Forensic slides all together.pdf

ABDOMINAL TRAUMA
Done by Abdullah abu shihab

Introduction :
1- lax and compressible abdominal wall
2- skin , fascia and muscle readily transmitted
the force to abdominal viscera
Abdominal organs are vulnerable to injury

Types of Abdominal Trauma
1.Blunt Trauma
-Child Abuse ( localized )
-Domestic Violence
- Iatrogenic injury ( CPR)
- RTA ( Generalized )
- industrial accident
2.Penetrating Trauma
-Stab
-Gun shot Injury

1- force
2- size of blunt object
3- condition of traumatize organ at impact
time ( splenomegaly , fatty liver )
4- gun shot Vs stap- injury
Severity of trauma depend on :

1- absent of external visible injury ( contusion ,
abrasion )
- protected by clothing
- Lax and compressible abdomen
2- Tranquilizer insensible for pain obscure sign
of peritoneal irritation
Many injuries may not manifest during the
initial assessment and treatment period

Case 1 :
21 yrs
- pain in lower region
with tenderness in
periumbalical area
-Normal vital sign
-normal investigation
28 hrs
Autopsy :
-2000 ml purulent material in peritoneal
cavity
-2*2 laceration in proximal jejunum
- 50 cm of duodenum ,
- communication with peritoneum
--3*5 contusion in mesentery and recent
thrombi in SMV

Must To Know
1- CPR : if misplaced  abdominal injury ( liver
laceration )
2- rectus sheath hematoma :
anticoagulant use  spontaneous rupture not
due to trauma  death

• soft ,compact vascular structures ( Liver and spleen)
- Laceration
- crushed
• distended hollow organs (Stomach and intestines) :
Burst due to increase intraluminal pressure
type of injury depend on the organ
involved

Liver
1- large size
2- anatomic position ( RUQ)
3- solid nature
• fatty disease of liver : more friable + coagulopathy
• Rt lobe * 5 > Lt lobe
It’s vulnerable to injury

• When the liver is propelled in an anterior-posterior direction, the retrohepatic vena
cava fixes the liver (empty arrow), and the liver lacerates along Cantlie’s line due to
the acceleration of the right lobe of the liver

Acceleration injury in the right lobe of the liver caused by blunt forces from a lateral
right direction. The right triangular ligament making segment VII relatively fixed and B)
while the anterior lobe continues to move violently

. When the blunt force pushes the left lobe of the liver toward the back, the
falciform ligament serves as a counterforce The section of the liver that bears the
shearing stress moves posteriorly and is lacerated.

• . When the upper right quadrant is under compression in an anterior-
posterior manner, the liver is crushed between the anterior and posterior
walls of the rib cage) which lacerates the posterior and anterior sides of
the liver at the same time.

SPLENIC INJURY
- 20% of splenic injuries due to left lower rib fractures
• splenomegaly ( increase fragility)  increase risk of
spntanuous rupture (malaria leukemia )
• Truama in LUQ :-
• laceration
• Sub capsular hematoma ( asymptomatic , vague abp)
• Rupture (hrs to days or form scar
• microscopic section

Pancreatic Injury
• Rare 10-20% of all abdominal injury due to
retroperitoneal location
• Crush
• Direct blow to abdomen
• Seat belt injury
• Associated with abdo. Duodenal injury, Vascular
injury & liver injury

Severe localize at the midepigastrum
• contusion
• Laceration ( bile duct injury  peritonitis)
• Transection

Esophagus
• Rare cause of death
• laceration ( transmural , mucosal )
-single number
- longtudinal
- Post. Lateral
** alcohol ( Mallory weiss )
-Mediastenal emphysema
- Bilateral hydrothorax
- hydropneumothorax
- Massive hemorrhage
Due to to repeat violent vomiting  increase pressure  perforation posteriolateral

Must to know
• after prolong Coma  agonal (
esophagiogastromalacia ) auto digestion of
lower esophagus and stomach
• grayish to black appearance with absence of
inflammation

Stomach
1-protected by rib cage
2- mobile segment ,displaced with trauma
3- partaily protected whent the compression effect relax the cardic
and pyloric sphinicter ( evacuate content !!)
ULQ and epigastric trauma
- Kick
- Fist
- *Psychological ( glass, hair )
**Contusion  necrosis  perforation
**Perforation ( anterior) peritonitis
Severity of injury
Stomach injury is uncommon

• Ragged echomotic edge with circular defect
More distended  more injury

Bowels
• Jeujenum> Ileum > Dudenum > stomach
Three mechanism of blunt injury :
1- crushing b/w Ant.Abdominal wall and Vertebral column
or pelvis
2- deacceleration at point of fixation ( ligament teritz)
3- increase intraluminal pressure

Duodenum (Sup,desc, horz,asc )
• Blunt injury in vicinity to ligament teritz
- Ascending an Duodenojujenal flexure
• fixed by L. teritz
• Overlies the vertebra L4
***Contusion  perforation( hrs –days) transaction
If duodenum was dilated during impact the
duodeno jejunal flexure affected

Jejunum and ileum
• Jejunum occupies umbilical and left ileac
region
• Ileum occupies umbilical , hypogtrium pelvis
and right ileac region
• Jejune ileum attach to posterior wall by
mesentery ( blood vessel and nerve )
1- contusion
2- perforation
3- Transection

• Transection of jejunum just distal to ligament
teritz ( fixed to Post . Abd) associated with
mesentery injury
• Severe blunt trauma  mesentery torn 
- single or multiple
- If large vessel lacerated ( bleeding )

Colon
• 1- larger in diameter
• 2- less vulnerable to injury
• 3-fixed in position
• Rupture due to insertion of foreign body
- Sexual stimulation

• Mid point of transverse
colon ( Vertebra posterior)
1- contusion
2- perforation
3- Transection

Renal Injury
• Clinically not suspected & frequently overlooked
• Mechanism: Blunt , Penetrating
Crush abdominal
Pelvic injury
Direct blow to flank or back
Fall
MVA

-Contusion
-Transverse laceration under capsule with min bleeding
-Massive uncommon with other massive abdominal injury

Urinary bladder
• Empty in pelvis behind pupis symphisis
• Distended ascend to lower abdomen
- in children b/w umbilical and pupis symphysis
which descend in puberty
** urine content more distended more injury
• Extraperitoneal (laceration ) when empty
• Intrapertonial ( perforation ) when full

Internal genitalia
• non pregnant rare with pelvic fraction
• Pregnant uterus  fall ,RTA small
separation of placenta at the moment of
trauma  hematoma needs hrs to form and
kill the fetus  DIC (48 hrs )

🙢
Forensic Autopsy
Prepared by : Marwan Fayez Jomah

🙢
� Autopsy definition
� Academic autopsy vs. Forensic autopsy
� Examination of the scene of death
� Property, clothing and identification- things to look for
� risks and hazards in autopsy room
� External examination vs. Internal examination
� Ancillary investigations
� Autopsy Report
� Post-mortem artefacts
� Exhumation
� The autopsy on the putrefied corpse
� Resuscitation artefacts at autopsy
� Mass disasters
� The obscure autopsy
General Terms

🙢
� It is the examination of the body of a dead person.
� It begins with body examination and evidence
collection at the scene and proceeds through history,
physical examination, laboratory tests, and diagnosis
Definition

🙢
• The academic autopsy is performed by trained pathologists
with the written permission of the next of kin to :
1- determine the cause of death.
2- the extent of natural disease.
3- the combination of comorbidities that led to the person’s death.
4- Effect of partial therapy on the disease coarse
5- uncover previously unrecognized disease
6- provide information on how the disease led to death
• Focus is more on the internal examination
• Considered as a medical education tool ; e.g.: research purpose
Academic autopsy

🙢
� Application of medical science to answer a legal
matter.
� External & internal examinations are both important
� Purpose : is to know the cause and manner of death
for people dying sudden, unexpected, violent, drug-
related, or otherwise suspicious deaths.
Forensic autopsy

🙢
� Cause of death : The exact event that led to anatomic
and physiologic derangement that led to individual’s
demise.
� Mechanism of death: is the physiological
derangement produced by the cause of death that
results in death.
� The manner of death: explains how the cause of
death came about.
Forensic autopsy

🙢
� Manner of death Categories:
1- Natural death
2- Accidental
3- Homicide
4- Suicide
5- Undetermined ; death in abstentia
Forensic autopsy

🙢
� The objectives of an autopsy :
� 1. To determine the cause of death .
� 2. To determine the mode of dying and time of death
, where necessary and possible .
� 3. To demonstrate all external and internal
abnormalities, malformations and diseases .
� 4. To detect, describe and measure any external and
internal injuries .
Forensic autopsy

🙢
� 5. To obtain samples for analysis, microbiological
and histological examination, and any other
necessary investigations .
� 6. To provide a full written report of the autopsy
findings
Forensic autopsy

🙢
Examination of the scene of
death

🙢
- The pathologist should observe a great deal, but do
very little .
- Any obvious cause of death should be observed, and
any blood pools or splashes noted in relation to the
position of the corpse.
- Close examination can be made and the skin felt to
assess temperature. The eyes, neck and hands can be
examined and where necessary, clothing gently
moved aside to look at the throat or upper chest.
Any relevant findings should be photographed by
the police before further disturbance .
Things to observe

🙢
� contents of the pockets
� Documents
� Empty drug or poison containers
� Other helpful artifacts such as hearing aids,
� syringes, external pacemakers and inhalers
� Clothing properties
Property, clothing and
identification- things to look for

🙢
� The use of the history of the deceased ‘patient’ or
victim is a vital and indispensable part of the
investigation
� The identification of body is important before
starting examination includes:
1) labeling the body as soon as it arrives in the
mortuary.
2) Photographing the body with a serial number.

