AMERICAN LANGUAGE HUB_Level2_Student'sBook_Answerkey.pdf
Lecture 2. Forensic traumatology.ppt
1. Crimean federal university named after V.I. Vernadsky
Medical academy named after S.I. Georgiyevsky
Department of forensic medicine
FORENSIC MEDICINE.
FORENSIC TRAUMATOLOGY.
FORENSIC EXAMINATION
OF MECHANICAL INJURIES.
2. The bodily injury:
is a violation of an anatomical integrity or/and
physiological function as a result of exposure
to some extraneous environmental factors
(mechanical, physical, chemical, biological).
3. Jurisprudential classification of traumatizing
items
1. Weapons – items specially
constructed to cause injuries to human
or animal (blunt ones – brass knuckles,
knobstick; sharp ones – knife, bayonet,
etc.)
2. Tools – items usually used to do
some kinds of labor (blunt ones; sharp
ones – shovel, axe, etc.)
3. Casual items – nothing from
previous two groups (piece of rock,
club, chair, broken, etc.)
4. Forensic classification
of traumatizing items
1. SHARP ITEMS.
Cutting (incising) ones — these are with a sharp edge
(blade).
Stabbing ones — these are with an extended shape and
a pointed end.
Stabbing-incising ones — these are with both sharp end
and one or several sharp blades.
Chopping ones — these are with a sharp blade but
heavy ones.
Sawing ones — these are with sharp saw-teeth.
2. BLUNT ITEMS.
Items with delimited contacting surface.
Items with prevailing (unlimited) contacting surface.
Oblongated items
5. Injuries classification by their localization
and formation mechanisms:
Isolated trauma – one region of the body is
injured;
Concomitant trauma – few regions of the body
are injured;
Combined trauma – few traumatizing agents of
different origin cause trauma simultaneously.
7. Forensic examination of abrasions
Abrasion — mechanical violation of an epidermis
integrity down to the dermis’ basal layer (not
damaged)
8. Forensic value of abrasions
This is doubtless evidence of foreign force effect.
Sometimes it enables some assessment of
traumatizing item:
sometimes abrasion’s surface represents the
pattern of traumatizing item;
abrasion’s surface could contain some foreign
particles identifying the traumatizing object.
Abrasions are almost always caused by blunt force
effect (some linear abrasions (“scratches”) could be
resulted by the effect of sharp item’s pointed end).
Abrasion’s features could enable determination of
traumatizing force’s motion direction.
Abrasion’s features could enable determination of
time since death.
9. Abrasion’s healing stages
Initial stage of abrasion (before crust is formed);
Crust formation stage – abrasion’s surface dries
and densifies gradually to form crust of lymph,
blood, epidermal particles and minuscule foreign
bodies;
Stage of epithelisation under crust – skin
around the abrasion starts to peel, then crust
starts to exfoliate peripherally and falls off
completely;
Stage of abrasion’s trace (follow-ups) – since
the crust had fallen off there is a pinkish spot
replacing it which disappears gradually.
10. Determination of time since
the abrasion emergence
Time of
abrasion
Abrasion’s appearance
1 hour surface is impressed below the skin’s level, moist, red
6 hours surface is impressed below the skin’s level, red, drying
12 hours surface is impressed below the skin’s level, dark-red, dry
1 day surface is abreast the skin’s level, dry, reddish brown
2 days solid reddish brown crust above the skin’s level
3-5 days solid reddish brown exfoliating crust above the skin’s level
7-10 days solid reddish brown falling-off crust
10-15 days pink or blueish smooth spot replacing the abrasion
17. Types of hemorrhages
petechiae – dotted hemorrhages in the
skin or mucous membranes;
ecchymoses – samall intradermal
hemorrhages up to 0,3-0,5 sm in
diameter ;
pure bruises - blood soaking the soft
tissues;
hematomas - interlaminar separation
of tissues with streaming blood which
is forming a cavity.
18. Features of bruises
Capability to change position
Delayed appearance is possible
Changing of color (“blossoming”)
Possibility of pus formation,
petrification, neoplastic transformation
(2-6 months after trauma (for
hematomas).
19. Forensic value of hemorrhages
По цвету кровоподтека можно судить о
давности его образования.
This is a sign of external violence (but
non-traumatic bruising is possible);
Bruise evidences the impact of a blunt
item;
Bruises sometimes could enable
determination of traumatizing item (if its
shape follows the pattern of the item), or
determination the nature of violence;
Color of the bruise helps to judge the
time since trauma.
20. Determination of time since
the bruising
Time of
bruising
Bruise appearance
1 hour reddish swollen tissues
6-12 hours blueish-crimson swollen tissues
1 day blueish-violet swollen tissues
2-5 days greenish-brown coloring at margins
7-10 days crimson-blue color in the center, middle area is green,
margins are yellowish-brown
10-15 days yellowish spot with uneven margins or normal color of
skin
23. Stale bruise
(about 10 days old)
crimson-blue color in the center,
margins are yellowish-brown
24. Approximate volume of blood-loss due to bleeding
into soft tissues in case if some bones are fractured
Femoral bone 500 – 1000 ml
Bones of leg 300 – 750 ml
Humerus 300 – 500 ml
Pelvic bones Up to 3000 ml
Multiple fractures of various
bones
2500 – 4000 ml
25. Wound:
is the mechanical violation of all the skin’s layers
and/or beneath laying tissues.
