Study Design. The literature on psychological factors in neck and back pain was systematically searched and reviewed.
Objectives. To summarize current knowledge concerning the role of psychological variables in the etiology and development of neck and back pain.
Summary of Background Data. Recent conceptions of spinal pain, especially chronic back pain, have highlighted the role of psychological factors. Numerous studies subsequently have examined the effects of various psychological factors in neck and back pain. There is a need to review this material to ascertain what conclusions may be drawn.
Methods. Medical and psychological databases and cross-referencing were used to locate 913 potentially relevant articles. A table of 37 studies was constructed, consisting only of studies with prospective designs to ensure quality. Each study was reviewed for the population studied, the psychological predictor variables, and the outcome.
Results. The available literature indicated a clear link between psychological variables and neck and back pain. The prospective studies indicated that psychological variables were related to the onset of pain, and to acute, subacute, and chronic pain. Stress, distress, or anxiety as well as mood and emotions, cognitive functioning, and pain behavior all were found to be significant factors. Personality factors produced mixed results. Although the level of evidence was low, abuse also was found to be a potentially significant factor.
Conclusions. Psychological factors play a significant role not only in chronic pain, but also in the etiology of acute pain, particularly in the transition to chronic problems. Specific types of psychological variables emerge and may be important in distinct developmental time frames, also implying that assessment and intervention need to reflect these variables. Still, psychological factors account for only a portion of the variance, thereby highlighting the multidimensional view. Because the methodologic quality of the studies varied considerably, future research should focus on improving quality and addressing new questions such as the mechanism, the developmental time factor, and the relevance that these risk factors have for intervention.
Although spinal pain is quite common, a sound scientific explanation of its etiology, particularly its development into a chronic problem, has been elusive. One clarification shows that a pain problem has many facets and therefore cannot be explained easily in simple models. 72 A multidimensional approach to the understanding of pain that incorporates a biopsychosocial model has gained acceptance, and it currently places psychological factors firmly in the realm of pain research and practice. 65,71 Indeed, psychological factors were long believed to be associated with chronic pain, 17,20 but recent data has focused on psychological factors even in acute and subacute pain. 5,10,45
Research on psychological factors in neck and back pain has been complicated by three factors. First, the reciprocal nature of psychological factors and spinal pain has created a which came first, the chicken or the egg dilemma. 42,65,73 Second, a variety of theoretical notions exist on how psychological factors may influence pain, so there is an extremely large number of potentially interesting variables to research. 17,32,40,47,52,63-65,69 Third, the temporal aspect of pain development is essential because factors may have different effects at different time points, thus creating innumerable combinations of a given risk factor's effect in relation to the developmental stage (e.g., acute, subacute, recurrent or chronic).
Despite the methodologic challenges, several review articles are available already. 3,15,18-21,28,30,33,34,42,43,60,62 65,66,73 However, these have considerably different aims and methods. They have identified different articles, and none constitutes a systematic review.
Given the vast number of reports being published, there is a need to include the latest literature. The methodologic quality of studies included in a review also is a concern. The most frequently used design in this area is the cross-sectional approach, but unfortunately it has a number of weaknesses that limit conclusions. A more efficacious design is the prospective or longitudinal design by which a group is followed over time, and subjects developing a characteristic (episode of back pain) are compared with those who do not.
The purpose of this study was to review the evidence concerning psychological factors in neck and back pain. Therefore, the literature was searched systematically and a table of prospective studies constructed. The following specific questions were posed:
1. Is there evidence that psychological factors are involved in the etiology of these pain problems?
2. Has it been shown that psychological variables are involved in the development of chronic problems?
3. Which variables are important in the etiology and development of spinal pain problems?