Skull fractures can provide important forensic information about the cause and mechanism of injury. Simple or closed fractures involve only the bone while compound or open fractures communicate with the scalp or other tissues. The most common types are linear or fissured fractures, but depressed, elevated, comminuted, and perforating fractures can also occur. The location, direction, and features of fractures depend on factors like the area struck, force applied, age of the victim, and weapon used if any. Skull fractures carry risks of brain injury, hemorrhage, infection, and other complications. Forensic analysis of fracture patterns can help reconstruct the circumstances of injury.

1. Skull fractures- forensic aspects
Dr m balaji singh
Professor of forensic medicine
ACS medical college and hospital ,Chennai
Courtesy; suraj dhara, dr yassera hameed(slide share)

2. Medico legal importance -fractures
• Most of the skull fractures are due to falls / road
traffic accidents
• Homicidal fractures may possible due to
heavy weapons
• But fractures are very rare in self inflicted wounds

3. Fracture/wound Profile
• Wounds such as those produced from
- gun shots are often deep enough to produce
marks on the bones-
-perforating /gutter/signature fractures.
• other weapons like sword ,axe, hammer –
signature fracture -
• These marks can provide useful insights into the
manner and cause of death.

4. Medico legal importance -fractures
Any fracture in the bones will give some idea about the
• Weapon / instruments caused,
• mechanism of occurrence,
• direction and amount of force applied,
• Positions of victim and assailants,
• Reconstruction of scene of offence/
accident,
• Time since infliction of fracture,
• Cause of death.

5. Vault and base of skull

6. Skull fractures- vault and base

7. What is a fracture?
• A partial or complete
break in the skull
bone occurs as a result
of direct or indirect
impact.
• indicates that
substantial force has
been applied to the head
and is likely to have
damaged the cranial
contents.

8. Anatomy Of The Fracture
• The brain is surrounded by
1. (CSF)
2. enclosed in meningeal covering
3. and protected inside the SKULL and scalp.
•
The fascia and muscles of the scalp gives additional
cushioning
•
10 times more force is required to fracture a cadaveric skull with
overlaying scalp than the one
without

10. Relatively weaker areas of Skull (fractures
are more easily sustained at)
• skull vault
thin squamous temporal bone, and
parietal bones.
• Basal skull
•anterior cranial fossa
- the sphenoid sinus,
- cribriform plate of ethmoid
- the roof of orbits
- inner parts of the sphenoid wings
• middle cranial fossa
- the petrous temporal ridge
• posterior cranial fossa ,
- the areas between the mastoid and dural
sinuses
-and the foramen magnum.

11. Factors influencing fracture
1. Area of the skull struck
2. Thickness and bone density of the skull
3. Scalp & hair
4. Direction and force of impact
5. Age of the victim, elasticity of the skull bones, fusion of skull
sutures.
6. Weapon used- sharp / blunt, light / heavy, firearm
7. Position and support to the head at time of impact

12. Fractures - mechanism
• Direct injury –
• Compression : by obstetric forceps or under wheel of
a vehicle – by distortion of the shape of the skull
• Moving object striking the head : bullets, brick,
dagger
• Moving head striking an object : falls & traffic injury
• Indirect injury –
Fall on the feet or buttock – transmitting forces from
below upwards.

13. MECHANISM OF FRACTURE…..due to blunt force - deformation of
skull - local /general
• Due to local deformation – (Struck hoop
analogy)
• When skull receives a focal impact, there is a
momentary distortion of the shape of the cranium.
• The area under the impact bends inward (in
bending) causing a compensatory bulging of
other areas (out bending).

14. Due to general deformation
• Whenever skull is
deformed,
compression occurs on
the concavity of curved
bone ,
it
creates a tension force at
the bulging & produces
fracture.
- Arrows indicating
direction of compressing
force.

15. Fractures may be
• 1) Simple (closed)
if it does not communicate with the
atmosphere through any route
2) Compound (open)
if it communicated with the atmosphere
through any route
some continuity with injuries to the scalp or
nasal sinuses

16. Fracture TYPES
Fracture of cranial vault
• Fissure #
• Depressed #
• Elevated #
• Comminuted #
• Pond #
• Gutter #
• Diastatic #
• Perforating #
• Blow out #
• Expressed #
Fracture of skull base
• Ring #
• Hinge #
• Anterior cranial fossa #
• Middle cranial fossa #
• Posterior cranial fossa

17. Fissured #

18. Fissured or linear fracture
• MOST COMMON
type(70%)
• a break in the bone but
no displacement,
• The fracture involves
the entire thickness, or
any table of the skull

19. FISSURE / LINEAR #
• Passing over the vault or
skull base.
• Irregular course, no
more than a hair’s
breadth.
• mostly detected at
autopsy, hardly in X-
ray.

