Saturday, September 2, 2017

Forensic Notes

Skeletal Analysis: Initial treatment and examination of skeleton; sexing the skeleton and stature. Initial treatment: Reconstruction: pieces go back to original location. Example: Facial skull reconstruction Determining commingling and MN'': Minimum number of individuals Determining MN'': 1 . Duplication: no 2 bones of same type and side are present. 2. Consistency in size: ensuring that bones within individuals are same proportions Definitions Anthropometry: Measuring both living and dead Osteometry: Measurement of skeleton and its parts Anatomical landmarks of skull: Precise points in the skeleton that are used for easurements.

Example: Femur Measuring Tools Sliding Calipers: Simple measurements referencing points that are close together and when the contours of skull don interfere. Spreading Caliper: Measurements dealing with cranial vault points on skull that can''t be taken in a straight line. Osteometric Board: Measures long/large bones. Tape Measure: Measure circumferences of long bone shafts. Fordisc 3. 0 Computer program utilizing discriminant functions based on modern populations 24 cranial, 10 mandibular, 44 postcranial measurements. Sex, ancestry and stature

Program developed at University of Tennessee Only tarsal that is measured is the calcaneus Forensic Report Always a quick summary. Narrative is the analyzation of remains found (Agency) Biological profile contains 5 categories 1. Age 2. sex 3. Stature 4. Anomalies 5. Individualizing traits (fragment bones, tumors, metopic suture, dental markings) Trauma 1 . Ante mortem: (before death) 2. Perimortem: (At or time around death) 3. Post mortem: (Atter death) Ante mortem has evidence of healing bones Perimortem has no signs of healing bones/flesh because of the environment

Time since death (sometimes) anthropologist doesn''t apply. Very rare if the anthropologist gives time of death Identification (if asked) depending on what is provided Anthropologist cant ID without ME approval yet can provide notes and report (Pathologist or MW would need to provide additional information) Murder case needs positive ID''s (DNA) Regardless how it''s done the forensic report must be thorough Weight and Body Build Nothing is usually mentioned about weight Body build, muscle attachments gets larger Determining sex of skeleton Assessment based on: Reference sample # of bones available

Entire skeleton: 90-100% pelvis: 90-95% Skull: 80-90% Long Bones: 80% Range overlaps between males and females. Want to utilize as many traits possible for determing sex. Females = Gracile Males = Robust We only determine biological sex and not gender! Hermaphrodite Caster Semenya 18 yr old from rural S. Africa village Big muscular, flat chested, deep voice... Rapid improvements of times set in Long run 2009 world Championships Gold Medal in 800 meter run Questions that people asked: If she was on drugs (steroids), etc. International Association of Athletics Federations (IAAF)

Leaked the information determining that Semenya was a hermaphrodite and that male organs weren''t visible. They allowed her to keep medal and prize money If somebody would be hermaphrodite skeletal features would be more robust (male type skeletal) Sexing Sub adults Sex ditterences do not snow until atter pube Difficult to sex kids Sexing starts with teenagers Ultimately to determine sex we would use DNA Postcranial Sexual Dimorphism One sex larger than the other Overall size and robusticity Robust, Gracile Example: Femoral and humorous to determine sex Single Measurment

Vertical diameter of the femoral head to determine sex Female 47mm Only used when fragmentary skeletal remains Pelvic inlet shape Females-wide and flaring iliac bones Pelvic inlet (brim) Females-wider and oval from side to side Male-Narrow heart shape Subpubic Angle/Sacrum Subpubic angle Males-less than 90 degrees (v shape) Females-greater than 90 degrees (u shape) Sacrum Males-langer narrower and curved Females-wider, shorter, flatter Greater sciatic notch Narrow in males Wide in females-approaches 90 degrees A lot of overlap (narrow in male, really wide in females) Phenice technique (Pubic Bone)

Phentce (1969) Most reliable non-metric technique of pelvis Morphology of the pubic bone Ventral Arc Sub pubic concavity Ischio pubic ramus Pubic single most important part of skeleton for adult biological profile Females-slightly elevated ridge of bone across the ventral surface. Subpubic concavity Females-concave surface aspect of ischio pubic ramus In females-ridge on medial aspect of ischiopubic ramus Pubis/ Acetabelum Pubis Shape: Females-rectangular and or longer Males-triangular and or shorter Auricular Area Joint surface for the sacrum Auricular surface: Females-raised

Males- Flatter Pre-auricular sulcus (groove between auricular and greater sciatic notch) Occurs more frequently in females and if present in males poorly developed, pubic bone for childbirth Dorsal Pubic Pits Very pronounced pits-females (perhaps indicator of birth) Skull Males (robust, rugged) Expression of robust traits varies in populations Example: Asians are smaller than European, so European females could be mistaken for Asian male base. Ancestry should be assessed first Female Cranial Traits- Gracile Small, smooth cranium Small, non projecting mastoid Smooth browridges

Frontal high rounded (parietal bossing) Smooth nuchal area-neck muscle attachment Sharp supraorbital margin Narrow Zygomatic arch Male Cranial Traits- Robust Large rugged cranium Pronounced muscle insertion such as temporal lines Large, projecting mastoid Large, browridge inflated Slanting frontal Rugged supraorbital margin Broad zygomatic arch that extends pas External Auditory Meautus Broad and square chin (U), wide ascending ramus and gonial flaring rounded chin (V) with narrow ascending ramus Males-larger gonial area Additional bone after straight line (positioned gonial bone extra)

Masculinization Older female skeletons more robust (over time/years/age) Stature Methods Thomas Dwight: Father of forensic anthropology and first to study stature. Essentially added clay in between skeletal Joints (very messy and disruption of skeletal remains) Direct measurement of re-articulated skeleton Basic approach: Measure bones from skeletons of persons whose stature in life was known. Uses data to develop tables or formulas Today we would use foredisc Problems with estimating stature Varies during the day Loss of stature with increasing age

Considerable variation within a population Bias between reported height (license) and measured height Example: Men overestimated height, females underestimated their height When stature is reported mean and range should be also reported that range is +1- 6-7inches. Case Study Juvenile: Teeth Adults: Joints Fetus, children: Long bones (measuring the diaphyseal length of femora) Aging Maximum diaphyseal length of the femora Left: 74. 3mm Right: 74. 2mm Case studies for fetal aging, term baby are the diaphyseal length of femora Usually term babies are part of homicide or death while birthing

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