Male
Female
General size
Large
Small
Architecture
Rugged
Smooth
Supraorbital margin
Rounded
Sharp
Mastoid process
Large
Small
Occipital bone
Muscle lines and protuberance marked
Muscle lines not marked
Glabella
Bony
Flat
Gonial Angle
Squared
Wide angle
Palate
Larger, broader, tends to be U-shaped
Small, tends to be a parabola
Occipital condyles
Large
Small
Determination of sex (jon)



DETERMINATION OF SEX VIA THE PELVIS


external image pelvis2.gif



Male
Female
General size
Large
Small
Architecture
Rugged
Smooth
Supraorbital margin
Rounded
Sharp
Mastoid process
Large
Small
Occipital bone
Muscle lines and protuberance marked
Muscle lines not marked
Glabella
Bony
Flat
Gonial Angle
Squared
Wide angle
Palate
Larger, broader, tends to be U-shaped
Small, tends to be a parabola
Occipital condyles
Large
Small


BONE CLASSIFICATION

long bones
- Long bones are given their name because they are much longer than they are wide. All bones in the limbs are longbones, except the patella.
short bones- these consist of the bones in the wrist and ankle
flat bones- consist of the scapulae, sternum, ribs, and the majority of the skull
irregular bones- bones that cannot be labeled long, short, or flat, they are irregular. These bones consist of the vertebrae, hip bones, the sphenoid, and the ethnoid bones.
(jon)






external image Image267.gif

Above is the femur, an example of a long bone (jon)



external image carpels180.jpg

Above are the carpals, examples of short bones (jon)



external image 11b.gif

Above are the ribs and sternum, examples of flat bones (jon)



external image pelvic-girdle.jpg

Above is the pelvis, an example of an irregular bone (jon)



MAIN BONES OF THE UPPER BODY







external image arm%20bones.gif



THE SHOULDER

clavical- is a long bones that is also known as the collar bone. the main function of it is to support the shoulder and disperse the weight from the sternum and the trunk
scapula- is a mobile bone that the majority of the shoulder muscles are attached to. provides support for the arm and other muscles of the upper body.
(jon)


THE ARM

humerus- provides movement of the arm and helps balance
radius- articulates with the humerus, provides support of forearm with the ulna
ulna- articulates with the humerus, provides support of forearm with the radius
(jon)


THE ARM BONES AND HEIGHT IDENTIFICATION

The humerus, ulna, and radius can be used to estimate the height of an individual through different calculations. These calculations depend on ancestry and sex. The calculations are the factor x bone measurement + constant. The factor and constant change depending on on the bone being measured.
(jon)



THE HAND

phalanges- also known as your fingers, allow you to pick things up
metacarpals- help to move the phalanges
carpals- provides support and movement of the hand and forearm
(jon)

THE INNER BODY

http://www.health.com/health/static/hw/media/medical/hw/n1249.jpg
http://www.health.com/health/static/hw/media/medical/hw/n1249.jpg



ribs- protects the internal organs
sternum - holds the ribs together, also helps protect the internal organs
manubrium- upper part of the sternum where the clavicle and the first two ribs articulate from
xiphoid process- the attachment point for the diaphragm and abdominal muscles
(jon)


THE SPINE

external image spine.jpg

THE PELVIS


http://zinjanthropus.files.wordpress.com/2009/03/pelvis-454x309.jpg
http://zinjanthropus.files.wordpress.com/2009/03/pelvis-454x309.jpg


The main bones that are relevant to forensics are:

1) Illium
2) Ischium
3) Pubis
4) Pubis Symphysis

(jon)


BONES OF THE LOWER LEG


http://www.patient.co.uk/images/I77_L.JPG
http://www.patient.co.uk/images/I77_L.JPG



THE LEG BONES AND HEIGHT IDENTIFICATION

The femur, tibia, and fibula can be used to estimate the height of an individual through different calculations. These calculations depend on ancestry and sex. The calculations are the factor x bone measurement + constant. The factor and constant change depending on on the bone being measured.
(jon)


THE FOOT

http://media-2.web.britannica.com/eb-media/07/99107-004-B9666996.jpg
http://media-2.web.britannica.com/eb-media/07/99107-004-B9666996.jpg




TYPES OF TRAUMA

Fractures - when pressure is applied to the bone to cause it to break
Types of fractures-

Greenstick- the separation of the bone doesn't occur, it bends but doesn't break
Compound- when the bone penetrates the skin
Spiral- when the bone is twisted apart
Stress - a crack in the bone caused by overuse
Fatigue- occur from stress over a long period of time, occurs usually in the spine

Hematoma- where ruptured blood vessels pool over the injured area, this helps stabalize the pieces of bone injured as the blood coagulates

Callus- where a new fibrous bone that isn't as strong as compact bone, covers the injured area

