Definitions
• Injury: Any harm, whatever illegally, caused to any
person in body, mind, reputation or property (Sec. 44 IPC).
• Wound: Clinically, it means any injury where there
is breach of natural continuity of skin or mucous
membrane. In medico-legal practice, the terms wound
and injury are synonymous, but strictly wound will
include any lesion, external or internal, caused by
violence, with or without breach of continuity of skin.
Classification of Wounds/Injuries
Injuries can be classified in many ways:
Based on Causative Factors
- Mechanical or physical injuries (produced by physical
violence, Fig. 11.1)
i. Abrasion
ii. Bruise or contusion
iii. Lacerated wound
iv. Incised wound
v. Stab wound
vi. Firearm wound
vii. Fracture/dislocation of bone, tooth or joint.
• Blunt force trauma is caused when an object, usually
without a sharp or cutting edge, impacts the body
or the body impacts the object. Abrasion, contusion,
laceration and fracture/dislocation of bone of tooth
result from such an impact.
• Sharp force trauma occurs when an object with a
sharp or sharpened edge impacts the body. Incised
and stab wounds results from such trauma.
• For any given amount of force, the greater the area
over which it is delivered, the less severe the wound
(as applicable to blunt and sharp trauma).
The severity, extent and appearance of blunt trauma injuries
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
- Thermal injuries
Due to application of heat
a. General effects (may not cause any visible injury),
e.g. heat cramps and heat stroke
b. Effects of local application, e.g. burns and scalds
Due to application of cold
a. General effects, e.g. hypothermia
b. Local effects, e.g. frost bite and trench foot
Fig. 11.1: Mechanical injuries caused by blunt and sharp objects
166
- Chemical injuries
i. Irritation: Due to application of weak acids, alkalis,
plant or animal extracts
ii. Corrosion: Due to application of strong acids or
alkalis
- Miscellaneous injuries
i. Electrical injury
ii. Radiation injury: Due to X-ray, UV radiation, radio-
active substances
iii. Lightning injury
iv. Blast injury
Based on Severity of Injury (Legally)
i. Simple
ii. Grievous, which may or may not be dangerous
Based on Nature of Injuries (Medico-legally)
i. Suicidal
ii. Homicidal
iii. Accidental
iv. Defense wounds
v. Fabricated or self-inflicted wounds
Based on Time of Infliction
i. Antemortem—recent or old
ii. Postmortem
Abrasion
Definition: Removal of the superficial epithelial layer
of the skin, usually the epidermis, by friction against
rough surface. Cyclists often refer to abrasion as 'road
rash'.
Types (Fig. 11.2)
i. Scratch/linear abrasion: It is caused by a sharp or
pointed object passing across the skin, such as
fingernails, thorn or pin. Surface layers of skin are
collected in front of the object, which leaves a clean
area at the start and tags at the end (Fig. 11.3).
Fingernail abrasions are seen in throttling, sexual
attacks and child abuse.
ii. Graze abrasion (sliding/scrape/grinding abrasion)
• Grazes are caused by horizontal or tangential
friction between the skin and the hard rough
surface.1 They show uneven, longitudinal parallel
lines, which indicate the direction in which the
force was applied (epidermis being heaped up at
the opposite end) (Fig. 11.3).
• Most common type of abrasion and commonly seen
in road traffic accidents.2 Particles of glass, gravel
or dirt may be embedded in such wounds.
Fundamentals of Forensic Medicine and Toxicology
Fig. 11.2: Types of abrasions
Fig. 11.3: Direction of force in an abrasion
• Brush burn: Graze abrasion involving wider area
such as the back, caused by violent rubbing against
a surface, as in dragging along over the ground.
Such injuries, when dry, become firm, even though
no true ‘scab’ is present.3-5
• Friction burn: An extensive, superficial, reddened
excoriated area with little or no linear mark, occurs
when the skin is covered by clothing (element of
thermal damage is present).
iii. Pressure abrasion (crushing/friction abrasion): It
is caused by direct impact or linear pressure of a
rough object over the skin. The slight movement
directed inwards results in crushing the superficial
layers of the cuticle and bruising underneath, e.g.
nooses or ligatures in hanging and strangulation.
iv. Imprint abrasion (impact/contact/patterned
abrasion): It is caused when the force is applied
perpendicular to the skin, the cuticle gets crushed
at the point of impact and bears the imprint of the
object causing it.
Duration Features
Fresh Bright red, oozing of serum and some blood.
2-24 h Exudation dries to form a reddish scab,
comprising of blood, lymph and epithelial
cells. Polymorphonuclear cells infiltrate (scab
formation).
2-3 days Reddish-brown scab, less tender.9
4-5 days Scab is dark brown in color.
5-7 days Scab is brownish black and starts falling from the margins. Epithelium grows and
covers defect under the scab (epithelial
regeneration).
7-12 days Scab dries, shrinks and falls off, leaving de-
pigmented area underneath. It gradually
gets pigmented in due course of time
(subepidermal granulation).
12 days Epithelium becomes thinner and atrophic.
New collagen fibres are prominent. Basement
membrane is present and vascularity of the
dermis decreases (regression).
Injuries 167
• The abrasion in slightly depressed below the
Table 11.1: Age of abrasion
surface.
• It tends to be focal and is commonly seen over
bony prominences, where a thin layer of skin
covers the bone.
– Imprint abrasion becomes more defined when
injured cuticle dries up and becomes brownish
and parchmentized, in contrast with the
surrounding uninjured skin surface.
• Pattern abrasion is a variation of pressure
abrasion.6
• When a person is knocked down by car, pattern of
the radiator grill, headlamp rim or tyre-tread mark
may be seen on the skin.7 Imprint of bicycle chain,
serrated knife are other examples.
• Teeth bite marks are included in this category,
though they may produce contusion or laceration,
depending upon the force applied.8
• UV light may be used to visualize the pattern
injuries not apparent with visible light.
off
Human bite can occur during sexual behavior/assault, child
abuse, self-defense, self-inflicted or a child biting another
child. Bite may tear or crush, resulting in two U-shaped
marks, corresponding to the upper and lower anterior six
teeth (canine to canine) and separated by an open space
of about 2.5-4 cm, which can be contused from teeth
pressure. Most victims of a criminal act are women and
breast is the most common location. Male victims are more
frequently bitten on the arms.
