The Spine Journal 14 (2014) 2679–2681
Commentary
Current evidence on catastrophizing and fear avoidance beliefs in low back pain patients Jens Ivar Brox, MD, PhD* Department of Physical Medicine and Rehabilitation, Oslo University Hospital, University of Oslo, Pb 4950 Nydalen, N-0424 Oslo, Norway Received 1 August 2014; accepted 23 August 2014
COMMENTARY ON: Wertli MM, Rasmussen-Barr E, Held U, Weiser S, Bachmann LM, Brunner F. Fear-avoidance beliefs—a moderator of treatment efficacy in patients with low back pain: a systematic review. Spine J 2014;14:2658–78 (in this issue).
Two systematic reviews published in the present edition of the Spine Journal support that the fear avoidance model (FAM) is important for understanding the prognosis in patients with low back pain [1,2]. This is in contrast to the critics of the FAM in a recent topical review published in Pain [3]. The authors of the latter review suggested replacing the FAM by a multidimensional framework of pain-related disability. Although topical reviews may provide theories and new hypotheses, the aim of systematic reviews is to summarize the best evidence available from empirical studies. Possible disadvantages are that important details may be overlooked and that studies may either not be identified or not analyzed because of narrow inclusion criteria. Particularly for psychological variables, the transformation of beliefs, attitudes, and symptoms into numerical scores analyzed as linear variables is a scientific challenge. Therefore, the results from systematic reviews extracting information from studies using standardized questionnaires should be supplemented by studies using different research methodologies, such as interviews and observation. The initial studies from Vlaeyen et al. [4,5] proposing the FAM used qualitative methods. Findings contributed to a paradigm shift opposing the more common biomedical model for treatment of low back pain.
Little Albert Fear as a phobic stimulus may be traced back to the classic study published in 1920 by the psychologists John B. FDA device/drug status: Not applicable. Author disclosures: JIB: Nothing to disclose. * Corresponding author. Department of Physical Medicine and Rehabilitation, Oslo University Hospital, University of Oslo, Oslo, Norway. Tel.: þ4797702383. E-mail address: [email protected] (J.I. Brox) http://dx.doi.org/10.1016/j.spinee.2014.08.454 1529-9430/Ó 2014 Elsevier Inc. All rights reserved.
Watson and Rosaline Rayner at John Hopkins University [6]. In their experiment with little Albert, aged 9 months, a normally pleasant stimulus was conditioned or learned to be fearful. This study that would have been considered unethical today, provided evidence of classical conditioning in humans. At baseline, the emotionally stable child showed no fear of the white rat, but by introducing a loud sound little Albert started to cry and show fear, which after pairing of the two stimuli turned into distress and avoidance behavior as just the white rat appeared in the room. This experiment has been criticized not just for ethical reasons, but also because there was no control subject and no post experiment in an attempt to reduce fear. A study by Cover Jones [7] published some years later suggests that it is possible to reduce fear and avoidance while repeatedly introducing a pleasant stimulus together with the fearful stimulus. Is it possible to translate this experiment into the FAM? A patient experiencing acute back pain that is aggravated by movement will try to avoid this unless he or she is convinced that it is safe to move. Acute back pain has a favorable prognosis and pain will recover in most patients independent of treatment [8]. The question is why fear and avoidance do not always fade away and in some patients become chronic. Have health-care providers become the conditioning stimulus by restricting the patient’s physical activity? The FAM was proposed in 1983 by Lethem et al. [9]. Later Waddell et al. [10,11] introduced the biopsychosocial model to better understand the failures of strict biomedical informed treatment. In 1993, they published a questionnaire for measuring fear avoidance beliefs (FABs) [11]. The central concept of the FAM is fear of pain. It is debated whether this has to be preceded by catastrophizing. It may be argued that a patient is unlikely to demonstrate fear of pain unless some kind of illness information together with negative affectivity is processed. Sensory, biomedical,
2680
J.I. Brox / The Spine Journal 14 (2014) 2679–2681
emotional, cognitive, and behavioral aspects of pain are associated with physical performance and self-reported disability. It is debated whether the critical factor is pain or the consequences of pain. The FAM proposes confrontation and avoidance as the two extreme responses to pain, of which the former leads to reduction of fear over time. Avoidance leads to exacerbation and maintenance of fear that may generate a phobic state. The purpose of the first systematic review was to examine the importance of catastrophizing as a coping strategy in patients with low back pain [1]. High catastrophizers experienced worse outcome In the present systematic review, 89% of the records screened for inclusion were excluded. This suggests that results are prone to selection bias, but the authors have described the prespecified inclusion criteria in detail and exclusions seem justified. Twelve of the 16 included studies evaluated self-reported outcomes. Most of them found that catastrophizing was associated with pain and disability at follow-up. Five of six studies that applied cutoff values for the total score found that patients identified as high catastrophizers experienced worse outcome compared with low catastrophizers. The pain catastrophizing scale [12], the coping strategies questionnaire [13], and