Musculoskeletal pain is one of the most frequently reported complaints in primary care. The last decade's research has evidenced the important role of pain-related fear in the maintenance and exacerbation of chronic pain problems. In this article we review the current state of the art regarding the nature, development, and consequences of pain-related fear. We also discuss the implications for therapy, including mass media campaigns, education, exercise therapy, and exposure in vivo. Finally, we propose directions for future research, including the need to tailor treatments to individual patient characteristics, the role of interoceptive conditioning, implications of the context dependency of learning, and the consideration of implicit versus explicit attitudes toward feared painful stimuli.
Keywords: pain-related fear; musculoskeletal pain; exposure in vivo; interoceptive conditioning; interoceptive exposure; mediation
Musculoskeletal pain is one of the most frequently reported complaints in primary care. Approximately 70%-85% of the population will experience musculoskeletal pain at some point in their working career (Andersson, 1999). Fortunately, the majority recovers quickly and undramatically. After an acute episode of pain, most patients can return to work within 4 to 8 weeks. After that time, it becomes increasingly unlikely patients will ever return to work (Fritz & George, 2002). For approximately 10% of adults pain persists. Although this group concerns a small proportion of patients, it comprises more than half of allocated resources, causing huge societal costs due to health care utilization and work absenteeism (Boersma & Linton, 2005; Hashemi, Webster, & Clancy, 1998). This calls for an effective treatment regimen for chronic pain. Given the epidemiology of back pain, the easiest way to select patients at risk is based on a "wait-and-see" policy. Patients still suffering from pain after 4 to 8 weeks should receive special attention from health care providers. However, at this point, it may be difficult to reverse the negative consequences of a pathology present for several weeks (Vlaeyen & Morley, 2005). Furthermore, in 85% of the cases of back pain there is no identifiable physical pathology, and it has become apparent that a significant number of patients do not benefit from the identification of physical factors and prescription of traditional medical treatment (Turk, 2005). In fact, pain is a complex, subjective, and multidimensional perceptual experience that is influenced-in its inception and perpetuation-by a wide range of psychosocial factors, including emotions, social and environmental contexts, sociocultural background, the meaning of pain to the person, and beliefs, attitudes, and expectations, as well as biological factors (Turk & Okifuji, 2002). Because most chronic pain research has been conducted in the field of musculoskeletal pain, the focus of the current overview will be on this pain type. Where relevant, findings from other clinical or nonclinical groups will be mentioned.
RISK FACTORS FOR THE CHRONICITY OF PAIN AND PAIN-RELATED DISABILITY
An increasing number of studies show that self-reported pain and disability levels in patients with chronic pain are associated with cognitive and behavioral rather than physical and biomedical aspects (de Jong et al., 2005; Fritz & George, 2002; Keefe, Rumble, Scipio, Giordano, & Perri, 2004; Pincus, Burton, Vogel, & Field, 2002; Turk & Okifuji, 2002; Vlaeyen, de Jong, Geilen, Heuts, & van Breukelen, 2002). In some situations psychosocial factors may be more disabling than the pain itself (Crombez, Vlaeyen, Heuts, & Lysens, 1999; Waddell, 2004). However, this is uncommon because pain is likely designed to capture attention and to interfere with ongoing behavior and tasks (Eccleston & Crombez, 1999).
Based on the former, a list of "yellow flags" was proposed to complement the so-called "red flags," a set of physiological risk factors for long-term disability, such as acute inflammation, fractures, and malignancies. …