Age of Abrasion
It produces minimum bleeding, heals rapidly and leaves
no permanent scarring on healing (Table 11.1).
Differential Diagnosis
i. Postmortem insect bites of the skin caused by ants
or cockroaches produce dry, pale brown lesions
with irregular margins and are arranged in a linear
pattern. Most commonly found at mucocutaneous
junctions—around the eyelids, nose, mouth, ears,
axilla, groins and genitalia. Vital reaction is absent.
• It may also resemble powder stippling (firearm
injury).
ii. Excoriation of skin by excreta and diaper rash may
be misinterpreted as abrasions.
iii. Dry skin of scrotum and vulva gives a reddish
brown or yellow coloration when exposed to the
open air.
iv. Decubitus/pressure ulcers (bed sores): These are due
to pressure necrosis of the skin in a bedridden
caused by prolonged compression of soft tissue
between bony prominence and external surface.
v. Postmortem abrasions (refer to Diff. 11.1): In doubtful
cases, a histopathological examination may be
needed.
Circumstances of Abrasions
i. Usually it is seen in accidents and assaults.
ii. Hysterical women may produce abrasions over
accessible areas, like the front of forearm or over
the face, to fabricate charge of assault.
iii. Abrasions on the face or body of the assailant
indicate a struggle.
iv. Person collapsing due to a heart attack may fall
forward and receive abrasions on the forehead,
nose and cheek, but there will be no injuries on
the upper limbs.
v. Abrasions may be produced on the palmer surface
of hands in a conscious person, who while falling
puts out his hands to save himself.
vi. Alcoholics tend to fall backwards and strike the
occiput on the ground.
vii. Abrasions over the cornea may cause corneal
opacity which may restrict vision permanently,
amounting to grievous hurt (Sec. 320 IPC).
Differentiation 11.1: Antemortem and postmortem abrasion
S.No. Feature Antemortem abrasion Postmortem abrasion
- Site Anywhere on the body Usually over bony prominences
- Color Bright red Yellowish, translucent and parchment-like
- Exudation More, scab slightly raised Less, no scab
- Vital reaction Present Absent
- Healing process May be evident Not seen
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Fundamentals of Forensic Medicine and Toxicology
- Healing process May be evident Not seen
Note: Abrasions produced slightly before or after death cannot be differentiated even by microscopic examination.
Medico-legal Importance
• Abrasions give an idea about the site of impact and
direction of force.
• They may be the only external signs of serious
internal injury.
• Patterned abrasions are helpful in connecting the
wound with the causative weapon.
• Age of injury can be determined which helps to
corroborate with alleged time of assault.
• In open wounds, dirt, dust, grease or sand is usually
present which helps to connect the injuries to the
scene of crime.
• Character and manner of injury may be known from
its distribution:
i. In throttling, crescentic abrasions made by finger-
nails are found on the neck.
ii. Abrasions on the victim may show whether the
fingernails of assailant were long, irregular or
broken.
iii. In smothering, abrasions may be seen around the
mouth and nose.
iv. In sexual assaults, abrasions may be found on the
breasts, genitals, inside of the thigh and around
the arms.
Patterned injuries can be subdivided according to the type
of force involved:
• Blunt force injuries: These are the most commonly seen
group. Abrasions may preserve patterns well, especially
if the force is applied perpendicular to the skin surface.
Bruises may also reproduce patterns well, particularly if
they are intradermal. Lacerations less frequently show a
well-defined reproduction of the shape of the causative
agent.
• Sharp force injuries: Stab wounds may show
characteristics of a specific type of blade (e.g. ‘fish-tail’
appearance). Distinctive patterns may be seen with the
hilt, or a stab wound with Phillips head screwdrivers or
scissors.·
• Gunshot wounds: Contact entry wounds (may have sight
marks) and shotgun wounds (e.g. wad marks) may
produce distinct patterned injuries.
• Other miscellaneous wounds and marks e.g., fern-like
pattern with lightning strikes, tool marks on internal
structures (such as cartilage).
Medico-legal importance: Connect a particular weapon or
object to an injury, which may allow a perpetrator to be
linked to the crime and/or enable better understanding of
the events surrounding a death.
Bruise/Contusion
Definition: Bruise is the extravasation of blood in the
subcutaneous/subepithelial tissues due to rupture of
blood vessels, usually capillaries as a result of blunt
force injury or pressure.
• ‘Bruise’ is derived from old English word ‘brysan’
which means ‘to crush’.
• Usually, there is no loss of continuity of the overlying
skin.
• ‘Bruise’ implies that the lesion is observed through
the overlying intact skin as bluish purple
discoloration and swelling of the involved area, while
a 'contusion' is a bruise within an organ or tissues,
such as muscles, liver or mesentery.
Causes
i. By application of blunt force viz. blow with fists,
sticks, iron-bar, cane, whip or chain.
ii. From compression, like pressing fingers.
Classification
Bruise is classified into three types depending on its
situation:
i. Intradermal bruise: Bruise lies in the immediate
subepidermal layer. It is made by impact with a
patterned object and hemorrhage is sharply
defined.
Injuries 169
ii. Subcutaneous bruise: It is situated in subcutaneous
tissue, often in the fatty layer and the edges are
blurred. Most common type of bruise caused by
blunt object, and appears soon after injury as dark
red swelling.
iii. Deep bruise: Bleeding deeper to the subcutaneous
tissues. It may take hours to 1-2 days to appear at
the surface (delayed bruising). Therefore, one more
examination should be carried out 24-48 h after
first examination. Infrared photography may
demonstrate such bruises, if suspected initially.
Factors Influencing the Bruise
i. Type of tissue/site involved
• Soft, lax and vascular tissues, such as face, scrotum
and eyelids develop large bruises even with little
force.10
• In tissues which are strongly supported, contain
firm fibrous tissue and are covered by thick dermis,
e.g. abdomen, back, scalp, palms and soles, even a
moderate violence may produce only a small
bruise.
