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.
It sounds like your therapist thinks this model applies to you. There are ways to test for fear-avoidance beliefs and behaviors. 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 some researchers are starting to take a closer look at measuring fear of movement in patients with chronic neck pain following whiplash injuries.
You may want to ask your therapist to review the results of these tests with you if you have already taken them and that’s how she knows you are experiencing fear-avoidance behaviors. Or, if you haven’t taken any of these tests, this may be a good time to do so to confirm (or rule out) catastrophizing or fear avoidance beliefs in your situation.
If none of these suggestions work for you, it may be time to consider seeing a different therapist. But be prepared for the same approach with another therapist if there is, in fact, a strong influence of fear and anxiety fueled by your pain and affecting your movement.