the pain-related questionnaire [14] were used to measure catastrophizing. These scales are only partly validated and the moderate correlation between two of the scales suggests that they are not measuring the same construct. One additional limitation was that the variability of patient scores was low. The discussion highlights the gaps in the literature and makes appropriate recommendations for future research. The article is easy to read and additional information is provided in the appendix. High FAB scores are associated with worse outcome The second systematic review evaluated the influence of FABs on work-related outcome, pain, and disability. Inclusion was limited to randomized controlled trials that investigated nonoperative treatment efficacy. Of 646 records, 78 studies were carefully evaluated, 12 high-quality studies and 5 lowquality studies were included. The authors concluded that in patients with low back pain for less than 6 months there was high-quality evidence that FAB (high scores) was associated with more pain and disability and less return to work. A decrease in FAB was associated with better outcome (moderate-quality evidence). Interventions that addressed FAB were most effective (moderate-quality evidence). In patients with chronic pain findings were less consistent. Perceived psychological and social factors at work were strongly associated with FABs about work in sick-listed back and neck patients [15]. Possible methodological aspects that should be further evaluated in future studies are that the outcome measures applied (FABQ [FAB questionnaire] and Tampa Kinesiophobia Scale) are only
moderately correlated and that cutoff values for high and low scores are debated. In a previous systematic review, we reported that a nonoperative intervention addressing FAB by a cognitive intervention and exposure to activities regarded as fearful was as effective as lumbar fusion for reduction of pain and disability in patients with chronic low back pain [16]. In addition, FAB and muscle strength was more improved at 1-year follow-up after nonoperative treatment [17–19]. The difference in FAB and was maintained at 4-year follow-up [20,21]. No difference in any outcome was found at 9-year follow-up [21,22]. Results suggest that FAB may be reduced among patients with chronic low back pain. In another trial, multidisiplinary rehabilitation did not reduce FAB as compared with lumbar disc prosthesis [23]. Lack of success in reducing FAB in the nonoperative group may have contributed to less improvement in pain and disability. The authors of the present systematic review conclude that the treatment strategy should be modified when FAB is present. The key question arising is how the current treatment strategy best could be modified. What is most effective: to challenge the patients’ thoughts by a cognitive intervention; to expose the patients to nonrecommended activities such as bending, lifting, and jumping; or combining the two in cognitive behavioral treatments? Is it advisable in agreement with Cover Jones [7] to combine safe and pleasant activities with fearful movements to decondition kinesiophobia and avidance? How comprehensive should the intervention be? How many sessions? Who should perform the interventions: general practitioners; specialists in physical medicine and rehabilitation; psychologists; physiotherapists; or multidisiplinary? In a trial including patients sick-listed for about 12 weeks (in the present systematic review) we compared three common interventions: treatment as usual, a brief cognitive intervention by a specialist in physical medicine and a physiotherapist (1–2 consultations), and a fitness program including about 20 sessions [24]. The trial was relatively small and no difference was found for the main outcome, return to work. Both the fitness program and the brief cognitive intervention reduced FAB compared with usual care (not correctly reported in the present systematic review). Another trial reported that both exposure and graded activity reduced the FABs [25].
The educational aspect The FAM may have focused too much on the psychological aspect of fear (like negative affect, catastrophizing), whereas other educational aspects may be equally important. Previous studies have reported that specialists dealing with low back pain have high FAB [26,27]. These health-care providers are likely to recommend their patients to restrict physical activity that may negatively influence outcome [26–28]. From this perspective, modifying treatment
J.I. Brox / The Spine Journal 14 (2014) 2679–2681
strategies should start with better education or re-education of health-care providers [29]. Clinicians may enhance their ability to assess the unpleasant situation of their low back pain patients by achieving a better understanding of FAB. There is a potential value of information that may lessen fear and concerns about pain and activities. The effectiveness of an educational program was assessed in a current trial [30]. Short (6 hours) biomedical and biopsychosocial educational courses for physiotherapy students were given. Fear avoidance belief and recommendations for work and physical activity were assessed before and after the intervention. It was found that the biopsychosocial course reduced students’ FAB compared with the biomedical course. Similar differences were found for recommendations to stay at work and to stay active. The study did not evaluate how the modified beliefs and attitudes were maintained over time and how it influenced the students’ future clinical practice. It is difficult to understand why the authors of the present review recommend to evaluate subgroup analyses of patients with normal FAB in future studies. An improvement is not expected and subgroup analyses generally provide poor evidence of causal relationships.
