Primary impact injury, secondary impact injury, secondary injries, sparrow foot mark injury, air bag injury, railway injuries, aircraft injury.

1. ROAD TRAFFIC INJURY
by
Dr Mohd Kaleem Khan
Assistant Professor
Department Of Forensic Medicine
JNMCH AMU Aligarh

3. • The road traffic accidents,
injuries may be sustained to.
1. Pedestrian .
2. Cyclist / motorcyclist.
3. Occupants of a vehicle.

4. Traffic Accidents
• A large variety of injuries are sustained by
persons involved in traffic accidents..
• A traffic collision, also known as a traffic
accident, motor vehicle collision, motor
vehicle accident, car accident, automobile
accidents, road traffic collision, road traffic
accident.

5. 1. INJURIES TO PEDESTRAINS
Three patterns of injury are often seen.
1. Impact Injuries- when vehicle strike the victim
2. Secondary Injuries- due to victim falling on
ground or striking any other stationary object
3. Run-over Injuries- d/t vehicle running over
some part of victim

6. Impact Injuries
• Primary Impact Injuries:
d/t initial impact of vehicle
Projections of vehicle may cause specific injuries
e.g. bumper fracture (# of tibia & fibula of one or
both the legs)
Height of pedestrian often determines site of injury
• Secondary impact injuries:
Subsequent impact with the same vehicle

7. Secondary Injuries
– Usually found on parts opposite to primary impact
– Most pronounced over the unclothed areas of the
body
Run-over Injuries
– Severity of injury will depend upon the part of body
run over and weight of the vehicle.
– E.g. degloving injury, tyre marks, burns, avulsion
etc.

9. I. In Primary Impact injury:-
• These are the injuries caused by vehicle when it first
struck and Hit the person whether crossing the road
from one side to the other side or walking with or
against the traffic.
• The importance of primary impact injury is that the
body of victim may bear design / pattern of the part
of vehicle in form of imprint abrasion pattern
bruised.

11. Common parts of vehicle which may struck or
hit a person includes..
1. Bumper
2. Wing
3. Grill
4. Head Light
5. Fender
6. Radiator
7. Door handle

12. The body part which bears the injury depends
upon the position of the person such as
1. Was the pedestrian struck by front of Car/Vehicle?
2. Was the pedestrian struck by side of Car/Vehicle?
3. Was the pedestrian standing on road?
4. Was the pedestrian walking on road?
5. Was the pedestrian lying on road?
• If the vehicle was braking violently at the movement
of impact, the font end of the vehicle dips down an
the legs get injured at a lower level.

13. The injury comprises of damage to skin and
fracture of bone (k/w as Bumper fracture).
• The Bumper fracture usually involves Tibia. The
fracture is wedge shaped with base of triangular
fragment indicating the site of impact and apex
pointing the direction of vehicle.
• Frequently Bumper injuries are at different level
of the two legs or absent on one leg, which
suggest that the victim was walking or running
when Struck.

15. • Frequently Bumper injuries are at different level of the two legs
or absent on one leg, which suggest that the victim was walking
or running when Struck
• In children the bumper usually produces fracture of the femur.
• If bumper injury are at the same level on both legs then it means
the person is standing.
• The level of bumper injury (i.e the height of injury from ground
level) varies with height of bumper of different vehicle. It means
than the offending vehicle can be identified.

16. • At impact against the headlamp or mudguard
may result in fracture of the pelvis or fracture
dislocation of the sacroiliac joint.
• The findings of primary impact injury are
important to find out the relative position of
pedestrian and vehicle and kind of vehicle
involved in the Incident.

17. II. In Secondary Impact Injury
• After sustaining primary impact of injury, the
person may be lifted off the ground and thrown
of the vehicle.
• Thus these secondary impact injuries are resulted
from the impact of body of a person and the
vehicle for a second time.
• Here the person strike to windshield or bonnet or
placed on the top of car/ vehicle.

19. After the second impact injuries, the victim will
be thrown on the ground.
– Extensive abrasions, bruises and laceration may be
seen.
– Some times pedestrians are ‘run over’ if knocked
down by the vehicle.
– This will tend to occur if the pedestrian’s center of
gravity is lower then the impact side or scooped-up
victim being run over by other vehicle.
– Injuries are variable, depending on the area of the
body involved.

