Forensic Medicine

1. REGIONAL
INJURIES

2. Head injuries
 Head injuries occur as a result of:
Traffic accidents
Assaults
Falls .
 If the brain is affected, the injury is
serious.
 If the brain is not affected, the injury
is simple.

3.  Closed head injury:
when the dura is remains intact.
 Open head injury:
when the dura is lacerated.

4. Head injuries
1. Injuries of Scalp
2. Injuries of Skull
3. Injuries of brain

5. Injuries of Scalp
1. Bruising of scalp
2. Laceration of scalp
3. Infections

6. Injuries of Scalp
• Scalp injuries may or may not be
associated with fracture of the
skull.
* Hair around the injury must be
shaved for proper examination.

7. Bruising of scalp
 A bruise over the scalp is covered
by hair, can only be detected by
palpation.
 Marked swelling is a common
 Bruising may occurs immediately
or may be delayed .

8. Laceration of scalp
 Laceration of scalp bleeds profusely
and dangerously even fatal blood loss
can occur.
 There is problem to differentiation
between incised wound and
laceration:

9. Differentiation between incised
wound and laceration:
 Blunt laceration has:
1. Irregular and Bruised margins
2. Head hair crossing the wound are
not cut.
3. Hair bulb and tissue bridging ( small
nerves and vessels ) are in the depth
of wound.

10. Black eyes
 Black eye is also called Periorbital
heamatoma, Spectacle
haemorrhage, RACCOON EYES,
 Causes
1. Direct violence
2. Gravitational seepage
3. Fracture of anterior cranial fossa

11. Fractures of skull

12. Fractures of skull
 The fractures of skull can occur
either by direct or indirect
violence.

13. Direct violence
1. Compression of the head by
obstetric forceps during delivery.
2. When head is crushed under the
wheels of a vehicle.
3. When head is struck by a moving
object, eg, brick, bullet,
machinary, hammer, axe etc.

14. HEAD INJURIES

15. Direct violence
4. Head in motion striking an object,
eg, in falls and traffic injuries.
5. Repeated blows to the head as in
boxing `PUNCH DRUNK syndrome`.

16. Indirect violence
1. Fall from a height on feet or
buttocks.
2. Pressure transmitted from the below,
eg, by an explosion.
3. A blow on the chin when the force is
transmitted from the mandible to the
skull.

17.  The base of skull is relatively
weak part due to its irregular
shape and foramina,
therefore it is the most
common site of skull
fractures.

18. MECHANISM OF SKULL
FRACTURE
 Direct injury to the skull:
 1. Fractures due to local deformation
( Struck hoop analogy).
when skull receives a focal impact, there is a
momentary distortion of the shape of
cranium. esp. infants.
The area under the impact bends inwards,
a compensatory distortion or bulging of
other areas occur.

19.  2. Fractures due to general
deformation:
Skull is compressed like elastic sphere.
when skull is deformed, compression occurs
on the concavity of curved bone and tension
force on convexity.

20.  Puppe`s rule:
 When two fracture lines meet at a
same point then the second fracture
line never cross the first fracture line.

21. Types of fractures of the
skull
1. Fissured fracture.
2. Depressed fracture.
3. Comminuted fracture.
4. Pond or indented fracture.
5. Gutter fracture.
6. Penetrating fracture.
7. Elevated fracture.
8. Spider web fracture or mosaic fracture.

22. Fissured ( linear), Hairline
fracture.
 This is a linear fracture or crack
involving the outer or inner table or
both.
 Such fracture cannot be detected by an
X-RAY.
 It can only be detected at autopsy.
 It is caused by direct or indirect
violence.

23. Fissured ( linear)
fracture.

24. Diastasis or sutural
fracture
 MOTORCYCLIST`S fracture:
In children and young adults a linear
fracture may pass into a suture line and
causes a diastasis or opening of the
weaker suture between bones.
 The most commonly involved suture is
sagittal.
 Common in child abuse syndrome.

25. Depressed fracture
 This is cause by a heavy weapon with
a small striking surface, eg, hammer.
 The fracture bone is driven inward and
its shape may be indicate the type of
the weapon, therefore it is also know
as SIGNATURE FRACTURE.

27. Comminuted fracture
 The bone is broken into two or more
pieces.

28. Comminuted fracture
 This is caused by
* Vehicular accidents,
* Falls from height
* Blow from weapon with
large striking surface.

29. Pond or indented fracture
 Pond fracture occur in children due to
elasticity of their skull bones.
 The fracture is due to forcible impact
against some protruding object.
 Fissured fractures may be seen round
the periphery of the dent.

30. Pond or indented fracture

31. Gutter fracture
 When a part of the thickness of skull
bone is removed, eg, in glancing bullet
wounds.
 It is usually accompanied by irregular
depressed fracture of the inner table.

32. Gutter fracture

33. Penetrating fracture
 This is clean cut opening due to a
penetrating weapon, eg, dagger, rod
or bullet.

34. Elevated fracture
 Elevation one end of bone
above the surface of skull
while the other end may dip
down in the cranial cavity.

35. Spider web fracture or
mosaic fracture.
 A comminuted depressed fracture
may also have fissure radiating from it
forming a spider web.