20. LINEAR fractures
They are named according to their location:
1) Hair-line fracture: if the occur in the vault of
the skull
2) Basilar :if occurred in the skull base
3) Diastatic fracture: if they run along suture lines
of the skull.

21. Mechanism………linear #
• When a blow is struck on the side of the head is
free to move, the fracture start at the point of
impact & runs parallel to the direction of force.
• If the head is well supported at the time of struck,
fracture may start at the counter pressure (bilateral
impact…..# in vertex or base).
• Line of fracture runs parallel to the axis of bilateral
impact.
• Often red fracture line but usually no haemorrhage.

22. Mechanism and location of fissured fracture
(MLI) accidental Vs homicidal
• Head injury by fall – situated at the level
of hat-line.
Eg; 1. moving head have a forcible impact with fixed
hard surface…RTA
2. Knocked down to the ground by accident / in
assault
• Head injury by blow ( assault ) – above
the level of hat-line.
Eg ; Hard blunt object having large striking
surface like wooden plank.

23. Depressed fractures

24. DEPRESSED # / Fracture ALa
Signature
• A portion if the fractured bone is driven
inwards to a distance equivalent to the
thickness of the skull table.
• The pattern of fracture reflects the type of
weapon used (signature of the weapon
over skull)

25. Causes- signature #
• Heavy weapon with
smaller striking surface
Example; Hammer, axe,
sharp stone or chopper.
• Sometimes involve the
outer table only.

26. Signature # ( M L I )
• The part of the skull
which is first struck shows
maximum depression,
• heel end of the axe blade if
touches first it produce more deep
cut than its toe end on skull
• Position of victim &
assailant at the moment
• and manner of application
of violence can be
assessed.
Heel end
Toe
end

27. Depressed fractures
• Linear # may radiate
from the depressed #,
indicating the
direction of force
Direction
of force

28. Elevated fracture

29. ELEVATED #
• One end of the fractured segment is elevated over the
surface of the skull & other end may be depressed into
the cranial cavity.
• A blow from a heavy sharp weapon which elevates the
fractured skull by lateral pull of the weapon while
retrieving it.
• Associated with the injury to the dura also

30. Elevated fracture

31. Comminuted fractures
(reduced to minute fragments)

32. Comminuted fracture

33. COMMINUATED #
(reduced to minute particles or fragments)
• Spider web / Mosaic fracture.
• Two or more intersecting lines of fracture
dividing the bone into three or more
fragments.
• When there is no displacement of the fragments it resembles
a spider’s web or mosaic pattern.
• Significant force striking over a broad surface
of area
• Crushing head injuries

34. Comminuted……..
• Vehicular accident
• Fall from a height on a hard surface.
• Repeated blows by weapon with a large
striking surface (iron bar or poker, thick stick)
• It is a complication of fissure # & depressed #

35. Puppe’s rule -
order/sequence of
fractures
1,2,3 are
sequence of
application of blunt
force , causing fissured
fractures of the skull.

36. PUPPE’S RULE…….CONT’D
• The fractures from the 1st injury develop normally, while
those caused by subsequent injury are stopped where
the structure of the skull was already been deployed.
The force of 2nd impact after a while
transmitted along the fractured line of first
impact.
• Puppe’s rule applies when two or more blunt force
injuries with intersecting fracture lines are visible.
• The pattern of radial # lines sometimes allow the
determination of the sequence of the gun shots

37. POND # / INDENTED #
dent

38. POND # / INDENTED #
• Smooth concave dent resulting from in-buckling of the
skull.
• Occurs only in the skulls of infants or children due to
pliability (< 4yrs). Ping-pong #
• Inner table is not fractured.
• Periphery of the dent may show fissure fracture.
• Brain & meninges are not damaged.
• Caused by :- Obstetric forceps,
fall of rounded smooth stone on head

39. Gutter fracture

40. GUTTER #
• Part of thickness of the skull is
removed to form a gutter.
• Caused by oblique bullet
wound or tangential cut by
sword/ chopper
• Associated with irregular depressed #
of the inner table of the skull.
• The dura mater & brain may
be torn.

41. DIASTATIC # / SUTURAL #

42. DIASTATIC # / SUTURAL #
• Separation of the sutures due to a blow on the head
with blunt weapon.
• Occurs only in young children
• m/c suture involved – sagittal suture.
• May occur alone or associated with fissure #.
• In traffic accidents, increased intracranial pressure resulting in
splitting of the sutures

43. perforating fracture
Firearm entry and exit wounds-

44. PERFORATING #
• Caused by firearms or pointed tip
weapons (dagger, knife,
axe).
• Weapon passes through
both table of the skull
leaving more or less
clean cut opening.
• The size & shape
correspond to the cross
section of the weapon
used.

