exam 2 Flashcards
1
Q
who can you estimate the sex of based on remains
A
adult male and females
2
Q
whats the most reliable element for sex estimation
A
pelvis followed by the skull
3
Q
female pelvis details
A
- greater than 90 degree angle (subpubic bone)
- sacrum is tilted back more
- Illia is spread wider
- generally bigger for childbirth
- wide sciatic notches
- ventral arc
- concave subpubic concavity
- ischiopubic ramus is pinched (if cut in half)
4
Q
male pelvis details
A
- less than 90 degree angle (subpubic bone)
- sacrum is tilted forward
- Ilia is closer together
- small sciatic notches
- convex subpubic concavity
- ischiopubic ramus would be flat/broad (if cut in half)
5
Q
metric assessment of the pelvis for sex estimation
A
- no necessary
- are difficult to obtain
- not as accurate as morphological assessment
6
Q
female skull details
A
- gracile
- sharp orbital border or supraorbital ridges are slight
- round chin
7
Q
male skull details
A
- robust
- supraorbital ridges are extreme
- large canines
- square chins
- pronounced muscle attachment sites
8
Q
metric analysis of the skull for sex estimation
A
- less accurate/necessary compared to visual examination
- requires skill in taking measurements
9
Q
other bones to estimate sex
A
- humerus head diameter
- scapula width and height
- femur head diameter
10
Q
can subadults remains be sexed
A
no
11
Q
how can you try to estimate developmental age
A
- bone length
- union of primary centers of ossification
- tooth development and eruption
- epiphyseal union
12
Q
how to estimate degenerative age
A
- pubic symphysis
- auricular surface
- sternal rib ends
- cranial suture closure
- also cortical bone remodeling or dental changes
13
Q
bone length for estimating developmental age
A
- good till about 5 years old
- use long bones (fibula, tibia, femur…)
- these lengths can be affected by nutritional status, disease (stunted growth)
14
Q
union of primary centers of ossification for estimating developmental age
A
- good till about 10 years old
- fontanel fusion = soft spots on babies heads, these bones fuse at pretty standard times across board
- structure fusion
15
Q
tooth development and eruption for estimating developmental age
A
- deciduous dentition (baby teeth)
- partially form before birth
- becomes bone by 10-11
- permanent dentition
- begins forming around birth
- fully erupted at beginning of adulthood
- teeth made of hydroxyapatite
16
Q
epiphyseal union for estimating developmental age
A
- hundreds of these in the body (where area of growth is in long bones)
- fusion times are controlled genetically
- this is useful around 10-25 years old
- the degree of fusion is used
- obliterated = can’t see fusion line anymore
17
Q
what happens after puberty to your skeleton
A
deteriorates
18
Q
microtrauma to bones
A
- to pubic bones and ribs
- tiny trauma caused by everyday life experiences to your bones
- costal cartilage - attaches rib bones to sternum
- pubic symphysis over time goes from beveled to smooth/flat
19
Q
early pubic symphysis degenerative age estimation methods
A
- Todd 1920
- Relies mainly on descriptions
- 10 stages, 5 year intervals
- Didn’t work so well
- McKern and Stewart 1957
- Divides pubic symphysis into 3 areas: dorsal, ventral, and rim
- Rarely used today
- They only looked at white males though
20
Q
later pubic symphysis degenerative age estimation methods
A
- Suchey and Brooks 1990
- Most often used today
- Cast system = Made a cast of youngest and oldest pubic symphysis of each phase groups
- divides into 6 phases of varying length
- Based on modern autopsies of a variety of people
- A morphological system
21
Q
articular surface used to determine degenerative age
A
- Articulation point between sacrum and ilium
- Survives traumatic injury well
- 5 aspects for examination
- Very subtle area of estimating age
- Texture changes
- Retro auricular surface (behind the surface)
- Apex “point of the ear”
22
Q
sternal rib ends to estimate degenerative age
A
- made by Iscan et al 1984/5
- right 4th rib used to develop technique, can apply to ribs 4-7
- less precise than os coxa methods
- features to look at = texture, contour, outer margin around the rib edge, rib contour
23
Q
cranial suture closure for estimating degenerative age
A
- technique made by Meindl and Lovejoy in 1985
- ectocranial and endocranial (inside/outside)
- where bones of skull meet
- looking at the degree of closure
- less precise than os coxa method
- complete fusion doesn’t complete till 80 years old if ever
24
Q
cortical bone remodeling for estimating degenerative age
A
- not used often
- most accurate/precise age estimation for adults
- least common because of its destructive nature for bones
- take thin section of femur at mid shaft and cut it in half
- then cut into little section and sand down to one osteon thick
- make wet mount and view on slide
- look at ratio of whole osteons (secondary) and primary osteons (first to form when growing and replaced)
25
dental attrition for estimating degenerative age
- last ditch method
- look at tooth wear
- is population/culture specific
- not seen as much in modern populations
26
dental traits to look at for estimating degenerative age
- Cementum (outer covering of tooth roots) apposition
* Count rings of cementum like rings in a tree
- Root transparency
* Root becomes more transparent with age
- Root resorption
