firearm-injuries Dr. Shaban 123456(1).ppt

firearm-injuries D

1. Firearm Injuries

2. Terminology

4. Types of Firearm
1.Shotguns(ديصلا ةيقدنب)
2.Rifled Weapons

5. Shotgun ديصلا ةيقدنب
- The smooth-bore weapon consists of a metal barrel which has
parallel sides “double barreled”.
-They usually fire a large number of small
spherical lead shot.
-A shot gun is designed for use up to
30 – 50 m.
-Common sizes 19mm, 11mm.
-Ammunition هريخذلا)) consists of cartridge
(ةشوطرخ) (metal base containing a central firing
cap supporting plastic or cardboard tube). Inside the cartridge
there is a wad of paper & cardboard, with a mass of lead pellets.

6. Shotguns

8. SHOTGUN CARTRIDGE
Base it consists of a metal cylinder
(brass) which is continuous with a
cardboard or plastic cylinder
the case is rimmed which keeps the
cartridge correctly in the chamber
and facilitates extraction

9. FILLING OF CARTRIDGE FROM BASE
ARE-:
.1Percussion cap
.2Gun powder
.3Felt wad with cardboard
disc
.4The shot
.5Retaining cardboard disc

10. Wads
types
•glazed board
•straw board
•plastic


 Felt
shape
•disc shaped
•cup shaped
•bizzare shaped
Shot
consists of several
hundred small lead
shots .
number depends on :-
•the size of the load
•size of the individual
pellet

11. Rifled Weapons
-It differs from the shotgun:
1)They fire one projectile at a time.
2)There barrel has a spiral groove (bore).
3)Most of them have a mechanism for bringing a new round into the
breech

12. Rifled Weapons
Examples:
-- Automatic Pistol: self-loading weapon, where shells are put into
firing position by a gas operated delivery system.
-- Revolver: bullets are brought into position via a rotating cylinder
-- Rifle: a long barreled sporting or military weapon

13. -The ammunition comes in many sizes.
-It’s a closed metal cylinder carrying firing cap & a powder.
-When striking the cap the powder burns rapidly producing
huge volume of gas that propels the bullet with velocity
varying from hundreds to thousands of meters per second.
Rifled Weapons

14. RIFLE CARTRIDGE
-it has a metal cylinder
with a flat base which
projects as a rim - rimless
cartridge has an extractor
groove near the base
-primer cup is fitted in the
center of the base

15. Mechanism of Injury
-As missiles traverse the body it causes injury by
transferring some of it’s available energy
-Severity of damage is proportional to amount of
kinetic energy & the density of the involved tissue

16. Entrance Wounds
1.Shotguns:
-The mass of shot leaves the weapon initially as a
solid mass, which progressively diverges from
the weapon.
Contact Wounds (touching the skin)
-When a weapon is fired, the bullet, hot gases
from exploding gun powder & metal fragments
from the bullet & the gun barrel are propelled out
of the muzzle at the same time.
-The hot gases & metal fragments are blasted into
the body at the same time as bullet.

17. Contact Wounds cont.
- Round or oval central defect with an ‘abrasion collar’
(where the bullet has abraded the skin surface as it
passes through it). The size of the defect is comparable
to the size of the muzzle opening or bore of
the weapon.
- “Pink/red” staining of the skin (due to carbon
monoxide laden gases producing
carboxyhaemoglobin)
- Gun powder blackening of the wound edges &
surrounding skin (from soot & unburned propellant
gases).
-Circular bruise over the skin due to muzzle impact.

18. Contact Wounds cont.
Summery
-Wounds are circular
-There may be muzzle mark
-There may be a slight local burning to the skin & hair
-Redness from CO gases

19. Contact Wounds cont.
Muzzle
imprint
Burning
from the
powder

20. Near Discharge
- Within few cm of surface
-Large central defect with ‘stippling’ or ‘tattooing’
( small, dry, reddish abrasions caused by unburned
powder & small metal fragments striking the skin)
- Smoke soiling
- Lack of muzzle mark
tattooing
Intermediate Range

21. Intermediate Range
-Within 20 cm to 1 m.
- Diminishing of the smoke soiling but powder
tattooing persist
- Burning will be present
- The rim of the wound is irregular forming what is
called ‘rat-hole’.

22. Intermediate Range

23. Long Range (2-3m)
-Satellite pellet holes will be seen around the
central wound, which diminishes in size as the
range increases.
- the spread of shot in centimeters equal two to
three times the range in meters.
e.g. if the wound pattern is 20 cm across the
discharge was roughly 7 – 10 m so couldn’t be a
suicide.

24. Long Range ( 20 – 30 m)
-Abrasion collar
-No smoke soiling, burning or powder tattooing.
-Tissue displacement.
-Rarely fatal.

25. Differences between shotgun &
rifles in entrance wound
Rifled weapons:
- show increased amount of tissue destruction due to the
high velocities involved.
-Usually have an entrance and exit wound unless bullet
has struck a bony area such as the skull.
-Estimation of firing range is more difficult than with
shotgun weapons, but in general , contact wounds show
similar features of powder stippling, blackening,
burning, tissue disruption, & carboxyhaemoglobin
formation.

26. Exit wound
-Shotguns: Rarely produce exit wound because they
traverse the body, but if happened it may cause a
huge ragged aperture wound.
-Rifled weapons:
--Exit wound is usually everted with split flaps.
--No burning, smoke or powder soiling.
--if the bullet flattened or has destruct some bone
internally, exit wound may be more irregular and
sometimes very large in size.

27. Exit wound
Entrance Wound
Exit Wound
with split flaps

28. Exit wound

29. Accident, Suicide, or
Murder
-Suicides must show wounds which range within the
arms reach unless some devices is present to reach the
trigger.
-Suicides shoot themselves in sites of election which
include the mouth, the front of the neck, the forehead,
or the front of the chest.
-Discharge into the entrance wound are usually on the
side of the dominant hand, but this is not absolute.
-People almost never shot themselves in the eye or
abdomen & naturally not in inaccessible sites such as
the back.
-Women rarely commit suicide with guns & rarely
involved in firearm accidents.

30. Accident, Suicide, or
Murder
-‘A shot woman is a murdered woman until proved
otherwise’.
-Multiple firearm wounds suggest homicide, but this is
by no means inevitable.
-It’s unwise to state that a gunshot wound must have
been immediately fatal, unless destruction of brain
stem or heart or transection of the aorta has occurred.
-There are many instances of gross brain damage,
especially in the cerebrum, bring followed by
prolonged purposeful activity.
-In suicide weapon must be present, though it may be
at a distance from the body.

31. Doctors duty in firearm
injuries & deaths
-Any missile, foreign body such as wads and any
skin removed from the margin of a repaired
firearm wound should be carefully preserved for
the police.
-The skin in post-mortem examination around
the entrance wound should be removed & kept
without formalin, but refrigerated if necessary,
for forensic tests for powder residue.
-In many countries firearm injuries must be
reported to the police even if not fatal.

32. Thank You