Microsoft Word Wounds corrected

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Wounds
It is the damage caused to any part of the body
by the application of

Definition
violence. Classification of wounds
Legal classification -
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a- Simple wound heals within 20 days. b-
Dangerous wound heals in more than 20 days (may
be associated with permanent infirmity) c-
Fatal wound leads to death.
Medicolegal classification -
2
According to the causative instrument

Wounds caused by blunt instruments
-
a
- Abrasions. - Bruises - Lacerations.

Wounds caused by sharp instruments
- b
- Incised wounds. - Stab wounds.
Wounds caused by firearm weapons -
c
- Firearm wound.
Wounds caused by physical and chemical agents
- d - Burns. - Corrosion. - Radiation and
electric burns.
Abrasions
-
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epidermis and may be the
It is superficial injury to the skin including
the

Definition
superficial layers of the dermis that may be
associated with minimal bleeding. Causative
instruments - pointed instrument - blunt
instrument with rough surface.
Types of abrasion
. a pointed instrument on the skin caused by
linear movement of

Linear abrasions
-
1
.
Scratches
. g.e
2
2- Brush abrasion caused by tangential impact of
a blunt instrument with rough
Grazing or Sliding abrasions
. g.
e
.
the skin
surface against
3- Crush abrasion caused by vertical impact of a
blunt instrument with rough surface to the skin
(it takes the pattern of the causative
instrument) e.g. bite abrasion, rope mark
abrasion and impact abrasion as in collision
against the front of the car that leaves
abrasion taking the shape of the car radiator.
4- Finger nails abrasion a- Linear fingernail
abrasion If the fingernail is dragged down the
skin. b- Semiluner fingernail abrasion If the
fingernail is applied on the skin with pressure.
c- Triangular fingernail abrasion I f the
fingernail is applied on the skin with higher
pressure. Medico legal importance of abrasion
1- It indicates violence. 2- Its shape gives an
idea about the causative instrument e.g. -
fingernail abrasions - Teeth abrasions
in bites. - Abrasions that take the
shape of the radiator in car accidents. 3- Its
site in the body may give an idea about the type
of the crime e.g. -Fingernail abrasions on the
neck suggest throttling - Fingernail abrasions
on the inner sides of the thighs suggest rape.
4-The age of the abrasion gives an idea about
the time of its infliction as follows - In the
first 2 days, it is covered with dry serum or a
soft scab. - A dry brown scab is formed after 3
days. - The scab falls after one week leaving a
red colored area which disappears after 3 weeks.
5- An abrasion may rarely cause death when it is
infected by tetanus or erysipelas. 6- Abrasions
differentiate cut wounds from contused wounds in
the areas where the skin is stretched over bone
(e.g. the skull). 7- Abrasion differentiates
hypostasis from bruises.

Bruises or contusions -
II
Extravascular collection of blood that have
leaked from blood vessels Definition damaged
by mechanical impact. The amount of force used is
less than the elasticity of the skin.
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tact epidermis but it is usually accompanied by
A pure bruise lies beneath an in

Note
abrasions.
. Heavy blunt instrument Causative instrument
Types of bruises According to the amount of
extravasated blood - Haematoma large bruise -
Ecchymosis Small bruise. - Petechial
hemorrhage the size of a pin head bruise .
Note Ecchymosis and petechiae are usually
caused by other than direct mechanical trauma
and are often seen on serous membranes and
conjunctiva as well as on skin. Factors
affecting the size of a bruise 1- Severity of
the blow rather than the size of the object. 2-
Onset of death bruises to the precordium may
lead to sudden death without any detected post
mortem bruises. 3- Blood diseases as hemophilia
or pupura (minimal blow results in severe
bruises). 4- Site a- vascular and lax areas
e.g. eye lids and labia major (minimal blow leads
to severe bruises). b- tough areas e.g. ( palm
and sole) show minimal bruises 6-Muscular bodies
bruise less than non- muscular ones. 7- Age
The 2 extremes of age bruise easily. 8- Sex
the females usually bruise easily than the males.
9- Effect of gravity - A bruise usually occurs
at the site of violence, but sometimes it may be
shifted downwards under the effect of gravity
e-g. a bruise at the forehead may sink down to
eye lid giving a black eye.

