ARCL 228 Flashcards
What is the definition of trauma?
Injury caused to living tissue by an outside force.
Give three examples of trauma causes.
Projectiles, cutting tools, strangulation.
What is the role of a forensic anthropologist in trauma analysis?
To determine timing, cause, and sequence of trauma events.
What is the main difference between forensic anthropology and forensic pathology?
Anthropologists analyze bones, while pathologists examine soft tissue.
What are the five manners of death?
Homicide, suicide, accident, natural, unknown.
What is a simple fracture?
Bone broken into two segments.
What is a comminuted fracture?
Bone broken into multiple bone fragments.
Define an avulsion fracture.
Caused by tension pulling a piece of bone away.
What is an infractions fracture?
An incomplete fracture (common in juveniles).
What is a spiral fracture?
Caused by torsion forces (skiing accidents).
What are radiating fracture lines?
Cracks that start from the point of impact and spread outward.
What are concentric fracture lines?
Circular cracks around the point of impact.
What stops a fracture line from propagating further?
Sutures or other fracture lines.
What is unique about fracture lines in juveniles?
Their bones bend more, reducing the likelihood of clean breaks.
What force causes depressed fractures?
Compression.
What is antemortem trauma?
Trauma sustained before death, showing signs of healing.
What is perimortem trauma?
Trauma occurring around the time of death, with green bone response.
What is postmortem trauma?
Trauma occurring after death, with dry bone and no fracture lines.
What are signs of antemortem healing?
Porosity, callus formation, and rounded edges.
What are sharp edges and hinging evidence of?
Perimortem trauma.
What is projectile trauma?
Trauma caused by high-speed objects like bullets.
What are the three types of firearms?
Handguns, rifles, shotguns.
What is beveling in bullet wounds?
Funnel-like shapes indicating entry or exit wounds.
How does caliber affect wound size?
Larger calibers create larger wounds.
What is rifling?
Grooves in a firearm barrel that spin bullets for stability.
What are hollow-point bullets designed for?
To deform on impact and cause more damage.
What type of fracture lines are common with high-velocity projectiles?
Radiating and concentric lines.
What is a keyhole wound?
A wound caused by a tumbling bullet.
What is blunt force trauma?
Injury caused by a force impacting over a broad surface area.
What is a depressed fracture?
Bone pushed inward, often seen in the skull.
What is the sequence of skull deformation during blunt force trauma?
Inbending, outbending, radiating fractures, and bone wedges.
What are LeFort fractures?
Fractures in the face, such as the alveolar ridge and nasal processes.
How does bone brittleness affect blunt trauma?
Older, brittle bones are more likely to fragment.
What is sharp force trauma?
Injury caused by blades or pointed instruments.
What are the three main types of sharp force injuries?
Punctures, incisions, and chopping wounds.
What is wastage in sharp force trauma?
Loss of bone fragments due to heavy chopping.
How are striations used to analyze sharp force trauma?
Striations indicate the sharpness and type of blade.
What is forensic taphonomy?
Study of postmortem changes to the body and environment.
What are four postmortem changes caused by the environment?
Weathering, animal activity, burial, and fire.
How does fire damage change bone color?
Bones progress from yellow to white (calcination) as temperature increases.
What is trowel trauma?
Damage caused during excavation of remains.
How can animal scavenging marks be identified?
Punctures, pits, and parallel scoring marks.
What is rickets?
A condition caused by vitamin D deficiency resulting in soft bones.
What is osteosarcoma?
A bone tumor.
What is osteoarthritis?
Degeneration of joint causing pain and stiffness.
What is Paget’s disease?
A condition causing thickening of bones.
What are accessory bones?
Extra bones or ossicles that are not pathological.
What is enamel hypoplasia?
A defect in enamel development, often caused by malnutrition.
What is positive identification?
Matching skeletal or dental characteristics with antemortem records.
What is the role of frontal sinus analysis?
To use sinuses as a unique identifier.
What is a tentative identification?
Based on circumstantial evidence or associated objects.
What is shovel-shaped incisors associated with?
Asian or Indigenous ancestry.
What are cusp 7 teeth associated with?
Black ancestry.
What are the three core ethical principles in forensic anthropology?
Respect, confidentiality, honesty.
What is the Mohan guideline for expert testimony?
