Last week while driving to work, you were stopped at a red light and glanced in the rear view mirror only to notice a car approaching from behind way too fast. The next thing you remember is the squeal of the tires and a loud crash with an accompanied sudden jolt as your car was propelled forward by the impact. Your initial reaction was one of shock. You wondered, is anyone hurt? How bad is my car damaged? Will there be another hit? Should I get out of the car? I’m going to be late for work!
Within a few minutes, the police arrived and after about an hour of taking statements from the two drivers and a few witnesses, you declined an ambulance ride a nearby hospital for an examination thinking "…this little stiffness and ache in my neck is no big deal." Happy you could still drive your car, you arrived at work an hour and a half late. After reviewing the details of the crash with co-workers several times, you began to notice a headache, your neck stiffening up, and movements becoming limited and painful. After another couple of hours and a few ibuprofen, the pain had increased and you now had a whopping headache. You decided, "I better go see my chiropractor to see if something is wrong."
After the exam and x-rays, your doctor of chiropractic showed you a chart and explained the mechanism of injury that usually occur in a low speed rear-end collision. A couple of things he or she said really hit home in helping you to understand how such a seemingly minor crash can create so much pain.
For example, it is not possible to voluntarily contract a muscle quick enough and "brace" to prevent the acceleration of the head. Upon impact, as the car is propelled forwards, the head initially goes backwards and then when the muscles in front of the neck are stretched to their limits, the head is then "whipped" forwards in a "crack the whip" type of response and all of this takes less than 600-700 milliseconds! Because of the far limits of neck motion being reached during this process, the ligaments that hold the vertebra together are often stretched and/or torn. This can be appreciated on the bending neck x-rays which show one vertebra sliding forwards on the one below and the angle created being greater when compared to the surrounding vertebra.
The second point of discussion that stood out was the fact that your head was rotated at the time of impact from looking in the rear view mirror. This placed your neck at a greater risk of injury because of the twisting motion that occurs during the "crack the whip" process.
Another interesting point: Because there wasn’t a lot of car damage, the shock and force of the impact was not absorbed by crushing metal and that energy was therefore transferred to the contents in the vehicle, including the occupants. That is why your briefcase ended up on the floor and your glasses flew off during the crash.
A fourth point of discussion was made concerning the difference between genders and the degree of injury, as women are more likely to be injured more severely because of the less muscular and sometimes longer female neck. The degree of injury is also at greater risk when there is osteoarthritis already present in the neck. So, if you are a middle-aged female with a long, slender neck with pre-existing arthritis looking in the rear view mirror prior to impact in a rear-end collision, ligament over stretching / tearing is highly probable.
In summary, it is important to obtain prompt evaluation and treatment by your chiropractor as soon as possible following an accident. When time passes without treatment, it is more difficult to bring about a reduction of pain and increased motion and it will generally take longer. Taking medication for pain only postpones the needed process of restoring movement and function to the neck so that should not be the only treatment. In general, a "wait and watch" approach is not wise in these types of injuries.