🙢
1. infection
2. physical risks ( sharp instruments, bone fragment,
toxic chemicals or radioactive materials )
3. injuries (resulting from lifting heavy loads ,slipping
or falling )
� All these can be minimized by awareness,
appropriate design of the facility, adoption of safe
working practices, proper supervision and
management.
risks and hazards in autopsy
room

🙢
� Body is weighed, measured and X-rayed
� Photographs are taken of the body (front, back & naked)
� Fingerprints are taken (if any missing parts are noted)
� Scrape underneath fingernails for evidence
� Examination of clothes
� Age, sex and race are noted
� Eye color, scars, tattoos are noted
� Examination of the eyes (blood spots & etc.)
� Any body secretions and gun powder residue/ bullet holes
� Body fluids are drawn from the body for testing (blood, urine,
spinal fluid, vitreous humor from the eye
� Body is cleaned and ready to be put on table.
� Sexual assault specimens
Autopsy – External
Examination

🙢
� Put a “body block” under the back 🡪 maximum exposure of trunk.
� Incision is made : Y-shaped , T-shaped or vertical incision.
� Chest cavity is opened via shears
� Inspection at organs inside the body for evidence of injury
2. Removal of organs
1. Letulle’s “En Masse” method – All organs at once
2. Ghon’s “En Bloc” method – Organs removed in
sections
� organs then should be weighed and sliced
� allows for the collection of specimens for toxicology such as heart blood,
gastric contents, bile, and urine, as well as samples of solid organs that
may prove useful in the toxicological analysis of certain cases.
Autopsy – Internal
Examination

🙢
A. Microbiology.
� Cultures : Spleen, Heart, Lung.
� Bacteria in Post mortem +ve cultures by four mechanisms:
1) Invasion during life.
2) agonal spread i.e. bacterial invasion during the dying process or
during artificial maintenance of circulation and respiration at
resuscitation.
3) post-mortem translocation due to migration from the mucosal
surface into the blood and body tissues.
4) through contamination where bacteria are introduced into the
blood, CSF or tissues during sampling.
Ancillary investigations

🙢
B. Toxicology (Blood, urine, stomach contents, organs
(especially liver), intestinal contents, CSF, bile and
ocular fluid may be required.)
C. Histology (timing, vitality and causes of injuries or
identification of the nature of aspirated or ingested
material found in the airways or gut.)
Ancillary investigations

🙢
� The autopsy report should be a clear, concise, easy-to read, and
well-organized document that accurately states factual
information collected at autopsy.
� Contains:
1- External examination
2- Evidence of therapy
3- Evidence of injury
4- Internal examination
5- Microscopic examination
6- Toxicology
7- Summary of findings
8- Cause and manner of death
Autopsy Report

🙢
� The pancreas: Autolysis because of the proteolytic
enzymes within it .
� Patches of hemorrhage in the neck: leakage from the
venous plexuses .
� Stomach “Gastromalacia”.
� Heat fractures of the bones in victims of severe fire.
� Blood or bloody fluid issuing from the mouth.
� Dark red discoloration of the posterior part of the
myocardium: gravitational hypostasis
� Resuscitation artifacts
Post-mortem artefacts

🙢
� CPR
� Laryngoscope
� Puncture marks
� Electric defibrillator pads
� Subarachnoid hemorrhage after external cardiac
massage
Resuscitation artefacts at
autopsy

🙢
�Exhumation is the retrieval of a
previously buried body for post-
mortem examination.
Exhumation

🙢
� Decomposed bodies are common place, especially in
warm climates.
� No short cuts should be taken by the pathologist
merely because of the unpleasant nature of the
examination. However bad the condition of the
corpse, every effort should be made to carry out the
autopsy as near to the usual routine as possible
� The interior of the body is often far better preserved
than the outward.
The autopsy on the putrefied
corpse

🙢
� a commonly accepted definition is the death of more
than 12 victims in a single event.
� To retrieve and reconstruct bodies and fragmented
bodies decently.
� To establish personal identity.
� To conduct autopsies on some or all of those bodies.
� To establish the cause of death in some or all.
� To obtain material for toxicological analysis.
Mass disasters

🙢
� Several surveys in various countries have shown that
where a physician offers a cause of death without the
benefit of autopsy findings, the error rate is of the
order of 25–50 per cent, even in deaths in hospital.
Thus the value of an autopsy in improving the value
of death certificates is undoubted .
� Failure Rate 5%
� New vs experienced Pathologist
� More common in younger age group
� Example: 20 vs 60 years old
The obscure autopsy

🙢
ً
‫شكرا‬
‫لحسن‬
‫استماعكم‬

Blunt Force Injury
Prepared by: Younis Yasin
Supervised by: Dr. Rayan Al-Ali

• Injuries resulting from an impact with a dull, firm surface or object.
• Individual injuries may be patterned (e.g. ,characteristics of the wound
suggest a particular type of blunt object) or nonspecific.
• Mainly on external injuries, but blunt force trauma may cause contusions
and lacerations of the internal organs and soft tissues, as well as fractures
and dislocations of bony structures.
• Most common injuries documented or interpreted by forensic pathologist.

Abrasions
Contusions
Laceration
Skeletal
fractures
key manifestations

Severity, extent, and appearance of blunt trauma
injury depend on:
Subject dependent:
• Anatomical region being impacted
• Age of the individual
• Medical status
Object dependent:
• Type of instrument making contact with the body
• Body surface area impacted
• Amount of time it makes contact

External Examination
• Should be carefully documented
• The photography of injury should always include an overall picture and series
of macroscopic pictures to draw out necessary details
• A case number should always appear in autopsy photographs, and, where
applicable a ruler or other scale
• One must not blindly examine injuries for the purpose of autopsy report
description
• It is key that autopsy pathologist look for patterns or orientation of injury

• Abrasion occurs when the skin contacts an opposing surface and the
movement of either the skin or the surface results in friction that pulls away
the superficial layer(s) of skin .
• Antemortem abrasions have reddish brown appearance and heals without
scarring
• Abrasions produced after death are yellow and translucent with a
parchment- like appearance
• May be the only external evidence of trauma to the body
Abrasions

Case: The 40 year old woman was
ejected from her motor
vehicle when she crashed at
highway speed into a parked
car. She survived for 4 hours
in the hospital before dying of
a closed head injury. Note the
dark red-brown abrasions
over her left chin and cheek.
The reddish appearance of
this injury indicates an
antemortem origin with vital
reaction occurring in the
traumatized tissue.

A 25 year old man was witnessed to collapse and
die of a previously undiagnosed cardiac
abnormality. At the seen, a large round abrasion
was observed over the wright malar prominence.
As is typical of peri- and postmortem abrasions,
this had yellow-brown coloration and atexture
somewhat like parchment. There was no evidence
of a vital reaction. At autopsy, this same abrasion
had dried, was red-brown in color and mimicked
the appearance of the smaller more posterior,
antemortem abrasion.

Types of abrasions
Scrape or brush
abrasions
Impact abrasions
Patterned abrasions

Scrap (brush) abrasions
• The blunt object scrapes off the superficial layers of the skin, leaving a denuded
surface
• At times, these abrasions may be fairly deep, extending down to the dermis
• In such instances, there may be leakage of fluids from vessles with deposit of
serosanguineous fluid on surface of abrasions. This dries forming the familiar
reddish brown scab
• One of the most common types of scrap abrasions is the linear abrasion known
as a scratch
• Extensive scrap like abrasions (graze or sliding) are seen in pedstrains who
slide across the pavement after being hit by motor vehicle
• Particles of gravel, dirt ,or glass may be embedded in such wounds
• Similar scrap abrasions may be produced when a victim’ body is dragged over a
rough surface

Impact abrasions
• The blunt force is directed perpendicular to the skin, crushing it
• Tend to be focal, commonly seen over bony prominences where a thin layer of
skin covers the bone
• Impact abrasions over the supraorbital( eyebrow), zygomatic arch(cheeks),
and the side of the nose are commonly seen in individuals who are
unconscious when they collapse, and strike their heads on the ground.

Patterned abrasions
• Variation of an impact abrasion
• The imprint of either the offending object, such as a pipe, or intermediary
material, such as clothing, is imprinted or stamped on the skin by the
crushing effect of blunt object
• Not only the may the epidermis be damaged, but the skin may be compressed
into the cavities of the pattern with consequent capillary damage leading to
an internal bruise

Artifact!
• Postmortem diaper rash are occasionally misinterpreted as abrasions by the
inexperienced physician
• Another artifact, is the drying of the skin of the scrotum, less commonly, of
the vulva

Dating of abrasions
• The literature contains multiple different techniques or approaches to dating
of abrasion healing
• There is interpersonal variability in human physiology, underlying pathology,
and mechanisms of trauma
• Histological examination of abrasions in an attempt to determine their age is
possible to a degree
Stages of healing
• 1.Scab formation , indicating survival after injury (2-4 hrs) Reddish
• 2.Epithelial regeneration, arise in surviving hair follicles and margins of
abrasions (30-72 hrs) Reddish Brown
• 3.Subepithelial granulation and epithelial hyperplasia, after epithelial
covering of abrasions (9-12 days) Brownish black
• 4.Regression of epithelium and granulation tissue , epithelium becomes
remodeled, thinner, atrophic, prominent collagen fibers, decreased dermis
vascularity ( after day 12)

• A contusion or bruise is an area of hemorrhage into soft tissue due to rupture
of blood vessels caused by blunt trauma
• Contusions maybe present not only in skin, but also in internal organs such
as the lung, heart, brain, and muscle
• A contusion may be differentiated from an area of livor mortis in that, in a
contusion, blood has escaped into soft tissue and can’t be wiped or squeezed
out, as in area of livor mortis
• Contusions might reflect the configuration of the object used to produce the
contusion, that is, it might be patterned
Contusions

Absence of contusions or abrasions does not exclude
presence of blunt force injury !

