When neck pain from a whiplash injury occurs and becomes chronic is it the pain that causes disability in a direct chain of events? Or is there some other indirect factor or variable that links pain with disability? In this study, researchers from the George Institute for Global health in Sydney, Australia take a closer look at fear of movement as the possible mediating (indirect link or cause) between neck pain after whiplash injury and disability.
Fear of movement (also known as fear-avoidance behavior or FAB) is fairly common after whiplash injuries. Some people respond to pain with anxiety about their pain and fear about what it might do to them. They start to catastrophize the pain (build up negative thoughts in their minds about pain).
Before you know it, they are no longer moving freely out of fear that certain movements and actions “might” cause pain. They stop moving and start avoiding activities they previously enjoyed freely. Over time they become deconditioned and even disabled.
The group of patients (205) included in this study had all been involved in a motor vehicle accident. The accident occurred within four weeks of the study. They each reported ongoing (chronic) neck pain. They each filled out four separate surveys measuring pain, function, fear levels, and questions about physical and mental health. These test measures were completed within four weeks of the accident and again three months after the accident and one final time six months after the accident.
Special surveys just to measure fear avoidance beliefs have been developed and tested. For example, the Tampa Scale of Kinesiophobia, Pictorial Fear of Activity Scale, Fear Avoidance Beliefs Questionnaire, and Photograph Series of Daily Activities are in use by many health care professionals who work with people who have chronic low back pain.
Testing patients with post-whiplash (neck) pain using these same tools is a fairly new focus of research. It is not possible to assume that neck pain after whiplash influences (fear-avoidance) behavior and leads to disability just because this relationship has been shown for low back pain. A separate analysis is necessary, which is why this study was done.
After reviewing all the data and making comparisons, they found that fear of movement can explain about 20 to 40 per cent of pain-related disability. That means in 20 to 40 per cent of the patients, relieving pain did not reduce levels of disability.
And for the remaining 60 per cent of the patients, there is either another factor responsible (besides fear of movement) or perhaps several factors present at the same time. These other factors could be things like the presence (and severity) of other physical problems, mental health issues, or social, economic, or cultural differences.
A second observation was the fact that in this group of 205 patients, there was not an increase in pain-driven disability over time. In other words, their pain and disability didn’t get worse as time went by.
A third and final conclusion from this study was the idea that there isn’t a direct cause and effect between fear-avoidance behavior and disability. It looks more like there is a relationship of some type between pain, fear of movement, and disability but the word association is a better descriptor than cause.
What are the clinical implications of these findings? Some, but not all, patients with whiplash associated disorders can be helped by therapy to reduce fear avoidance beliefs and behaviors. Knowing which patients might fall into this category will be the subject of future studies. Other studies are also needed to find out what other factors influence the pain-leading-to-disability phenomenon.
The authors also suggest there is a need to examine the different tools used to measure catastrophizing, fear-avoidance beliefs, and fear of movement. It is possible that one of the many questionnaires in use could be more accurate and reliable than others when given to neck pain patients (compared with back pain patients).
For now, we can say there is a relationship between pain and disability in patients with whiplash associated disorders, and that in a subset of these patients, fear of movement is the key factor at play. The Fear Avoidance Model used to explain pain and disability in patients with low back pain can only explain 20 to 40 per cent of pain-related disability following whiplash injuries.