20. The weight of the vehicle and the surface area of
the contact. There may be:
1. Tyre trade marks marks over the unclothed
or clothed areas on one surface of body with
graze like abrasions on the opposite side of
body.
2. The head may be crushed causing gross
distortion and externalization of the brain and
severe injuries my occur to the chest, pelvis &
abdomen.

21. iii. Compression of the chest may result in multiple
rib fractures, causing a ‘flail chest ’ with
rupture of internal organs along with the
fracture of spine, sternum & ribs.
iv. Burning and singeing of skin and hair resulting
from discharge of hot exhaust

22. Flail Chest:-

23. III. Secondary Injuries
• These are the injuries that occur after second
impact injuries when the victim is thrown off
the vehicle on the ground.

24. • Here the victim sustain secondary injuries from the
ground. Head injury is more common though injuries
to other part may occur.
• Some times the victim may be run over by the same
vehicle and another vehicle.
• Brain damage is frequent without any associated skull
fractures.
• Fracture of the skull and ribs due direct contact with a
surface, and fracture of spine due to hyperflexion or
extension may be seen.

25. • Fracture of the limbs are common but apart from toes
of the legs.
• Usually it is very difficult to classify the injuries as
Primary impact, secondary impact or secondary
injuries.
• In pedestrian accidents, the common cause of death is
head injuries and fracture dislocation of cervical
spine.
• Injuries to the chest and abdomen are minimal or
absent.

26. 2. Injuries by motorcycle & cycle:-
• Injuries sustained by motorcyclist are much
more serious then car travelers because:-
1) Inherent instability of two wheeler.
2) Unprotected and lack of protective gear.
3) Rush and negligent driving
.

27. The common causes of motorcycle accidents are
1. Alcohol,
2. Drugs,
3. Environmental factors,
4. Reckless driving and failure by drivers of Cars to
see the motorcycle

28. .
5) The most common cause of motorcycle fatality is running of
road.
6) Most injuries are due to ejection from the vehicle into the
roads, due to high speed and instability of the vehicle.
7) Primary injuries are mostly open fracture of the Tibia and
Fibula.
8) Secondary injuries are mostly fracture of the Skull, Ribs &
cervical spine, as well as contusions of the Brain.
9) There are graze abrasions due to sliding across the road.

29. :Any part of body may sustain injury but regions are
more affected and are:
Head:-
1. Injury sustained to head is common in motorcyclist followed by
thoracic and abdominal region.
2. Fall on road surface and sustaining injury to lateral part with
fracture of temporo – parietal bone is very common.
3. Fracture occurring in skull of motorcyclist can be summarized
as:

31. Fall on side with side impact to head causes basal
skull fracture especially hinge type .
Impact on face causes fracture of facial skeleton.
Impact on forehead causes sagittal fracture of base
of skull.
Impact on chin causes mandibular fracture.
Impact on crow of head by fall may cause ring
fracture.

32. 4. Injuries by occupant of a vehicle:
– Driver.
– Ejection of driver and passenger
– Door often burst open.
– Unbelted rear seat occupants.

33. – Tissue injury is caused by a change of rate of
movement.
– A constant speed, however rapid, has no
effect whatsoever as is evident from space
travel or the rotation of the earth
– It is the change of rate that is traumatic – that
is, acceleration or deceleration.

35. The Driver And Passenger Injuries
can be:-
1. Front impact crash:
This happen when one car strikes
• Another car head- on or
• Strike a stationary object,
• Like an electric pole/ tree

38. • Unrestrained Driver
• First slides forwards so that his legs strike the
fascia/parcel-shelf area, and his abdomen or lower chest
contacts the lower edge of the steering wheel.
• The body then flexes across the steering wheel and
begins to rise.
• The heavy head goes forwards, and there is flexion of
the cervical and thoracic spines.
• The upward and forward component causes the head to
strike the windscreen, the upper windscreen rim or the
side pillar.

39. • The windscreen is often perforated by the head or face,
And the whole body may be ejected through the broken
glass, to land on the bonnet or even on the roadway
ahead.
• The intrusion of structural parts into the passenger
compartment
• The engine or front-wheel assembly may be forced back
into the seating area, intruding upon the driver.
• The roof or front corner pillar (the so-called ‘a’-frame)
may cave in on top of the driver

40. • The steering column may be forced back to ‘stab’ or
crush the driver’s chest or abdomen.
• Column, engine, or gearbox intrusion may be to force the
floor up and backwards against the driver’s feet and
legs.
• Pedals cause transmitted force up the legs and into the
pelvic girdle
• Door may burst open and the driver, if unrestrained,
ejected sideways onto the road, especially in a crash
that has a roll-over component.