Necessary, relevant, and from a qualified expert.
What are the two components of a forensic anthropologist’s final report?
A one-page summary and a detailed discussion of results.
Why is maintaining a chain of custody important?
To ensure evidence is not tampered with or lost.
What is the difference between evidence and opinion in forensic anthropology?
Evidence is based on physical remains, while opinion is the interpretation.
What is the difference between an entry and an exit wound?
Entry wounds - smaller and beveled inward
Exit wounds - larger and beveled outward
What factors influence the size of a bullet wound?
Caliber of the bullet, bone thickness, bullet type (e.g., soft tip or hollow-point).
What does the alignment of entry and exit wounds help determine?
The direction of fire.
What are concentric fracture lines in projectile trauma caused by?
Pressure inside the skull from high-velocity bullets.
How does projectile velocity affect fracture patterns?
Higher velocity causes more extensive radiating and concentric fracture lines.
What does a non-circular bullet wound suggest?
The bullet tumbled or hit the bone at an angle.
What type of firearm typically produces multiple projectiles?
Shotguns.
What is the most common blunt force injury in the forearm called?
Parry fracture.
How can concentric fracture lines form in blunt force trauma?
When wedges of bone are forced inward due to compression.
What distinguishes blunt force trauma from sharp force trauma?
Blunt force trauma - wide area
Sharp force trauma - narrow focus
What does the presence of wedge-shaped bone fragments indicate?
Blunt force trauma.
What is the significance of skull buttressing areas in blunt trauma?
These areas (e.g., alveolar ridge) resist fractures due to their density.
What age-related factor affects skull fractures in blunt trauma?
Older skulls are more brittle and prone to depressed fractures.
What are horizontal striations in sharp force trauma associated with?
Incisions.
What are vertical striations in sharp force trauma associated with?
Punctures or chopping wounds.
What does the depth of a sharp force injury depend on?
The force applied and the type of instrument used.
How do chopping wounds differ from incisions?
Chopping wounds are deeper and can result in wastage.
What is the role of striae in identifying the weapon used?
Striae provide details about the blade’s sharpness and angle.
Why are fracture lines rare in incisions?
Force is concentrated in a small area.
What kind of marks do carnivores typically leave on bones?
Punctures, scoring, and furrows.
What kind of postmortem changes are caused by acidic soils?
Bone erosion and shadowy discoloration.
How can trowel trauma be distinguished from perimortem injuries?
Sharp, clean edges, no fracture lines.
What is kerf in the context of saw marks?
The cut made by a saw blade.
What is a false start kerf?
A shallow cut made when the saw initially fails to penetrate deeply.
What kind of saw creates smooth, polished kerf walls?
Power saws.
What are the characteristics of a crosscut saw?
Teeth are angled at 70 degrees to cut across the grain.
What are the characteristics of a rip saw?
Teeth are angled at 90 degrees to chisel material out.
How does kerf width relate to blade type?
Coarse saws - wider kerfs
Fine saws - narrower kerfs
What is the difference between superficial false starts and proper cuts?
False starts are shallow scratches, while proper cuts penetrate the bone.
What is the sequence of animal scavenging activity?
Soft tissues of the head and neck
Thorax
Upper limbs
Lower limbs
Long bones
How can rodent gnawing marks be distinguished from carnivore marks?
Rodent marks - narrower and parallel
Carnivore marks - punctures and furrows
What are furrows in animal scavenging?
Deep marks caused by carnivore teeth at the ends of bones.
Why are bones scattered during animal scavenging?
Carnivores move bones to access marrow and other soft tissues.
How do human dismemberment patterns differ from animal scavenging patterns?
Humans tend to leave head in the joints, while animals chew and scatter bones.
What is spina bifida?
Vertebral arches fail to close completely.
What is a sternal foramen?
A hole in the sternum that can be mistaken for a gunshot wound.
What is cleft palate?
A defect where the maxilla fails to fuse properly.
What is scurvy?
A condition caused by vitamin C deficiency, leading to weakened blood vessels.
What are pulp stones, and what age group are they common in?
Calcifications in dental pulp, common in individuals over 50 years old.
What is fluorosis?
Excessive fluoride intake causing hardened, fracture-prone bones.
What is ankylosing spondylitis?
Spinal bones fuse, leading to stiffness.