Notes
• Senile purpura (ecchymoses ) on the forearm of elderly may be mistaken for
bruises
• Women, especially if obese, seem to bruise more easily
• Soft, lax, vascular tissue, such as in the eyelid, is more susceptible to bruising
than areas such as the palm
• Alcoholics with cirrhosis, individuals with bleeding diathesis , bleed more
easily
• In cases of basilar skull fracture, blood can dissect through facial plains,
creating the appearance of contusion

Dating of Contusions
• Methods used to age a bruise are histology and color changes
• Most common method used is change in color that a bruise undergoes as it
heals
• Yellow coloration is visible sooner in superficial bruises than in deep bruises
• Dark pigmentation may conceal a bruise
• Depth and location of a bruise can influence its time of appearance
• As a bruise ages, it undergoes an evolution in its color due to the degradation
of hemoglobin
• Unfortunately, rate of color change is quite variable
• All one could say about a bruise with yellow coloration is that its more than
18 hours old

Postmortem bruising
• Contusions can be produced postmortem if a severe blow is delivered to a
body within a few hours of death
• Blow can rupture capillaries, forcing blood into the soft tissue and producing
a postmortem contusion identical in appearance to antemortem one
• Rarely seen, commonly seen in skin and soft tissue overlying bony
prominence
• Microscopic examination to determine weather its antemortem or
postmortem is of no help

• A laceration is a tear in tissue caused by either a shearing or a crushing force
• One can have lacerations of internal organs as well as the skin
• Laceration of skin tend to be irregular with abraded contused margin
• As a general role, however, long, thin objects such as pipes tend to produce
linear lacerations , while objects with flat surfaces tend to produce irregular,
ragged, or Y shaped lacerations
• As contusions, determining the age of lacerations is difficult
Lacerations

• Lacerations occur most commonly over bony prominences, where the skin is
fixed and can more easily be stretched or torn
• Since different components of soft tissue have different strengths, there is
usually incomplete separation of the stronger elements, such as blood vessels
and nerve, so that when one looks at the depth of th laceration, one sees
“bridging “ of tissue running from side to side
• Presence of bridging proves decisively that one is not dealing with an incised
wound
• The depth of the laceration should be explored for the presence of foreign
material that could have been deposited there by the weapon

• If the blow or impact that causes a laceration is delivered at an angle, rather
than perpendicular to the surface of the body, one will find undermining of
tissue to one side, which indicates the direction that the blow was delivered
• The other side of the laceration, the side from which a blow was coming, will
be abraded and beveled

• In avulsion or avulsive injury, to the outside of a body is a form of laceration
where the force impacting the body does so at an obligue or tangenital angle
of the skin, ripping skin and soft tissue of the underlying fascia or bone
• Tires passing over an extremity may avulse soft tissue off the bone. In case of
extreme avulsion, an extremity or even the head can be torn off the body
• Internal organs can be avulsed or torn off from their attachments

• A variation of avulsion forces is one produced by shearing forces, where the
skin shows no signs of injury but the underlying soft tissue has been avulsed
from the underlying fascia or connective tissue, creating a pocket that can be
filled with a large quantity of blood
• This injury is usually encountered on the backs of the thighs of pedstrains
struck by motor vehicles
• As the hood of the car impacts the back of the thigh and lefts up pedstrains, it
imparts a shearing force to this groin, avulsing the skin and subcutaneous
tissue of the fascia creating pockets where blood can accumulate

Defense wounds due to blunt force
• One can have defense wounds from an attack with a blunt object
• There are generally abrasions, and contusions on the back of the hands,
wrists, forearms and arms
• Lacerations are less common and may contain embedded fragments of the
weapon in the wound

Determination of whether a wound is Ante- or
Postmortem
• Made by gross or microscopic examination of the wound
• The presence of bleeding into the tissue is presumed evidence that the
deceased was alive
• Microscopic examination of the injury in search of an inflammatory reaction
• The problem is that some tissues do not show an inflammatory reaction
unless the victim has survived for at least several hours after injury
• Analysis of enzyme activity in antemortem wounds has demonstrated a zone
of decreased enzyme activity at the center of the wound, with increased
enzyme activity at the periphery
• Enzyme activity can be detected up to 5 days after death
• Other markers, such as DNA, C3 factor, vasoactive amines, catecholamines
have been used

Fractures of the face
• Fractures of the mandible, maxilla, zygoma, and zygomatic arch are produced
predominenty by assaults, and motor vehicle accidents
• Maxillary fractures can be classified in five categories
1-Dentoalveolar
2-Lefort I
3-Lefort II
4-Lefort III
5-Sagittal

•Direct application of force
•Penetrating
•Crush
•Focal
•Indirect application of force
•Traction
•Rotational
•Angulation
•Compression
Fractures of extremities

• When a blunt object impacts along bone, it tends to bend the bone producing
disruption or cracking of the bone on the side opposite the impact side
• With significant impact, however, there is crushing on the side of the bone to
which the force is applied, prior to bone’s cracking

Pelvic Fractures
• An immense amount of force is required to disrupt the pelvic ring
• Because the pelvis is a ring, disruption of any portion of it is usually
associated with disruption of another portion of the ring
Classified by direction of force:
1. Anteriot-Posterior compression
2.Lateral compression
3. Shear
4.Complex fractures

DR: Rayan AL-Ali
Abdullah abu shihab

Chest injuries
Forensic anatomy
Damage to:
1) chest wall
2) viscera :
- from the forensic aspect,
the spleen most of the
liver stomach are thoracic
organs ,they lie largely
beneath the costal margin,
and are vulnerable to both
stabbing and blunt injury
to the chest.

Injuries to the chest wall
Respiration is
dependant on
Good
expanstion
Integrity of
the rigid chest
wall
Can be
compromised
by :
Penetrating of
pleural
cavities
Severe
mechanical
failure of the
rib cage

flail chest
**an injury of the thoracic cage with three or
more rib fractures in two or more places and
sometimes with
added fracture(s) of the sternum.
**Loss of rigidity of cage
Impaired the expansion during inspiration
Paradoxical respiration
Progressive hpoxiadyspneacyanosis
** The flail chest is caused by frontal violence:
1) motor vehicle accidents
2) stamping assaults

**In any substantial chest injury w broken rib ends may ripping the parietal
and visceral pleura penetration of the lungs & bronchopleural fistula
pneumothorax hemothorax.
**gross chest injuries external communication with the atmosphere
Pneumothorax. ( rare in civil practice,common in battle casualties) .
**falls onto the side rib fractures in the anterior or posterior axillary line.
**The upper ribs are less often fractured, except by direct violence from
kicking, heavy punching or traffic accidents.

ANTE-MORTEM FRACTURS: " during life" : The fracture sites almost always show
bleeding beneath the periosteum or the parietal pleura. (mostly)
POST-MORTEM FRACTURES: some may exhibit slight oozing from the marrow
cavity into the adjacent tissues.
CPR (PERIMORTAL) : is a common cause for extensive rib fractures " difficult to
differentiate in pathology the cause ( original trauma or enthusiastic first aid)“.
But in infant is rare (there ribs are very pliable ).
- it is often impossible to say if they were immediately ante-mortem or post-
mortem.
The bracing action of adjacent intercostal muscles may conceal any mobility of
the ribs slit all the intercostal muscles with a knife when chest injury is
suspected allow any mobility to be detected more easily.
In the osteoporosis of senility and some diseases the ribs may be breakable by
finger pressure.

Infant with rib fractures:
**may be an important diagnostic sign of child
abuse in doubtful cases.
**Fresh fractures may be difficult to detect on
routine skeletal radiology and even at autopsy
each rib should be investigated after stripping of
the pleura.
**Possible fractures should be confirmed
histologically also regarding the age of the injury.
**Within about 2 weeks (very variable), callus
form (visible both on X-ray and by direct post-
mortem inspection ( difficult to date callus).
hyperflexion of
chest anteriorly
The ribs are levered
against the
transverse
processes of the
vertebrae
break ribs in their
posterior segments,
usually near their
necks,
"paravertebral
gutter".

Hemorrhage and infection in the chest
Hemothorax is the presence of blood in the pleural space.
Sources of blood :
1) Any injury that breaches blood vessels and the pleural lining
(most massive H. : large vessels in lung or mediastunm),
intercostal and less often the mammary arteries.
2)The lung hilum can be torn or penetrated by stabs wounds.
3)heart itself,( must also be a defect in the pericardial sac before
the blood can reach the chest cavity).

*Death may occur from loss of circulating blood volume,
even if there is relatively little external bleeding.
* A knife that passes obliquely
into the chest through intercostal muscles may puncture
a great vessel or heart chamber, allowing a fatal cardiac
tamponade or haemothorax, yet the valve-like overlap
of the tissues after withdrawal of the blade may seal
up the external wound almost completely and prevent
significant bleeding

*Infection following a chest wound is uncommon
in forensic practice, as most deaths occur from
haemorrhage within a relatively short time before
infective sequelae have time to be established.
*cellulitis, pleural inflammation may supervene,
especially where some dirty weapon is used, or where
clothing has been carried into the wound.
*Infection may be of many types, but staphylococci,
Proteus, coliforms and Clostridium perfringens are
commonly found on culture

Pneumothorax
*Pneumothorax: is defined as the presence of
air or gas in the pleural cavity (ie, the
potential space between the visceral and
parietal pleura of the lung).

entry of air into pleural space by disruption of the alveoli
due to:
1) sudden increase of intrathoracic pressure as in blunt
chest injury.
2)sharp penetrating injury, such as fractured rib
or stab with a sharp instrument.
3) Puncture of the pleura in attempts to place a subclavian
or internal juglar venous catheter.
4) Natural disease can also cause PNX ,which can lead to
sudden death. (rupture emphysematous bulla , tear at
the site of fibrous pleural adhesion, tuberculos lesion

Simple PNTHX
=A leakage through the pleura allows air to enter the pleural cavity, but
where the communication rapidly closes.
=The lung partly collapses, but if death does not supervene
The air is soon absorbed
=If the communication remains open
bronchopleural fistula
(with air in the pleural cavity but it is not under pressure, like type 2)
=Radiology is the best means of demonstrating the air in the pleural
cavity.

Tension pneumothorax
=When the leak in the pleura has a valve-like
action.
=air is sucked into the pleural cavity at each
inspiration, but cannot escape on expiration.
=complete collapse of shift of the mediastinum
to the opposite side

Sucking wounds
=When an injury of the chest wall communicates
with the pleural cavity.
=direct passage of air from the exterior.
=This type is most often seen in military
surgery, and may be complicated by
haemorrhage and infection.

Injuries of the heart
The heart is vulnerable to both :
1) Penetrating injuries
2) Blunt injuries

Penetrating injuries
*most stab wounds enter via the :
intercostal spaces through a rib costal
cartilage.
*Sometimes the sternum is penetrated by a
forceful blow that reaches the underlying
heart.
Rarely, an upward stab from the abdomen
reaches under the costal margin to penetrate
the diaphragm.

**The right ventricle is often injured by a stab
wound.
**A shallow stab wound may enter the
myocardium and not reach the lumen of the
:
ventricle
-Little disability.
-Coronary artery injury myocardial insufficiency or cardiac tamponade death .
**More often – especially in the right ventricle
the knife passes into the cavity.

Note 
** It is impossible to calculate how long the victim was able to carry on with his activities, often
a matter of dispute at a criminal trial.
**Many stab wounds of the heart are transfixing or ‘through-and-through’ injuries, the knife
entering one wall and emerging through another.
Left ventricle
Right ventricle
Thick wall
Thin wall
bleeding can be slight.
copious bleeding
the contraction may partly or wholly seal
the wound.
inability of the thin wall
to close the defect by muscle overlap and
contraction.
common for
persistent bleeding to occur.(tamponade)
absence of the muscular ‘self-sealing’
effect.
more dangerous

Blunt injuries
**All degrees of damage can occur, from mere
epicardial bruising to lacerations that open the
ventricular lumen widely
**are seen in civilian practice mainly in :
1) traffic accidents
2) falls from a height
3)stamping assaults
**any heavy impact (including a punch) can cause
fatal damage.

