undergraduate Forensic Class on Wet specimens

1. Demonstration class
WET SPECIMEN Examination
Dr. Salam Bitam singh
Senior Resident

2. Identification
This is a wet specimen of skin showing a Tattoo
mark in the design of a spider and the swastika
sign.

3. Tattoo
Defined as designs made in the skin by multiple
small picture wounds with needles or an electric
vibrator dipped in colouring matter.
Dyes commonly used are
Indian ink, carbon black
Cinnabar or vermilion(mercuric sulphide)
Chromic acid
Indigo,cobalt,prussian blue(ferric ferrocyanide)
Ultramarine(blue).

4. Sl.
No
.
Colouring Materials Colour
produced
1 Chinese black, carbon dust Black
2 Indian Ink, Chinese ink Blue black
3 Prussian blue Blue
4 Ultramarine,vermilion,cinnabar Red
5 Ochre Brown
6 Chromic oxide Green

5. Types of Tattoo
1. Permanent or
temporary
2. Involuntary
/Accidental :
those resulting
from gunshot
wound of the
entrance.

6. Pigment Deposition
 Optimum depth for pigment deposition: Superficial
layer of dermis
 Below the epidermis : Very slowly becomes fainter
 Deeper layer of dermis : Removed by phagocytises
Tattoo faded usually in 8-10 years.

7. Examination of Tattoo
Causing vesication by applying a little heat
Peeling off the epidermis by rubbing or treating
the area with 3% H2O2
In cases of the Faded Tattoos
 UV lamp or rubbing the part and examining
under the magnifying lens
Infra Red Photography
Lymph node near a Tattoo shows deposition of
the pigments.

8. Complications of Tattooing
Septic inflammation
Erysipelas
Abscess
Gangrene
Syphilis
AIDS
Leprosy
T.B

9. Erasure of the Tattoo marks
 Surgical Methods
 Complete excision and skin grafting
 Burns
 Scarification
 Carbon dioxide snow
 Electrolysis(5-8milliamphere of current passed)
 Laser beams: Dyes get vaporised
 Over tattooing with some pigments Like titanium oxide for
white colour.
 Confluent small pox and chronic eczema
 Caustic substances like mixture of papain in glycerine or
zinc chloride in tannic acid.(produce inflammatory reaction
and superficial scar)

10. M.L.I
1. Identification
2. Language
3. Race/Nationality
4. Religion
5. Occupation (sailors , transworld tourist )
6. Sex interest and moral deviation as well as mental makeup e.g
 Homosexuals: blue bird over the hand between base of thumb and
forefinger
 Definite perversion: indecent imprints over the body parts
7. Social strata( criminals,prostitues etc from nature of designs and the
pigment used.
8. Drug addicts (concealing of injection marks)
9. Gang members

11. 2. WET SPICEMEN

12. Identification :
It is a wet specimen of the human heart showing an entrance and an exit wound
of the firearm.

13. Heart Anatomy

14. Heart Anatomy

15. Entrance wound :
Over the left
ventricle(apex region)
which is circular and the
tissue around its margin
are inverted measuring
......cm X....cm.

16. Exit wound over the Right
Ventricle near the base of
the heart which is larger
and irregular in shape
measuring ...cm X ....cm,
the tissues around the
margins are everted.
Tract of the Wound :
Tract goes supero medially
toward the right involving
Left ventricle-LV cavity-
Interventricular septum-RV
cavity-RV wall

17. M.L.I
Type of the Weapon : Rifled Firearm
Direction of firing : Super medially toward the
right.
Cause of Death: injury to the vital organ.
Relative position of the victim and the
assailant can be known
Manner of injury : Homicidal

18. 3. Wet Specimen
Identification
It is a wet
specimen of
human heart
showing stab
wound injury
over the left
ventricle.

19. Characteristics
Shape of the injury
: Elliptical with
clean cut margins
Penetrating injury
as it passes through
the ventricle wall
and entered into
the cavity.

20. M.L.I
Type of the Weapon: Sharp pointed weapon
Direction of the force : From above downward
and left to right
Cause of death: Injury to the vital organs
Manner of production: Homicidal/suicidal.

21. 4. Wet Specimen
Q. Estimate the age of the given Foetus and
write its MLI.