Blunt Force Trauma- force applied over large area

(jon)

http://www.brad.ac.uk/acad/archsci/depart/resgrp/towton/Towton_Image3.jpg
http://www.brad.ac.uk/acad/archsci/depart/resgrp/towton/Towton_Image3.jpg


Sharp Force Trauma- can be caused by a slice or sheer

http://www.brad.ac.uk/acad/archsci/depart/resgrp/towton/Towton_Image4.jpg
http://www.brad.ac.uk/acad/archsci/depart/resgrp/towton/Towton_Image4.jpg


Projectile Trauma- usually penetrates to other side of bone, resulted from compressed pressure ex) a gun

http://anthropology.si.edu/writteninbone/images/GSWentrance_exit.jpg
http://anthropology.si.edu/writteninbone/images/GSWentrance_exit.jpg


Human vs. Non- Human Bone- a key way to determine if the bone discovered is human bone or not bone is through maturity and architecture

Maturity- Is the bone the size it should be? if not it is probably not a human bone. If it is the same size, sometimes you can tell if it's human if it has an epiphisis, because animal bones likely don't. Also, this can be seen in the pelvic bones that fuse with age.

Architectural- the size and density of bone, the presence of bones where they shouldn't be.
(jon)

Contemporary vs. Old Bones

-state of preservation- things like color changes, breakage, loss of soft tissue, texture, and hydration
-personal belongings- what is present with remains, what is relevant to the time period can determine what time they lived in
-state of interment- how they are buried. Posture and orientation
-body modification - tattoos, ear plugs, lip stretching
(jon)


Estimating Time Since Death

Decomposition and Skeletonization - time size death can be determined by looking at the phases below.

Warm Climates


  • First Day- Egg masses of insects, veins seen through the skin, body fluids present around mouth or nose
  • First Week- Maggots active on face, bones around eyes visible, skin and hair slipping from body, stench, volatile fatty acids may kill surrounding vegetation, bloating
  • First Month- Bloating subsides, maggots less, more beetles, skin dry and leathery, bones exposed
  • First Year- skeleton fully exposed

obtained from notes (jon)

Cold Climates

Picture1.png
Obtained from notes (jon)
Stage:



















Pubic Symphysis Morphology

M orphological changes of the articular surfaces of the innominate provides an excellent postcranial age indicators for adult remains. Variation in the face of the pubic symphysis, the anterior-most point of articulation between the two innominates in the pelvic girdle, is a common region analyzed for age determination. Todd (1920) outlined a 10-stage method for assessing this surface, based on a large sample of male innominates. Changes in the symphyseal surface over time proceed in a predictable pattern from a heavily contoured face, to one delimited by a rim in the mid 30s, to a surface marked by increasing porosity after 40 years. Analysis by Meindl and coworkers (1985) has shown the Todd method to be the most accurate of the pubic symphyseal methods available. It should be noted however, that a tendency to over-age individuals has been found after age 40 by some (BROOKS, 1955), while others claim under-aging of the 45+ year old individuals is problematic (Aiello and Molleson, 1993).
Below are the methods of Todd (1920) and Suchey/Brooks (in Brooks and Suchey, 1990). The diagrams of each method were adapted from Buikstra and Ubelaker (1994), the descriptions associated with each drawing taken from the original publications.