* Roots will resorb as you get older, there is a loss of the tip of the root
- Can only give you a vague young, middle, or old grouping
27
whats anthroposcopy
- Observing visually discernible differences between groups
- This can only be done on adults
- Children haven't developed their facial skeletal structure yet
28
cranial traits to observe for ancestry estimation
- Only use the cranium for ancestral estimation
- Nose
- Face
- Vault
- Jaws and teeth
29
observing the root of the nose
- where the nasal bones meet the frontals
White - high and narrow
black - low ridged, broad
Native american/Asian traits fall in between
30
observing the bridge of the nose
- ridge of bone formed by the nasals
White - high and arched
Black - low and sloped
Native american/Asian traits fall in between
31
observing the spine of the nose
- projection at the inferior nasal border
White - very pronounced
Black - almost non existent or very tiny
Native american/Asian traits fall in between
32
observing the lower border of the nose
- the nasal sill
White - very sharp sill, almost a projection
Black - have more of a “gutter”, looks scooped out
Native american/Asian = sharp but not protruding
33
observing shape and size of the nose
White - teardrop shape, long, narrow nasal apertures
Black - short, round, wide, nasal apertures
Native american/Asian traits fall in between
34
Prognathism
- the projection of the maxilla in front of the nasal spine
- How far in front of the base of your nose does your upper jaw extend
White = “flat face”, almost no projection
Black = more projection
Native american/Asian = smaller
35
width and shape of face
White and black = very narrow faces
Native american/Asian = wide faces
*Caused by forward projection of zygomatic bones (cheek bones)
36
eye orbits
- the socket for the eye
White = have a angular shape, almost rectangle, with a downward projection
Black = more rectangular, not tilted
Native american/Asian = round appearance
37
orbital border
the ring of strengthened bone along the eye orbit
38
things to observe in the vault for ancestry estimation
- Post bregmatic depression
- Wormian bones
- Inca bone
- Suture complexity
39
post bregmatic depression
- a slight concavity posterior to Bregma
- Bregma is junction of sagittal and coronal suture of skull
- Small dip from side profile view on top of skull
40
Wormian bones
intrasuture bones (grow in sutures do to their complexity)
41
inca bone
- a separation bone found at Lambda
- Very common in descendants of Incan operations
- Caused by failure of some suture formation
42
Suture complexity
White = sutures are not as squigled
Native american/Asian = very squigled sutures
43
crowding of the teeth related to ancestry
Very common in whites because jaws are not as long (prognathism)
44
dental arch related to ancestry
- the shape of the alveolar bone (the part that holds the teeth)
White = has parabolic shape/dental arch, narrow base, high arch, posterior shape are not parallel
Native american/Asian = elliptical shape, posterior shape are not parallel, very short dental arch
Black = teeth are more parallel, almost squared off shape
45
incisor shape related to ancestry
- Spatulate shaped incisors
- Shovel shaped incisors = common native american characteristic
46
estimating ancestry without the cranium
- Very little difference between the groups
- Only slightly reliable characteristic is femoral curvature
* white/asians = more curved
* Black = straight
47
metric analysis for estimating ancestry
- use ForDisc 3.0
- Takes measurements and compares to thousands of individuals
- Is hard, have to know how to do it and get good data for good results
48
different ways to start estimating stature
- Lay the cadaver out on the table = Soft tissue shrinkage alters estimation, Shrinkage caused by dehydration to the body
- Hang the cadaver by the ears = Can increase measurements by 2 inches, Maximizes all extension of joints etc
- Lay bones on the table = All significant bones must be present, Logistical problems of disarticulated skeletons, Difficult to reproduce in vivo intrabone spacing
49
Problems with stature estimation
- Mismeasurement of the living = Interobserver error
- Stature varies with time of day = You are taller in the morning
- Secular changes = We are taller than earlier generations
- Lies = People lie when asked about height and weight
50
Fully method to estimate stature
- Rarely used
- Uses summed heights of skull, vertebra, femur, tibia, and ankle (Has an adjustment for soft tissue)
- Accurate within ½ inch
- Problems = Time consuming, Requires several elements, Only used white males in method development
51
Trotter and Gleser method for estimating stature
- Can use any of the long bones = Legs more accurate than arms, requires one long bone to make estimation, best to use is the femur
- Developed on over 5000 skeletons = inclusive study
- groups differ in body proportions = Requires knowledge of sex and ancestry, Woman tend to have longer torsos and shorter legs, and opposite for men, small differences in proportions based on racial group/culture
- Age correction = 0.06 cm per year reduction after 30 years old, Your vertebral disc soften at this age because of hormonal change
52
Regression analysis for estimating stature
- Y = mx + b
- Plot on a graph that shows correlation
- Have to know sex and ancestry in order to use correct equation to find stature
