injury to the body

Question 1

define injury

Answer 1

wound

also damage caused by heat, cold, electricity, chemicals and radiation

Question 2

define lesion

Answer 2

any area of injury, disease or local degeneration in tissue causing a change in its structure or function

Question 3

defect

Answer 3

unknown mechanism

Question 4

physical factors

Answer 4

degree of force applied
area of application of force
duration of application 
direction of application 
tissue properties

Question 5

kinetic energy

Answer 5

imparted to the tissues when a moving object strikes the body or the moving body strikes an object
velocity is the most important factor in wounding potential

Question 6

mechanical force (7)

Answer 6

impact 
angulation 
compression 
traction
torsion
shearing 
acceleration/deceleration

Question 7

injury classification

Answer 7

sharp force: stabs, incisions
chop wounds
blunt force: abrasions, bruises, lacerations
ballistic: explosions, gunshots: rifle, shotgun

Question 8

blunt force injuries

Answer 8

caused by impact with a blunt object

result in abrasions, contusions and lacerations

Question 9

abrasions

Answer 9

graze/scratch 
superficial/partial thickness skin injury to the epidermis
- crushing by vertical force (imprint)
- scraping by tangenital force 
clinically trivial, slight bleeding 
heal quickly and often leave no scar

Question 10

contusions

Answer 10

bruises
crushing of the dermal blood vessels by mechanical impact causing leakage of blood into the skin
contusion bruising of internal organs
patterned bruising: tram track, clustered discoid, black eyes

Question 11

interpretation of bruising

Answer 11

• collection of blood can form a haematoma in a place other than the site of injury e.g. scrotum, palm, sole, eye socket
• amount of blood in the extraversion is dependent on the vessel size and number of vessels damaged
• disordered blood coagulation
• depth at which bruise develops
• skin colour
• tracking to another location
• appearance may be delayed and ageing is often inaccurate
• size rarely reflects severity of impact and shape rarely reflects shape of causal object

Question 12

lacerations

Answer 12

tear/split of the skin due to crushing
partial/full thickness
can impact underlying bone
caused by: impact against a flat surface, impact by an edged or pointed object, rotation of tissue on a limb/torso, XS frictional/tearing forces

Question 13

sharp force injuries

Answer 13

caused by any weapon with a sharp cutting edge
superficial or penetrating
incised wounds or stab wounds

Question 14

incised wounds

Answer 14

superficial injury caused by slashing motion
longer on the skin surface than it is deep
usually penetrates the full thickness of the skin
clean cut, well defined margins - complete division of all tissues within the wound tract
no associated bruising or abrasion around the edges
bleed profusely

Question 15

stab wounds

Answer 15

penetrating injury resulting from thrusting motion
depth greater than surface length
clean cut, well defined margins
involves full thickness of the skin and extends into underlying tissues
no associated bruising or abrasion at the wound edges unless knife is inserted to the hilt

Question 16

laceration vs incision

Answer 16

laceration/ incision (F, M, A/B, TD, B, E)

• caused by blunt force/sharp force
• ragged margins/clean margins
• marginal abrasion, associated bruising/no associated abrasion or bruising
• tissue bridging/clean division of tissues along wound tract
• slight bleeding/profuse bleeding
• trace evidence/no trace evidence

Question 17

atypical stabbing weapons

Answer 17

swords, sabres
razors, scalpels, craft knives, box cutters
scissors
chisels
poker, pitchfork 
deliberately modified tools 
improvised weapons
glass, plastic, crockery shards

Question 18

chop wounds

Answer 18

heavy bladed instruments
abrasion +/- bruising of wound margins from wide blade
incised edges crushed on entry of the thick blade
variant of incision
longer than it is deep