• Bruising of scalp is better felt than seen.
• Bruising is more marked on tissues overlying bone.
• In boxers and athletes, bruising is much less,
because of good muscle tone.
• Chronic alcoholics with cirrhosis and individuals
taking aspirin, bruise easily.
ii. Age: Children and elderly bruise more easily
because of softer tissue and delicate skin in the
former, and loss of subcutaneous supportive tissue
and cardiovascular changes in the latter.
iii. Sex: Women tend to bruise more easily than men
because tissues are more delicate and subcutaneous
fat is more. Obese people bruise more easily than
lean because tissues are more delicate.
iv. Color of skin: Bruising is more clearly seen and
recognized in fair skinned persons than those with
dark skin, in whom they may be better felt than
seen.
v. Natural diseases: Prominent bruising following
minor trauma is seen in persons suffering from
atherosclerosis, purpura hemorrhagica, leukemia,
hemophilia, scurvy, bleeding diathesis, vitamin K
and prothrombin deficiency, and in phosphorus
poisoning.
vi. Gravity shifting of blood (ectopic/migratory bruise):
It is responsible for the appearance of bruises at a
site other than the site of injury, e.g. black eyes.
Blood will track along the fascial planes (or
between muscle layers) along the path of least
resistance and may appear where the tissue layers
become superficial. Thus, site of bruise does not
always indicate the site of injury.
• Grey Turner’s sign: Ecchymosis seen over flank or side
of abdomen, occurring due to extensive retroperitoneal
hemorrhage. This sign takes 24–48 h to develop.
• Cullen’s sign: Bluish-black discoloration of the
periumbilical skin due to extensive retroperitoneal or
intraabdominal hemorrhage. This may be caused by
ruptured ectopic pregnancy or acute pancreatitis.
Patterned Bruise
Bruise may indicate the nature of the weapon, especially
when death occurs soon after infliction of injury.
i. A blow from a solid body, such as hammer or a
closed fist produces a rounded bruise.
ii. Blows with a rod, stick or a whip produce two
parallel, linear hemorrhages (railway line or tram-
line type). The intervening skin appears
unchanged (Fig. 11.4).
Mechanism: The weapon sinks into the skin on
impact, so that the edges drag the skin downwards
and the traction tears the marginal blood vessels.
The centre compresses the skin, which causes little
or no damage to the vessels. When the impact is
released, the blood flows back into the injured
marginal zones and leaks into tissues (Fig. 11.5).
iii. A woven, spiral or plaited ligature may produce a
patterned bruise.
iv. Suction or biting on the sides of the neck or the
breasts during love making/sexual intercourse
produces elliptical patterned bruises.
Fig. 11.4: Patterned bruise
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Fundamentals of Forensic Medicine and Toxicology
Table 11.2: Age of bruise
Duration Color
Fig. 11.5: Formation of ‘tram-line contusion’
Deep tissue and organ contusion
• Internal organs can also get contused; contusion of
the brain may cause confusion, coma and death.
• Contusion in vital centres, e.g. which control
respiration and blood pressure can be fatal even
when very small.
• Small contusions of heart can cause serious
disturbances of normal rhythm or stoppage of cardiac
action and death.
Dating/Age of Bruise
Consistent, reliable microscopic dating is not possible
and color changes in resolution of a contusion is not
always a reliable indicator of its age. However, methods
used to date a bruise are:
i. Histology (only in postmortem situation)
ii. Color changes (visual examination)
iii. Calorimetry
iv. Spectrophotometry
• Bruises heal by destruction and removal of
extravasated blood.
• The extravasation of blood is followed by an
inflammatory reaction that causes vasodilation and
attracts macrophages which breaks down
hemoglobin to biliverdin. Biliverdin is then broken
down by the enzyme biliverdin reductase to yellow
color bilirubin. As hemoglobin is broken down, some
of its iron is released and combines with ferritin
which gives rise to hemosiderin.
• Color change starts at the periphery and extends
inwards to the centre.
• The time required for bruising to clear is extremely
variable and is only a general guideline in
interpreting the age of the bruise (Table 11.2). It
should only be stated whether the bruise is recent or
old.
• Sub-conjunctival hemorrhage does not show similar
color changes owing to hemoglobin being kept
oxygenated by air. It is red at first, then becomes
Fresh Red (oxygenated blood)
Few hours to 3 days Blue (deoxyhemoglobin)11
4-5 days Bluish black to brown (hemosiderin)12
5-6 days Green (biliverdin)13
7-12 days Yellow (bilirubin)
2 weeks Normal
yellow and finally disappears.14 Similar changes are
seen in meningeal hemorrhages owing to O2
supplied from CSF.
• Healthier the individual, the more rapid will be the
healing. A bruise takes a much longer duration to
heal in the old than in the young. In old age, it may
remain for 4-5 weeks. Bruises of soft loose tissues,
like those surrounding the eye resolve faster.
• Environmental lighting may slightly alter the color
of the bruise. Drugs, such as steroids may change
the rate of bruise dispersion, and interventions, such
as ice packs or heat treatment may add to variability.
• Bruises of the same age may show different color
progression, so that variation in color does not
necessarily mean that there have been multiple
episodes of injury.
• Not all bruises pass through a yellow phase before
they resolve.
• Dating a bruise may be helpful in determining the
veracity of the informant and together with other
data may justify further investigation into a particular
case.
• Hemosiderin is a granular brown iron-storage complex
composed of ferric oxide, commonly found in macrophages
and derived from breakdown of hemoglobin.
• Biliverdin is a green pigment formed as a byproduct of
heme breakdown.
• Bilirubin was discovered by Virchow in 1849, who called
the yellow pigment ‘hematoidin’.
Complications
i. Multiple contusions can cause death from shock
and internal hemorrhage.
ii. Gangrene and death of tissue can result.
iii. Bacterial infections, especially by Clostridia can
occur.
iv. Pulmonary fat embolism may occur.
Medico-legal Importance
• It is advisable that a medical officer should re-
examine the patient after 24 h, as by this time the
bruises are clearly visible.
