Forensic Pathology

Question 1

Rigor mortis

Answer 1

Usually occurs approx 24-48 hrs uniformly.

After rigor mortis, a period of secondary flaccidity occurs.

Question 2

Algor mortis

Answer 2

Change in body temperature to reach room temperature.

Question 3

Livor mortis

Answer 3

Pooling of blood post mortem. Can be either fixed or unfixed.

Question 4

Putrefactive decomposition

Answer 4

Occurs when exposed to air and moisture. Bacteria decompose the body. Bacteria at the cecum are usually first to invade.

Question 5

Adipocere decomposition

Answer 5

Occurs in bodies submerged in water. Hydrolysis of lipids allows for a wax-like covering of the body.

Question 6

Mummification

Answer 6

Occurs in deserts where there is no moisture of microbes, beetles, etc.

Question 7

Who can legally certify a death certificate for natural death?

Answer 7

MEs, coroners, justice of the peace, etc.

Question 8

MEs are required to sign death certificate for which manners of death? (4)

Answer 8

Accident
Suicide
Homicide
Undetermined

Question 9

Cause of death vs. manner of death

Answer 9

COD is what killed the person, while manner of death is the MEs opinion (homicide, suicide, etc.)

Question 10

2 major roles of the ME

Answer 10

Assign a COD
Render an opinion as to manner of death

ME has no duty to families, they work for society at large.

Question 11

Mechanical forces causing injury (6)

Answer 11

Abrasions
Lacerations
Contusions
Incise wounds
Gunshot wounds
Blast injury

Question 12

Thermal injuries (3)

Answer 12

Burns
Hyperthermia (heat cramps, heat exhaustion, heat stroke)
Hypothermia

Question 13

What are the 5 major categories of injury caused by physical environment?

Answer 13

Mechanical force
Thermal injuries
Ionizing radiation
Electrical injuries
Atmospheric pressure

Question 14

What 2 systems are mostly affected by radiation?

Answer 14

Hematopoietic and lymphoid systems

Question 15

What is the first problem that occurs when radiation is given more than 0.15 sv?

Answer 15

Temporary sterility

Question 16

Main sites of injury and main signs and symptoms for:

0-1 sv

1-2 sv

2-10 sv

10-20 sv

> 50 sv

Answer 16

0-1 sv: none, none.

1-2 sv: lymphocytes, moderate granulocytopenia and lymphopenia.

2-10 sv: bone marrow, leukopenia, hemorrhage, hair loss, vomiting.

10-20 sv: small bowel, diarhea, vomiting, fever.

> 50 sv: brain, ataxia, coma, convulsions.

Question 17

Accurate death certification schema:

Answer 17

Immediate COD (mechanism) (pneumonia)

Due to:

(Proximate) COD (COPD)

Manner of death (natural)

Question 18

3 types of wounds from blunt force trauma

Answer 18

Abrasion
Contusion
Laceration

Question 19

Wounding formula

Answer 19

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

K is modifying factors (elasticity, etc)
E is energy transferred = 1/2 MV^2
T is period of energy transfer (time)
A is area of application of force

Question 20

Contusion

Answer 20

A bruise that results from hemorrhage into soft tissues due to rupture of subcutaneous BVs by blunt injury.

Question 21

What is the epidermis like in a contusion?

Answer 21

It is intact and therefore a contusion does not bleed externally, but may be seen from skin or internal organs.

Question 22

What do yellow, blue/purple/red and brown bruises suggest in dating a contusion?

Answer 22

Yellow is most significant and its presence indicated the bruise is 18 hrs or older.

None of the others are helpful.

Question 23

Abrasion

3 types of abrasions

Answer 23

A wound where the epidermis is injured. It bleeds externally, but not profusely.

Brush (sliding/gliding)
Impact
Patterned (when abrasion reflects the surface of appearance of the instrument)

Question 24

Stab wound

Answer 24

Sharp force creates a wound track that is greater thab the length (deeper than wide).

Question 25

3 major categories of guns and their subtypes

Answer 25

Long guns

• bolt/lever action
• semiautomatic
• fully automatic

Smooth bores

Hand guns

• revolvers
• semiautomatics

Question 26

What is the wounding formula for guns/projectiles?

Answer 26

KE = 1/2m x V^2

Velocity is much more important than mass

Question 27

What is seen on entry wounds in:

Contact range

Intermediate range

Distant range

Answer 27

Contact range - marginal abrasion; soot/powder in depths of wound.

Intermediate range - marginal abrasion, powder/tattooing/stipping around wound

Distant range - marginal abrasion, no powder/tattooing/stipping, no soot/powder in depths of wound.

Question 28

What is the inner and outer table separated by in the adult skull?

Answer 28

A diploe

Question 29

How are entry and exit wounds described in the skull?

Answer 29

Entry wounds of outer table is sharply circumscribed, while the inner table is beveled.

If the buller has an exit wound, it is the opposite setup.

Question 30

Low velocity leads to:

High velocity leads to:

Answer 30

Low - small entry, no exit (or small exit)

High - relatively small entry, big exit.