(unlike the abrasions wounds always involve basal
layer of skin and as result they always heal with
scar tissue formation)
26. Morphologic features of contused wounds
1. The edges of the wound are usually irregular,
hemorrhaged, abraded;
2. The wound’s ends are rounded in most of the cases;
3. Most of the wounds have tissue interseptions close to
wound’s bottom;
There are massive hemorrhages and crushed tissues in
the underlying tissues, bone fractures can be found.
27. Morphologic features of incised wounds
1. There are linear edges;
2. Both ends are sharp-angled;
3. Depth of the wound at the ends is shallow due to slight
pressure of traumatizing item at the beginning and at
the end of motion. The accomplishing end of a wound
could turn to a scratch;
4. The wound’s length prevails over the depth;
5. Wound’s depth is non-uniform – maximal depth is in the
middle and at the initial end of wound.
31. Morphologic features of stab-incised
wounds:
1. Wound’s depth prevails over external dimentions;
2. Wound’s edges are usually linear;
3. Wound ends’ appearance depends on blade’s construction:
- if it is two-bladed, both ends would be sharp-angled.
- if the blade has one sharp edge and one blunt edge, one end of the wound
would be sharp-angled and the other one would be rounded or U-shaped.
- broad blunt edge of the blade (2 mm or wider) could cause little additional
cuts of the skin emerging from U-shaped end (so called “little swallow’s tail”).
4. If the knife’s taking-out pathway is different from pathway of it’s penetration
there would be an additional cut close to the sharp end of the wound (so
called “big swallow’s tail”).
35. Morphologic features of
stabbed wounds
1. Little dimensions (length and width) of inlet
opening
2. Significant length of wound canal
3. Shape and dimensions of inlet opening
depend on traumatizing item’s transverse
section pattern
4. Edges of inlet opening could be torn and
abraded
37. Morphologic features of chopped wounds:
1. Wound’s edges are usually linear;
2. Wound’s edges could be abraded and hemorrhaged due to contusional
force applied;
3. Violation of bones integrity is very frequent. Traces of chopping are often
found on the surface of bones and cartilages;
4. If there is a wound at the hairy part of the head, damages of hair are possible
(crashing of them, smashing their ends);
5. Wound’s shape and types of it’s end depend on the type of copping item
penetration:
39. Forensic value of wounds:
Wounds are doubtless evidence of extraneous violence;
Traumatizing force’s direction of motion could be
determined by investigation abraded edges appearance and
localization, skin’s flaps localization, wound’s canal direction;
Wounds evidence individual features of traumatizing items
much more than hemorrhages do. Shape and features of
contused wound give more complete idea of what was the
pattern of blunt item contacting surface.
Morphologic features of stab-incised wounds (lengths of
central incision and of wound’s canal, wound’s ends
appearance) enable determination of blade’s individual
features).
Knowing healing stages sometimes there is a possibility to
evaluate time since trauma.
40. Age of the wound
Healing by the first intention is inherent to stabbed, stab-incised,
incised wounds, i.e. there are no massive destructions of tissues or
skin deffects.
In normal (not complicated) healing of that type immature scar
of little wound forms up to 6th-7th day.
Healing by the first intention takes place then damaged tissues are
vitally incapable, necrotized or if wound is gaping too much:
There are three stages of that type of healing:
Stage of inflammation and necrosis, often purulent. It usually
lasts up to 3-10 days, if inflammation is purulent it could take
up to 60 days or longer.
Granulation stage - from 5-6 days to few weeks or months.
Epithelization and scarring stage – scar formation lasts up to
6-8 months.
41. Factors influencing bone’s demolition
process
Type of bone’s deformation
Extraneous force effects’ parameters:
Extraneous force velocity (speed of approaching of
traumatizing force):
impact
compression
Combination of impact and compression
Extraneous energy value
Traumatizing item individual features
Bone’s construction features
42. TYPES OF BONE DEFORMATION
Uniaxial compression
Extension
Shift
Bending
Rotation
43. Types of bone fractures
By their morphology:
Splintered fracture – if there are splinters or fragments of bone;
Laminar fracture – loss of bone’s anatomical integrity with
no macroscopic continuity impairment:
“green branch“ type fracture (due to bending);
валикообразные" переломы (от сжатия).
By the place where the traumatizing force has been applied:
Local (direct or contact) ones – fracture exactly at the spot there the
traumatizing force has been applied.
Constructive (indirect) ones - fracture far from the exact spot there the
traumatizing force application is formed due to deformation of bony
complex.
By radius of curvature (rib, hyoid bone) :
bending fracture – then radius of curvature decreases and the bone’s ends
converge one to another;
extension fracture - then radius of curvature increases and the bone’s ends
diverge one from another.