Injuries 171
• Age of the injury can be determined by the color
changes.
• Degree of violence may be determined from their
size.
• Patterned bruises may connect the victim and the
object/weapon, e.g. whip, chain, cane or ligature.
• To confirm at postmortem examination, deep
incisions are made at suspected sites, which show
ecchymosis (Diff. 11.2 and 11.3).
• Contusions can be produced postmortem, if a severe
blow is given to the body within few hours after
death.
• Bruises may be fabricated by applying juices of
marking nut or calotropis to incriminate others, or
in defense of a crime.
• Surgical removal of cornea can result in hemorrhage
into the eyelids, identical with antemortem trauma.
• Character and manner of injury may be known from
its distribution:
i. When arms are grasped there may be 3-4 bruises
on one side (corresponding to fingers) and one
larger bruise on the opposite side (thumb).
ii. Bruising of the arm may be a sign of restraining a
person.
Differentiation 11.2: Antemortem and postmortem bruise15
S.No. Feature Antemortem bruise Postmortem bruise
- Swelling Present Absent
- Damage to epithelium Present Absent
- Extravasation of blood Present Absent
- Coagulation Present Absent
- Infiltration of the tissues with blood Present Absent
- Color changes Seen Uniform color
- Margins Merge with surrounding area Sharply demarcated
- Appearance More marked in victims who survive for sometime
Less marked
Differentiation 11.3: PM staining and bruise
S.No. Feature PM staining Bruise
- Cause Distension of vessels with blood in dermis Rupture of vessels which may be superficial
or deep
- Cuticle Not abraded May be abraded
- Site Occurs over extensive area of the most dependent parts Occurs at the site of and surrounding the injury,
may appear anywhere on the body
- Appearance No elevation of involved area Often swollen, because of extravasated blood and
edema
- Margins Clearly defined Merge with the surrounding area
- Color Uniform bluish-purple color Different colors, depending on the age of bruise
- On incision Blood is seen in blood vessels which can be easily washed away, subcutaneous tissues are pale Extravasation of blood into the surrounding
tissues, cannot be washed by water,
subcutaneous tissues are deep reddish-black
- Effect of pressure Absent in areas of the body which are under even slight pressure
Lighter over the area of pressure or support
- Superimposed abrasion Not present May be present
- Microscopically Blood cells are found within the blood vessels and there is no evidence of inflammation
Blood cells are found outside the blood
vessels, evidence of inflammation present
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Fundamentals of Forensic Medicine and Toxicology
iii. Small bruises along with nail marks on the inner
aspect of thighs of a woman may indicate sexual
assault. Typical small bruises (six-penny bruises) are
produced by forcible poking or pressure of
fingertips.
iv. Bruising of the shoulder blades indicates firm
pressure on the body against the ground or other
resisting surface.
v. In manual strangulation, position, number of
bruises and nail marks give an indication of the
position of the assailant.
vi. Bruises found in ‘soft’ sites in a child such as cheeks
or trunk and multiple bruises in various stages of
healing suggest abuse.
Bruises are of lesser value than abrasions because:
• Their size may not correspond to the size of the weapon.
• They do not indicate the direction in which the force
was applied.
• They may become visible after few hours or even 1-2
days after injury.
• They may appear at a distance away from the actual site
of injury. It may not indicate the point of trauma.
Lacerated Wound
Definition: Laceration is tearing or splitting of skin,
mucous membranes, muscles or internal organs caused
by either a shearing or a crushing force and produced
by application of a blunt force to a broad area of the
body.
If the blunt force produces extensive bruising and
laceration of deeper tissue, it is called crush injury.
Types
i. Split lacerations: Occur when soft tissues are
sandwiched between a hard unyielding deeper
structure and the agent applying the force. Scalp
lacerations occur due to the tissues being crushed
between the skull and some hard object.16
Incised-looking lacerated wounds: When the skin
is closely applied to the bone and the subcutaneous
tissue is scanty, blunt force may produce a wound
which by linear splitting of the tissues resembles
an incised wound.17
Sites: Scalp, forehead, eye brows, zygoma, iliac
crest, lower jaw, perineum and shin.18
ii. Stretch lacerations: Result from a heavy forceful
frictional impact of blunt forces exercising localized
'pressure with pull'. Overstretching of the skin and
subcutaneous tissues may cause lacerations with
flapping of the skin which may indicate the
direction of application of force.
They are seen in run over by motor vehicle,
kicking and in compound fractures.
iii. Avulsion or grinding compression: Produced by
force (shearing force) delivered at an oblique or
tangential angle to detach (tear off) a portion of
traumatized skin surface or viscus (tissue/organ)
from their attachment (Fig. 11.6).
• Commonly seen in road traffic accidents where
the rotating force of a wheel tears off the skin over
a large area. This is called flaying and most
frequently occurs on the legs.19
• Amputation injuries are a type of avulsion injury
in which an entire extremity or portion thereof is
severed from the body.
• The most severe is a decapitation injury, in which
the head separates from the body.
iv. Tears: Tearing of skin and subcutaneous tissue can
occur from localized impact by or against some
hard, irregular object like car door handle, radiator
mascot or from blows with broken glass bottles.
v. Cut lacerations: Sometimes, a heavy sharp edged
weapon causes a deep and wide cut over the body
tissues.
Characteristics (Fig 11.7)
• Margins: Ragged, irregular and uneven; may show
tearing of the extremities at angles diverging from
the main laceration, the so-called 'shallow tails'; pieces
of tissue are attached in between called tissue tags or
bridges.
20
• Site: Occur most commonly over bony prominences,
such as the head where the skin is fixed and easily
stretched and torn.
Fig. 11.6: Avulsed lacerated wound
Duration Gross findings
Fresh Bleeding or fresh clot is attached;
margins are red, swollen and tender.
12-24 h 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 with soft reddish tender scar.
Few weeks Scar is whitish, firm and painless.
Fig. 11.7: Characteristics of lacerated wound
• Bruising and abrasion: Seen around the margin.
• Edges: May give an indication of direction in which
the blow or force was applied.
• Depth of wound: Shows bridges of irregularly torn
fibrous tissue, blood vessels and nerves across the
interior of the wound.