The cardiac injuries are usually on the front
of the organ, especially to the right ventricle,
though posterior bruising and laceration can
occur if the heart is compressed against the
thoracic spine, as in stamping assaults and
steering wheel impacts.

Ruptured interventricular septum as a result
of impact on the front of the chest. The
septum can tear without damage to the outer
walls of the heart.

Haemopericardium and
cardiac tamponade
**Bleeding into the pericardial sac may occur
from:
1)The surface/ the cavities of the heart.
2)intrapericardial segments of the roots of the great
vessels (aorta and pulmonary artery).
**Causes :
1)Mostly due to natural dz (ruptured MI ruptured
dissecting aneurysm of the aorta).
2)Chest injury.

**Cardiac tamponade is a serious medical
condition in which blood or fluids fill the
space between the sac that encases the
heart and the heart muscle.
**Normally the pericardium ( double-walled
Sac) contains a small amount (15–50 ml) of
fluid.
**Essential in the tamponade is the rate of
fluid accumulation in relation to pericardial
stretch and other
compensatory mechanisms.
Rapid : 200 ml of fluid
Slow: up to 1500 ml

penetrating cardiac
injury
Bleeding rate>drainage
Or exit hole in the pericardium
becomes blocked by blood
clot
no escape route from the
sac
Prevent the passive filling of
the atria during diastole
Dec. CO and BP
Inc. venous pressure
If unrelieved death may occur
contusion or laceration of the
heart

Injuries to great vessels
The most vulnerable vessel is the aorta.
Causes :
1)deceleration trauma (road and air accidents).
2)falls from a height.
Note 
Stabs of the upper part of the chest may pass
directly into the arch of the aorta,
especially on the right side of the sternum

Complete transection of the aorta in the distal
part of the arch. The victim was a car driver who suffered a
severe deceleration impact

Mechanism : in case of decelerated
trauma
thorax suddenly decelerated
the heart – being relatively mobile in
the chest
severe traction on the root of the heart
complete or partial rupture of the aorta
in the descending part of its arch

Mechanism : in case of falls from a
height
Theories :
1) The lesion is the result of the abdominal and
thoracic viscera being forced caudalwards by
the abrupt deceleration when landing on the
feet or buttocks. (Fiddler)
2) sudden rise in intra-aortic pressure.
(Tannenbaum and Ferguson)

=rupture occurs almost constantly at a point 1.5 cm distal to the
attachment of the ligamentum arteriosum.
=The pulmonary artery is much less vulnerable to
blunt trauma than the aorta but, in stamping assaults and
steering wheel impacts, it may be damaged by depressed rib
cage and sternal fractures.

COMPLICATIONS OF
INJURY
MOATH ABU BSHARA

INTRODUCTION
• Serious injury may cause instantaneous death
or delayed death from complications of the
original injury
• E.g. hemorrhagic shock vs. untreated wound
infection
• a direct chain of events can be traced from the
injury to the death,

BLEEDING
• Bleeding may occur :
• externally through lacerations and incised
wounds
• a natural passages, such as the bronchi
and trachea, oronasal passages….
• Internal bleeding :leakages of blood into
tissue spaces from rupture of vessels and
free bleeding into body cavities

BLEEDING
• Depends on:
• Total volume – tiny venules vs. ruptured
aorta
• Site – brain stem vs. pleural cavity
• Speed of loss– leakage vs. torrential

BLEEDING
• Delayed bleeding such as in blunt trauma leading
to subcapsular hematomas (liver, spleen, lung)
and aneurysms.
• Response to injury:
• 1) Musculoarterial spasm of local
vessels
• 2) Wall retraction
• 3) Type of injury (eg. crushing)

BLEEDING
• It is sometimes difficult to know how much of a
hemorrhage found at autopsy may be accounted for by
postmortem bleeding except in serous cavities
• Source of bleeding is usually obvious
• In large cavities like pleura and peritoneum, may take the
shape of a large clot
• Clot will have postmortem blood but usually is not
significant to alter the interpretation
• Copious bleeding can be seen in head injuries esp. the
scalp when placed in a dependent position

INFECTION
• Used to be much more common prior to antibiotic
introduction; previous homicide deaths were inflated
• Many inherently non lethal wounds became fatally
infected so that an assault became a homicide
• The types of post-traumatic infection are legion and vary
greatly from country to country
• G+ve, G-ve, anaerobes
• Clostridium tetani and Bacillus anthracis in some countries
• Death due to medical negligence is not an exoneration of
the perpetrator

PULMONARY EMBOLISM
• This is a most important topic in forensic pathology,
as the medico-legal implications of a fatal pulmonary
embolus are common and profound
• Pulmonary embolism is the most underdiagnosed
cause of death where no autopsy is performed
• As with infection, an originally non-lethal injury may end
in death because of venous thrombosis and pulmonary
embolism, making what might be a simple accident or a
common assault into a grave legal issue

PULMONARY EMBOLISM
• Trauma increases likelihood because:
1. Injury increases coagulability; peak 1-2 weeks
1. Injured leg and pelvis regions can cause local thrombosis
around muscles/fractures
1. Injury may confine victim to bed or because dependency is
necessary, increasing stasis due to pressure on
musculovenous pump and reduced venous return

PULMONARY EMBOLISM
Postmortem Antemortem
surface Shiny , glistening Dull, matted
Consistency Soft jelly like Firm
Color Dark red Greyish red (varies
from place to place)
Components Blood Blood, plasma
Shape Forms cast of vessel Cast of original vessel,
stumps do not match

PULMONARY EMBOLISM
• Post-mortem clot may be adherent to the ante-mortem
embolus and sometimes forms a sheath around it so that
the true nature is obscured unless a careful examination
is made
• On cutting the lung with a knife, ante-mortem emboli may
be seen in the more peripheral vessels -like toothpaste
coming from a tube.
• The importance of the differentiation between antemortem
emboli and post-mortem clot is emphasized, as the legal
issues hanging upon the unequivocal diagnosis may be
very important

PULMONARY EMBOLISM
• It is difficult to use histological criteria to date the free
embolus from the lungs, as it is the thromboendothelial
junction that provides the most information.
• The best method, therefore, is to examine the residual
thrombus, almost always in the leg veins, to see if the
oldest part could have formed as far back in time as the
suspected traumatic event

PULMONARY EMBOLISM
• Vein containing thrombus must be excised and stained, looking
for:
1. Fibrin stained with PTAH – purple stained
2. Endothelial proliferation – most useful in 1st week
3. Collagen fibers – peak appearance at 2-3 weeks
4. Hemosiderin – blue granules via Perl’s reaction; peak on 2nd to
3rs weeks
5. Capillary buds – canalize at 3 months and full lumen forms
within 6-12 months

FAT EMBOLISM
• Seen after injury to bone/fatty tissue
• Fat globules penetrate through capillaries and reach
pulmonary circulation, onward to vital organs
• Manifestations dependent on amount of fat liberated
• Pulmonary: Cause vascular obstruction leading to edema
and ventilation problems
• Cerebral: Infarcts and causes neurological abnormalities
depending on side obstructed, usually leading to coma or
death .

FAT EMBOLISM
• There is usually a delay between trauma and cerebral fat
embolism while fat builds up in the lungs, so that a ‘lucid
interval’ occurs, which may be confused clinically with the
development of an extradural or subdural hemorrhage.
• Fat embolism is also associated with:
1. Burns , Barotraumas
2. Soft tissue injury
3. Diabetes
4. Osteomyelitis
5. Surgical procedures (esp. mastectomy)

FAT EMBOLISM
• After trauma fat appears in lung in different amounts
• For pulmonary fat embolism, Oil Red-O stained sections
are classified according to amount of fat seen:
• Grade 0: none seen
• Grade I: found after some searching
• Grade II: easily seen
• Grade III: present in large numbers
• Grade IV: present in potentially fatal
numbers
In systemic fat embolism, no such grading is possible; they are
either absent or scanty, or they are abundant

FAT EMBOLISM
• Clinically pulmonary fat embolism presents similarly to
cerebral fat embolism due to formation of pulmonary
edema in both instances
• Systemic fat embolism occurs when enough fat is
embolized through the pulmonary circulation
• Fat may lodge in the brain kidneys or myocardium

FAT EMBOLISM
• Appear as petechial hemorrhages over the body; most
around chest, face and eyelids.
• Internally in white matter of the brain, brainstem, and
cerebellum
• In the myocardium, fat may be seen in the interfibres
capillaries and in the kidney glomeruli may be stuffed with
stained fat. There can be fat in the retina and in the optic
nerve, which, in survivors, can cause visual impairment
• Histologically appear as central fat globule on ORO stain

BONE MARROW EMBOLISM
• Mainly seen in traumatic deaths with long bone fractures
• Also seen in
1. Convulsive deaths (e.g. tetanus, eclampsia,
electroconvulsive therapy)
2. Electrocution
3. Procedures involving bone marrow (e.g. thoracotomy,
sternal puncture)

FOREIGN BODY EMBOLISM
• Granulomata seen in lungs of IV drug abusers
• Caused by cutting agents such as talc and flour, or
injecting unevenly crushed tablets
• Can also be through shotgun pellets which also causes
extensive soft tissue injury increasing chance of fat
embolism

ACUTE RESPIRATORY DISTRESS
SYNDROME
• Following severe lung injury, such as gross impact upon
the thorax or blast injury from explosion, or from
aspiration of gastric contents, infections, toxins, systemic
shock, irritant gases, near-drowning and many other
causes, the lung epithelium may suffer ‘diffuse alveolar
damage’
• Patient develops edema that leads to dyspnea and
hypoxemia
• Pathologically the lungs show a stiff oedema that
progresses to a rigid, infiltrated lung if survival is long
enough

ACUTE RESPIRATORY DISTRESS
SYNDROME
• On autopsy the lung is hard and retains its shape and edema,
doubling its weight; ‘dry edema’ appearance
• Type I pneumocytes are shed, alveoli hemorrhage(destructive
phase), then type II pneumocytes fill the alveoli and an
inflammatory reaction fills interstitium ( proliferative phase)
• Alveolar proliferation occurs in survivors leading to fibrosis that
will eventually lead to death by lung fibrosis

ACUTE KIDNEY INJURY
• Rapid decrease in the kidneys’ excretion function or urine
output or both
• Common after extensive muscle damage and severe burns
and specific poisons causing acute tubular necrosis
• Similar changes seen postmortem, though much less
severe