45. Basal skull fractures

46. Basal skull fractures

47. Basal skull fractures- mechanism
• Basal fractures may be produced by –
• 1) Direct force at the base of skull
• 2) General deformation of the skull wherever
the forces applied.
• 3) Extension from the vault.
• 4) Indirect force from spinal cord or face to the
base.

48. Ring fracture

49. Ring fracture

50. RING # / FORAMEN #
• Type of fissure # at the base of
the skull around the foramen
magnum & separating the skull from
the spine.
• fracture line, passing around 3-5 cm
away from foramen magnam.
• through sella turcica…petrous
ridges, middle ear and
• passing backwards and joining into the
posterior fossa.

51. Ring fracture- mechanism
-mainly through transmitting force
• Fall from height & landing through feet or
buttocks- transmitting force from below
upwards through spine
• A severe blow to the vertex.
• A forceful blow underneath the chin- boxing.
• Sudden violent turn of the head on the spine.

52. Hinge fracture/motor cyclist fracture

53. HINGE # / TRANSVERSE #
• Fracture line extends across the basal skull
from one petrous bony ridge to the contra
lateral side through sella turcica.
• Base of the skull completely splits in
to two halves( anterior and posterior)
due to side impacts.
• Creating a hinge (nodding face sign).
• Motorcyclists fracture.

54. # OF CRANIAL FOSSAE-
anterior,
middle and posterior

55. Fractures
of
anterior,
middle,
and
posterior
cranial
fossae(red
line)

56. # Of Anterior Cranial Fossa
• Due to direct impact.
• # of orbital or cribriform plate may be due to
contre coup injury.
Clinical features–
• Epistaxis
• CSF rhinorrhea
• Anosmia
• Black eye- raccoon’s eye
• Carotico cavernous fistula

57. Raccoon eyes – basal skull #
(roof of the orbits #)
Bilateral black eye raccoon

58. # OF MIDDLE
CRANIAL FOSSA
• Due to direct impact behind
the ear or crush injury to the
head.
Clinical features
• Battle’s sign – brusing or
ecchymosis over the mastoid
process in the line of posterior
auricular artery.
• CSF otorrhea
• Hemo-tympanum
• Ossicular disruption &
conductive deafness.
• VII & VIII nerve palsy.
Battle’s sign

59. # OF POSTERIOR CRANIAL FOSSA
• Due to direct impact on the back of the head.
Clinical features
• Blood & CSF through mouth
• Accumulation of blood over the nape of the neck.
• Halo or ring sign :- blood from head injured
patients may mix with CSF & mask the leaking
site.
• If the mixture is placed on filter paper there will
be a central area of blood with an outer ring of
halo

60. Halo or ring sign

61. Basal skull
fracture
Clinical features
1-ENT BLEEDING
Ear, nose throat
bleeding
2-CSF rhinorrhea
3 black eyes
4.battle’s sign
5.nodding face sign

62. Basal skull fracture

63. EXPRESSED # - bomb blast
• Massive fragmentation
or shattering of skull,
where some pieces
may be found
outside the
head.
• Due to bomb blasts,
• close range firearm
injury.

64. BLOW OUT #
• Blunt trauma to the eye …...
• forces are transmitted through the
globe….
• .to the bony orbit……
• causing # of the orbital
walls.
• Tear drop sign :-
• m/c medial wall & floor of the
orbit get fractured…....
Herniation of periorbital
fat & inferior rectus muscle…. Into the
maxillary air sinus.

65. Blow out # - tear drop sign
• Radiographically a
• polypoid or teardrop
shape soft tissue mass
• seen in the roof of
maxillary sinus

66. COMPLICATIONS OF SKULL #
• Injury to the brain.
• Intra cranial Hemorrhages (middle meningeal artery …m/c).
• Infections – brain abscess, septicaemia
• Traumatic epilepsy.
• Shock.
• Fat & bone marrow embolism.
• Oedema and pressure effect
• Brain Herniation, Severe dysfunction of vital
centres, Coma, death.

67. complications…….
• The risk of post traumatic epilepsy is 15%
• Depressed # associated with scalp laceration extending through
pericranium and
• compound fractures are -More prone for
infection
• Depressed # associated with dural laceration and penetrating
fractures- prone for brain injury and infections

68. IMAGING IN SKULL FRACTURES
. Radiography
. Computed Tomography
. Magnetic Resonance Imaging
. Ultra sonography
. Nuclear Imaging
. Angiography

74. Thank
you