• Soiling of wound: Mud, wood splinters, sand, glass
fragments, paint material of the vehicle involved, hair
or fibres may get embedded in the wound and are of
great medico-legal importance.
• Hair bulbs: Crushed.
• Hemorrhage: Less, because the arteries are crushed
and torn across irregularly; they retract and blood
clots readily, except in the scalp where the temporal
arteries bleed freely as they are firmly bound and
unable to contract.
• Shape and size: May not correspond with the
weapon or object which produced them.
• Gaping: Seen due to pull of elastic and muscular
tissues.
• Beveling: Laceration caused by a blow directed
tangentially or at an angle will produce undermining
of the tissue on one side (indicates the direction of
blow) and abrasion and beveling on the other
(direction from which the blow was coming).
• On healing: Produces permanent scar.
Antemortem lacerations show bruising of margins, vital
reaction, eversion and gaping of margins.
Dating of Laceration
The gross findings is summarized is Table 11.3 when
healing occurs by first intention without any secondary
infection.
Complications
i. Lacerations may cause severe and fatal bleeding
leading to shock and death.
ii. Infection.
iii. Pulmonary/systemic fat embolism may occur due
to crushing of subcutaneous tissue.
Injuries 173
Table 11.3: Healing of a lacerated wound
iv. If located where skin stretches or is wrinkled, e.g.
over joints, repeated and continued oozing of tissue
fluids and blood may cause irritation, pain and
dysfunction.
Medico-legal Importance
• The type of laceration may indicate the cause of
injury and shape of blunt weapon, e.g.
i. Blunt round end (hammer) may cause a stellate
laceration.
ii. Blunt object with an edge, such as hammer head,
may cause crescentic laceration (patterned
laceration).
iii. Long, thin objects, like pipes or sticks produces
linear or elongated lacerations, while objects with
a flat surface produce irregular, ragged or Y-shaped
lacerations.
• Whether the laceration is accidental/homicidal/
suicidal?
a. Accidental laceration: Commonly seen anywhere
on exposed parts of body.
b. Homicidal laceration: Noticed on non-accessible
parts of the body, especially in assault cases. It is
usually seen on the head.
c. Suicidal lacerations are rarely seen, as they are
painful to produce and if present, they are seen on
exposed parts of body and on same side.
• Sometimes human bites can be a combination of
deep lacerations and crushing and are associated with
a high incidence of infection. It may be associated
with avulsion of pieces of the nose or ear. An
accidental type of injury results from an attacker
striking the victim's incisor teeth with his knuckles
(metacarpophalangeal joint is usually involved).
• Foreign matter in the wound could give clues about
the object causing it, e.g. paint material of vehicle
may be transferred to the lacerated wound.
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Fundamentals of Forensic Medicine and Toxicology
• Skin flap which overhangs the cut margin (avulsion
cases) can indicate the direction of force applied.
Wounds caused by sharp edged and pointed weapons are of four
types:
• Incised wound • Chop wound
• Stab wound • Therapeutic/diagnostic wound
Incised Wound (Cut/Slash/Slice)
Definition: Incision is a clean cut wound through the
tissues (usually the skin and subcutaneous tissues
including blood vessels), caused by a sharp-edged
instrument, which is more long than deep.
It is produced by pressure and friction against the
tissue by an object having a sharp cutting edge, such as
knife, razor or scalpel.
Characteristics21
• Margins: Edges are clean cut, well-defined and
usually everted. They may be inverted, if a thin layer
of muscle fibres is adherent to the skin as in the
scrotum (due to the attached dartos muscle to the
skin). The edges are free from contusions and
abrasions. Wrinkled wounds are produced where the
skin is wrinkled (i.e. folds) and more than one incised
wound is seen.
• Width/breadth: Width is greater than the edge of
the weapon causing it due to retraction of the divided
tissues.
• Length: Length is greater than its width and depth
and has no relation to the cutting edge of the weapon,
for it may be drawn to any distance.
• Shape: Usually spindle-shaped due to greater
retraction of the edges in the centre. Gaping is more,
if the underlying elastic fibres in the skin (Langer's
lines) have been cut transversely or obliquely and is
less when cut longitudinally (Fig. 11.8).
• Depth and direction: Usually deeper at the
commencement, except in case of suicidal cut throat
injuries, with hesitation cuts at the beginning. This
is known as head of the wound. Towards termination,
the cut becomes progressively shallow, known as
tailing of the wound (Fig. 11.8). Consequently, depth
of the incised wound with tailing will suggest the
direction in which the force was applied.
• Hemorrhage: As vessels are cut clean, hemorrhage
is more.
• Beveled cuts: If the blade of the weapon enters
obliquely, tissues will be visible at one margin and
Fig. 11.8: Incised wound
Fig. 11.9: Incised wound due to oblique strike
other margin will be undermined; if the blade is
nearly horizontal a flap wound is caused (Fig. 11.9).
Bevel: A surface having a sloped or slanting edge. It is the
angle or inclination of a line or surface that meets another
at any angle but 90°.
Dating of Incised Wound
Refer to Table 11.4 for dating of incised wound.
Medico-legal importance
• Indicate the nature of weapon (sharp-edged).
• Give an idea about the direction of force.
• Age of injury can be determined.
• Position and character of wound may indicate
manner of production, i.e. suicide, accident, or
homicide (Diff. 11.4 and refer to Fig. 12.22).
i. Suicide: Multiple incised wounds of varying
depths on the neck or wrists suggest a suicide.