TODD METHOD:
external image todd.jpg Phase 1: Symphyseal face rugged, traversed by horizontal ridges separated by well-marked grooves, there being no distinction in size between the upper and lower ridges. None of the following structures are present: nodules fusing with the surface, a delimiting margin, or definition of extremities. (Age, 18-19)
Phase 2: Symphyseal surface still rugged. Horizontal grooves are becoming filled near their dorsal limit with new, finely textured bone. Bony nodules may be present, fusing with upper symphyseal face. Dorsal delimiting margin begins to develop. No delimitation of the extremities. Ventral bevel commences. (Age, 20-21)
Phase 3: Symphyseal face shows progressive obliteration of ridge and furrow system. Commencing formation of a dorsal platform. Bony nodules may be present. Definition of dorsal margin, with sharp lipping. Ventral bevel more pronounced. Extremities not delimited. (Age, 22-24)
Phase 4: Great increase of ventral beveled area. Corresponding diminution of ridge and furrow formation. Complete definition of dorsal margin through the formation of the dorsal platform. Commencing delimitation of lower extremity. (Age, 25-26)
Phase 5: Little change in symphyseal face and dorsal platform. Margin more clearly defined and more sharply lipped. Lower extremity better defined. Upper extremity forming with or without the intervention of a bony nodule. (Age, 27-30)
Phase 6: Increasing definition of extremities. Development and practical completion of ventral rampart. Retention of some granular appearance of symphyseal face indicating that activity has not yet ceased. Failure of ventral aspect of pubis adjacent to ventral rampart to become transformed into a compact surface. The rampart may therefore be somewhat undermined. Retention of the pectinate outline of the dorsal margin and slight ridge and furrow system. No lipping of ventral margin and no increased lipping of dorsal margin. (Age, 30-35)
Phase 7: Face and ventral aspect change from granular to fine-grained or dense bone. Slight changes in symphyseal face and marked changes in ventral aspect from diminishing activity. No formation of symphyseal rim. No ossification of tendinous and ligamentous attachments. (Age, 35-39)
Phase 8: Symphyseal face and ventral aspect of pubic bone generally smooth and inactive. Oval outline complete. Extremities clearly defined. No distinct "rim" to symphyseal face. No marked lipping of ventral or dorsal margin. Development of ossification in tendinous and ligamentous attachments, especially those of sacro-tuberous ligament and gracilis muscle. (Age, 40-45)
Phase 9: Symphyseal face presents a more or less marked rim. Dorsal margin uniformly lipped; ventral margin irregularly lipped. (Age, 45-49)
Phase 10: Ventral margin eroded at a greater or lesser extent of its length, continuing somewhat onto the symphyseal face. Rarefaction of face and irregular ossification. Disfigurement increases with age.
SUCHEY/BROOKS METHOD (female):
external image SBfemale.jpg Phase 1: Symphyseal face has a billowing surface composed of ridges and furrw which includes the pubic tubercle. The horizontal ridges are well-marked. Ventral beveling may be commening. Although ossific nodules may ocur on the uper extremity, a key featuer of this phase is the lack f delimitation for either extremity (upper or lower).
Phase 2: Symphyseal face may still shw ridge development. Lower an dupper extremities show early stages of delimitation, with or witout ossific nodules. Ventral rampart may begin formation as extension from either or both extremities.
Phase 3: Symphyseal face shows lower extremity and ventral rampart in process of completion. Fusing ossific nodules may form upper extremity and extend along ventral border. Symphyseal face may either be smooth or retain distinct ridges. Dorsal plateau is complete. No lipping of symphyseal dorsal margin or bony ligamentous outgrowths.
SUCHEY/BROOKS METHOD (male):
external image SBmale.jpg Phase 4: Symphyseal face is generally fine-grained, although remnants of ridge and furrow system may remain. Oval outline usually complete at this stage, though a hiatus may occur in upper aspect of ventral circumference. Pubic tubercle is fully separated from the symphyseal face through definintion of upper extremity. Symphyseal face may have a distinct rim. Ventrally, bony ligamentous outgrowths may occur in inferior portion of pubic bone adjacent to symphyseal face. Slight lipping may appear on dorsal border.
Phase 5: Slight depression of the face relative to a completed rim. Moderate lipping is usually found on the dorsal border with prominent ligamentious outgrowths on the ventral border. Little or no rim erosion, though breakdown possible on superior aspect of ventral border.
Phase 6: Symphyseal face shows ongoing depression as rim erodes. Ventral ligamentous attachments are marked. Pubic tubercle may appear as a separate bony knob. Face may be pitted or porous, giving an appearance of disfigurement as the ongoing proecss of erratic ossificaiton procededs. Crenelations may occur, with the shape of the face often irregular.







This is a link to a website that discusses skeletal trauma.
http://www.med-ed.virginia.edu/courses/rad/ext/


This is a link to a pdf file that covers all important imformation that we have covered in class this semester.
http://www-personal.une.edu.au/~pbrown3/skeleton.pdf





Fractures
Type
Characteristics
complete
broken all the way through
incomplete
crack; not all the way
comminuted
piece not with the bone
linear
pressure on skull, stress released by cracking; soft blunt weapon
stellate
star-shaped piece missing; hard blunt weapon
depressed
usually with stellate, piece pressed in; hard blunt object, sometimes sharp weapon
broken hyoid
if not adult, not fused; may indicate strangulation
timing
linear cracks do not cross prior cracks; indicate order of attack









external image sliding1.jpg
Using a sliding caliper, taking a measurement of nasal aperture

Formulae are used to separate Male from Female and Black from White from American Indian. All the measurements are plugged into these formulae and compared to standards for the final determination. Top



The best bet in determining the age of a sub-adult skeleton is examination of the teeth and jaw, when present. However, a comparative analysis may be made using the skull sutures and epiphyseal fusion in the young-adult skeleton. Sutures are the zigzag "seams" where the bones of the skull meet. Endocranial sutures (inside the skull) are more reliable as an aging method than is ectocranial suture analysis. Epiphyseal fusion refers to the closing of the "growth plates" at the ends of the long bones and clavicle, and iliac crest fusion. The teeth also become important later in the identification of a specific individual.


external image tootheruption.gif


external image sutures2.gif


external image ectosutures3.gif


external image sutures1.gif


external image epifusion2.gif Top