abrasion forensic medicine undergraduate class.ppt

forensic class

1. 1

2. Injury
Hurt
Wound
Mechanism of injury
2

3. 3

4. Epidermis
Stratum corneum,
lucidum,
granulosum
Stratum spinosum,
basale.
Dermis
Stratum
papillarosum,
reticularosum.
4

5. Involves superficial layer of skin.
No bleeding.
Movement b/w skin & rough object
Compression / friction
Classification
Scratches.
Grazed
Pressure
Imprint/Patterned
Heaping up of Epidermis.
5

6. Linear
Point scratch

7. 7

8. 8

11. Brush burn/Gravel
rash/friction
burn/scuff or brush
abrasion
Dermal papillae

12. Road accidents
12

15. No scar formation.
Fresh : Red.
1 day : bright Red
scab.
2-3 D : Red Brown
scab.
4-5 D : Dark Brown.
6-7 D : Brownish
black.
8-10 D: Scab falls off.
Microscopic:
12 hrs: 3 layer zone
48hrs: scab
4-5 days: healed
5-8days: granulation
tissue
12 days: regression
15

16. 16

17. 17

18. 18
ANTE MORTEM ANTE MORTEM
ABRASIONABRASION
POST MORTEM POST MORTEM
ABRASIONABRASION
SURFACESURFACE MOISTMOIST DRIED AND DRIED AND
HARDHARD
BASEBASE REDDISHREDDISH YELLOWYELLOW
SCABSCAB PRESENTPRESENT ABSENTABSENT
VITAL VITAL
REACTIONREACTION
PRESENTPRESENT ABSENTABSENT

19. Erosion of skin produced by ants.
Irregular margin, pale.
No vital reaction.
Muco - cutaneous junction & moist folds of skin.
Excoriation by excreta.
Pressure sores.
Post mortem drying of skin
19

20. Site of impact
Direction of injury
Underlying organs
Patterned abrasions –
nature of force, type of
weapon/vehicle can be
known.
Age of injury
Crime scene
Crescentic abrasions
1.Throttling,
2.Smothering.
3.Sexual assault
4.Struggle
Fabricated abrasions.
Simple/ Griveous
20