22. Time line
1. Inta- Uterine age :
 0-7/10 days: ovum
 1st wk – 8th wks: embryo
 8th wks – delivery : foetus
2. Post delivery
Neonate: Delivery -28th day
Infant : 0-1yrs
Child : 1-12 yrs
Adolescent : 12-18 yrs
Adult : more than 18yrs
Minor : Less than 18 yrs
Major: more than 18 yrs

23. Bony Development
Age (IU) Appearance Centre of ossification
1.5 Month (IU) Clavicle
2 Months Each half of Mandible
3 Months Ischuim
4 Month Sacral segment ( Upper, Mid), Middle Ear Bone
5 Month Calcaneum
6 Month Sternum
7 Month Talus
8 Month Sacral Segment (Lower)
9 Month Femur (Lower End)
10 Month Cuboid, Upper end Tibia

24. Ossification centres of the foot
Primary ossification centres present at birth
Visible on x-ray from birth:
a. calcaneus: 6 months in utero
b. talus: 7 months in utero
c. cuboid: 9 months in utero
d. metatarsals: 9 weeks in utero
e. phalanges: 3-10 months (proximal to distal)
Primary ossification centres developing after birth
Become visible on x-ray from:
1. lateral cuneiform: 1st year
2. medial cuneiform: 3rd year
3. intermediate cuneiforms and navicular: 4th year
Secondary ossification centres
At the age of 3 years, secondary ossification centres of the navicular,
metatarsals and phalanges should all be present. The last secondary
ossification center to develop is the calcaneus appearing at 5 years.

25. Age of the Foetus
Gestational Age can be Determined from
 Maturation of the Chorionic Villi
 Length of the foetus from crown to the heel
 Ossification centres.

26. Specimen
↓
Approx. Length of Foetus
↓
Apply Haase Rule
↓
Approx. Age
↓
Comment upon the following:
How to proceed for age determination of
foetus in spotting?

27. Length of the foetus to calculate the approximate
age
Scalp Hair present or not and length
Eyes state of maturity
Eyelashes/Eyelids present or not.
Nails present or not/soft or thick/reached tip of
finger or not.
Sex can be recognized or not.
Signs of Viability absent/present
Can comment on internal organs and on level of
muconeum whether it is in Duodenum/ Large
intestine.
State of Skin whether wrinkled or smooth

28. Write down the Medico-Legal Significance
( Very important for all spots)
For e.g: 1. Still-born child
2. Criminal Abortion
3. Infanticide
4. Fabricated Abortion
5. Marriage
6. Divorce
7. Adoption.
8. Inheritance

29. Age and the Foetal length
1. When measured in cm
 Haase's formula (Carl Friedrich Haase a
German obstetrician).
Up to 5th Month of IUL
Age(months) = square root of the length(CHL)
 Rule of Morrison (1964):
From 5th Month of IUL
This rule states that the crown heel length of the
foetus in centimetres, divided by five gives the
age in Lunar month.

30. 2. When measured in inches.
Age (lunar Month)= length in inches/2+(-)1
Length divided by two plus or minus one

31. Crown-heel length (CHL) the distance from
the crown of the head to the heel in embryos,
foetuses, and infants

32. The comparison of
the foetal crown-
rump length shows
the enormous
increase in size
during the foetal
period.
The foetal crown-
rump length at 8
weeks amounts to
just 3 cm while that
of the foetus at birth
comes to over 30 cm
(highly schematic
drawing)
Crownrump length (CRL) the distance from the crown of the he
ad to the breech in embryos, fetuses, and infants; the equivalen
t of sitting height in older subjects.

33. Specific Features of a particular age :
At the end of First Month (Embryo)
• Length is about 1 cm
• Weight is about 2.5 gm
• The Eyes are seen as dark spots
• The Mouth seen as a cleft
At the end of Second Month
• Length is about 4 cm
• Weight is about 10 gm
• The hands and feet are webbed
• The Placenta begins to form
• The Anus is seen as a dark spot

34. At the end of Third Month
• Length is about 9 cms
• Weight is about 30 gm
• Eyes Closed and Pupillary Membrane appears
• Nails starts appearing
• Neck is formed
At the end of Fourth Month
• Length is about 16 cms
• Weight is about 120 gm
• Sex can be recognized
• Lanugo hair is seen over the body
• Convolution begins to develop in brain
• Meconeum is found in the duodenum
At the end of Fifth Month
• Length is about 25 cm
• Weight is about 400 gm
• Nails are distinct and soft
• light hair appears on head
• Skin is covered with Vernix Caseosa
• Meconeum is seen at the beginning of large intestine

35. • At the end of Sixth Month
• Length is about 30 cm
• Weight is about 700 gm
• Eyebrows and eyelashes appear
• Skin is red and wrinkled. Subcutaneous fats begins to be deposited.
• The testes are seen close to the Kidney
•
• At the end of Seventh Month
• Length is about 35 cm
• Weight is about 900-1200 gm
• Crown-rump length is about 23 cms
• Foot length is about 8 cms
• Nails are thick
• Eyelids open and pupillary membrane disappears
• Skin is dusky red, thick and fibrous
• Muconeum is found in the entire large intestine
• Testes are found at the external inguinal canal
• Gallbladder contains bile
• Caecum is seen in Right iliac fossa
• Ossification centre is present in the Talus
•

