1. RIMT UNIVERSITY MANDI GOBINDGARH PUNJAB
PresentationO
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Submitted By-
Ahsan Ali
B.Sc (Forensic Science)
4th Semester
4. DEFINITION
OF INJURY :
Section 44 in The Indian Penal Code
44. “Injury”.—The word “injury” denotes any harm whatever illegally caused
to any person, in body, mind, reputation or property.
Definition of Injury: A Wound or Injury is defined as
termination of the natural continuity of any of the tissues of the living body.
Any physical damage to the body caused by violence or accident or fracture
can be called Injury.
4
5. INJURY AND
ITS CLOSELY
RELATED
WORDS
5
Injury
Woun
d
Trau T
ortur
ma e
Injury – Any harm whatever illegally caused to any person, inbody,
mind, reputation or property (S.44 IPC).
Wound – Any breach in the natural continuity of any tissues of theliving
body.
Trauma - Any physical or psychological injury.
Torture – is infliction of intense pain to punish, coerce, oraffordable
sadistic pleas
6. FORENSIC ANATOMY OF SKIN
1.Epidermis
2.Dermis
3.Hypoderm
is
Skin is
composed of:
eight of skin is 4 kg and
surface area in adult is 2 square
8. 8
1. Tensile force (traction-strain)
2. Compressive force(compression-strain)
3. Shearing force(shear-strain)
There are three
types of primary
forces acting over
body:
FORCES ACTING OVER BODY
12. 1. BLUNT FORCE INJURY
The severity, extent & appearance of blunt trauma injury depend on:
• The amount of force delivered to the body.
• The time over which the force is delivered.
• The region struck
• The extent of surface over which the force is delivered.
• The nature of the weapon.
14. MECHANISM OF PRODUCTION
The mechanical force producing abrasion acts on
the skin in one of the following way.
1. Sliding force (friction)
2. Compression force
• Linear/ScratchAbrasion
• Graze Abrasion
Sliding
Force
• Pressure/Crushing
Abrasion
• Imprint/Contact
Abrasion
Compressi
on Force
16. AGE OF
cab.
ff from
ABRASIO
N
It heals from the
periphery by new
growth of
epithelial cells.
DURATION FEATURES
FRESH
INJURY
Bright red colour wound.
2-24 HOURS Lymph and blood dries up leaving red s
2-3 DAYS Reddish brown scab, less tender.
4-5 DAYS Scab is dark brown in color.
5-7 DAYS Scab is brownish red and start falling o
margin
7-12 DAYS Scab dries, shrink and falls off leaving
pigmented skin.
MORE THEN
12 DAYS
becomes thinner.
17. 17
ANTEMORTEM AND POSTMORTEM
ABRASION:
Abrasion produced slightly before or after death cannot be
differentiated even by microscopic examination.
Features Antemortem Post-mortem
Site Anywhere on the body Usually over bony prominences
Colour Bright red Yellowish, translucent and
Parchment-like
Vital Reaction Present Absent
Healing
Process
May be evident Not seen
Inflammation Signs of inflammation present No
21. 21
ANTEMORTEM AND POSTMORTEM BRUISES:
Features Antemortem Post-mortem
TIME During life Within 2-3hrs after death
SWELLING Present Absent
DAMAGE TO
EPITHELIUM
Present Absent
SIZE Proportion to force used Small
EXTAVASTIO
NS OF
BLOOD
More Less
SITE Anywhere Bony prominence
TISSUE
UNDERLYIN
G BRUISE
Tissue stains are
permanent
Stain not permanent
HISTOLOGIC
AL FINDINGS
Inflammatory reaction
present
Absent
COLOR Seen Always dull bluish
22. ARTIFICIAL BRUISES
Artificial bruises are produced due to application of
some irritant substance or juice to the skin
.
Such irritant substance produces inflammation and
vesication simulating bruises.
.
These contusions are produced with malicious intention
implicate someone else
22
to make f
alsealiggations against somebody or to
26. 26
AGE OF
LACERA
TED
WOUND
DURATION FEATURES
FRESH
INJURY
Bleeding or fresh clot is attached; margins are red,
swollen and tender
12-24 HOURS Margins swollen, red and covered by dried blood
clots and lymph.
3-5 DAYS Margins strongly adherent with each other and
covered by dried crust.
6-7 DAYS Crust/scab falls off or can easily be taken off, soft
reddish tender scar.
Few weeks Scar is whitish, firm and painless.
27. 2. FIREARM WOUNDS
A firearm is a thermodynamic machine in which the potential
energy of the gun-powder is transformed into the kinetic energy
of the projectile.
Firearm is any instrument or device designed to propel a
projectile by means of explosion of gases generated by
combustion of an explosive substance.
Gunshot wounds are either penetrating or perforating.
■ Penetrating wounds: The bullet enters an object and does not
28. CHARACTERISTICS OF FIREARM WOUNDS
DEPEND UPON:
Range (distance) of firing.
Shape and composition of the
missiles.
Nature of the firearm, whether
shotgun or rifle.
Direction of firing.
Part of the body struck (head or
trunk).
29. CLASSIFICATION OF
FIREARM WOUND
29
According to
condition of
barrel
According to
muzzle velocity
High velocity
Medium
velocity
Low velocity
Country
made firearm
Rifled firearm
Smooth bore
firearm
30. 30
Different component of firearm and effect on the body:
COMPONENTS EFFECT PRODUCED OVER BODY
B
U
L
L
E
T ENTRY AND EXIT WOUNDS.
