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The article will explain the
police and pathologist role in identification and examination of lacerations
and stab wounds, which are common and lead to demise, sometimes a very quick
one. Most of stab wounds are produced by pointed instruments. Majority of
them are homicidal. In stab wounds, the depth of the wound track in the body
exceeds its length in the skin. The edges of the wound in the skin are typically
sharp, without abrasion or contusion.
The typical weapons are knives, the most commonly used are:
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a flat-bladed knife,
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single-edged kitchen, pocket knife,
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folding knife with a 4- to 5-in. blade.
But not only knives are used, other devices, such as ice picks,
scissors, screwdrivers, broken glass, forks, pens, and pencils, have been used
to inflict stab wounds.
Once the tip has perforated the skin, the rest of the blade will slide
into the body with ease. As long as it does not contact bone, a knife can
readily pass through organs with very little force. Thus, even if a knife blade
is driven its complete length into the body, this does not necessarily mean
that the stab wound was inflicted with great force. Yet it is in most cases, lethal.
If the knife is not inserted all the way, the wound track is less than
the length of the blade. Whereas when the knife is be plunged deeply into the
body with such force as to indent the abdominal or chest wall, the length of
the knife track exceeds the length of the knife blade. If there are numerous
stab wounds in the body, one can usually get an approximation of the length and
the width of the knife blade by examining them all. The depth a stab wound
needs to achieve to produce a life threatening or fatal wound depends on the
area of the body stabbed.
The size and shape of a stab wound in the skin depends on the nature of
the blade and knife, as well as of the
following crucial indicators:
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the direction of the thrust,
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the movement of the blade in the wound,
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the movement of the individual stabbed,
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the state of relaxation or tension of the skin.
The sharpness of a weapon will determine the appearance of the margins
of the wound which are:
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sharp and regular;
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abraded and bruised,
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jagged and contused.
With a blunt cutting edge, the edges of the wound may be abraded. If an
individual is stabbed in a way that the flat surface of the knife blade is at
an oblique angle to the skin, the stab wound will have a beveled margin on one
side with undermining on the other, indicating the direction from which the
knife entered.
The shape of a stab wound in the skin is determined not only by the shape
of the blade, but by the properties of the skin. If a stab wound is inflicted
when the skin is stretched, the resulting long, thin wound will assume a
shorter, broader appearance when the skin relaxes. Langer’s lines can also
influence the appearance of a wound. Langer’s lines are a pattern of elastic
fibers in the dermis of the skin, which is approximately the same from
individual to individual. Plastic surgeons take advantage of this pattern of
fibers to conceal scars. If a double-edged weapon is used to stab an
individual, the wound will show bilateral pointed ends. If a single-edged
weapon is used, theoretically, one end of the stab wound is pointed and the
other is squared off or blunted. When actual wounds are examined, an obvious
fact indicates that a number of stab wounds caused by single-edged weapons have
bilateral pointed ends like those made with double-edged weapons. The most
common reason for a large, irregular knife wound is movement of the victim as
the weapon is withdrawn. The reason why it happens is due to the perpetrator’s
twisting the knife in the body after stabbing the individual. The ice picks are
no longer common household objects, ice pick wounds are rarely seen nowadays. Ice
picks produce small, round, or slit-like wounds that can be easily missed or
confused with wounds caused by .22-caliber bullets or shotgun pellets. This types
of wounds might be missed on a cursory examination of a body, especially if there
is little or no external bleeding. The fatal
and lethal wounds do not necessary may be given by sharp, big knives, there are
cases where fatal deaths were made by much more innocently looking objects. Bear
in mind if someone wants to kill someone, he/she does it without heavy
machinery.
Fatal stab wounds might be easily inflicted with
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pens,
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pencils,
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broken pool cues, etc.
In one case, an individual was stabbed on the left side of the neck with
a ballpoint pen. The pen perforated skin, muscle, and ligaments; penetrating
into the spinal column at the atlanto-occipital junction, and perforating the
spinal cord.