36. Fracture of base of skull
It is caused by
i. Direct violence (not common)
ii. Indirect violence (common)
e.g fall from height, blow on chin
iii. Blast from below

37. Fractures of base of skull
Sites of fractures:
1. Anterior cranial fossa
2. Middle cranial fossa
3. Posterior cranial fossa
4. Around the foramen magnum.

38. FRACTURE OF ANT. CRANIAL
FOSSA
CAUSES:
1) Direct Impact 2) Heavy Blow On Chin 3)
May result from contre coup injuries.
MENIFESTATIONS:
It manifests by escape of blood & CSF
from nose & blood in the orbit result in
black eye.

39. FRACTURE OF MIDDLE CRANIAL
FOSSA
CAUSES:
 Direct Blow behind ears
 Crash injuries of head
MANIFISTATION :
 Escape of blood and CSF from ears
 Mastoid haemorrhage from fracture of
middle cranial fossa (battle’s sign)

40. FRACTURE OF POSTERIOR
CRANIAL FOSSA
CAUSES:
 Direct impact on back of head
 Escape of blood and CSF in tissue of
back of neck

41. RING (FRACTURE AROUND
FORAMEN MAGNUM)
CAUSES :
1. It results from fall from height on feet &
buttocks.
2. Sudden violent turn of head on spine.
3. Severe blow on vertex
4. Heavy blow directed underneath the
occiput or chin.

42. Mechanism of cerebral
injuries ( Principles )
1. The adult skull is a remarkably strong
structure. Unless it is fractured, it does
not change shape.
2. Injury to the brain can occur without
injury to the skull.
3. Any impact (blow) on the head
produces momentary acceleration.
Brain responds by gliding and rotation
as the head is fixed .

43. Mechanism of cerebral
injuries ( Principles )
4. The harmful effect is increased when
the brain movement is prevented by
the bony prominences .
5. Since the cerebellum is smaller and
lighter, it is less likely to be damaged
by rotational strains

44. Coup and Contre
coup injuries

46. Coup injuries
A coup injury ( coup = blow ) is one
which occurs immediately subjacent to
the area of impact.

47. Coup injuries
 If the head is fixed and there is
violent impact over the occiput, the
fracture and underlying brain damage
will be located beneath the site of
impact.

49. Contre coup injury
 A contre coup injury ( contre =
opposite; coup = blow ) is one
which is situated on the contralateral
side of the area of impact.

51. Classification of injuries
to cranial contents
1. Acceleration/Deceleration injuries
2. Impact injuries

52. Acceleration/Deceleration
injuries
1. Diffuse neuronal injuries
2. Diffuse axonal injuries
3. Subdural haematoma

53. Diffuse neuronal injuries.
 It is due to acceleration/deceleration
movement of the head.
 Characterized by diffuse neuronal
damage involving brain stem.
 Damage consists of intracellular
disturbances and conduction defects
at synaptic junctions.

54. Diffuse axonal injuries
 It occurs due to rotational strains to
the head, damage the axons and
blood vessels.
 Stretching of the axons leads to
disruption and loss of function.

55. Impact injuries
1. Cerebral concussion
2. Cerebral contusions
3. Cerebral lacerations
4. Intracranial hemorrhages

56. Intracranial hemorrhages
1. Epidural hemorrhage
2. Subdural hemorrhage
3. Subarachnoid hemorrhage
4. Intracerebral hemorrhage.

57. Cerebral concussion
 Cerebral concussion characterized by
gross physiological disturbance of
brain function due to diffuse neuronal
injury but with little or no anatomical
changes.
 There is sudden loss of consciousness
and spontaneous recovery .

58. Retrograde amnesia
 The patient is unable to collect the
exact manner in which he was injured.

59. Post traumatic
automatism
 The brain injured person may speak or
act in an apparently purposeful
manner but has no recollection about
it afterwards.

60. Cerebral contusions
 Cerebral contusions are caused by
extravasations of blood from traumatically
ruptured blood vessels.
 Mostly found in frontal and temporal lobes.
 They are characterized by small punctate
or streak like haemorrhages.
 A golden brown area of gliosis known as
blood cyst, results when contusion is
absorbed.

61. Intracranial
haemorrhages
1. Epidural haemorrhage
2. Subdural haemorrhage
3. Subarachnoid haemorrhage
4. Intracerebral haemorrhage.

62. Epidural haemorrhage
 Epidural or extradural haemorhage, is
bleeding between the dura and skull.
 It is commonly seen in falls and RTA.
 It may be acute or subacute.

63. Acute epidural haemorrhage
 It is due to rupture of MIDDLE
MENINGEAL ARTERY.
 Classical picture is: initial loss of
consciousness then a lucid interval,
followed by coma due to raised
intracranial pressure.
 Death is due to respiratory failure due
to compression of brain stem.

64.  LUCID INTERVAL: it is a state of
consciousness between two states of
unconsciousness.

65. Sub acute epidural
haemorrage
 Occurs when fracture tears dural
sinuses, middle meningeal veins or
diploic veins.
 Symtoms appear after 3 or more days.
 Lucid interval – 50 % cases.