ABRASION IS CAUSED
G
U
NS
M
O
K
E SMUDGING AND BLACKING
G
U
NP
O
W
D
E
R
P
A
R
T
I
C
L
E
S
TATTOOING
G
A
S
E
S BLAST EFFECT AND CHERRY RED
COLORATION
F
L
A
M
E
S SCORCHING AND SINGING
M
E
T
A
LP
A
R
T
I
C
L
E
S METAL RING
G
R
E
A
S
E
A
N
DD
I
R
T GREASE COLLAR
31. FEATURES Entry Wound Exit Wound
Size Smaller than the diameter
of bullet
Bigger then the bullet
Edges Inverted Everted, Puckered
Bleeding Less More
Burning,
Blackening,
Tattooing
Present Absent
Bruising,
Abrasion,
Grease collar
Present Absent
Wound track Cherry-red due to
carboxyhaemoglobin
No colour
Fibers of
clothes
Turned in Turned out
G
E
N
E
R
A
L
D
I
F
F
E
R
N
E
C
EB
E
T
W
E
E
N
E
N
T
R
YA
N
DE
X
I
TF
I
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E
A
R
MW
O
U
N
D
32. 32
RANGES EFFECTS
CONTACT Gas, smoke, unburnt
powder enter inside the
wound
NEAR CONTACT
(2.5cm to 7.5cm)
Burning, singeing
present
INTERMEDIATE
(30cm to 60cm)
Tattooing present.
Blacking may be
present.
DISTANT
(More then 60cm)
Burning, singeing,
blackening, tattooing all
absent.
GENERAL EFFECT OF
RANGES OF FIRING
33. 3. SHARP FORCE INJURY
SHARP EDGE TRAUMA IS CAUSED
WHEN OBJECT HAS SHARPED OR
CUTTING EDGE IMPACTS THE
BODY.
35. 35
Mechanism of production
of INCISED WOUND
Incised wound may be produced by light sharp cutting
weapons like kitchen knife, razor, scalpel etc. Moderately
heavy sharp cutting weapons like knife.
The force is delivered over a very narrow area corresponding
with the cutting edge of the blade of weapon.
1. By striking the body with sharp cutting edge.
2. By drawing or swiping action of the weapon on the body.
36. 36
AGE OF
INCISED
WOUND
DURATION FEATURES
FRESH
INJURY
Red with clotted blood.
12 HOURS Margins red, swollen and adherent with bloodand
lymph.
24 HOURS Continues layer of endothelial cells cover the surface
with a scab of dried clot.
2-3 DAYS Vascularized granulation tissue formation.
7 DAYS Scar formation.
38. 4.PIERCING WOUNDS
4.1 STAB
WOUND
Stab wound is a piercing wound produced by
application of mechanical force along thelong
axis of a narrow or pointed object.
Word 'stab' means 'to wound or pierce witha
pointed weapon’.
Stab wounds are produced from penetration
with long narrow instruments having pointed
ends into the depths of the body, whichare
deeper than its length and width.
39. 39
Clinically, stab wounds are of two types:
Penetrating
wound
Weapon enters into
the body cavity
producing only one
wound, i.e. wound
of entry.
1. Perforating
wound
Weapon after
entering into one
side of the body will
come out through
producing two
wounds:
2.
CLASSIFICATION OF
STAB WOUND
Wound of entry:
Through which the weapon
enters the body. It is larger
and with inverted edges.
Wound of exit: Through
which the tip of weapon
emerges out of the body. It is
usually smaller with everted
edges.
40. DIFFERENT TYPES OF
WEAPON CAUSING
DIFFERENT SHAPE OF
WOUNDS
WEAPON TYPE OF WOUND
BLADE WITH SHARP
EDGES BOTH SIDE
SPINDLE SHAPED
BLADE WITH SHARP
EDGE ONE SIDE
WEDGE SHAPED OR TEAR DROP SHAPED
WOUND
ROUND WEAPON ROUND WOUND
WEAPON WITH ONE
SHARP EDGE AND
OTHER SQUARE-OFF
EDGE
FISH-TAIL WOUND
RECTANGULAR
OBJECT
SLIT LIKE OR RECTANGULAR WOUND
41. Type of weapon used can be known.
Dimensions of weapon can be known.
MEDICO- LEGAL
IMPORTANCE OF
MECHANICAL
WOUNDS
Movement of knife in the wound can be known.
Depth of thrust can be known.
Direction of thrust can be known.
Manner of infliction - suicidal/homicidal/accidental
can be known.
Age of wounds can be known.
42. REFERENCE
4 2
Forensic Medicine and
Toxicology for MBBS by
Dr. AnilAggarwal
Review Of Forensic
Medicine And toxicology
by Gautam Biswas
The Essentials of
Forensic Medicine and
Toxicology by K S
Narayan
https://www.pathologyoutlines.com%2
Ftopic%2Fforensicsgunshotwounds.h
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gcXRWswQ&ust=167153636764200
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EQjhxqFwoTCLj8la7MhfwCFQAAAA
AdAAAAABAJ
http://epgp.inflibnet.ac.in/epgpdat
a/uploads/epgp_content/S00001
6FS/P000701/M015740/ET/1464
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