What is multiple myeloma?
A cancer causing weakening bones from the inside out.
What is osteonecrosis?
Bone death due to a lack of blood supply.
What is the most common form of bone cancer?
Osteosarcoma.
What is the purpose of forensic odontology?
To identify individuals and analyze injuries related to teeth.
What is the most common dental pattern in individuals?
All teeth present with no restorations.
What is enamel hypoplasia an indicator of?
Periods of malnutrition or psychological trauma.
What are the three types of opinions in forensic anthropology?
Speculation, possible, probable.
Why should definitive numbers be avoided in forensic reports?
To account for uncertainty
Why is respecting human remains important in forensic anthropology?
To uphold ethical standards and honor the deceased and their families.
What is the role of honesty in forensic testimony?
To ensure findings are data-supported and free from bias.
What is the goal of facial reconstruction in forensic anthropology?
To create a representation of an individual’s face for identification purposes.
What are the three main methods of facial reconstruction?
Anatomical (Russian), Tissue Depth (American), and Manchester (a combination of the two).
Who developed the anatomical method of facial reconstruction?
Mikhail Gerasimov.
What is the anatomical (Russian) method based on?
Reconstructing muscles, glands, and fatty tissue using skull markings.
What are the advantages of the anatomical method?
It results in very realistic representations.
What are the limitations of the anatomical method?
It is time-consuming and requires extensive knowledge of soft tissue anatomy.
What is the tissue depth (American) method?
It uses average tissue depths to reconstruct the face.
What are tissue depth markers?
Pegs placed on the skull to represent the thickness of soft tissue at various points.
What are the advantages of the tissue depth method?
It is quicker and doesn’t require as much anatomical knowledge.
What are the disadvantages of the tissue depth method?
It can produce generic-looking faces and may not account for mixed ancestry.
What is the Manchester method?
A combination of the anatomical and tissue depth methods.
What is a key advantage of the Manchester method?
It combines realism with efficiency.
How is nose length estimated in facial reconstruction?
It is based on the length of the nasal spine.
Why is facial asymmetry considered in reconstruction?
Because human faces are rarely perfectly symmetrical.
What skeletal factors influence body weight estimation?
Sex, skeletal robusticity, and height.
How does muscle mass affect body weight?
Muscle weighs more than fat and increases body weight.
What is the method for estimating body weight in forensic anthropology?
Determine sex and height, consult height/weight charts, and adjust for skeletal robusticity.
Why is skeletal robusticity important in weight estimation?
Thicker bones indicate a more muscular build, suggesting a higher weight.
What additional evidence can aid in estimating body weight?
Clothing
What is the postmortem interval (PMI)?
The time elapsed since an individual’s death.
Why is estimating PMI important?
It helps determine the timeline of death and decomposition.
What are three environmental factors that affect PMI?
Temperature, humidity, and burial environment.
What role does forensic taphonomy play in PMI estimation?
It studies how environmental factors alter remains over time.
How does burial depth affect PMI?
Deeper burials slow decomposition due to reduced exposure to environmental factors.
What are the color changes associated with fire damage to bones?
Yellowish-brown → black → gray → white (calcination).
What causes bone shrinkage during fire exposure?
Loss of organic material due to heat.
What is calcination?
The final stage of bone burning, where only calcium remains.
How does fire damage affect bone shape?
Bones can warp or twist due to heat.
What forensic evidence can fire-damaged bones provide?
Evidence of burning patterns, sequence of burning, and fuel used.
What are non-fusion anomalies?
Conditions where bones fail to fuse properly, such as spina bifida.
What is a metopic suture?
A suture in the frontal bone that may persist into adulthood.
What is a bipartite patella?
A kneecap in two parts, often mistaken for a fracture.
What are ossicles?
Extra bones found in sutures or long bones.
What is pseudarthrosis?
The formation of a false joint when a fracture fails to heal.
What is forensic radiography used for?
To compare antemortem and postmortem imaging for identification.
What is unique about frontal sinus morphology?
It is as unique as a fingerprint and can aid in identification.
What are three features analyzed in frontal sinus comparison?
Size, symmetry, and scalloping.
What is a common issue with using frontal sinus radiographs?
Not everyone has them, and x-rays must be taken at the same angle for comparison.
What are trabecular patterns, and how are they used?