“(…)Unfortunately most fatal stab wounds with broken bottles are
homicides, occasionally suicides, and, rarely, accidents(…)”
Scarce but present accidents of fatal deaths caused by swords, arrows,
crossbow bolts are the incidents which are marked as stab wounds. The
appearance of the wound depends on the arrowhead. Target arrows have pointed
conical ends. They produce circular entrance wounds in the skin similar in
appearance to bullet wounds. Hunting arrows have from two to five knife-like
edges (four or five are the most common). The wounds produced are cross-like or
X-shaped with the four-edged arrowhead. The margins of the wound appear incised,
without abrasions. Thorough investigation
and examination of the murder weapon may uncover an unusual discovery,
therefore any blood or tissue present can be typed by DNA techniques to link
the weapon to the victim. It is possible for a knife or similar weapon to not
show microscopic blood staining after it has been used to stab an individual. In
stab wounds of solid organs, bleeding occurs only after the knife is withdrawn
because pressure of the knife in situ prevents bleeding. During
withdrawal of the knife, the muscular and elastic tissue of the solid organs
stabbed or the elastic tissue of the skin may contract about the knife and wipe
off the blood present on the blade of the knife. During its withdrawal from the
body, the knife may also be wiped clean by the clothing. If a knife appears to
be free of blood, the handles should be removed to see if any blood is there. With
folding knives, the recess for the blade should also be tested for blood. Rarely
a knife is found embedded in the body. To remove it, the thumb and index finger
should grasp the sides of the handle immediately adjacent to the skin. This
will help to avoid touching that portion of the knife handle that was in
contact with the assailant’s hand, where fingerprints may have been left. Most
deaths due to stab wounds are homicides. In such killings, multiple wounds are
usually widely scattered over the body. Most of the them often fail to
penetrate deeply and luckily they are not life threatening. Most
life-threatening wounds involve the chest and abdomen. Death is usually fairly
rapid due to exsanguination. The cases of suicide
are particularly difficult to handle due to multiple wounds and abrasions of
the victims. It takes victims so much
pain and effort to kill oneself – it is so sad to look at it. Those very
unhappy and broken people after continuous trying found a way and a mean to end
Ones life. According to the reports and data, most first suicidal attempts are
not successful, yet, it changes after second or the third time. Most suicidal stab wounds involve the mid and
left chest and are multiple in number, with many wounds showing minimal penetration
or just barely breaking the skin. The latter wounds are “hesitation” ones. Suicidal
stab wounds vary in size and depth with usually only one or two “final” stab
wounds going through the chest wall, into an internal organ. Occasionally, a
knife will be plunged into the body without any evidence of hesitancy.
Most fatal stab wounds are located in the left chest region due to the
fact that most people are right handed and, when facing a victim, will tend to
stab the left chest. In addition, if the intention is to kill someone, one
would stab in the left chest where the heart is. Most fatal stab wounds of the
chest involve injury to the heart or aorta. Deaths due solely to a stab wound
of the lung are less common. Fatal stab wounds of the right chest usually
involve injury to the right ventricle, aorta, or right atrium. Stab wounds of
the left chest usually injure the right ventricle when parasternal, and the
left ventricle as the stab wounds become more lateral and inferior. In cardiac
tamponade, once a victim acutely accumulates more than 150 mL of blood in the
pericardial sac, death can occur at any time. Stab wounds of the heart are
typically inflicted over the front of the chest, occasionally the sides, and
least commonly the back. The majority of the stab wounds of the left chest also
perforate the lungs. Some individuals survive stab wounds of the heart. Stab
wounds of the lower chest can produce injuries to not only the heart and lungs,
but also to the abdominal viscera. Fatal stab wounds of the abdomen usually
involve injury to the liver or a major blood vessel, e.g., the aorta, vena
cava, iliac, or mesenteric vessels. Occasionally, in wounds of the abdomen, death is not immediate.
One may say, „Oh My God! My Cellulite!”, in some cases – this thick
layer of fat saved One from immediate demise.
In a stab wound of the neck, the knife will sever not only a major blood
vessel, but also the trachea, with resultant massive hemorrhaging into the
pulmonary tree.
