Forensic Pathology Flashcards
(47 cards)
cause of death
disease or injury that initiated the lethal chain of events
o May precede death by seconds or years
o Intermediate illnesses of conditions may connect current fatal condition to initiating condition
o Can stand alone on death certificate
Not: cardiac arrest, respiratory arrest, renal failure, asystole, etc
mechanism of death
nonspecific etiology; broad differential; cannot stand alone on a death certificate
o Cardiac arrest, hypoxia, etc
manner of death
how/circumstances – natural, accident, suicide, homicide, undetermined
rigor mortis
-lactic acid builds up while cells try to stay alive –> this stiffens the muscles
marbling
decomposition that occurs initially in the vasculature
abrasion
scraping and removal of superficial skin; contact with rough surface, by sliding or pressure
o Scrape (linear), Brush burn/Road Rash (frictional force of rubbing against a rough surface over large area)
o pattern reflects object
o readily form thin scab
contusion
area of bleeding (hemorrhage) into the skin or soft tissue as a result of rupture of blood vessels due to blunt force injury or pressure (BRUISE)
o site of contusion isn’t necessarily the point of impact (baseball bat, hand examples)
hematoma
o focal collection of blood
coup and contre-coup
coup injury is on side of impact and contrecoup is on the opposite side of primary impact (brain moves and hits opposite side of skull)
bruising coloration
red/blue/purple/black can occur…
anytime but often are early
bruising coloration
a bruise with yellow….
is atleast 18 hours old
but the converse is not true
laceration
tearing (not a cut or incision) of the skin or tissue due to stretching, crushing, shearing or avulsing by blunt force injury
o Can have abrasion and/or contusions around edges; rarely patterned
o Soft tissue bridging is the hallmark
o NOT a cut or a stab
fracture
lacerations of bone caused by BFI, that occur when the quantity of force overcomes the strength of bone
o Fatal fractures = skull or C-spine
o Long bones fractures are rarely fatal
Fat embolism syndrome
atlanto-occipital dislocation
dens (axis/C2) is horizontally fractured from C1 and occipital condyles of skull base –> severs respiratory centers in the medulla oblongata
2 processes of post mortem decomposition
autolysis and putrefaction
autolysis
aseptic dissolution of organs by intracellular enzymes
**organs with enzymes (pancreas) autolyze faster than those without (ex: kidney)
putrefaction
tissue breakdown by bacterial action gas formation and bloated abdomen, green discoloration, marbling, skin slippage, degloving of hands, brain liquefaction and loss of hair/nails
marbling in decomposition
due to reaction of hgb and hydrogen sulfide that occurs along the blood vessels resulting in green-purple discoloration of skin
green discoloration in decomposition
due to colon bacteria denaturing hemoglobin with hydrogen sulfide to produce green biliverdin
stabs/punctures
o Depth > length
o Wound edges are sharp and straight, NO tissue bridging and no margin abrasions
o May have extensive internal bleeding with minimal external blood loss
o Single edged weapon wound has 1 blunted margin and 1 V shaped margin
o Double edged weapon 2 V shaped margins
o stab wounds with an L or Y shape indicates twisting of weapon or movement of victim
o “Defense wounds” – palms/back of hands, non-fatal, protective position
chop wounds
o Caused by heavy sharp objects dramatic, may have fine abrasion and contusion at margin
o Associated with a wedged cut into underlying bone
incision
o Sharp edge drawn over tissue; width > depth
o Suicide usually has multiple, superficial groupings; “hesitation marks”
o NO tissue bridging, NO marginal abrasions
contact vs immediate range of fire
Contact – muzzle touches body; essentially all the leaves the gun enters the body
Can be hard, loose, near, angled or partial
Immediate – has stippling (tattooing); bits of gunpowder causing abrasions
Hard to cause stippling on palms and soles
asphyxia
systemic or cerebral hypoxia