Some features of suicidal wounds are:
a. Fatal wounds are present over limited accessible
areas of the body, such as front of neck, groin,
Injuries 175
Table 11.4: Dating of incised wound
Duration Gross findings Microscopic findings
Fresh Red with clotted blood Capillary dilatation, margination and emigration of
neutrophils, reactive changes in tissue histiocytes
12 h Margins red, swollen and adherent with blood and lymph
Reactive changes in fibroblast, monocytes in exudates
24 h Continuous layer of endothelial cells cover the surface with a scab of dried clot Endothelium begins to grow at edges, vascular buds
begin to form
2-3 days __ Vascularized granulation tissue formation (fibroblasts)
4-6 days __ Formation of new fibrils
7 days Scar formation Scar formation
Differentiation 11.4: Suicidal and homicidal cut-throat wounds
S.No. Feature Suicidal cut-throat Homicidal cut-throat
- Situation Left side of the neck and passing across the front of the throat
Usually on the sides
- Level High, above the thyroid cartilage Low, on or below the thyroid cartilage
- Direction Obliquely, above downwards and from left to right in right handed persons
Transverse or from below upwards
- Number of wounds Multiple, may be 20-30, superficial, parallel and merged with main wound
Multiple, cross each other at a deep level
- Edges Usually ragged due to overlapping of multiple superficial incisions
Sharp and clean cut, beveling may be seen
- Hesitation cuts Present Absent
- Tailing Present Absent
- Severity Less severe, one wound is severe, but sometimes, there may be 2-3 More severe, all tissues including vertebrae may
be cut
- Wounds in other parts of body Often present across wrists, groin and thighs No wounds on wrists, but severe injuries on
head and neck
- Defense wounds Absent, unintentional cuts may be found Present, unless taken unaware
- Hands Weapons may be firmly grasped due to cadaveric spasm
Fragments of clothing or hair may be grasped
- Weapon at site Usually present Usually absent
- Vessels As head is thrown back, carotid artery escapes injury Jugular vein and carotid artery are likely to be
cut
- Clothes Not cut or damaged May be cut, corresponding to injuries in the body
- Circumstantial evidence note
Quiet place, such as bed room; suicidal Disturbance at scene, footprints outside
chest or back of legs. Cutting of wrist is rarely
fatal. Suiciders usually do not injure the face.
b. Hesitation cuts/marks or tentative cuts or trial
wound: These cuts are multiple, small and
superficial often involving only the skin and are
seen at the beginning of the incised wound,
presumably hesitating while gaining courage to
make a final decisive cut.22
c. A person who commits suicide exposes his body
by opening his clothes and then inflicts the
wounds.
d. When a safety razor blade is used, unintentional
cuts are found on the fingers where the blade
has been gripped.
e. Most people have a vague knowledge of the
anatomy and do not know where to cut a major
176
Fundamentals of Forensic Medicine and Toxicology
blood vessel and may cut their forearms
vertically, rather than horizontally.
ii. Homicidal wounds: They are deep and deliberate
in character and are seen on the head, throat and
neck and sometimes on the trunk. Incised wounds
on nose, ears and genitals are usually homicidal
and may result from sexual jealousy, caused by a
jilted lover, husband or wife.23
iii. Accidental wounds: Commonly seen around the
hands.
iv. Defense wounds: Injuries are seen on the forearm
and palm, when the victim may try to ward off on
attack by raising hands and arms in defense or by
grabbing the weapon.
v. Self-mutilation: Sometimes, injuries may be caused
by an individual with a mental disorder as a form
of self-mutilation or by one who deliberately harms
oneself for motives of gain. They are found
anywhere on the body; superficial, multiple and
avoiding vital areas such as lips, nose and ears.
Chop Wounds
Definition: Deep gaping wounds caused by a blow
with the moderately sharp cutting edge of a heavy
weapon, applied with a significant degree of force.
• A chop wound is best considered a combination of
blunt and sharp force injury.
• Weapons used: Hatchet, axe, tomahawk, saber and
meat cleavers.
• Presence of an incised wound on the skin with an
underlying comminuted fracture or deep groove in
the bone indicates wounds caused by such weapons.
• Dimensions of the wound correspond to cross-section
of the penetrating blade.
• Margins are sharp, and may show abrasion, bruising
and some laceration with severe injury to the
underlying organs.
• Usually the lower end (heel) of the axe strikes the
surface first which produces a deeper wound than
the upper (toe) end. Deeper end indicates the position
of the assailant (Fig. 11.10).
• Undermining occurs in the direction towards which
the chop is made. In the skull, the undermined edge
of the fracture is the direction in which the force
was exerted and slanted edge is the side from which
the force was directed.
Medico-legal Importance
• Most of the injuries are homicidal and usually
inflicted on the exposed portions of the body, like
head, face, neck, shoulders and extremities.
Fig. 11.10: Determining the relative position
of the assailant from a chop wound
• Few are accidental due to machinery, like propeller
injuries.
• Rarely, they could be suicidal.
• Wound examination could reveal clues regarding the
causative weapon.
Stab Wound
Definition: Wound produced from penetration with
long narrow instruments having pointed (sometimes
blunt) ends into the depths of the body. Stab wounds
are deeper than its length and width.
• Word 'stab' means 'to wound or pierce with a pointed
weapon'.
• Weapons used: The most frequently used object is
a knife (single-edged kitchen or pocket knives with
a blade length of 10-13 cm). Less often, injuries are
caused by pieces of glass (broken-off bottle necks),
scissors, dagger, screwdrivers, pens, ice picks or
forks.
• A stab/punctured wound is an open injury in which
foreign material and organisms are likely to be
carried deep into the underlying tissues.
• Concealed punctured wounds: These are punctured
wounds caused on concealed parts of body, such as
nostrils, fontanelles, inner canthus of eyes, axilla,
vagina, rectum and the nape of the neck. They are
caused by slender instruments, such as ice picks or
knives with thin blades. Fatal penetrating injuries
can be caused without leaving any easily visible
external marks or bleeding.
Classification
Clinically, stab wounds are of two types (Fig. 11.11):
i. Penetrating wound: Weapon enters into the body
cavity producing only one wound, i.e. wound of
entry.
ii. Perforating wound (through and through
punctured around): Weapon after entering into one
side of the body will come out through the other
side, producing two wounds:
• 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.
Characteristics
• Margins: Edges of the wound are clean cut, usually
no abrasion or bruising of the margins, but in full
penetration of the blade, a patterned abrasion or
bruising may be produced by the hilt-guard striking
the skin. They are regular, sharp and well-defined.
However, injuries caused by a pointed or conical
instrument have lacerated edges.