AIR EMBOLISM
• Medico-legally significant: due to trauma (surgical or
therapeutic), barotrauma, criminal intervention
• Interruption of circulation by bubbles of gas entered
through venous circulation
• Air is compressible and therefore heart contractions fail to
move
• Always right sided, death is immediate or up to 2 hours
• Debate as to amount needed, ranging from 15ml to 480ml
• Commonly seen in barotrauma, Criminal abortion
• Rare in artery, due to rapid absorption by tissues plus has
a long route to reach cerebral circulation

AIR EMBOLISM
• Best examined using CT
• On dissection the vessel may be submerged underwater;
bubbles escaping indicating air presence
• If air is substantial, blood may appear frothy
• Cannot be diagnosed if severe delays occur between death
and autopsy due to air dissolving
• Decomposition will not allow diagnosis of air embolism
due to production of gases in putrefaction

SUB-ENDOCARDIAL HEMORRHAGE
• Flame-shaped hemorrhage seen in left ventricle,
intraventricular septum, papillary muscles
• Seen after
1. Sudden profound hypotension – shock
2. Intracranial damage – head injury, cerebral edema, craniotomy
3. Obstetric catastrophes – ruptured ectopic pregnancy, abortions
4. Poisoning – heavy metal toxicity esp. Arsenic

SUPRARENAL HEMORRHAGE
• Originally thought to be exclusive to Waterhouse
Friderichsen syndrome
• Part of a general response to stress
• Death is delayed, occurring 2-21 days later, bleeding is
found to be fresh on autopsy
• Adrenals swollen to a large walnut size
• Can be due to:
• Trauma, especially RTA
• Fetal anoxia
• Infective septicemia
• Tumor invasion(e.g. prostate)

Deaths associated with
pregnancy
Firas saleem

⚫Maternal deaths
⚫Deaths associated with abortion
⚫The autopsy in abortion deaths
⚫Amniotic fluid embolism

⚫ Death of a woman while pregnant or within 42
days of termination of pregnancy, irrespective of the
duration and site of pregnancy, from any cause
related to or aggravated by pregnancy or its
management but not accidental or incidental
causes.
Definitions

⚫maternal mortality ratio
⚫(MMR) = number of maternal
deaths during a given time period per 100,000 live
births during the same time period
⚫maternal mortality rate
number of maternal deaths during a given time period
per 100,000 women of reproductive age during the
same time period.
Statistical measures for maternal
mortality

⚫DIRECT : directly related to pregnancy &/or delivery,
only happens through pregnancy
⚫ INDIRECT: Diseases not directly related to
pregnancy or delivery but are exacerbated by it.
Diseased or events unrelated to pregnancy and not
influenced by pregnancy
⚫ COINCIDENTAL : Diseased or events unrelated to
pregnancy and not influenced by pregnancy.
⚫Late : death between 6 weeks – 1 year of delivery
CLASSIFICATION OF MATERNAL
DEATH

direct
•
Preec
lamps
ia
•
Amni
otic
fluid
embo
lism
•
Genit
al
tract
trau
ma
•
indirect
•
Aorti
c
dissec
tion
•
Cong
enital
heart
diseas
e
•
Veno
us
thro
mboe
mboli
s
•
COINCIDE
AL
collisi
on
•
Illicit
drug
toxici
ty
•
Most
cance
rs
•
Some
suicid
es

⚫ It is unpredictable, unpreventable and untreatable
with high mortality rate (80 %) . Clinical triad of :
Hypotension
cardiac arrest
Pulmonary vasospasm
Coagulopathy with severe bleeding
During or just after labor or caesarean section due to entry
of amniotic fluid, fetal hair, amniotic & fetal squamous
cells into maternal circulation
AMNIOTIC FLUID EMBOLISM
SYNDROME

Embolus in the small vessels
of the lungs
Triggers acute anaphylactic
response
Cardiopulmonary shutdown,
clotting cascade, consumptive
coagulopathy (DIC)

⚫the lungs
• Renal glomeruli: fibrin thrombi is usually found in
capillary lumens (indicating DIC as a part of AFES)
• Uterus: mucosal bleeding sites
Amniotic fluid material in mural vein
autopsy pathology

⚫Pre-eclampsia: raised blood pressure, oedema,
proteinuria.
⚫ Predisposing factors essential hypertension, renal
disease, obesity( asssociated with HELLP syndrome
(hemolysis, elevated liver enzymes, low platelet
count)
• Eclampsia: clonic tonic seizures occurring in a patient
with pre- eclampsia. It has high mortality rate.
HYPERTENSIVE DISEASES OF
PREGNANCY

⚫ The most common cause of direct maternal
deaths .
⚫CAUSES: • uterine atony , placenta previa,
retained placenta , placental abruption
,creta syndrome( increta, percreta, accreta)
, genital tract trauma, uterine rupture
and abortion
PERI & POSTPARTUM
HEMORRHAGE

⚫VENOUS THROMBOEMBOLISM
⚫ It occurs following C-section in the form of massive
pulmonary embolism.
⚫Pregnant women are 10 times more prone for VTE
⚫Autopsy pathology: examination of the entire length
of the pulmonary artery tree to show massive
thromboembolism
INDIRECT CAUSES

⚫inherent predisposition
⚫progesterone associated with weakening of the tunica
media (Elastic degeneration Mucin deposits
Attenuated muscle)
⚫Weakening of the wall of aorta, medium and large
arteries
⚫Aneurysm Dissection Rupture
CARDIO VASCULAR DISEASE
PATHOGENESIS

⚫CARDIAC DISEASES
⚫ congenital heart lesion with pulmonary hypertension
⚫ inheritable cardiomyopathy
⚫ acquired cardiac muscle disease
⚫SADS (sudden unexpected arrhythmic cardiac death
syndrome)
⚫valvular disease (IV drug users, rheumatic mitral valve
stenosis )
⚫PERIPARTUM CARDIOMYOPATHY: Heart failure
during the last month of pregnancy and up to 5
months post-delivery with all other causes excluded.

⚫low platelets ( laboratory data)
⚫ normal clotting factors and fibrin
⚫microangiopathic anemia
⚫ renal failure
⚫blockage of arterioles and veinules in myocardium
resulting in hemorrhagic infarction and acute heart
failure
THROMBOTIC
THROMBOCYTOPAENIC PURPURA

⚫ Pregnancy is a relative immunodepressed state
⚫ So listeriosis, tuberculosis, viral infections are more
aggressive ( HIV)
⚫ Type A/ H1N1 influenza : Mainly affects third
trimester , results in influenza pneumonitis, acute
lung injury, secondary bacterial pneumonia.
PREGNANCY ASSOCIATED
INFECTIONS

⚫HIV :More prevalent in low-income countries with
high HIV prevalence
⚫10 fold increase in maternal mortality
⚫Death is mostly due to TB or other opportunistic
infections or sepsis.

Prepared by:Abeer Dajani
Electrical fatalities

Electrocution
 Definition:is the passage of electrical current through the body
causing skin lesions,organ damage and death.

Factors affecting the severity of
tissue damage
I. Current(type,amount,pathway)
II. Voltage
III. Resistance
IV. Duration

 Type of current :AC is more dangerous than
DC.four to six times more likely to cause death.
 Tetanic spasm of muscles of hand preventing the
victim from releasing his or her grasp and this is
calledThe Hold on effect.
 Amount of current : the passage of 50–80mA
across the heart for more than a few seconds is likely
to cause death.

 Route of current: The current enters at one point and
then leaves the body at an exit point, usually to the earth.
 It tends to take the shortest route between entry and best
exit.Most common route current passes is from hand to
foot or hand to hand.
 Passage of current through heart or brain increases
mortality.
 Voltage :most fatalities occur with voltage between 110V-
380V(average 240)
 Electrocution is rare when voltage is less than 80V unless
humidity reduces resistance or contact is prolonged.

 Resistance :body tissues have variable resistance
between 500-1000 ohms
-bones,fat and tendons have high resistance.
-Nerves ,blood,mucus membranes and muscles have low
resistance.
-Skin has moderate resistance variable based on thickness
and dampness.
 Duration :death has been reported with as low as
24V when contact is maintaned for several hours.

Mode of death
 Death from electrocution can be caused by:
I. Current itself.
II. Secondary effect of burn.
III. Blunt force injuries due to fall caused by current.

Immediate mechanism of death
caused by direct passage of current
I. Ventricular fibrillation
II. Respiratory arrest:caused by intercostal muscles
and diaphram spasm and paralysis .
III. Paralysis of respiratory centers: ocurrs when the
current passes through the brain stem.

Autopsy findings
 Electrical injuries can be separated into three main
groups:
I. Direct tissue damage caused by current.
II. Thermal damage from conversion of electrical to
thermal energy.
III. Traumatic injury from muscular contractions
causing bone fractures or injuries from fall.

Skin lesions
Characteristic skin lesions :-
-Joule burns a Low voltage injuries at entry and exit
point.

Stages of development of skin lesions :
 classical lesion: small,circumscribed, crater like
indurated lesion with a chared grey or black center
surrounded by a zone of pallor caused by arteriolar
spasm and coagulative necrosis .this may be surrounded
by a zone of hyperemia with presence of vesicles.

 In high voltage burns,sparking may occur over many
centimeters.this can cause multiple spark lesions
giving rise to crocodile skin effect

Metallization:
 copper electrodes cause a bright green color metal
residue can be tested by chemical testing or by
scanning electron microscope .

Lightning :
 Typical fern like pattern known as litchenberg
figure.

Internal appearance
 In fatal electrocution ,gross findings in internal
organs may be absent .
 The usual mode of death is :-
1. cardiac arrhythmias: epicardial petechia may occur
and the body is either pale or slightly congested.
2. Respiratory arrest :pleural and intracerebral
petechia , congestion and cyanosis of the face.
3. Early or partial development of rigor mortis since
it may be acceleration developmet of rigor mortis
following tetanic contractions induced by electric
current .

FATAL PRESSURE ON THE
NECK
Noor Yaseen

■ Introduction
■ Mechanism of death in pressure on the neck
■ Manual strangulation
■ Strangulation by ligature
■ Arm-locks and ‘mugging’
■ Hanging
■ The sexual asphyxias: autoerotic
or masochistic practices

PRESSURE ON THE NECK MAY ARISE FROM
 Manual strangulation
 Ligature strangulation
 Hanging
 Direct blows
 Arm-locks
 Accidental lesions:- such as entanglement with
cords or falling onto the neck

MECHANISM OF DEATH IN PRESSURE ON
THE NECK
 Airway occlusion
 Occlusion of the neck veins
 Compression of the carotid arteries
 Nerve effects

STRANGULATION BY LIGATURE
Pressure on the neck may be effected by
constricting all or part of the circumference of the
neck by a ligature. This is sometimes called
‘garroting’, though strictly this refers to the
tightening of a noose around the neck by twisting
a rod within the ligature, a form of judicial
execution once employed in Spain. This method
had a refinement in which the back of the neck
was forced against a sharp spike which
penetrated the spinal cord.