Medico legal importance of bruises
1- They indicate violence. 2- They give an idea
about the instrument used as they take its shape.
e.g. hammer, stick, etc. They are
longitudinal if caused by a stick . 2 parallel
lines of bruises are caused by a rubber stick 2
parallel lines of bruises going around the body
curvature are caused by whip. 2 curved rows ob
bruises in case of human bite
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2 parallel lines of bruises in case of animal
bite. Clusters of small discoid bruises of about
one cm in diameter are characteristic of finger
tip pressure. 3- Age of bruises can be compared
to the date of its infliction from the color
changes due to cellular infiltration and the
action of tissue enzymes - 1st day red in
color (oxy HB) - After 1-3 days blue (reduced
Hb). - After 2-5 days green (biliverdin) -
After 5-8 days yellow (bilirubin) - Bruises
fade away (heal) in 2-3 weeks. These color
changes start at the periphery and pass to the
center. 4- Bruises usually occur at the same
site of the blow but may gravitated downwards,
e.g. a blow to the calf gives bruises in the
heal. 5- Bruises differentiate cut from contused
wounds in skin stretched over bone (skull) 6-
Bruises must be differentiated from hypostasis.

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Differences between hypostasis and bruises
Bruises may be dangerous if - They occur in a
trigger zone. - They are extensive. - They
become infected - They hide a more serious
injury e.g. rupture organ.
ed wound Contus
-
III
It is a blunt injury in which the continuity of
the tissues is disrupted by

Definition
tearing rather than clean cutting. The force used
is more than the elasticity of skin. It is
usually associated with abrasions and bruises.
Causative instrument Heavy blunt instrument

Characters
1- Irregular edge with no angles (except in areas
where the skin is stretched over bone). 2-
Abrasions and contusions are usually present at
the edges. 3- The hairs are crushed or
irregularly cut. 4- The base is compressed with
bridging of tissues across the edges (e.g.
nerves, tendons). 5- Bleeding is minimal due
to crushing of the blood vessels.
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6- There is great liability to sepsis (due to
severe tissue destruction) 7- Healing is delayed
with a thick scar (2ry intention)
Incised wound - IV Definition These are
wounds caused by drawing a sharp instrument along
the skin. Causative instrument sharp edged
instrument e.g. knife, razor, piece of glass,
sharp axe etc.. Characters 1-The edges are
sharp and cleanly cut with acute angles
Irregular edges may be present if - The cut
occurs in areas with redundant skin. (Axilla,
scrotum, abdomen in obese persons). So that it
simulates contused wound. -The wound is caused
by moderately sharp instrument (e.g. the edge of
a broken glass) 2- The length of the wound is
usually longer than the depth. 3- Gaping of the
edges The amount of gaping depends on the
direction of muscle fibers ( if the cut is
across the direction of the fibers , gaping will
be great ). 4- The base is sharp and cleanly
cut. 5- Bleeding is profuse (cut vessels). 6-
Liability to sepsis is minimal (any contamination
will be washed by the profuse bleeding). 7-
Healing is rapid with thin scar (1st intention).
Medico legal importance It indicates violence
(except in surgical wounds) Gives an idea about
the causative instruments. Its age can be
determined to know the time of its infliction by
histological examination of the wound as
follows 30 minutes 4 hours Margination of
polymorphnuclear leucocytes in dilated small
vessels. 4 hours 12 hours - Leukocyte
infiltration - Tissue edema and swelling of
vascular endothelium occurs. 12-24 hours
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- Leucocytes tend to demarcate the area of the
wound by forming a marginal palisade (mostly
macrophage and mononuclear cells) - Mitosis in
fibroblast. Epidermis begins to spread across
the surface of the scab and down the sides of a
cut into the wound. - Budding of capillary
loops. 36 hours Complete capillary network
48 hours New vessels grow from the deeper
layers towards the surface. Pus may be present if
sepsis occurs. 5 days Obliteration of
vessels occurs. 10-15 days Complete healing by
primary intention if sepsis didn't occur. 3
weeks Red scar. 3 months Scar becomes
coppery 6 months Scar is thin and pale
sometimes it is even not detected.
Stab wound
-
V
Definition It is an incised wound that is
deeper than wide caused by forcing a pointed
sharp edged instrument inside the body by
thrust. Causative instrument 1- Knife -
Unibladed knife leaving a wound with an acute
angle. - Bibladed knife leaving a wound with 2
acute angles. (Elliptical). 2- Other knife like
weapons - Scissors, open razors and sharp tools
of many kinds like sharpened- screw drivers.
Characters 1- More deep than long 2- The
edges are sharply cut.
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3- Abrasions and contusions may be present on the
edges of the punctured wounds. 4- The shape of
the wound usually takes the shape of the
causative instrument a- A bibladed weapon
produces a wound with 2 acute angles. b- A
unibladed weapon produces a wound with one acute
angle while the other angle is rounded. c- A
closed scissor will produce a rhomboid wound. d-
A nail will produce a circular wound. 4- When
the weapon passes through solid structure e.g.
bone or cartilage, the wound produced will have
the same size and shape of the cross section of
the weapon. 5- The shape of the wound may be
changed if - The victim moves during the act of
stabbing. - The assailant moves the weapon while
he is dragging it out of the body of the
victim. 6- The length of the wound equals the
breadth of the weapon and a little smaller due
to retraction of the tissues unless the wound is
enlarged during withdrawal of the object. 7-
They are very dangerous due to internal injury,
hemorrhage and sepsis. 8- A broken tip of the
weapon may be found in the wound helping in the
identification of the weapon and the assailant.
Types of stab wounds 1- Ordinary stab wounds
are produced by pointed sharp edged instrument
e.g. knife or sword. 2-Punctured wounds are
produced by pointed end instrument, nail or
poker. 3- Penetrating wounds are stab or
punctured wounds which reach a body cavity as
pleural, peritoneal, dural or synovial cavities.
4- Transfixing wounds are stab or punctured
wounds which pass from one side of a limb to the
other side.
Fabricated wound
-
VI
These are self inflicted wounds to support a
false charge or to afford

Definition
suspicion from oneself. Causative instrument
usually sharp

Characters
1- They are parallel lines or incisions.
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2- The wound is usually superficial within the
reach of the person unless another person helps
him. 3- The tears in the clothes don't
correspond to those in the body. 4- Age of wound
doesn't coincide with the history given by the
person.

VII Defense wounds
Definition These are homicidal wounds sustained
by the victim during defending himself against
an attack by trying either to grasp the weapon by
hands or raise the arms towards off an attack to
protect the face and the head from injury. They
indicate violence 1- Injuries sustained by
grasping the weapon As in stabbing attacks
Grasping the knife produces cuts corresponding
with the position of the edges of the weapon.
Such injuries are usually found on the palms of
the hand and on the opposing bends of the
fingers or thumb. As grapping the knife will
loosen the skin tension the cuts produced are
usually irregular and ragged. 2- Injuries
sustained during raising the hand or arm towards
off an attack to protect his face and head They
may be in the form of cut wounds or contused
wounds or contusions according to the causative
instruments.

Complications of wounds
1- Neurogenic or primary shock. 2- Traumatic
shock (secondary shock). 3- Hemorrhage. 4-
Embolism 5- Infection. 6- Crush syndrome. 1-
Neurogenic or primary shock. It is a reflex
neurovascular disturbance which follows
immediately after an injury .It results from
A- Parasympathetic inhibition of the circulation
(vagal inhibition).or B- Sympathetico-adrinal
stimulation of the circulation.
) vagal inhibition (
the circulation
Parasympathetic inhibition of -
A
It results from - Severe emotions - Rise of
pressure in carotid sinuses.
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- Stimulation of trigger areas (epigastrium,
testis, larynx, cervix and urethra) as in the
following situations - Application of pressure
on the neck - Unexpected blows to the larynx,
chest, abdomen and genital organs. - Foreign
bodies in the air passages. - Cervical
dilatation. C/P
Bradycardia
-
- Sudden hypotension - Sweating - Nausea -
Vertigo - Pallor Usually death doesn't occur
because, ventricles escape the shock state as
they don't have vagal stimulation, however,
ventricular escape may not occur resulting in
rapid death from acute circulatory failure.

