Transportation Injuries Overview

Transportation Injuries

• Transportation injuries are a significant concern, particularly in motor vehicle accidents.
• Autopsies play a crucial role in investigating motor vehicle accidents.
  • Determining the cause of death
  • Confirming that death resulted from accident injuries
  • Assessing the extent of injuries
  • Identifying underlying diseases contributing to the accident
  • Detecting potential criminal activity
  • Establishing identification of a body (especially burnt or mutilated)
• Common causes of motor vehicle accidents include:
  • Impaired consciousness (e.g., alcohol or drug use)
  • Natural diseases (e.g., heart disease, epilepsy, diabetes)
  • Speeding, driver fatigue, or carelessness
  • Vehicle defects (e.g., brake failure)
  • Environmental factors (e.g., rain, wind, poor road conditions)
• Factors affecting injury severity and mechanisms:
  • Vehicle speed
  • Vehicle characteristics
  • Vehicle mechanical condition
  • Victim's age and physical build

Dynamics of Vehicular Injury

• Tissue damage is caused by changes in movement (acceleration/deceleration).
• Constant speed, no matter how high, does not affect tissue damage.
• Damage depends on the force applied per unit area.
• Frontal impacts cause violent deceleration; rear impacts accelerate the vehicle and occupants, sometimes resulting in sideways impacts or rollovers.
• A significant proportion (60-80%) of crashes involve frontal impacts. A smaller percentage (6%) involve rear impacts. The remainder include side impacts and rollovers.

Patterns of Non-Pedestrian Injuries (Vehicle Occupants):

• Frontal Impact (Driver):

  • Unrestrained drivers first slide forward, impacting their legs and facial areas.
  • The body then bends across the steering wheel.
  • The head strikes the windshield or the vehicle's bonnet, potentially getting ejected
  • Secondary injuries include intrusion of structure components into the passenger compartment, impacting the driver's feet and legs.
  • If unrestrained, drivers can be ejected sideways during a rollover.

• Rear Impact (Driver):

  • Unrestrained drivers can experience violent acceleration and hyperextension of the neck, followed by hyperflexion—causing whiplash injuries if no head supports exist

• Side Impact (Driver):

  • Injuries depend on the extent of intrusion in the driver's door, with further damages to the body if extreme force exists.

• Injuries to the driver not wearing a seatbelt or airbags:

  • Abrasions, lacerations, broken bones (from feet to femur and hip dislocations.)
  • Steering wheel and other components injuries; ruptured liver (50% of cases), ruptured spleen (36%), bruising of lungs, broken ribs, and sternum- which can cause complications such as pneumothorax, hemothorax
  • Numerous face injuries from hitting the windshield; lacerations that could be V or sparrow shaped.

Injuries to Motorcyclists

• Motorcyclists have a significantly higher risk of injury and death than drivers.
• This is largely due to the rider falling to the ground and often suffering severe head injuries, accounting for about 80% of motorcycle fatalities.
  • Wearing helmets is obligatory in most places to mitigate these hazards.

Common Complications in Injury Cases

• Common forms of injury are:
  • Basal skull fractures (often seen as a transverse crack)
  • Damage to the area around ear, nose, pharynx
  • Injuries including fracture of the skull, intracranial hemorrhage, brain damage.
  • Dislocation of joints such as altanto-occipital
  • Ruptured aorta (especially from pendulum effect, in the region where the aorta is attached to the spine)

Autopsy Procedure in Road Traffic Accidents

• The general autopsy procedure is maintained, with close scrutiny on:

  • Establishing the victim's identity.
  • Examining clothing to identify any abrasions and match them with injury location or vehicle aspects.
  • Thorough external examination of the injuries. The dimensions of these injuries are measured and scrutinized, as they can help with the identification of the colliding car.

• Additional autopsy procedures:

  • Observing the presence of underlying diseases such as old/recent cardiac disease and cerebral lesions - important to determine if these contributed to the accident.

Sample Collection and Laboratory Examination

• Blood samples are collected and analyzed to test for alcohol/drugs.
  • DNA fingerprinting may be necessary for 'hit-and-run' accidents. In these situations, blood, hair, and other samples are collected to identify the offending vehicle.

Pedestrian Injuries:

• Unlike vehicle occupants, pedestrian injuries are acceleration/deceleration-driven.

• Common pedestrian injuries include being struck by the front portion of a vehicle.

• Pedestrian injuries are divided into primary (initial impact) and secondary (contact with the ground)

• The most common driver in fatal road accidents is the driver themselves. The driver or front passenger frequently sustain more severe accidents.

• Typical injuries are often to the lower limbs (legs) with visible abrasions/lacerations typically noted. Tibia injuries are also common (fractures often wedge-shaped, showing direction of impact.

• Head injuries from impact with the windscreen, roof, or pillars are frequent.

• Soft tissue injuries—including muscle lacerations and crushing injuries—can also result from running over or contact with any vehicle component.

• Patterns of injuries are important in identifying a vehicle.

• Measurements are required to assess the site and character of different abrasions/lacerations and injuries caused by vehicular impact which can help determine the vehicle dimensions.