In forensic practice, if hanging is excepted as a
separate entity, most ligature strangulations are
homicidal. Some are suicidal and a few
accidental, usually in children.

THE NATURE OF THE LIGATURE
 Cords
 Wires
 Ropes
 Belts
 Scarves
 Towels
 Stockings
 Strips of bed-linen
The ligature may be applied as one turn around the neck –
or even less, as homicides have been perpetrated by the
assailant pulling a U-shaped ligature against the front
and sides of the neck, while standing at the back.

 In the majority of cases, however, the ligature is
crossed over itself after passing a full circle around the
neck – and several turns may be wound around,
secured with one or more knots. These multiple turns
are common in suicide. they are more common in
suicide, where the determined victim is eager to
succeed.

THE LIGATURE MARK
 The appearance at autopsy naturally depends on
the nature and texture of the ligature.
 In homicide, where the ligature has been
removed by the killer, such a pattern may be of
great value in tracing its origin.

When a fabric has been used, such as a scarf or towel, the marks on the
neck are more difficult to interpret.

A fabric ligature may leave a sharply defined mark ,
which may be misinterpreted as being caused by a
narrow cord or wire.

The skin mark may remain red, especially if the ligature
was of softer material such as cloth, but cords, ropes
and wires tend to abrade the surface, which later
becomes yellow or brown and parchment-like. This is
seen particularly in hanging, when the friction and
chafing may be greater.
The stiff, brownish-yellow appearance occurs
postmortem and tends to become more pronounced as
the interval lengthens after death. The mark may be
slightly wider, narrower or the same width as the
actual ligature, depending partly upon how deeply it
cut into the skin. There is often a narrow zone of
reddened hyperemia at either margin of the mark.
This used to be taken to indicate that the ligature
must have been applied during life .

THE POSITION OF THE LIGATURE MARK
In strangulation, unlike hanging, the mark tends
to encircle the neck horizontally and at a lower
level. Typically it crosses immediately above or
below the prominence of the larynx and passes
back to the nape of the neck. In homicide, where
a single turn is used, there is often a cross-over
point where the two ends of the ligature mark
overlap. This may be at the front, side or back of
the neck, depending on the relative positions of
assailant and victim. When a knot is tied, it may
leave a mark on the skin and, of course, if
multiple loops are present, some or all of these
will be represented on the skin.

OTHER SIGNS OF LOCAL INJURY
IN LIGATURE STRANGULATION
 Scratches on the neck :- usually caused by the
attempts of the victim to pull away the ligature.
 Fingernail marks, sometimes linear and vertical, deep
damage in the muscles of the neck , laryngeal injury :-
may be present as in manual strangulation.
 Internally there may be superficial hemorrhage under
the ligature mark, though this is often minimal.
 The hyoid bone and thyroid horns may be fractured,
especially where the ligature rides at the level of the
thyrohyoid ligament.
 It is rare for the main thyroid plate or the cricoid to
be fractured unless gross violence was applied with
excessive pressure by a strong ligature.

WHERE MUCH BRUISING AND ABRASION IS SEEN, ESPECIALLY IF
SCATTERED AND AWAY FROM THE ACTUAL LIGATURE MARK,
THEN THE POSSIBILITY OF A COMBINATION OF MANUAL AND
LIGATURE
STRANGULATION MUST BE CONSIDERED

THE MODE OF DEATH
IN LIGATURE STRANGULATION
The mode of death is more often the ‘classic asphyxia’
picture than in manual strangulation, where sudden cardiac
death is common before congestive–petechial changes have
time to occur. The contrast in the appearance of the skin
immediately above and below the ligature mark is often
striking, with pale skin below, and a puffy, oedematous,
congested, cyanotic and haemorrhagic surface above.
Petechiae may abound in the eyelids, conjunctivae and facial
skin, and there may be bleeding from the ear and nose. This is
by no means invariable, and many ligature strangulations die
rapidly from vagal reflex cardiac arrest before any congestive
signs have had time to appear.
Accidental ligature strangulation – which may be actual hanging
if the body weight is thrown wholly or partially upon the
ligature – is seen in the tragedies that occur to young children,
who may become entangled in blind or curtain cords, usually
when their cot or playpen is left too near a
window.Occasionally accidental ligature strangulation has
been caused in adults when scarfs or other pieces of clothing
have become entangled in various types of machinery or
houshold devices.

ARM-LOCKS AND ‘MUGGING’
Throttling by pressure from an arm held around the
throat. The attack is usually made from behind, the
neck being trapped in the crook of the elbow. Pressure
is then exerted either on the front of the larynx, or at
one or both sides by the forearm and upper arm , it is
rapidly losing favor because of the number of
inadvertent fatalities due either to ‘asphyxia’ or to
reflex cardiac arrest.
The autopsy features are those of ligature strangulation
with a broad object. Some diffuse abrasion may be
seen, especially along the margin of the jaw or lower
face.
Internally there may be diffuse bruising.
The larynx may also escape damage, though if it is
pressed backwards against the spinal column the
thyroid horns and even the hyoid may fracture .

HANGING
Hanging is a form of ligature strangulation in
which the force applied to the neck is derived
from the gravitational drag of the weight of the
body or part of the body.

JUDICIAL HANGING
The aim was that, when the rapidly
falling body was suddenly arrested,
the cervical spine would be dislocated
resulting in traction on the spinal
cord with consequent spinal cord or
brainstem disruption. cervical spine
dislocation – occurring at various
levels – was common, with resulting
cord or brainstem damage. Though
cerebral function presumably ceased
immediately on cord or brainstem
damage,

SUICIDAL AND ACCIDENTAL HANGING
Hanging is almost always suicidal or accidental,
the former being by far the most common.
Hanging has many features in common with
ligature strangulation. Death is, however, more
often caused by reflex cardiac arrest from
pressure on the carotid structures. Many more
victims of hanging are found to have pale faces,
rather than the congested, haemorrhagic
appearance of the slower asphyxial type of death.

METHODS OF HANGING
 Typical method of self-suspension is to attach a thin rope to a high
point such as a ceiling beam or staircase. The lower end is formed into
either a fixed loop or a slipknot, which is placed around the neck
while the intending suicide stands on a chair or other support. On
jumping off or kicking away the support, the victim is then suspended
with all or most of his weight upon the rope .
 The many variations of this involve either the ligature or the height
of suspension. Wires, string, cords, belts, braces (suspenders), scarves,
neckties, stockings and numerous other devices may be used,
depending on availability.
 Successful hanging can occur from low suspension points, where the
person is merely slumped with part of his weight into the ligature.
Hanging can take place from doorknobs, bedposts and any other
convenient low securing point.
 It is unusual for a suicidal hanging to be sufficiently violent for
damage to the cervical spine to occur as the length of drop is usually
too short. Only occasionally will a person jump from a roof or other
high place with a rope around his neck – here severe injury can occur,
even decapitation if the rope is strong enough .
 More often the jump will be from an attic trapdoor or a tree, sufficient
to damage the vertebrae or atlanto-occipital joint.

THE HANGING MARK
 The circumstances will usually indicate the fact of hanging,
but sometimes the rope will break or become detached, and
the deceased will be found lying with a ligature around his
neck.
 The hanging mark almost never completely encircles the
neck unless a slipknot was used, which may cause the noose
to tighten and squeeze the skin through the full
circumference of the neck.
 In most instances the point of suspension is indicated by a
gap in the skin mark, where the vertical pull of the rope
leaves the tilted head to ascend to the knot and thence to
the suspension point.
 This gap is usually seen at one or other side of the neck or
at the centre of the back of the neck.

THE POSITION OF THE HANGING MARK
 The hanging mark is situated higher on the neck
than in strangulation, usually being directly
under the chin anteriorly, passing round beneath
the jawbones and rising up at the sides or back of
the neck to the usual gap under the knot .
 An exception may be seen where the suspension
point is low and part of the body is supported.

AUTOPSY APPEARANCES IN HANGING
 First, post-mortem hypostasis will occur in the legs and hands if the body
has been in the vertical position for at least a few hours. When the body is
cut down and laid horizontal for a considerable time, some or all of this
appearance may flow back into the usual pattern.
 Petechial haemorrhages are the exception rather than the rule, most
series reporting them in approximately 25 per cent of cases. Such
petechiae appear to occur more frequently in incomplete suspension but
are frequently present in the absence of significant congestion.
 Congestion itself is far less usual than a pale face.
 In the neck tissues there may be surprisingly little to find with an
absence of laryngeal fracture or strap muscle haemorrhage being a
common finding, especially if a soft ligature has been used.
 Fractures of both the hyoid and thyroid may be seen.
 Damage to the intima of the carotid arteries, often in the region of the
sinuses, may sometimes be found on careful dissection.
 In hangings with an unusually long drop, severe disruption of the larynx
can be found.
 Another Simon described a finding, which can frequently be observed in
cases of hanging, particularly in lower thoracic and lumbar spine, and if
the body is completely suspended: streaky haemorrhages on the anterior
aspects of the intervertebral disks (‘Simon’s haemorrhages’; ‘Simon’s
sign’; ‘Simon’s symptom’).

MECHANISM OF HANGING
 Stretching of the carotid sinus causing reflex cardiac arrest
 Occlusion of the carotid (and possibly vertebral) arteries
 Venous occlusion
 Airway obstruction resulting from pushing the base of the
tongue against the roof of the pharynx or from crushing of
the larynx or trachea
 Spinal cord–brainstem disruption
 While hanging shares some features with manual
strangulation, the majority of victims of hanging are seen
with pale faces rather than the congested, haemorrhagic
appearance associated with the slower death resulting from
pressure on the neck. This probably reflects a different
mechanism, with reflex cardiac arrest and carotid occlusion
more prevalent in hanging than in strangulation. Such
mechanisms cause death rapidly, with unconsciousness
resulting from bilateral carotid occlusion 3–11 seconds
after the application of circumferential pressure.