• Length: Length is slightly less than the width of the
weapon because of stretching of the skin. For
measuring the length of stab wound, the edges of
the wound should be approximated.
• Breadth: It is more than thickness of the blade due
to gaping. Approximation of the edges is needed to
get the actual measurement.
Fig. 11.11: Classification of stab wounds
Injuries 177
• Depth: Depth is the greatest dimension of a stab
wound. Depth corresponds to the length of the blade
of the weapon entering the body, when the whole
length of the weapon enters the body, but has not
produced any wound of exit.
– It is not safe to find out the depth of a stab wound
by introducing a probe because it may disturb a
loose clot and may lead to fatal hemorrhage.
– The probe may easily pass between the fascial
planes or within the muscle producing a false
track. Depth should be determined in the OT,
when the wound is repaired.
Depth of stab wound depends on:
• Condition of the knife: Sharpness of the tip of the knife is
the most important factor in skin penetration. Once the
tip has perforated the skin, the cutting edge is of little
importance.
• Resistance offered by the tissues and organs: Apart from bone
and calcified cartilage, the skin is most resistant to knife
penetration.
• Clothing: Multiple layers of tough cloth or leather jackets
require greater force to penetrate.
• Force applied: Speed of thrust of the knife.
• Location: Stretched skin is easier to penetrate than lax
skin, e.g. chest wall.
• Angle of strike: A knife striking the skin at a right angle
penetrates more deeply, than when it strikes from some
acute angle.
• Direction: When a knife penetrates at an angle, the
wound will have a beveled margin on one side with
undermining (undercut) on the other, so that subcu-
taneous tissue is visible, indicating the direction from
which the knife entered (Fig. 11.12). In solid organs,
like liver, the track made by the weapon is seen well.
• Shape: It is slit-shaped with two acute angles or gape
open depending on their location and their
orientation, with regard to the cleavage lines of
Langer (Figs 11.13 to 11.15).
– A stab wound which runs parallel to the cleavage
lines will remain slit-shaped and narrow, and the
dimensions of the blade will be represented with
considerable accuracy.
– A stab wound which enters through the cleavage
lines transversely will gape.
i. If a single-edged weapon is used, the surface
wound will be triangular or wedge-shaped and
one angle of the wound will be sharp the other
rounded, blunt or squared off. Blunt end of the
wound may have small splits in the skin, so-called
'fish-tailing'. Virtually all stab wounds are made with
178
Fig. 11.12: Beveling of a wound
in case of tangential entry of a weapon
Fig. 11.13: Parts of a single-edged knife (one edge sharp
and the other blunt)
Fig. 11.14: Shape of stab wounds
Fundamentals of Forensic Medicine and Toxicology
single-edged weapons. Sometimes, this is not always
the case, as the blunt edge of the knife may split
the skin and resemble a double-edged knife
wound.
ii. If a double-edged weapon is used, the wound will
be elliptical or slit-like and both angles will be
sharp or pointed.
iii. A round object, like a spear may produce a circular
wound.
iv. A pointed square weapon may produce a cross-
shaped injury, each of the four edges tearing their
way through the tissues (stellate shaped).
v. Stabs produced with a broken bottle appear as
clusters of wounds of different sizes, shapes and
depths with irregular margins.
vi. A screwdriver will produce a slit-like stab wound
with squared ends and abraded margins.
vii. Skin wound made by closed scissors produce a
flat 'Z' shaped wound. If the blades were open,
the injuries may look similar to those produced by
a knife.
viii. Ice picks produce small, round or slit-like wounds
which may look like 0.22-calibre bullets or shotgun
pellets.
ix. A fork will produce clusters of 2-3 wounds
depending on the number of prongs on the fork.
• The pattern of arrangement of the dense network of
intimately intermingled dermal collagen and elastic fibres
is called the cleavage direction or lines of cleavage of the
skin and their linear representation on the skin are called
Langer's lines (Fig. 11.15).
• Skin tension and Langer’s lines may transform round
skin defects into slit-like wound resembling stabs
wounds; round-out genuine stab wounds and
artefactually lengthen stab wounds.
• The same weapon may cause apparently different injuries
because of their different locations and orientations of
the body due to skin elasticity (and Langer lines).
Complications/Cause of Death
i. Hemorrhage leading to hypovolumeic shock due
to injuries of major vessels (most frequent cause).
ii. Cardiac tamponade (less common).
iii. Aspiration of blood and air embolism—when the
stab is located on the neck (injury to jugular vein).
iv. Infections, because of foreign matter embedded in
the wound.
v. Asphyxia.
vi. Pneumothorax.
Fig. 11.15: Cleavage lines of Langer (similar
lines are present at the back also)
Medico-legal Importance
• Shape of the wound may indicate the type of weapon
which may have caused the injury.
• Depth of the wound will indicate the force of
penetration.
• Direction and dimensions of the wound indicate the
relative positions of the assailant and the victim.
• Age of injury can be determined.
• If a broken fragment of weapon is found, it will
identify the weapon or will connect an accused
person with the crime.
• Position, number and direction of wounds may
indicate manner of production i.e. suicide, accident
or homicide.
i. Suicide: Signs indicative of suicide:
• Location: Accessible areas • Tentative/hesitation
(precordial region— wounds: Concomitant,
most common site) shallow stabs with
• Direction: Descending, similar direction
backwards and to • Combination with trial
the right cuts (mostly on the
• Depth: Variable, mostly arms/wrists)
superficial and one enters • Exposure/undressing
the heart/pericardium of stab region
• Extensive traces of blood • Absence of defense
on the hands of the victim injuries
Death is due to hemopericardium if heart is involved,
but cardiac tamponade can occur (accumulation >
150 ml of blood is fatal).
Injuries 179
ii. Homicide
• Most deaths from stab wounds are homicidal,
especially if found in an inaccessible area, such as
back (most common mode of homicide in UK).
• Stabs are most often located on the thorax and the
neck.
• Stab wound of the chest may have any direction,
but the most common direction is at an angle from
left to right and from above downwards.
• The absence of weapon at the scene of incident
suggests homicide as the assailant usually does
not leave the weapon at the scene of death.
