Injury, Pathology, & Remodeling and Perimortem Trauma Mechanisms

Pathology

study of disease

Osteoarthritis (degenerative)

(degenerative)

hip dysplasia

(congenital/ developmental)

Osteoporosis

(degenerative)

Antemortem Trauma

trauma that occurred during life

osteogenesis

healing, reactive bone

macroscopic phases of healing

inflammatory, reparative, remodeling

inflammatory

ossifying callus begins 2-10 days

reparative

woven bone: bridges fracture by about 2-3 months

remodeling

organized cortical bone replaces woven bone: takes months - years

Postmortem trauma

after death/ taphonomic

postmortem trauma characteristics

breaks are more jagged and brittle and color differentiates from surrounding bone

Perimortem trauma

at or around death

Perimortem trauma morphology

sharp edges, smooth surfaces, no color differentiation relative to surrounding surface

Young’s modulus

relationship of stress and strain and their effect on bone deformation

Elasticity

returns to shape

plasticity

permanent deformation

fracture/ break

too much load to bear

perimortem biomechanics

bone has plasticity and elasticity

postmortem biomechanics

bone lacks plasticity: fractures more easily

trauma mechanisms

blunt force, sharp force, gunshot wound

Cause of death (COD)

event leading directly to death

Manner of death (MOD)

legal distinction for how the COD occurred

Types of MOD

Natural, homicide, accidental, suicide, undetermined

types of perimortem bone fracture

complete vs incomplete

Trauma mechanism

fracture pattern can tell us the direction of the force

fracture path

follows the path of least resistance

Gunshot wounds

High velocity impacts

Entrance wound

clean, round/ oval surface

Exit wound

external beveling

beveling

“cone-shaped” defect in the bone; angle is always in the direction of the projectile

Keyhole- shaped entrance wound

combination of internal and external beveling

gsw - cranium fractures

radiating and concentric fractures

gsw - long bones

entrance wound but no exit wound

Slow velocity

Blunt and sharp force trauma

blunt force trauma characteristics

slightly jagged edges, and flaking off of bones

blunt force examples

falls (from heights), blows with blunt object, car accidents

sharp force trauma

created by tool with a point or beveled edge

alterations

straight line incision, punctures, gouges, and clefs

striations on bone

serrated blades are distinctive from non serrated blades

saws

dismemberment - sharp force trauma on bone

hacking trauma

combination of blunt and sharp force trauma (machete)

thermal alterations

burn trauma

pugilistic posture

normal burning patterns of body

burn pattern characteristic

skeletal region with less soft tissue will typically be exposed first

color changes in burn patterns

typically first to occur in heat-altered bone

unaltered bone

pale yellow

heat border

white line - altered bone tissue

charred bone

bone directly exposed to fire

gray to white

calcined - lost all organic content and moisture

cremation

body completely calcined, disintegrates to ash

ancestry estimation

methods perpetuated racism in varying fields

scientific racism/ polygenism

samuel morton

shovel-shaped incisors

native american/ northeastern asians

morphometric methods

scores features, and applies discriminant function analysis

carabelli’s cusp

european

structural violence

evidence of poverty and racialized capitalism in bone

porotic hyperostosis

iron deficiency

linear enamel hypoplasia

malnutrition especially in younger years