ACCIDENTAL AND HOMICIDAL HANGING
 Accidental hangings occur from two main causes.
 The first is entanglement in ropes or cords; this is
relatively uncommon, and is usually seen in infants and
children.
 On rare occasions, similar tragedies have befallen adults in
factories, farms or ships, where a trip or fall has
precipitated the victim head-first into machinery or
structures, where ropes or cords have caused hanging or
strangulation
 Homicidal hanging is very rare, outside abuse of human
rights and ‘lynching’. For one individual to hang another,
there must be either a disparity in their size and strength –
or the victim must be drugged, drunk or otherwise
incapacitated by fear, illness or senility. For a conscious,
presumably unwilling, victim to be hanged by another,
there will inevitably be signs of resistance, such as grip
bruises on the arms due to restraint, or signs of binding the
arms, wrists or legs.

THE SEXUAL ASPHYXIAS: AUTOEROTIC OR
MASOCHISTIC PRACTICES
 Auto-erotic asphyxia is a method of increasing sexual
excitement by restricting the oxygen supply to the
brain, usually by tightening a noose around the neck.
 Sexual masochism disorder (SMD) is the condition of
experiencing recurring and intense sexual arousal in
response to enduring moderate or extreme pain,
suffering, or humiliation.
 The sexual asphyxias occur much more frequently in
males than in females but there are several reports of
the latter indulging in this dangerous ,indicating that
males tend to use more apparatus, while females are
usually found naked with only a ligature in
evidence.The age of the male victims can vary widely,
but is most often seen in young to middle-aged adults.

FEATURES OF THE SEXUAL ASPHYXIAS
 The basic mechanism of the sexual asphyxias is
the production of cerebral hypoxia, which in some males
appears to produce hallucinations of an erotic nature.
 This hypoxia is most often achieved by constriction of the
neck by a ligature, which can be voluntarily tightened to
produce vascular obstruction and perhaps airway stenosis.
 Some autoerotic procedures use other means of hypoxia,
such as anesthetic agents and a variety of volatile
substances, tapering into ‘solvent abuse’.
 Whatever the mechanism, when cerebral hypoxia occurs
with its attendant erotic sensations, progressive loss of
voluntary control as consciousness fades allows the
constrictive device to slacken, so that the subject recovers.
As some fatal cases show clear evidence of repeated
previous escapades, it is obvious that the mechanism
usually functions quite successfully and that death was the
result of some unforeseen complication.

 A common practice is to place a fixed noose around the
neck, so that compression will cease as soon as
muscular tension on the free end is relaxed. This free
end may be passed down the front or back to be
fastened to the ankles, so that by extending the legs,
the noose around the neck is tightened.
 Similar hypoxia may be produced by placing the head
in a plastic bag, by pushing the head into a confined
space.

 The bonds may be sexually orientated, with straps around
the crutch or constricting the genital organs.
 The mouth may be sealed by adhesive plaster and the eyes
blindfolded.
 Transvestism is common, female attire being worn either
overtly or under male clothing. False breasts and nipples
may be fabricated with cloth, some males (often elderly) as
hidden transvestites, wearing female underclothing
beneath their suits.
 Fetishism is often seen, especially rubber or shiny plastic or
leather. Female wigs and make-up are sometimes
encountered.
 Pornographic literature is often within view and may be
spread around the body at the scene of death. The act is
sometimes performed before a mirror and masturbation is
common. The mere emission of semen found at autopsy does
not confirm sexual activity in itself, however, as post-
mortem discharge of semen from the meatus is common in
any type of death, not only in asphyxia.

 Occasionally, lewd writings are left near the body and even
upon the body surface.
 Perhaps more importantly, overt suicide notes are never
present, helping to distinguish the cases from definite self-
destruction. Another important piece of evidence against
suicide is the fact that, in some neck ligatures, the rope
may be padded by fabric to avoid leaving a telltale mark on
the neck – an act incompatible with an intention of suicide.
 Rarely, autoerotic gratification may be achieved by the
application of electric current, usually low voltage applied
to the genitals.

MEDICO-LEGAL ASPECTS OF THE
SEXUAL ASPHYXIAS
 Though all these features make the true nature of the death clear to the
medical examiner, it can sometimes be difficult to convince the police, the
coroner or judge – and especially the relatives – that death was accidental.
The stigma still attached to suicide and the revulsion felt at the perverted
sexual element may cause the relatives to prefer homicide as the cause.
 The judicial authorities often lean towards suicide, especially when they are
unaware of the existence of this strange syndrome of the masochistic or
sexual asphyxias. The doctor is often the only person able to explain the
relatively common occurrence of this phenomenon and assist in reaching the
correct conclusion.
 In these instances the circumstances are such that a mixed motivation must
have existed. For example, hanging by the neck in free suspension from a
tree or from the trapdoor of an attic is a situation from which escape is
impossible, even though sexual attributes such as nudity, bondage and
masking were present
 Recognition of the true nature of most of these deaths is vital for the medical
examiner, as spurious homicide investigations may be initiated if they are
misinterpreted. More commonly a false suicide verdict may result, which can
have financial implications in respect of life insurance. A mistaken belief in
suicide may be preferred by some families, however, rather than the shame of
a publicized sexual aberration

DIRECT BLOWS
 It is another cause for sudden cardiac arrest is a blow
to the neck or throat. This is the basis of the so-called
‘commando punch’. The edge of the hand is
brought forcibly across the side of the neck or the
front of the larynx. Direct violence to the carotid
region naturally causes gross stimulation of the
afferent nerve endings. Blows directly to the larynx
indirectly stimulate the sinus region or the laryngeal
sensory nerve endings may themselves trigger the
cardio-inhibitory reflex.
 It is well known that the hypopharynx and larynx
are particularly sensitive to stimulation.
 The testicles and uterine cervix also have a similar
reputation for leading to sudden cardiac death, if
unexpectedly overstimulated, especially when the
myocardium is pre-sensitized by
catecholamines released by fear or emotion.

Pathophysiology
of death
By Raghad Beitouni & Maryam Haj
Yehia

TYPES OF DEATH
– Somatic :
It is basically losing the connection with the environment on a sensory
level.
Unable to respond to stimuli like pain, communication or initiate
voluntary movement. But reflexes, cardiac and respiratory functions may
persist spontaneously or artificially.
– Cellular :
Simply, it means the death of cells on the metabolic level. Reasons like,
ischemia and anoxia contribute to such condition, as a result to
cardiorespiratory failure.

This is called cerebral death and the victims will be in “vegetative state”.
Higher levels of cerebral activity are selectively lost , pretty much is
somatic death.
If the brain stem is maintained, spontaneous breathing will continue
therefore cardiac functions are not compromised.
On cases where brainstem is dead , there is loss of vital centers that
control respiration and of the ascending reticular activating system that
sustains consciousness , therefore artificial help is needed or else cardiac
arrest will follow within minutes. Then Cellular death is expected.
BRAIN DEATH

Indication of death
1- Un-consciousness and loss of all reflexes with no reaction to painful
stimuli .
2- Muscular flaccidity immediately after cerebral and cerebellar functions
failure ( though they are physically capable to contract many hours after
the event ) .
3- Cessation of heart beat and respiratory movement .
- heart beat >>> prolonged auscultation , echocardiogram.
- respiration >>> prolonged auscultation over the trachea and lung
fields

4- Eyes signs
-Loss of the corneal and light reflexes and the pupil is in the mid – dilated position >>
relaxed neutral position of the pupillary muscles .
-Iris remains responsive to chemical stimulations hours after death
-Loss of pupils circular shape and regular size
-Loss of globe tension due to decrease in the arterial pressure
- The eye ball progressively becomes softer

- The cornea loses its normal glistening reflectivity due to laxity and
failure of lacrimal moistening
-Eye led >> incomplete closure >> due to muscle flaccidity >> two triangles
appear on the exposed sclera ( yellow > brown > black ) “ TACHE
NOIRE “
- Retina >>> “trucking” of blood in the retinal vessels due to breaking up
of blood into segments due to loss of BP ( one of the earliest positive
signs of death

Mode VS Cause of death
The mode of death :
the abnormal physiological state that pertained at the time of death.
EX: congestive heart failure , coma , cardiac arrest … these give no
information to the underlying pathological and should not be used as the
definitive cause of death

Manner of death
– The circumstantial events such as “ homicide , suicide , accidental or
natural cause “ .

1) Hypostasis
Cause :
Ceasing of circulation : no arterial propulsion or venous return and so
no blood movement through the capillary bed. This leads to gravity
pulling down the stagnant blood to the lowest possible points.
The RBCs are most affected , and plasma also drifts downwards to a
lesser extent , causing post – mortem “dependent edema “ , which
contributes to skin blistering .
Color :
Bluish red discoloration .
Locations :
On the lateral and dependent surfaces , upper surfaces of the legs
especially thighs , the coalesces and slide down the lowest areas

– Distribution of hypostasis
It depends on the posture of the body after death .
1- It’s most common when the body on the back with the shoulders , buttocks and
calves pressed against the supporting surface. This compresses the vascular
channels in those areas and so hypostasis is prevented from forming there, so, skin
remains white.
2- If the body remains vertical after death, as in hanging, hypostasis most marked
in the feet , legs , and to lesser extent in the hands and distal part of the arm.
 Local pressure can exclude hypostasis and produce a distinct pattern in contrast
in contrast to the discolored areas . Ex: Clothes, socks, bed markings...

Color
– The usual color is bluish red , but there is wide variation that
depends on the state of oxygenation at the time of death .
– congested , hypoxic state gives off darker color due to reduced
hemoglobin in the skin vessels.
– natural deaths from coronary or other diseases have dark
hypostasis .
– Color of hypostasis varies from area to area on the same body .

When death has been due to hypothermia or exposure to cold in the
agonal period, such as from drowning, the colour may assist in
confirming the cause of death; again this is relatively non-specific
because bodies exposed to cold after death (especially in mortuary
refrigeration) may turn pink after an initial stage of normal bluish-red
tint
 Mechanism, it’s not fully understood , but it’s obviously a result of
oxyhemoglobin forming at the expense of the reduced hemoglobin .
 Sometimes the originally bluish hypostasis turns pink along the upper
part or the horizontal margin , and the lower parts remaining darker
this is due to the hemoglobin being more easily re-oxygenated where
RBCs are backed less densely.

Unique Colors
Cherry – pink of carboxyhemoglobin Very unique, the first
indication to carbon monoxide poisoning
– Cyanide poisoning >>> dark blue – pink.
– Deaths from septic abortion where Clostridium perfringens is the
infecting agent >> pale bronze mottling may sometimes be seen
on the skin . This is not confined to gravity
– Skin hemorrhage varying in size from small petechiea to large
blotches and even palpable blood blisters may develop in areas of
hypostasis. Common areas : back of shoulders and neck, front
chest even if he was lying on his back.