Unique patterns in long bones used for identification.
What are the three types of strangulation?
Hanging, ligature, and manual strangulation.
Which type of strangulation is most likely to fracture the hyoid bone?
Manual strangulation.
What percentage of hyoid fractures occur in manual strangulation?
34%.
Why is the age of the victim important in hyoid fracture analysis?
The hyoid fuses with age, making fractures more likely in adults.
What is a key sign of ligature strangulation?
Cord impressions around the neck.
What are the two main parts of a forensic anthropologist’s final report?
A one-page summary and a detailed discussion of findings.
What is included in the skeletal analysis summary?
Case number, ancestry, sex, age, stature, trauma, and unique skeletal characteristics.
Why are appendices included in forensic reports?
To provide supporting evidence like photographs and data tables.
What is the purpose of a chain of custody?
To maintain the integrity of evidence.
What should a forensic report exude?
Professionalism, accuracy, and thoroughness.
What are the five phases of courtroom testimony for a forensic anthropologist?
Pre-trial meeting, qualification establishment, direct examination, cross-examination, redirect examination.
What are ‘Mohan guidelines’?
Standards for admissibility of expert testimony in Canadian courts.
What must expert testimony be based on?
Evidence that is tested, peer-reviewed, and accepted by experts.
What is the difference between direct and cross-examination?
Direct examination involves presenting evidence, while cross-examination involves answering opposing counsel’s questions.
Why is it important to avoid overstating certainty in testimony?
To maintain credibility and ethical standards.
What is the purpose of bite mark analysis?
To link a suspect to an injury or piece of evidence.
What is osteochondritis dissecans?
A condition where bone tissue dies due to lack of blood supply.
What is a kerf wall?
The interior surface of a saw cut.
What does beveled bone indicate?
A gunshot wound, with inward or outward beveling.
What is a philtrum in facial reconstruction?
The groove between the nose and upper lip.
What is an overbite, and why is it significant?
A dental condition affecting facial reconstruction and bite analysis.
What is bruxism?
Tooth grinding, often mistaken for wear due to age or diet.
What does a shallow vs. deep puncture indicate in sharp force trauma?
The depth depends on the force applied and the object used.
What is hypertrophic osteoarthropathy?
A condition causing swollen joints and bone deposition due to lack of oxygen.
What is neurofibromatosis?
A genetic condition asymmetrical bone growth.
What is the primary difference between static and dynamic forces?
Dynamic forces are sudden, while static forces build slowly.
What is a concentric fracture line?
A fracture that creates rings around the point of impact.
What is fluorosis?
Excessive fluoride intake leading to brittle bones.
What are osteoblasts?
Cells responsible for bone formation.
What are osteoclasts?
Cells that break down bone tissue.
What is a temporalis muscle in facial reconstruction?
A muscle critical for chewing and head shape reconstruction.
What is gout?
An inflammatory arthritis caused by uric acid buildup.
What is ankylosing spondylitis?
Fusion of the spine, leading to stiffness.
What is the difference between a transverse and a spiral fracture?
A transverse fracture is straight across; a spiral fracture is caused by twisting.
What is meant by ‘speculation’ in forensic anthropology opinions?
A guess with little to no data support.
What is a ‘probable’ opinion in forensic anthropology?
A conclusion with the highest level of certainty possible.
Why are bullet exit wounds often larger than entry wounds?
Due to deformation of the bullet and greater outward pressure.
What is a ‘green bone response’?
A reaction of living bone to perimortem trauma, indicating flexibility and moisture.
What is beveled bone in projectile trauma?
Funnel-shaped bone damage at entry and exit points.
What does thermal shrinkage indicate in bones?
Exposure to high temperatures leading to reduced bone size.
What is a LeFort I fracture?
A horizontal fracture separating the maxilla from the skull base.
What are accessory foramina?
Small holes in bones, often mistaken for trauma.
What is spondylolysis?
A condition where the vertebral arch fails to fuse with the body.
What is the primary cause of concentric fracture lines in blunt trauma?
Inward pressure from impact compressing the bone.
What are hinge fractures, and what do they indicate about bone moisture?
Incomplete fractures indicating perimortem trauma, as the bone bends rather than breaking cleanly.
How do concentric fracture lines differ in projectile vs. blunt force trauma?