• The number of stabs shows a correlation with
gender of the perpetrator. In homicide committed
by female perpetrators, the victims had fewer stab
wounds on an average than in homicides
committed by male perpetrators.
The term ‘overkill’ refers to the infliction of massive
injuries by a perpetrator by exceeding the extent necessary
to kill the victim. Personal conflict between the
perpetrator and the victim, history of sex or drugs are
associated factors.
iii. Accident: Rare. It is caused by falling against any
projecting sharp objects, like glass or nails.
• Physical activity following fatal stab wound: Whether a victim
after receiving fatal stab can perform any physical activity,
like running away from the assailant or shouting for
help depends on the organs injured, extent of the injury,
the amount and rapidity of blood lost. When bleeding is
profuse, physical activity is limited and with slow
bleeding, the victim may be able to run a few meters
from the assailant.
– After stab injuries to the heart, the ability to act is
maintained at least for a short period of time.
– In lesion of the abdominal aorta, the ability to act
may be maintained over prolonged periods of time,
whereas in injuries of the thoracic aorta, incapacitation
generally occurs within seconds.
– Injuries of the lungs or abdominal organs do not lead
to immediate incapacitation.
• The amount of blood loss necessary to cause death is
variable from seconds to hours and depends on the rate
of bleeding, amount of blood loss, nature of the injury
and body’s physiological response.
– Arterial hemorrhages from major vessels may lead to
death relatively fast. A loss of > 1 litre of blood from
a major vessel may be fatal.
– Sudden blood loss causes interference with activity
when it exceeds 20-25% of the total blood supply. A
person can lose over a third of his blood volume before
progressing to irreversible hemorrhagic shock.
180
Fundamentals of Forensic Medicine and Toxicology
– A person who is elderly or frail has little reserve to
withstand blood loss may succumb quickly.
• Hara-Kiri (seppuku): It is an unusual type of suicide
connected with Japanese Samurai warriors in which the
victim with a short sword inflicts a single large abdominal
stab wound into the left side, drawing the blade across
to the right side and then turning it upwards producing
an L-shaped cut. The sudden evisceration of the internal
organs causes immediate decrease of intra-abdominal
pressure and cardiac return resulting in collapse and
death.
Defense Wounds
Defense wounds are wounds of the extremities which
result from the immediate and instinctive reaction of
the victim to ward off an attack.
They are usually classified into two types (Fig. 11.16):
i. Active defense injuries: They are seen when the
victim tries to seize the weapon and the injuries
are sustained on grasping the weapon. Injuries are
usually located on the palms, the flexor sides of
the fingers and the interdigital spaces, more
common in the web between the base of the thumb
and index finger (Fig. 11.17).
ii. Passive defense injuries: These are seen when the
victim raises the hands or arms for protection. They
are located on the extensor or ulnar surfaces of
forearms, wrists, knuckles and the back of the
hands.
• If the weapon is blunt, bruises and abrasions are
produced.
• If the weapon is sharp, the injuries will depend upon
the type of attack, whether stabbing or cutting.
i. In stabbing with single-edged weapon, if the
weapon is grasped, a single cut is produced on the
palm of the hand or on the bends of fingers.
ii. If weapon is double-edged, cuts are produced on
the palm and fingers.
iii. Cuts are usually irregular and ragged because skin
tension is loosened by gripping of the knife.
Fig. 11.17: Typical defense wound in a victim
with a sharp edged weapon
Defense wounds are absent if the victim is:
• Unconscious
• Taken by surprise
• Attacked from behind
• Under the influence of alcohol/drugs
Therapeutic or Diagnostic Wounds
These are produced by medical personnel during the
treatment of the patient, e.g. surgical wounds on the
chest and abdomen for insertion of tubes for drainage,
laparotomy incisions, cutdowns on antecubital fossa or
wrists, tracheotomy and thoracotomy incisions.
Sometime, they may be mistaken for primary traumatic
injury, e.g. chest tube drainage wound may be mistaken
for a homicidal stab wound.
To avoid misinterpretation, therapeutic tubing should
never be removed prior to sending the body for
postmortem examination.
Fabricated Wounds (Fictitious/Forged Wounds)
Fig. 11.16: Mechanism of defence wounds
Definition: Fabricated wounds are produced by a
person on his own body or by another with his consent.
It can be:
i. Self-inflicted wounds are those inflicted by a
person on his own body. Self-inflicted injury
without conscious suicidal intent is a form of self-
mutilation.
ii. Self-suffered wounds are those inflicted by
another person on the alleged victim.
Motive: The reasons for fabricating injuries are:
i. To simulate a criminal offence for false charge
• By women, to bring a charge of rape.
Injuries 181
• Charge an enemy with assault or attempted
murder.
• Convert simple injury into grievous one.
• By prisoners, to bring a charge of beating against
officers.
ii. To avert suspicion
• Destroy evidence of certain injury which might
connect a person with crime.
• Assailant may pretend self-defense.
• Policemen/watchmen may feign robbery or alleged
attack.
iii. By soldiers and prisoners to escape difficult task
iv. Suicidal gestures, attempted suicide
v. For the purpose of insurance frauds
Diagnosis: The diagnosis can be done by careful history
taking and examination of injuries (Box 11.1).
• Types of wound: Mostly incised wounds, sometimes
contusions, stab wounds and burns. Lacerated
wounds are rarely fabricated. Burns are superficial
and usually seen on left upper arm.
• Most commonly used object is a knife. Razor, glass
piece, scissors and ice pick are some of the other
objects used.
• Body parts where found: Top of the head,
forehead, neck, outer side of left arm, front and
outer side of thighs and front of abdomen and
chest (Fig. 11.18).
Box 11.1: Typical features of fabricated injuries
(Fig. 11.18)
• History of assault incompatible with injuries
• Multiple shallow, non-penetrating cuts or fingernail
abrasions
• Uniform in shape, linear or slightly curved course of
lesions
• Grouped and/or parallel and/or criss-cross
arrangement
• Location is easily reachable—usually on the left side
(non-dominant side)
• Avoidance of pain sensitive regions of the body
• Absence of defense injuries
• No damage to clothes or inconsistent damage