Forensic Medicine

Question 1

what is the major focus of a forensic investigation

Answer 1

why did someone die? cause of death
how did they die? mechanism
what is the manner of death (NASHU) 
Natural
Accident
Suicide
Homicide
Undetermined

Question 2

who can legally certify and sign a death certificate?

Answer 2

physician can only sign if the death was natural

all others are medical examiners 
-accident
suicide
homicide
undetermined

Question 3

major misconceptions

Answer 3

time of death

• not something that can be established in a limited time frame
• rigor mortis- reaches peak at room temp at 24 hours

rapidity of testing
-diagnostic tests take longer times

Question 4

The focus of a forensic examination/inquiry is not natural death (other than to rule out/discern evidence for, or consider circumstances which may be indicative of foul play)

Answer 4

medical examiners have no duty to the family but to the state

if a family is exceptionally against an autopsy, then be suspicious b/c family members are more likely to be involved in the crime

family can be a problem

Question 5

why are there so few autopsies done at hospitals

Answer 5

b/c of lawsuits

so they are performed at ME offices –> but the focus is never on natural death

Question 6

what is the wounding formula

Answer 6

W = E x 1/T x 1/A x K

K = modifying factors (elasticity of the striking object or the tissue being injured etc)

E = Energy transferred = ½ MV^2

T = Period of energy transfer (time)

A = Area of application of force

inversely related to time and area

Question 7

the more young men b/w 15-34, the more violent the crime

Answer 7

testosterone makes you crazy

Question 8

physical environment injuries

Answer 8

mechanical force

• laceration is ALWAYs due to blunt force injury, split of tissue
• abrasion
• contusions
• incise wounds
• gunshot wounds

thermal injuries

• burns
• hypothermia
• hyperthermia

ionizing radiation
-leukemia and lymphomas initated

electrical injuries

atmospheric pressure

• blast injury
• decompression

Question 9

cause of death versus mechanism of death

Answer 9

mechanism:
shock
cardiac arrhythmia/arrest
septic shock

cause of death:
AIDS

Question 10

manner of death examples

Answer 10

natural
accident
suicide
homicide
undetermined

Question 11

three typical wounds produced by blunt force trauma

Answer 11

abrasion
contusion
laceration

Question 12

laceration

Answer 12

soft tissue bridging

depths

Question 13

contusion

extent and severity depends on

Answer 13

amount of force

vascularity of tissue injuried

type of tissue (areolar tissue such as eyelids, bleeds more)

location of the tissue–>
tissue over bones is more easily bruised

easily bruisability - advanced age, cirrhosis, coagulopathies

Question 14

contusions and color?
yellow
blue, purple
brown

Answer 14

yellow- most significant color and its presence indicates that the bruise is at 18 hours or older

blue, purple and red do NOT assist in dating bruises

brown is a mixture of colors and therefore is not useful

Question 15

abrasion

Answer 15

epidermis is injured by friction/scraping or crushing

oozes serum or blood, but does not bleed profusely

torsional marks
rolled edges of skin tell directionality

Question 16

3 types of abrasions

Answer 16

brush- grazing or sliding motion.

impact

patterned- recapitulates the surface appearance of the instrument

passenger windows cause dicing injuries

wheres windshield glass causes other marks

Question 17

stab wound

Answer 17

sharp force injury in which the depth of the wound track is greater than the length of the wound on the skin (deeper than longer)

Question 18

single blade edge

Answer 18

sort of triangle with one edge that isn’t “sliced” like the other edges

Question 19

gun shot wound against skin

close range 1-2 inches

Answer 19

marginal abrasion

stippling deposited (debris) = intermediate gunshot wound

medical examiners can measure what the range/distance from skin was

wad inside a shotgun shell - shows up as a small round circle

pellets

Question 20

shotgun wound on the head

Answer 20

the adult skull has an inner outer table separated by the diploe

in entry wound the outer table of the skull is typically sharply circumscribed and the inner table is beveled

fracture emanating from blunt force or in some cases gunshot wounds, do not ramify across previous fracture lines (don’t cross)

Question 21

mass disasters approach

Answer 21

macro level: the scene

• safeguarding- live people first
• surveying
• documenting
• proper approach to specimen retrieval

Micro level:
biologic materials retrieval and transmittal vs. inorganic specimens/substances

Question 22

37 year old male
uresponsive
no singinficant PMH
diuretic for high blood pressure
50 lb overweight
smoker
hasn't seen physician in 3 years
trauma to his face

looks like shit - looks like there are bumps/bruises and abrasions on the body that are consistent with a fall/trauma

what is the plan of action…

he does have an elevated serum glucose
what is the most likely cause, mechanism and manner of death?

Answer 22

send the body to the ME b/c it looks like there is trauma to the body
he is not being followed by a physician and doesn’t really have a diagnosis

he does have risk factors for sudden cardiac arrest:
high blood pressure
obese
smoker

he has lacerations/abrasions over the bony prominences and no other types of trauma

atherosclerotic cardiovascular disease natural death

Question 23

patient 
drinking bac of .2
black out and head hurts
laceration on the back of his head
being annoying

laceration on the back of his head

based on the appearance of the wound (scalp lac) you conclude…

Answer 23

the lesion is NOT a sharp force injury. He likely fell due to inebriation

the injury is due to blunt force (could be the ground)

soft tissue bridges*** true laceration due to blunt force trauma, may bleed significantly
marginal abrasion

unless it is a very severe injury, the patient doesn’t necessarily need MRI/CT

Question 24

patient with gunshot wounds of his chest two entries on the left and single exit on the right
bilateral hemothorax

the exit is much larger than the entry, what does this imply…

he also shows powder stippling of the shoulder what does this imply…

Answer 24

the feature imply a homicide attempt

exit wound–> this implies high velocity–> much more related to the speed of the projectile than the mass

stippling means it was an intermediate gunshot wound and most likely NOT self inflicted

Question 25

middle aged white male hanging from a noose

rigor mortis and livor mortis of his extremities

tardieu spots
wearing high heeled shoes, hosiery and panties
body is surrounded by angled mirrors and various large picture of naked women

gas-mask type of apparent military equipment on his face

what should you conclude…

Answer 25

autoerotic asyphxia

this is an accidental death

Question 26

3 types of decompisition

Answer 26

putrefactive
-own endogenous flora will go through bowel wall, green patch in the lower abdomen
body is degraded by own bacteria, then secondary bacteria, then insects/magots

adipocere formation
-skin degrades, fat saponification

mummification

Question 27

livor mortis

Answer 27

blood goes to dependent areas

so if they die on their back then blood goes to the back

becomes fixed

can help you tell if a body has been moved

Question 28

those that are burned significantly and survive suffer from what infection

Answer 28

pseudomonis aeruginosa

Question 29

the us homicide rate is….

Answer 29

males 15-34

Question 30

27 year old male
gunshot wound right temple
round marginal abrsaion and powder stiplling around the wound
no gunshot powder residue in the depths of the wound

Answer 30

gunshot wound of injury
intermediate range

implies homicide

Question 31

what is the best method for blunt force injury to the head

Answer 31

an iron rod

Question 32

what case would you send to a qualified pathologist

Answer 32

22 year old man found in the woods and decomposing

72 year old dies after long hospitalization for pancreatic carcinoma. Cause of death is pancreatic carcinoma

elderly man with atherosclerosis and poorly controlled diabetes dead in his home

Question 33

a medical examiner/pathologist is responsible for…

Answer 33

determining the cause and manner of death of cases falling within his/her jurisdiction

don’t work for the police
dont’ work for the families
they work for the public