Injury to the body

Question 1

Define injury

Answer 1

Damage caused by heat, cold, electricity, chemicals and radiation

Question 2

Define lesion

Answer 2

An area of injury, disease, or local degeneration in a tissue causing a change in its structure or funciton

Question 3

What physical factors impact the type and severity of an injury?

Answer 3

Degree of force applied
Area of application of force
Duration of application
Tissue properties

Question 4

What are the mechanical forces of which an injury can be sustained?

Answer 4

Direct impact - perpendicular to skin

Angulation - any direction

Compression - squeeze

Traction - pulling away in opp directions

Torsion - twisting

Shearing - movements in opp direction

Accel/decleration

Question 5

What are the classifications of injuries?

Answer 5

Sharp force
Blunt force
Ballistic

Question 6

What are two examples of sharp force injuries?

Answer 6

Stabs
Incisions

Question 7

What are three examples of blunt force injuries?

Answer 7

Abrasions
Bruises
Lacerations

Question 8

What are examples of ballistic force injuries?

Answer 8

Gunshot
Explosion

Question 9

What is an abrasion?

Answer 9

Injury to the skin surface eg graze or scratch

They are superficial/partial thickness injury to the epidermis of the skin

Question 10

What are contusions?

Answer 10

Burst blood vessels in skin - bruises

Question 11

What are lacerations?

Answer 11

Tear/split of the skin due to crushing

Question 12

What can cause an abrasion?

Answer 12

Crushing by vertical force (imprint)

Scraping by tangential force, graze over broad surface (road rash)

Question 13

Features of an abrasion

Answer 13

Clinically trivial
Slight bleeding
Heal quickly by forming a scab
Leave no scar

Question 14

What causes bruising?

Answer 14

Crushing of the dermal blood vessels by mechanical impact causing leaking of blood from vessels into the skin

Contusion - bruise of internal organs eg spleen, muscle

Question 15

What is patterned bruising?

Answer 15

Trauma to the dermal or intradermal blood vessels that leave a mirror image as to what the wounding weapon may have been

Clustered discoid bruises - fingertip pressure

Question 16

What does a black eye indicate?

Answer 16

Direct trauma, possible skull fractures

Question 17

What does tram-track bruising indicate?

Answer 17

Rod, batton or plank like object

Question 18

What do clustered discoid bruises indicate?

Answer 18

Fingertip pressure - circular

Question 19

What can cause a laceration?

Answer 19

Impact against a flat surface - scalp or facial laceration

Impact by an edged or pointed object - brick, claw hammer, furniture corner

Rotation of tissue on limb/torso (flaying injury) caused by revolving wheel

Excess frictional or tearing forces - senile skin tears, scalping

Question 20

What causes a sharp force injury?

Answer 20

Weapon with sharp cutting edge

Question 21

OWhat are incised wounds?

Answer 21

Superficial sharp force injury caused by slashing motion

Injury is longer than is is deep

Question 22

What are stab wounds?

Answer 22

Penetrating injury as a result of a thrusting motion

Would depth greater than length on the surface

Question 23

Features of incised wounds

Answer 23

Usually penetrates the full thickness of the skin
Clean cut, well defined margins

Profuse bleeding

No associated bruising or abrasion of wound edges

Manner of infliction can be accidental, suicidal or homicidal

Sites of accessibility = suicidal

Sites that are concealed = homicide

Question 24

Features of a laceration

Answer 24

Caused by blunt force
Ragged margins
Marginal abrasion
Associated bruising
Tissue bridging
Slight bleeding
Trace evidence