TIME
Hypostasis can appear within half an hour of death or it may be delayed
for many hours.
The phenomenon appears at a variable time after death – indeed, it
may not appear at all, especially in infants, old people or those with
anaemia.
Once hypostasis is established , there is controversy about its ability to undergo
subsequent gravitational shift, if the body is moved into a different posture , the
primary hypostasis may either :
• Remain fixed.
• Move completely to the newly dependent zones .
• Partly fixed and partly relocated

Hypostasis in Organs
– Just as blood settles in dependent skin, so it does in other tissues and
organs.
– The importance in forensic autopsy work is the differentiation of organ
hypostasis from ante-mortem lesions.
- Intestine : jejunum and ileum
- - The lungs >>> there is a marked difference in color from front to back
.
- myocardium >> dark patches in the posterior wall of the left ventricle
.
- retro - esophageal hemorrhage at the level of the larynx –artifact error.

Hypostasis vs Bruises
Hypostasis : regular , diffuse engorgement of the surface vessels , the
color varying between purple red and bright pink , density vary from
place to place , without sudden change in color nor any sharply
circumscribed areas as in bruising . Hypostasis on dependent areas.
Bruises can be any where with discoid and irregular margin, rarely
cover a large area with uniform density – and do not have a
horizontal margin.
If there is difficulty in differentiation between them (Racial
pigmentation, or really deep cyanotic hypostasis),,, the classic test is
to : incise the suspected area to see if to under laying blood is
intravascular ( hypostasis ) or infiltrating the tissues outside the
vessels (contusions ) .

Differentiating between the two:
Intravascular (blood is in the most superficial layer of the dermis )- hypostasis
Infiltrating the tissues outside the vessels (blood is in deeper skin layers or
underlying tissues and fixed. - Bruise
If a post-mortem pressure mark ( belt or tight clothing) crosses an area of
Hypostasis : there will be a pale bloodless zone
Bruise : it won’t be affected .
Histological examination is the main way to actually differentiate
between them.

Rigor Mortis
It’s stiffening of muscles after death . The usual method of testing is by
flexing and extending the joint .
Range of times where rigor appears can be summarized as follow :
-The flaccid period immediately after death ( 3- 6 hours ) >>
-rigors first appears in the smaller muscle groups( jaw , facial muscle …) >>
wrists and ankles >> knees , elbows and hips
-Rigor mortis >> spread to involve the whole muscle mass within a
variable period but in average ( 6 – 12 hours ) >> this remains constant
until the muscle mass begins to undergo autolysis .
-Full rigor >> ( 18- 36 hours )

Factors affecting Timing of Rigor
Mortis
The temperature in the surrounding environment ( the colder the
environment the slower the process )
The availability of glycogen and ATP in the muscle is crucial element in rigor
formation .
The following is reasonable ‘ spot check ‘ for temperature conditions :
– - if the body is warm and flaccid >>> less than 3 hours
– - if the body is warm and stiff >>> 3 – 8 hours
– -if the body is cold and stiff >>> 8 – 36 hours
– - if the body is cold and flaccid >>> more than 36 hours

Rigor Mortis in tissues
The iris is affected so that ante mortem constriction or dilatation is
modified. making the pupils unequal, confirming the fact that the post-
mortem position is an unreliable indicator of toxic or neurological
conditions during life
In the heart, rigor causes the ventricles to contract, which may be
mistaken by the inexperienced pathologist for left ventricular
hypertrophy

Rigor in the dartos muscle of the scrotum can compress the testes and
epididymis which, together with the contraction of muscular fibres in the
seminal vesicles and prostate, may lead to post-mortem extrusion of
semen from the urethral meatus. This has been wrongly attributed to
sexual activity before death.
In hair follicles, the myth of beard grows after death, it comes from the
fact that erector pili muscles attached to the hair follicles can cause a
pimpling or ‘goose-flesh’ appearance with elevation of the cutaneous
hairs.

Gross effects in rigor mortis
There has been controversy over whether rigor mortis only stiffens the
muscles or actually shortens them .
-” Sommer’s movement “
- Smith:decrease in glycogen which leads to shortening in muscle.but
its not recognizable as the flexor and extensor muscles groups oppose
each others
It can never be assumed that the posture of rigor in which the body is
found was that which obtained at the time of death .

Cadaveric spasm
– Cadaveric spasm is a rare form of virtually instantaneous rigor that
develops at the time of death with no period of post-mortem flaccidity
– It seems confined to those deaths that occur in the midst of intense
physical and/or emotional activity
– It presumably must be initiated by motor nerve action, but for some
reason there is a failure of the normal relaxation
– The phenomenon usually affects only one group of muscles, such as
the flexors of one arm, rather than the whole body
– Ex : solder in the battlefield , person fall into water ,gripping a gun as
evidence of “true suicide “ rather than a “planted weapon “ in a
homicide

Cold vs Heat stiffening
At extremes of temperature the muscles may undergo a false rigor .
- Cold once intrinsic body heat is lost , the muscles may harden because
body fluids may freeze .
- Heat >> causes stiffness , as the protein becomes denatured and
coagulated >>> this depends on the intensity of heat and the time for
which it was applied

Decomposition
Hypostasis and decomposition occur relatively soon after death
when somatic death has occurred , but cellular death is incomplete .
The process of decomposition begin in some cells while others are
still alive.
Death is a process rather than an event
Decomposition is a mixed process >> ranging from :
- autolysis due to internal chemicals - external process introduced
by bacteria and fungi from the environment .
Decomposition varies from environment to environment , from
body to body , and even from one part of the same corpse to
another.

Putrefaction
– The usual process of corruption of the dead body begins
at a variable time after death, but in an average
temperate climate may be expected to begin at about
3 days in the unrefrigerated corpse

Sequence of putrefactive changes
 First external naked – eye sign: Discoloration of the lower
abdominal wall , most often in the right iliac fossa where the
bacteria – laden cecum lies superficially. This discoloration spreads
over the abdomen, eventually the abdomen becomes distended
with gas.
 . The generalized spread of bacteria and discoloration of moist
tissues .
 “ Skin – slippage “ sacs (fragile sacs of clear, pink or red serous
fluid) due to upper epidermis loosening and breaking of this sacs
makes identification of fingerprints more difficult
 The scrotum and penis may swell up to remarkable size

 The face and neck become reddish and begin to swell , The pressure
may cause the eye globes and tongue to protrude
 Purging of urine and faeces may occur due to the intra-abdominal
pressure
 Bacteria from intestine and lungs travel to the venous system,
haemolysing the blood that stains the vessel wall and adjacent tissues
:“ marbling “
 Bloody fluid , which is liquefaction stained by hemolysis , may leak
from mouth , nostrils , rectum , and vagina . ( by this stage , some 2-3
weeks may have elapsed since death )
 After several weeks , the reddish – green color of the skin may deepen
to a dark green or almost black .

 Heavy maggot infestation will have supervened except in winter
conditions , and the destruction of skin by these maggot holes and
sinuses gives access to other bacteria from the environment .
 Internally , decomposition proceeds more slowly than at the surface .
( the lining of the intestine , the pancrease and the adrenal medulla
auto-lyse within hours of death , yet prostate and uterus may still be
recognized a year later . Brain quickly become discolored , and liquefy
within a month. Heart it’s moderately resistant
“ military plaques (consisted of calcium and soapy material)“ white
granularity on the epicardium and endocardium surfaces

 later putrefactive changes lead to breakdown of the thoracic
and abdominal walls .
 After several months, softer tissues and the viscera
progressively disintegrate , leaving the more solid organs
such as the uterus , prostate , and heart .
 eventually , the body will be reduced to a skeleton , with
ligament , cartilage and periosteal tags .

Decomposition in immersed
bodies
The old rule :the bodies decay twice as fast in air as in water is grossly
inaccurate , but emphasized the slower rate of decomposition.
Water slows up decomposition mainly because of the lower
temperature , and protection from insect and small predators .
The gas formation is the reason for the inevitable flotation of an un
weighted body, the usual posture of a freely floating body is face down
, as the head is relatively dense , and doesn’t develop the early gas
formation as thorax and abdomen .
As stated before , temperature is the major determinant or the rate of
decomposition .

Decomposition in buried bodies
– The rate of decay of bodies buried in earth is much slower than of
those in either air or water .
– The process of putrefaction may be arrested to a remarkable
degree in a certain conditions , allowing exhumation(‫الجثث‬ ‫استخراج‬
(several years later to be of a value .
The speed and extent of decay in interred corpses depend on a
number of factors :
– Deep graves
– Timing of burial
– The nature of the soil
– The animals – rodents
– The coffin

Formation of adipocere
Adipocere : a waxy substance derived from the body fat .
The change of adipocere is partial and irregular and almost the
whole body may be affected .
It’s caused by hydrolysis an hydrogenation of adipose tissue
causing the formation of greasy and waxy material of recent origin
which after years it becomes brittle and chalky .
Color: vary from white to grey or greenish green .
Smell: earthy , cheesy ammoniacal .
The formation of adepocere , as an alternative to total putrefaction
, requires certain environmental conditions .

Any importance?
– The point at which adipocere becomes visible to the
naked eye varies greatly, but it has been observed as early
as 3 weeks, though 3 months is a more typical period.
– it allows the form of the body and sometimes even of the
facial features to be retained in recognizable form.
– Injuries, especially bullet holes, may be preserved in a
remarkable fashion

– It may also preserve the omental, mesenteric and perirenal
adipose deposits; in addition, organs containing fat through
pathological or degenerative processes may be preserved by
adipocere forming in their parenchyma.
– Certain areas tend to develop adipocere, such as the cheeks,
orbits, chest, abdominal wall and buttocks. Only rarely is the face
preserved well enough by adipocere to be genuinely recognizable,
as disintegration of the eye globes and shrinkage of the tissues
around the nose and mouth obscure the most characteristic
features.

Mummification
Dryness of body tissues in place of liquefying putrefaction.
- Can be partial and coexist with other forms of decomposition in different areas of same
body, however, it is more likely to involve a larger area of body.
- It takes place in a dry environment that is usually but not necessarily warm!
Appearance:
- Desiccation and brittleness of skin that is tightly stretched across bony prominences.
- Brownish discoloration of skin +/- white patches added secondary to mold formation.
- Skin and underlying tissues are hard to dissection
- Internal organs can have a variable condition (may be partly dried or partly putrefied),
depending on the time of death

Forensic slides all together.pdf

Forensic slides all together.pdf

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