They say not everyone who has a car accident gets a whiplash injury. But it's my dumb luck to be one of them. I'm not an overly emotional or hysterical person. I usually heal quickly after a cut or other minor injury. So how come, after six months, I still have headaches, neck pain, and jaw pain from the accident? Why me?
Scientists are still scratching their heads over chronic whiplash injuries. They ask the same question: why is it that some people recover just fine, while others go on to develop a chronic problem? In fact, the problem is common enough that it now has a label: whiplash associated disorder (WAD).
Some experts suggest there are risk factors that predict who might end up with WAD. One of those predictive factors is referred to as local sensitization to noxious stimuli. This describes how the nervous system seems overly sensitive and responds faster and with stronger pain signals in some people. The theory is that the nervous system is already pretty touchy either before the accident or right after the injury.
Studies have shown that when the body perceives stimulation as painful, it produces muscle fatigue and weakness. The person who becomes highly sensitive has a lower threshold for pain. Not only that, but the pain spreads to other parts of the body outside the area of injury. The affected muscles have a reduced ability to contract fully and also have reduced endurance (lasting power).
There may be pre-injury factors that set a person up for the development of chronic pain after a whiplash injury. The exact mechanism for how and why this occurs remains unknown. Clearly, there is a decreased pain threshold and increased sensitivity to pressure or other stimulus that is then perceived as pain, but why does this happen?
If patients who are at risk for WAD can be identified early enough, it may be possible to prevent persistent symptoms and preserve muscle function. The result could be a faster return to full function without loss of work capacity.
Future studies will continue to look into this question. Scientists will try to understand exactly what's going on in the nervous system and why some patients seem more susceptible than others to WAD. Identifying predictive patient factors (personal or physiologic) can open the door to finding ways to keep pain signals from escalating in intensity, duration, and frequency. In this way, it may be possible to prevent WAD altogether.