Tissue histopathology is important for estimating the age of injuries in forensic medicine. The presentation discusses the histological changes that occur over time in different tissues like skin, muscle, bone and brain around inflicted wounds. These vital reactions like hemorrhage, inflammatory cell infiltration and formation of granulation tissue can help determine if an injury was ante-mortem or post-mortem. The timing of cellular and biochemical changes in injured tissues can provide a window into how long ago an injury occurred. Understanding the histological healing processes in various tissues enables more accurate estimation of the age of wounds in medico-legal cases.

1. Tissue Histopathology and its
Importance in Estimation of Age
of the injuries
Presenter : Dr. A. Haricharan – 2nd year PGT
Moderator: Prof . Th. Meera Devi - H.O.D.
Dept. Of Forensic Medicine & Toxicology
RIMS, Imphal.

2. OBJECTIVES :
1. To determine the age of injuries by histopathological
findings and to correlate histopathological changes in
relation to time of injury.
2. To explain the importance of tissue histopathology, in
Clinical Forensic Medicine

3.  Damage to any part of the body due to application of
mechanical force Injury or Wound.
 The term wound describes the morphological and functional
disruption of the continuity of a tissue structure.

4.  Sec 44 IPC defines injury as “Any harm whatever illegally caused to
any person in body, mind, reputation or property.”
 Mechanical injuries may be due to blunt force, sharp force or by fire
arms.
 Ante mortem (or) Post mortem has to be ascertained
the age of the wound has significance
in forensic pathology and clinical forensic medicine.
 To establish the causal relationship between times of infliction
to the time of death, the age of the wound has to be determined
more accurately and objectively for it to be medico legally
important.

7. Bleeding from injury:
Oozing of blood
Serosanguineous
Healing

9. Histological findings:
time of injury
• Polymorphs cell 4 hours
• Basophilic mast cell loss granule 4 hours
• Leucocytes infiltration marked 4- 12 hours
• Scanty lymphocytes & monocytes after 12 hours
• Leucocytes form a marginal palisade 12 hrs- 24 hours
• Fibroblast ( mitosis) 15 hours

10. • Leucocytes peak 48 hours
• Granulation tissue forms 72 hours
• Collagen begins 3- 6 days
• Haemosiderin 3rd day
• Collagen & elastin after 2 weeks
• wounding stops at 6 weeks

12. Determining the age of a wound is challenging in forensic
pathology
(1) whether an injury was caused while the individual was
alive or during the agonal or postmortem period, and
(2) how long the victim survived after the wound was
inflicted
 After infliction of a wound, a series of vital reactions (e.g.
haemorrhage, inflammatory cell infiltration, formation of
granulation tissue) must be taken into consideration to
obtain convincing proof of antemortem injury.
 These antemortem reactions are collectively termed
“vitality”.

13.  Because of the frequency at which they are encountered in
forensic practice the skin, skeletal muscle, and brain tissue
around inflicted wounds were the most commonly used.
 Histological analysis cannot determine whether a wound was
sustained before or after death .
 After wounding, however, the mRNA levels of cytokines and
enzymes typically change sooner than the protein levels and the
histomorphology .
 Hence, assays based on mRNA are suitable for estimating the
age of early-stage wounds.
PCR is a highly sensitive method.

14. Histochemical changes in injured
tissue:

15. Histochemical changes in injured tissue:
• Esterase & adenosine within an hour
triphosphatase
• Aminopeptidase 2 hrs
• Acid phosphatase 4 hrs
• Alkaline phosphatase 5-8 hrs
Tissue cathepsins increase almost immediately if the
stroma is damaged, & can be demonstrated with in 5
to10 minutes.
Serotonin appears in maximum concentration in about
10 minutes &
 Histamine in 20 to 30 minutes after wounding.

16. 1) Edges: The edges are swollen, everted, retracted,
and wound gapes.
Edges do not gape,
but are closely
approximated.
2) Haemorrhage: Abundant and usually arterial. Slight or more and
venous.
3) Spurting: Signs of spurting of arterial blood on the
body, clothing or in its vicinity present.
No spurting of
blood.
4) Extravasation: Staining of the edges of the wound and
extravasation in neighbouring
subcutaneous and interstitial tissues which
cannot be removed by washing.
Edges and cellular
tissues are not
deeply stained. The
stain can be
removed by
washing
5) Coagulation Firmly coagulated blood in wounds and
tissues present
. No clotting or soft,
friable clot.
6) Vital reaction: Signs of vital reaction present, i.e.,
inflarmnation and repair.
No signs of vital
reaction
7) Enzyme
histochemistry:
ncreased activity of esterases, adenosine
triphosphate, aminopeptidase, acid and
alkaline phosphatase.
Diminished or no
enzyme activity.

