by Dr Barry Marks DC, Car Accident Chiropractor
Surprising Car Accident Injury Study from Japan Shocks Auto Insurance Industry
A little known study conducted in 2001 in Japan by Hijioka, Narusawa and Nakamura in Archives of Orthopedic Trauma Surgery studied 400 auto accident victims of various ages and levels of vehicle damage and compared their treatment duration.
Japanese Car Accident Whiplash Treatment Study:
The study disqualified auto accident victims exhibiting nerve or bone damage. The researchers only considered those injuries involving damage to the muscles and ligaments due to car accident trauma. In the US, specialists realize that “whiplash-type” injuries also involve damage to joint linings, discs, nerves and bones. So the study is narrowed to what we would consider mild to moderate injuries. Grades I-II in the Croft grading system. In reality, the study would have shown even more dramatic findings had the more injured grades III and IV been included. Typically, they take considerably longer to become stabilized.
Equating Car Accident Vehicle Damage and Treatment Duration:
Seasoned whiplash experts were not shocked by the results of the study. In fact, it validated what specialists in the field have said for years: vehicle damage does not equate with bodily injury in a linear fashion. However, this study sent a chill through the bones of auto insurers and defense attorneys who make a living from minimizing victim’s injuries. It’s a well known trope to anyone who has been injured: no crash, no cash. Auto insurers have long maintained that occupants cannot be injured unless the car shows significant damage. This, despite the scores of studies proving otherwise.
What this Japanese whiplash study highlighted was two main groups accounted for the longest treatment durations; namely, crashes that involved no damage at all to the bumper and crashes where one half of the car was damaged (rear bumper, trunk lid and either fender damage or frontal damage). The highest total treatment duration was found in the “no vehicle damage” group.
If that wasn’t bad enough news for the auto insurance industry, the results showed the victims with completely destroyed cars had the shortest treatment duration. Crash experts have long maintained that crashes involving no crumpling or deformation of the vehicle passes on more damaging kinetic energy to the occupants. It actually makes sense when you look at it rationally. Energy inputted into your vehicle is bled off by deforming metal and plastic. If it doesn’t deform then more energy is left over to travel through the chassis, into the seat and then into the occupant’s body.
Conversely, while big crashes appear gruesome seeing so much vehicle destruction, much of the energy is dissipated into the vehicle carnage and less to the human occupant.
Considering Occupant Age and Whiplash Treatment Duration:
The lowest treatment duration group were those victims under 20 years of age. The group aged 70 and above fared the worst. Again, this makes sense. Younger more resilient victims can absorb more energy, while older, stiffer, possibly already arthritic spines do not have the capacity to withstand forces of whiplash well. We also know that in general older folks take longer to heal and regenerate tissue compared to younger people. The aged groups in the middle, age 30-40 and 50-60 took approximately the same time to recover.
Updating Risk Factors for Prolonged Car Accident Whiplash Treatment Duration:
This Japanese whiplash study improves our knowledge of risk factors regarding whiplash treatment times. It proves the highest risk for prolonged whiplash treatment are:
- No vehicle damage
- One half of car damaged
- Age >70
- Age 30-60
This is one more important research study that shows the point that vehicle damage does have a correlation with treatment duration, but that it is not what auto insurers have lead people to believe. The true take away from this information is:
“You are Likely to be Injured Even When Your Car Isn’t”