WAD and Widespread Pain
One important aspect about the course of recovery from WAD is whether the neck injury is a trigger for subsequent widespread body pain. This has been suggested from cross-sectional studies, but knowing whether widespread pain came before the neck injury remains unclear from this type of study design. A potential aetiological explanation is a neurophysiological disturbance in the peripheral and central nervous system, which, in some stances, leads to an increased sensitivity to pain in other ‘uninjured’ areas. Another possible explanation for widespread pain is that new tissue damage may result from an altered pattern of movement in the body due to the neck pain. The exact aetiology of widespread pain is that new tissue damage may result from an altered pattern of movement in the body due to the neck pain. The exact aetiology of widespread pain is probably complex and multifactorial, but there are no indications that it would be specific to WAD. It can also occur after surgical intervention or any tissue damage. In addition, large prospective studies on pain of other aetiology have demonstrated that psychosocial factors at work, repetitive strains or other physical strains at work, awareness of symptoms and illness behavior may increase the risk of development of widespread pain. Thus, it seems that biological as well as psychological and social factors contribute to the development of widespread pain.
Prospective studies on WAD and its association with widespread pain are sparse and the evidence is not clear. The results from one study suggest a relationship between the onset of neck pain or other associated symptoms as well as self-perceived injury severity, after an MVC, and subsequent widespread pain. However, age, gender, health behavior and somatic symptoms prior to collision were at least as important. Another study investigated the incidence of onset of more extensive pain during 12 months of follow- up of WAD claimants, and associated factors with such an outcome. In that study, a less conservative definition of widespread pain was used and probably have resulted in higher incidences. The main conclusions were that widespread pain was common over a 12-month period (21%), but most improved over the follow- up period. Female gender, poor prior health, greater initial symptomatology (including pain intensity) and more depressive symptoms were associated with the development of extensive pain. The authors also found that local neck/ back pain, raising the question of the potential cause of widespread pain in other studies.