Victims of stab wounds of the brain have been hospitalized and the knife’s
entry into the brain not discovered because the wound was concealed by hair; in
the fold of the eye or under the eyelid. Death in such cases was due to either
continuing intracranial bleeding or infection. At autopsy the skull defect
produced by the weapon will match the width and thickness of the knife blade or
screwdriver or the diameter of an ice pick. Bleeding from a stab wound of the
brain may be subdural, subarachnoid, intracerebral, or a combination of all
three.
Is an individual is capable of physical activity, i.e., able to walk or
run away from the assailant after receiving a fatal stab wound? In come cases,
yes, One is capable, however, everything depends on the following factors:
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the organ(s) injured,
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the extent of the injury,
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the amount of blood lost,
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the rapidity with which the blood is lost.
With profuse bleeding, physical activity is limited or lost rapidly;
with slow bleeding, the victim is capable of walking away from the assailant. Not
infrequently, a trail of blood will mark the path of escape. Drainage from a
postmortem incised or stab wound is usually minimal due to the small quantity
of blood present in the severed blood vessel. However, should a large blood
vessel be severed after death and the vessel be located in a dependent area of
the body, the quantity of blood lost could be considerable. The dependent
position enables the network of blood vessels communicating with the severed
vessel to drain or “bleed” through the severed vascular wall. When a victim is
stabbed multiple times and bleeds heavily, the last stab wound inflicted may
appear bloodless. In such cases, the medical examiner may experience difficulty
in deciding whether this stab wound was inflicted before, during, or soon after
death.
Incised wounds of the neck can be accidental, homicidal, or suicidal. Accidental
wounds are extremely rare, usually seen only when an individual goes through a
sheet of glass or is struck in the neck by a flying fragment of glass or some
other sharp-edged projectile. In one case, a 13-year-old male was struck by
flying glass when a bottle containing dry ice exploded. The fragment of glass
severed his left jugular vein, causing exsanguination. Psychotic individuals
may use edged weapons to mutilate either themselves or others. Mutilation usually
involves the genitalia, ears, or nose. Non-psychotic individuals may mutilate
as a warning, in revenge, or to collect souvenirs (usually ears). Husbands
occasionally mutilate the genitalia of
cheating wives.
Chopping weapons cutting through bone can impart characteristic
striations on the bone unique to each type of weapon. Humphrey and Hutchinson evaluated
hacking trauma on bones produced by cleavers, machetes and axes. Hacking blows
produce wounds in bone characterized by at least one smooth, flat side with, in
the case of angled impacts, fracturing of the other side. Cleavers produce
clean, narrow wounds without fractures at the entry site; machetes wider,
less-clean wounds with small fragments of bone at the entry site and fractures
in the bed of the cut. Axes make crushing, fragmenting wounds with fractures. Microscopic
examination of these wounds by Tucker et al. found that cleavers produce thin,
fine striations that are sharp and distinct. Striations produced by machetes
were more pronounced but coarse and less distinct. Axe wounds showed no
striations on the bone.
Therapeutic or diagnostic wounds are produced by medical personnel during the
treatment of a patient. Common examples are thoracotomy incisions; surgical
stab wounds of the chest or abdomen for insertion of tubes and drains;
laparotomy incisions; incisions for peritoneal lavage; cutdowns of the wrists,
antecubital fossae, and ankles; and tracheostomy incisions. Some of these
surgical wounds may be mistaken for primary traumatic injury; e.g., a surgical
stab wound of the chest for a drain could be interpreted as a homicidal stab
wound. In other instances, the traumatic wounds are obliterated by the surgical
procedure; e.g., a stab wound of the left chest might be incorporated into a
thoracotomy incision. Occasionally, a homicidal stab wound is converted to a
therapeutic use, e.g., a surgical drain might be placed into the chest cavity
through a stab wound of the chest. If the individual dies and the drain tube is
left in the stab wound, the wound could be misinterpreted at autopsy.
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Acknowledgements:
The
Police Department;
https://www.politie.nl/mijnbuurt/politiebureaus/05/burgwallen.html and a Chief
Inspector – Mr. Erik Akerboom
©
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