[Low back pain: from symptom to chronic disease].

In several prospective studies it has been demonstrated that psychological factors are better predictors of low back pain than biographical or medical factors. The most elaborate model for the development of chronic low back pain is the model of fear avoidance. The essential feature of this model is that exaggerated negative orientations towards pain ("pain catastrophizing") lead to fear of movements and the belief that movements will lead to more pain. The result is the perpetuation of avoidance behavior. This leads to inactivity, reduced mobility, increased disability, and increased anger, demoralization, anxiety, and depression. From fear avoidance models several principles for the therapeutic management of pain can be derived. Therapists have to be aware of the powerful effects of anticipating processes which can give rise to fear of pain, amplifying the intensity of pain, and consequently result in avoidance behavior. On the other hand, reduction of uncertainty via adequate information about the non-serious nature of back pain disorders may lead to an adequate confrontative pain behavior, less emotional arousal and more useful coping mechanisms. In particular, the uncritical use of widespread back schools has to be looked upon carefully for pronouncing avoidance learning. For chronic pain, therapy must include mechanisms from the treatment of phobias in which pain behavior is looked upon as the result of a phobic process.