References [1] Wertli MM, Eugster R, Held U, Steurer J, Kofmehl R, Weiser S. Catastrophizing—a prognostic factor for outcome in patients with low back pain: a systematic review. Spine J 2014;14:2639–57. [2] Wertli MM, Rasmussen-Barr E, Held U, Weiser S, Bachmann LM, Brunner F. Fear-avoidance beliefs—a moderator of treatment efficacy in patients with low back pain: a systematic review. Spine J 2014;14: 2658–78. [3] Wideman TH, Asmundson GG, Smeets RJ, Zautra AJ, Simmonds MJ, Sullivan MJ, et al. Rethinking the fear avoidance model: toward a multidimensional framework of pain-related disability. Pain 2013;154:2262–5. [4] Vlaeyen JW, Groenman NH, Thomassen J, Schuerman JA, van Eek H, Snijders AM, et al. A behavioral treatment for sitting and standing intolerance in a patient with chronic low back pain. Clin J Pain 1989;5:233–7. [5] Vlaeyen JW, Kole-Snijders AM, Boeren RG, van Eek H. Fear of movement/(re)injury in chronic low back pain and its relation to behavioral performance. Pain 1995;62:363–72. [6] Watson JB, Rayner R. Conditional emotional reactions. J Psychol 1920;3:1–14. [7] Cover Jones M. A laboratory study of fear: the case of Peter. Pedagog Semin J Genet Psychol 1924;31:308–15. [8] Hancock MJ, Maher CG, Latimer J, McLachlan AJ, Cooper CW, Day RO, et al. Assessment of diclofenac or spinal manipulative therapy, or both, in addition to recommended first-line treatment for acute low back pain: a randomised controlled trial. Lancet 2007;370:1638–43. [9] Lethem J, Slade PD, Troup JD, Bentley G. Outline of a fearavoidance model of exaggerated pain perception-I. Behav Res Ther 1983;21:401–8. [10] Waddell G. 1987 Volvo award in clinical sciences. A new clinical model for the treatment of low-back pain. Spine 1987;12:632–44. [11] Waddell G, Newton M, Henderson I, Somerville D, Main CJ. A fearavoidance beliefs questionnaire (FABQ) and the role of fear-avoidance beliefs in chronic low back pain and disability. Pain 1993;52:157–68. [12] Sullivan MJL, Bishop SR, Pivik J. The pain catastrophizind scale: development and validation. Psychol Assess 1995;7:524–32.
2681
[13] Rosenstiel AK, Keefe FJ. The use of coping strategies in chronic low back pain patients: relationship to patient characteristics and current adjustment. Pain 1983;17:33–44. [14] Flor H, Behle DJ, Birbaumer N. Assessment of pain-related cognitions in chronic pain patients. Behav Res Ther 1993;31:63–73. [15] Myhre K, Røe C, Marchand GH, Keller A, Bautz-Holter E, Leivseth G, et al. Fear-avoidance beliefs associated with perceived psychological and social factors at work among patients with neck and back pain: a cross-sectional multicentre study. BMC Musculoskelet Disord 2013;14:329. [16] Brox JI, Storheim K, Grotle M, Tveito TH, Indahl A, Eriksen HR. Systematic review of back schools, brief education, and fearavoidance training for chronic low back pain. Spine J 2008;8:948–58. [17] Brox JI, Sørensen R, Friis A, Nygaard Ø, Indahl A, Keller A, et al. Randomized clinical trial of lumbar instrumented fusion and cognitive intervention and exercises in patients with chronic low back pain and disc degeneration. Spine 2003;28:1913–21. [18] Brox JI, Reiker as O, Nygaard Ø, Sørensen R, Indahl A, Holm I, et al. Lumbar instrumented fusion compared with cognitive intervention and exercises in patients with chronic back pain after previous surgery for disc herniation: a prospective randomized controlled study. Pain 2006;122:145–55. [19] Keller A, