forensic traumatology

1. Stab wounds
Dr M Balaji Singh
Professor of Forensic Medicine
ACS Medical college and Hospital, Chennai.
Courtesy DR . SONO MAL RATNANI , Farhan ali (slide share)

2. Sharp force injuries
• Incised wounds
• Chop wounds
• Stab wounds

3. Multiple stab injuries(5),over
abdomen

4. Multiple stab wounds on the back

5. Multiple stab wounds

6. Massive stab
wound , over left
side of the back of the
chest

7. Stab wound with tailing

8. Stab wound

9. stab wound
definition: wound caused by a sharp pointed weapon driven in the
body, the depth of the wound being the greatest
dimension.
Further describing as:
1.penetrating wound:
• when the weapon after passing through tissues
opens in to some part or cavity of the body
• wound of entry present, but not wound of exit.

10. • 2.perforating wound:
when the weapon passes through & through
the body or body part making two wounds
i.e. wound of entrance, and wound of exit.
.

11. causative weapons
1- pointed, sharp, flat objects__ knife,
dagger, sword, sickle
2- pointed, smooth and rounded objects ___
needles,
3- blunt ended, rough surfaced __ iron crow
bar ( iron rod ), pickaxe

12. Entry wound of stab
• Sharp pointed weapon causes- incised like
stab wounds
• Blunt ended weapon causes- lacerated
like stab wound

13. FEATURES of stab wound
• having all the features of incised wound,
• but depth is more than other dimensions.
how to ascertain depth of wound:
1-in case of penetrating wounds:
- in living
- in dead body

14. depth of wound........
• In living – on the operation table by the treating
surgeon only
• in case of dead:
during autopsy, depth is assessed by
gauging or by gentle introduction of a blunt
probe.
2. in cases of perforating wounds: the wound of
exit is the guiding principle.
.

15. characteristics of wound of entry &
wound of exit
• wound of entry is generally bigger than the
wound of exit.
- pieces of cloth/fibres directed towards
wound.
- margins are clean cut & inverted.
- abrasion/bruising of edges/margins due to
effect of hilt of sword or dagger may be seen.
• shape of wound may corresponds the
shape of weapon

16. WOUND OF EXIT
- smaller with everted margins.
cloth fibres are directed out wards.

18. WEAPON ----------- SHAPE OF entry WOUND
• 1.Single Sharp Edged- Weapon----- Wedge Shaped
• 2.Double Sharp Edged -Weapon- ---- Elliptical Shape
3.Rounded Pointed ------------------- Circular
•
4.Pointed -------------------------------- Square or Cruciate
5.Double Edged Blunt ------ Circular With Bruising
•
6.Instrument Twisted Before
With Drawl.--------------------------- Triangular Or Cruciate (shape
of a cross) .

19. Medico legal importance- stab wounds
• Weapon used
• Manner of death
• Most of the time homicide, but suicide may
possible
• Direction of infliction of force
• Relative position of victim and assailant
• Time of infliction of wound- by findings of healing
or bleeding
• Cause of death- by damage to vital organs or
hypovolemic shock

20. Cuts on the clothes in stab
wounds
Clothes damages mostly in case of
homicide, or accidents.
and cuts on clothes corresponds to
site of stab wounds
In case of suicide clothes are usually intact.

21. Suicidal stab by 18 years boy, knife is still in
the second stab wound over chest

22. Surgical treatment
• Algorithm for stab injury
• Illustrated in flow chart
in Next slide

24. Chop wounds

25. Chop wounds

26. Chop wounds are -deep gaping wounds
by heavy sharp weapons

27. Gapping & Cleavge lines
• Skin tension lines(Langer’s lines)

28. Gapping……………
• Gapping of the wound seen in sharp force injuries.
• Margins of the wound are separated, giving a spindle
shape to a sharp linear cut.
• It is a vital reaction due to elasticity of the ‘ “langres
lines” in the skin .
• The wound will gape if cleavage lines (Langer’s lines)
are cut transversely or obliquely.
• Gapping is minimal or nil if cut along with these lines.
• Gapping not seen in case of cuts on dead body.

29. Gapping…..

30. Chop wounds

31. Chop wounds

32. Chop wounds

33. The nature of the chop wound
depends upon
• the sharpness of its blade,
• direction and angle of the blow,
• portion of the instrument caused the injuries
• differences in curvatures of the tissues,
and skin folding.
• Underlying tissue(fat/ bone/muscle) of involved
area

34. Chop wounds by axe
• ill-maintained weapons
have some nicks and rusty
deposits on edges and blades.
- preventing the weapon to produce pure incision.
• When sharpened,
- such weapons produce devastating incised wounds.
- Even bone may be transected with clean cut margins
with comparatively little effort.

35. Chop by axe…….
• A triangular trench like depressed
fracture or cut will be seen over
skull bone due to attack by the axe.
• which corresponds the cross-
section of the axe blade- indicating
the size and measurement of the
blade of the weapon- hence called
signature fracture.

36. chop wound- M L I

37. Chop wounds
• Direction
• Usually the lower end (heel) of the
axe strikes the surface first, which
produces a deeper incised wound
than the upper (toe) end.
The deeper end indicates the position of the
assailant

38. Chop wounds- direction of force
• In the skull, the undermined edge of the
fracture indicate the direction in which the
force is exerted,
• or the slanted one is the side from which
the force was directed
• In case of long bones, the bone fragments
get loosened on the opposite side of the force.

39. Defense wounds may be seen in case
of assault

40. Defensive wounds may associate with
homicidal stab or chop wounds

41. Thanking you