Projectile trauma -pressure-induced concentric fractures Blunt trauma - surface-level concentric fractures.
What are the limitations of forensic radiography for identification?
Lack of antemortem records, difficulty replicating x-ray angles, and radiation avoidance in living individuals.
What does twisting in fire-damaged bones suggest about burn intensity?
High-intensity burns cause shrinkage and warping due to collagen loss.
What type of bone erosion is caused by acidic soil?
Gradual degradation and pitting, often leading to loss of cortical bone layers.
What is Callie’s fracture, and how does it occur?
A specific type of wrist fracture caused by falling onto an outstretched hand, often resulting from shearing forces.
How does bending trauma typically occur?
It happens when force is applied perpendicular to the long axis of a bone, often causing parry fractures in defensive injuries.
Why are torsion fractures more common in accidents like skiing?
Torsion fractures occur when one end of the bone is stationary and the other twists, as in feet stuck in ski boots during a fall.
What is a ricochet wound, and how is it identified?
A wound caused by a bullet that has bounced off another surface, often smaller and irregular in shape.
How can radiating fracture lines help determine the sequence of bullet wounds?
Fracture lines from a subsequent bullet will stop at those caused by an earlier shot, revealing the order of impacts.
What is the significance of projectile focus in trauma analysis?
Focus refers to the area of impact: narrow focus (e.g., bullets) causes concentrated damage, while wide focus (e.g., shotgun pellets) affects a broader area.
What is kerf progression, and how is it analyzed?
The direction of saw movement during a cut, identifiable by the entrance being well-defined and the exit rougher.
How can the blade width be estimated from kerf marks?
Kerf width is divided by 1.5 to approximate the blade width.
What distinguishes a power saw kerf from a hand saw kerf?
Power saw kerfs have smoother, polished walls, while hand saw kerfs show irregular striae due to manual cutting.
What is the tooth set in saw analysis, and why is it significant?
The offset of saw teeth, creating a kerf slightly wider than the blade, which indicates the type of saw used.
How does fire damage cause twisting or warping in bones?
Heat causes uneven contraction of organic material, leading to deformation.
What environmental conditions exacerbate bone flaking?
Prolonged exposure to sunlight or alternating wet and dry cycles.
How does acidic soil affect buried bones?
It erodes the cortical bone, leaving a shadowy or porous surface appearance.
How is ear size estimated in facial reconstruction?
Ear length is estimated as the same length as the nose, and the width is half the length.
What factors influence the shape of the lips in reconstruction?
The shape and size of the teeth, along with bite patterns (e.g., overbite, underbite).
What is the role of the nasal spine in estimating nose length?
The length of the nasal spine is multiplied by three to approximate the length of the nose.
What is the most challenging aspect of facial reconstruction?
Determining the thickness of soft tissue at specific cranial landmarks due to variation in ancestry, age, and body type.
What is a frontal sinus scalloping pattern, and why is it significant?
The scalloped edges of the frontal sinus vary uniquely between individuals, aiding in identification.
What challenges arise in comparing antemortem and postmortem x-rays?
Differences in imaging angles, equipment, and resolution may complicate comparisons.
What parts of the skeleton are commonly analyzed in radiography besides sinuses?
Cranial sutures, dental patterns, and long bone trabecular structures.
How can healed fractures aid in radiographic identification?
They create unique patterns visible in both antemortem and postmortem x-rays.
What distinguishes hanging from ligature strangulation in terms of neck markings?
Hanging typically leaves a V-shaped mark, while ligature marks are horizontal.
What is the physiological cause of death in most strangulation cases?
Asphyxia, caused by compression of the airway and blood vessels.
What is the significance of time to death in strangulation cases?
Manual strangulation takes 3-4 minutes to cause death, while ligature times vary based on pressure applied.
What is Diffuse Idiopathic Skeletal Hyperostosis (DISH)?
A condition causing ossification of ligaments, especially along the spine.
What is myositis ossificans?
A condition where muscle tissue turns into bone after trauma.
How can tool marks on bone help identify a perpetrator?
By linking specific saw or knife marks to a tool type or brand.
What does periostitis indicate about antemortem health?
It shows inflammation, often linked to infection or repetitive trauma.
What is the significance of beveled kerfs in saw analysis?
They indicate the type and direction of the saw blade’s movement.