36. At the end of Eight Month
• Length is about 40 cm
• Weight is about 1 Kg to 2.5 Kg
• Nails reach to the tip of finger
• Scalp hair is thicker
• Left testis is present in the scrotum
• Placenta weight is around 500 gm
At the end of Ninth Month
• Length is about 45 cm
• Weight is about 2.5 Kg to 3 Kg
• Scalp hair is dark and 4cms long
• Meconeum is seen at the end of large intestine
• Ossification center are usually present in the lower end of
femur, in Cuboid and Capitate bone.

37. Foetus No.1
Q. Estimate the age of
the given Foetus and
write its MLI.

38. Foetus No.1
 Morphology : It is a wet specimen of the human foetus
having a length of 9 cm and weight about 30gm
 Findings:
 Eyes : closed, papillary membrane appears
 Nose and mouth cleft present.
 Neck formed
 Limbs developed and differentiated.
 Nails appears and membranous.
 Umbilical cords present and
 External genitalia developed but Sex can’t be differentiated.
Applying Hasse’s rule the age of the given foetus is of 3
Months IUL

39. M.L.I
MTP can be performed by a single Doctor.
The foetus in nonviable.
Ossification centres are seen at Ischuim

40. Foetus No.2
Q. Estimate the age of
the given Foetus and
write its MLI.

41. Foetus No.2
 Morphology : It is a wet specimen of
the human foetus having a length of 16
cm and weight about 120gm
 Findings:
 Eyes : developing but closed
 Lanugo hairs seen on the body
 Skin covered with vernix
 Fingers and toes differentiated.
 Nails present.
 Umbilical cords present and
 External genitalia developed and Sex
can be differentiated
 Meconium is found in the deudenum.
 Convulusion developed in the brain
Applying Hasse’s rule the age of the given
foetus is of 4 Months IUL old

42. M.L.I
MTP should be performed after opinion of
two Doctors is indicated.
The foetus in nonviable.
Ossification centres are seen at the Sacral
segment ( Upper, Mid), Middle Ear Bone

43. Foetus No.3
Q. Estimate the age of
the given Foetus and
write its MLI.

44. Foetus No.3
 Morphology : It is a wet specimen of
the human foetus having a length of
24 cm and weight about 400 gm
 Findings:
 Eyes : developing but closed
 Lanugo hairs seen on the body
 Skin covered with vernix caseosa
 Light hair appears on the head
 Nails present distinct and soft.
 Umbilical cords present and
 External genitalia developed and Sex
can be differentiated
 Meconium is found in the begining of
the large intestine.
Applying Hasse’s rule the age of the
given foetus is of 5 Months IUL old

45. M.L.I
MTP should be performed after opinion of
two Doctors is indicated.
The foetus in nonviable.
Ossification centers are seen at the Calcaneum

46. Foetus No.4
Q. Estimate the age of
the given Foetus and
write its MLI.

47. Foetus No.4
 Morphology : It is a wet specimen of the
human foetus having a length of 30 cm and
weight about 700 gm with the umbilical cord
attached to the placenta
 Findings:
 Eyebrow and eyelashes appears, eyelids are
adherent, membrane pupillaris present
 Lanugo hairs seen on the body
 Skin reddish and wrinkled with subcutaneous
fat begins to deposit covered with vernix
caseosa
 Light hair appears on the head
 Finger Nails present distinct and thickened.
 Testis are seen close to the kidney
 Meconium is found in the midpart of the
large intestine(transverse colon).
Applying Hasse’s rule the age of the given foetus
is of 6 Months IUL old

48. M.L.I
MTP cannot be performed as the feotus is
above 20 weeks old.
The foetus in nonviable.
Ossification centres are seen at the
Sternum(upper segment)

49. Foetus No.5
Q. Estimate the age of the given Foetus and write
its MLI.

50. Foetus No.5
Morphology : It is a wet specimen of the human foetus
having a length of 40 cm and weight about 1.5-2 kg
with the umbilical cord attached to the placenta
Findings:
 Skin reddish and not wrinkled with subcutaneous fat
deposited covered with vernix caseosa
 Scalp hair thicker 1.5 cm in length
 Finger Nails reach the tip of the fingers.
 Left Testis present in the scortum
 Placenta weight 500gm.
Applying Hasse’s rule the age of the given foetus is of 8
Months IUL old

51. M.L.I
MTP cannot be performed as the feotus is
above 20 weeks old.
The foetus is viable.
Ossification centres are seen at the Sacral
Segment (Lower) and lower sternum.