43. • Rear impact, the driver is violently accelerated
• If no rigid head restraint is fitted to the seat, severe
hyperextension of the neck occurs, causing ‘whiplash’.
• In side impacts, the injuries depend upon the amount of
intrusion of the driver’s door and side panels.

44. The driver receive.
1. Fracture of wrist and arms occur when driver brace
himself against the steering wheel.
2. The fracture or dislocation of
1. Tibia, fibula &
2. Pelvis
3. Impact from pressing on the break and clutch pedals.
3. Impact of the knees against the dashboard
1. Fracture of the tibia, fibula, femur & pelvis.

45. 1. Severe impact against the windshield pillar may cause
1. Avulsion of the skin of the forehead,
2. Basilar skull fractures,
3. Closed head injury and
4. Fracture or dislocation.
2. Steering wheel impact injury: The steering wheel may
cause
1. Fracture Of The Jaws And
2. Facial Bones.
3. Abrasions, Bruises And Contusions Of The Chest Or
4. Bilateral Rib Fracture.
5. Laceration Of Spleen & Liver May Be Seen.

46. Front Seat Passenger/
1. Whiplash injury:
2. “Sparrow Foot marks”.
3. injured against internal fittings, like
1. Doors,
2. Handles or
3. Ejected through burst-open doors.

48. 2.Rear impact crash:-
• Low velocity rear impacts
– cause whiplash injury
– Neck fractures are rare.
• A high velocity rear impact crash can deform
and rupture the gas tank with ignition of the
fuel.

49. • In a rear impact, the driver is violently
accelerated and, if no rigid head restraint
is fitted to the seat, severe hyperextension
of the neck occurs, often followed by the
sequence of deceleration events when the
car is cannoned into the vehicle or other
obstruction in front, causing the popular, if
inaccurate name of ‘whiplash’.

50. Whiplash injury:-

52. 3.Side impact crash:-
• The vehicle strikes on the
– Side of another vehicle or
– Skids sideways into a fixed object.
– Injuries are often severe, because
– The side of a car has a thin metal wall door and
– No other components to absorb the force of impact.
I. Dicing injuries may occur which are superficial cuts
of the skin caused by fragments of tempered glass.

54. II. They are
– Linear,
– Right angel or
– V- shaped laceration
– Seen typically on the face, forehead and arms
– On the right side of the driver and left or
– Right side passenger.
III. Other injuries
– Cervical spine fracture ,
– Fractured ribs,
– Contusions, lacerations and
– Explosive tearing of the lung on the right side of the impact
common.

55. III.In the abdomen,
– A lateral impact on right causes laceration of the
right lobe of the liver and right kidney.
– The pelvis may be fractured from an impact on
the either side.

56. 4.Roll-over crash:-
• A roll over crash, the occupants receive the surprisingly
moderate impact, if the vehicle is not brought to a
sudden stop.
– The crashing of different sides of the vehicle absorbs the
forces of impact.
– If the passenger compartments remains intact,
– The belted occupants frequently survive the crash.

57. • Non belted occupants are involved into two types of
injury:
 Tumbling around inside and striking
 Ejection out from the vehicle.

58. Role of seat belts and air bags:-
• Numerous safety features such as
– Safety belts,
– Air bags,
– Collapsible steering columns,
– Softened interior dashboard and
– Anti lock breaks
• The air bag system reduced chest and facial trauma, in
those individuals not using seat belt.

61. • Wearing seat belts reduces the risk of fatalities to
front seat occupants by 45% since.
i. Injuries are of less severity, except whiplash injury.
ii.Probability of severe head injury is lower.
iii. Probability of being ejected from the vehicle is lower.
iv.There are fewer fatal/ major injuries to head, neck, chest &
abdomen.

62. • Lap belts can produce tears of the mesentery,
omentum and laceration of the bowel .
• Shoulder belt may produce a linear abrasion
running downward and medially on the right
side of the driver and left side of front seat
passenger.
• Although seat belts reduce mortality, they cause
a specific pattern of internal injuries.

63. Injury By Seat belt