66. Medicolegal significance
1. Epidural hematoma on the
contralateral side should be carefully
excluded.
2. Patient may discharged from the
hospital during lucid interval and die
at home.
3. Condition may resemble
drunkenness, and patient may die in
police custody.

67. SUBDURAL HAEMORRHAGE
(HAEMATOMA)
It occurs between under surface of dura & outer
surface of arahcnoid .

68. CAUSES of Subdural haematoma:
1. Trauma
2. Rupture of aneurysm in cerebral
blood vessels
3. Rupture of bridging or
communicating veins
4. Common from trivial injuries not
sufficient to cause
unconsciousness or of fracture
skull.
5. Cerebral neoplasms
6. Bleeding disorders.
7. During anticoagulants therapy.

69. SUBARACHROID HAEMORRHGES:
It is haemorrhage between arachnoid & pia
mater.
CAUSES: TRAMAUTIC CAUSES:
1) Contusion or laceration of brain
2) Explosive blast
3) Asphyxia by strangulation
4) Traumatic asphyxia
5) Damage to vertebral arteries.

70. NATURAL CAUSES:
1. Rupture of aneurysm.
2. Atherosclerotic changes in old persons.
3. Leaking cerebral haemorrhage
4. Diseases like leukemia.

71. INTRACEREBRAL HAEMORRHAGE
Causes:
 RTA
 Fall from height
 In fatal head injury cases as a result of
cope & contre cope injuries.

72. SPONTANEOUS
HAEMORRHAGE
1. Obese person
2. High Blood pressure
3. Rupture of Aneurysm
4. Degenerative arterial disease

73. D/D OF TRAUMATIC & SPONTANEOUS
HAEMORRHAGE (APOPLEXY)
Apoplexy Trauma
1. Spontaneous bleeding in brain
2. Cause B.P, Atherosclerosis
Aneurysm
3. Ganglionic regions involved
4. Coma starts from beginning
5. Young healthy person
Not spontaneous
Head injury
White matter of frontal or
tempo- occipital region
4.coma from beginning or
concussion, Loss of
consciousness & long
coma
5. Adults & middle age.

74. Injuries to Spine and Spinal
Cord
1. Concussion
2. Compression
3. Pithing
4. Laceration

75. SPINAL CONCUSSION
It is transient loss of function of spinal cord,
following a severe injury to spinal cord.
Recovery is within hours few days e.g.
Causes: severe blow to back, fall from
height, RTA Railway accident.

76. RAILWAY SPINE OR TRAUMATIC
SPINAL NEURASTHENIA
It occurs in RTA, Railway accidents, mine
workers trauma,
Its ML importance as it leads to claim of
compensation

77. SYMPTOMS
1. Backache, insomnia.
2. Weakness of limbs, sexual asthenia,
incontinent bladder.
3. Tingling sensation & burning sensation.
Complete recovery may occur unless the
cord is lacerated

78. WHIPLASH INJURY
It is momentary dislocation of C4 – C6 cervical
spine. It is due to blow on chin, eyebrow, striking
head against windscreen in RTA, Mechanism:
Hyperextension of head.

79. DISLOCATION
The commonest sites being C4 – C6. If the
level of compression is above C4 region,
death is immediate due to paralysis centre
of Resp. muscle.

80. PITHING
It is the process of killing by pushing a needle
in nape of neck between C2 – C3. It damages
medulla & upper cervical cord contain
respiratory centre.
Infanticide by pithing is common.

81. CHEST: Flail Chest (Collapse of
the chest)
 It occurs when at least three
successive ribs are fracture at two
points creating a floating segment
of chest wall.

82. Chest: Flail Chest (Collapse of
the chest)
Floating segment is sucked inward during
inspiration.
Dysponea, Cyanosis, Pneumonia and Injury to
heart etc.

83. Paradoxical Respiration
 Breathing in which part of chest wall
moves in on inspiration and moves out
on expiration.

84. Abdominal injuries
In case of abdominal injury, the trivial injury
like abrasions may be found externally, but
gross and fatal injuries are frequently
present.
The abdominal wall may allow the mesentry,
gut, stomach and liver to be pin and crash
across the spine with severe internal
haemorrhage.

85.  So, whenever there is history of
injury to abdomen, the patient
should be kept under observation.
 The most important viscerae to be
injured are:
i. Spleen
ii. Liver

86. The spleen is most susceptible to
injury due
 Weakness of supporting tissues
 Thin capsule
 Extreme friability of its pulp
SPLEEN

87. It is ruptured,
i. By fall
ii. Blow on abdomen
iii. Crush injury due to RTA
iv. Spontaneous rupture may occur due
to
a. Malaria
b. Leukemia
c. Typhoid
d. Kala. azar

88. LIVER
The susceptibility of liver injury is
due to
i. Large size
ii. Central location
iii. Relative Friability
Cause of rupture is a fall, Blow, or
kick on abdomen, RTA etc.

89. The death occur due to shock and
haemorrhage. Sometimes bleeding
occurs between capsule and liver
(subcapsular Haematama) and serious
symptoms became apparent only when
the capsule ruptures.