17. BRIEF
ESTIMATION OF AGE OF INJURIES FOR
DIFFERENT TISSUE INJURIES AND
BONES AND BURNS

18. Bone callus in fracture bone
time
• Hemorrhage Immediate
• Bone necrosis 2 days
• Organization of clot 4 days
• Granulation tissue 5 days
• Proliferation & infiltration of 7 days
osteogenic cells

19. Bone callus in fracture bone: (continuation)
• Fibroblastic reticulam 10 days
• Soft callus 2 wks
• Hard callus 6-8 wks
• Healing of fractured bone 12-16 wks

22. Healing of abrasion
time
• Oozing Immediate
• Reddish scab/soft covering 6 hrs -1day
• Brownish scab 2-3 days
• Black brownish 4-5 days

23. Healing of abrasion
• Black scab shrinks at margins, 6-7 days
start separating
• Hypopigmented area 7-14 days
• Healed, unrecognizable 2 wks
abrasion area

24. Healing of Abrasions

25. Bruise colour changes:
time
• Red fresh up to 6 hrs
• Recent 24 hrs
• Bluish, light blackish tinge 2-3 days
• Brownish/dark bluish (hemosiderin) 3-4 days
• Greenish bruise (biliverdin) 4-6 days
• Yellowish (bilirubin) 7 days
• Faint yellowish 7-14 days
• Normal 2 weeks

27. Lacerated wound:
Duration Gross findings
• Fresh Bleeding or fresh clot is attached;
margins are red, swollen & tender.
• 12-24hrs Margins swollen, red & covered by
dried blood clots & lymph.
• 3-5 days Margins strongly adherent with each
other & covered by dried crust.
• 6-7 days Crust/scab falls off or can easily be taken
off with soft reddish tender scar.
• Few wks Scar is whitish, firm & painless.

28. Incised injury:
It becomes difficult to estimate exactly the time
since injury based on the size and contamination .
However, a rough estimate can be done based on
signs of healing.
time features
Fresh Haematoma formation
12 hrs Edges-red, swollen
24 hrs Scab of dried clot covering the entire area

29. Burn injury
• Redness immediate
• Blister formation 15 mins-3hrs
• Swelling, oozing, bleeding 24hrs
• Pus formation and visible pus, 36-48hrs
slough formation
• Thick pus formation-creamy layer 2-3 days

30. Burn injury
• Slough formation & granulation tissue 3-6 days
• Fall of superficial slough 7-8 days
• Fall of deep slough 3 wks
• Healing of deep burns 1 month
• Scar >1 month
• Contracture of joints Months

31. Subdural haemorrhage:
• Intact RBCs, fibroblastic activity 36hrs
at the margins.
• Loss of RBC contour, neomembrane 4-5 days
adjacent to dura is 2-5 layers of thickness.

32. Subdural haemorrhage:
• Lacked RBCs,clot liquefies, 6-10 days
12-14 layers of fibroblasts,
hemosiderin laden phagocytes seen,
neomembrane visible grossly.
• Fibroblasts, capillaries & fibrin 11-14 days
subdivide the clot, fibroblasts migrate
around the edges of clot, siderophages
present on arachnoid side.

33. Subdural haemorrhage:
• Capillary formation, 15-20 days
original RBCs lysed membrane
1/3 to 1/2 dural thickness on the
side of dura , but variably thin on
arachnoid side.
• Liquefied clot, membrane same 3-4wks
thickness as dura on dural side and
½ dural thickness on arachnoid side .
Siderophages in membranes.

34. Subdural haemorrhage:
• Hyalinization of membranes, 1-3 months
more of collagen & of some
thickness as dura on arachnoid side.
• Hyalinized neomembrane 3-6months
resembling dura.

35. MLI:
The major roles of histology in forensic practice
are as follows:
1. Diagnosis of disease from microscopy of tissue
2. Age of wound estimation
3. Identification of person
4. Confirmation of gross examination finding
5. Discovering new entities of diseases or findings
something which is not visible on gross
6. Piece of evidence in a forensic case
7. Effect of trauma
8. Entry and exit wound of firearm, lightning and
electrocution
9. It is of great importance in sudden death,asphyxia,
10. trauma and age determination cases

36. THANK
YOU !