adrenal stimulation -
Symathetico
-
B
It results from - Severe pain. - Severe fright
-Anxiety - Tremor - Abdominal discomfort -
Sweating - Tachycardia - Hypertension
-Dilatation of pupil. If death occurs it
results from ventricular fibrillation
particularly if the patient suffers from
cardiac disease. 2- Traumatic shock (secondary
shock). It develops gradually after injury due
to reduction of total circulating blood volume,
with a secondary decline in venous return,
cardiac output and blood pressure. It occurs
due to
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release of histamine like substance from the
severely lacerated tissues that causes increase
in the capillary permeability and loss of
capillary tone, therefore a large
the
. (
number of capillaries are opened and dilated to
accommodate most of the blood
).
patient bleeds inside his own vessels
C/P Skin is pale cold and clammy with profuse
perspiration. Progressive prostration and
weakness with apathy and progressive depression.
Pupils are dilated.
) oligaemic shock
(
Hemorrhage
-
3
It is the most common cause of death in wounds.

Factors affecting the gravity of hemorrhage
mount of blood lost A-
a
The loss of 2 liters (one third of the total
blood volume) is dangerous to life.
Rate of hemorrhage - b Rapid loss of blood
is more serious.(sudden quick hemorrhage doesn't
allow for compensation leading to shock)

site of hemorrhage -
c
Internal hemorrhage is more serious than external
as it carries the risk of inducing pressure
over the organs e.g. -1/2 liter of blood in the
pleural or peritoneal cavities are fatal. -1/4
liter of blood in the pericardial sac is fatal.
Small intracranial hemorrhage is fatal (few cc
of blood in the brain substance is fatal.)

General condition of the patient -
d
Healthy adults can tolerate hemorrhage more than
children and old people. e- sex Females
tolerate hemorrhage than males.

Types of hemorrhage
Primary hemorrhage -
1
It is directly due to the wound, it is either
internal or external.
Secondary hemorrhage -
2
It is due to sepsis of the wound Æ dissolve the
blood clot by the lytic enzymes of the
organisms Æ patent blood vessels Æ bleeding It
occurs after a time of wound infliction (days,
weeks or months)

Reactionary hemorrhage -
3
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In this type of hemorrhage there is minimal
bleeding at the time of injury due to
associated shock state. Then, after a time
(about 10 hours) the person starts to bleed again
due to rise of blood pressure after recovery
from the shock stage that leads to dislodgement
of the blood clot that has been formed to close
the cut vessel.

P /
C
Rapid weak pulse Low blood pressure Subnormal
temperature Shallow rapid respiration Cold
clammy skin.
Embolism
-
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Types that have special medico legal importance
1- Air embolism a- venous air embolism
b- arterial air
embolism a- Venous air embolism

Causes
- Cut throat (cut jugular vein Æ -ve pressure)
- I.V. infusion. - Tubal insufflations. -
Criminal abortion. Fatal amount 100-200 cc.
Cause of death Air fills the right side of the
heart and pulmonary arteries Æ obstruction of
pulmonary circulation by frothy non-compressible
blood Æ acute heart failure. b- Arterial air
embolism Causes During artificial
pneumothorax, if the needle is passed in a
pulmonary vein. Stab transfixing wound
connecting a bronchus with a pulmonary vein.
Fatal amount few cc are fatal Cause of death
Occlusion of coronary and cerebral arteries.
3- Fat embolism Causes
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Fracture of a long bone with torn vein. Burns in
a fatty area Trauma to a fatty area. Cause of
death Acute heart failure due to obstruction of
the right side of the heart and pulmonary
artery with fats.

Thromboembolism

Causes
Prolonged recumbence in bed Cause of death
Prolonged recumbence in bed Æ deep vein
thrombosisÆ may be detached Æ.pulmonary
embolism after about 10 days of the injury or may
be earlier (2-3 days). 5- Infection. Contused
and lacerated wounds are the most liable to
severe infection particularly, tetanus and
gangrene due to devitalized tissue of the wounds.


Crush syndrome
-
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Severe crushing of muscles Æ liberation of
myoglobinÆ blocking of renal tubulesÆ acute
renal failure.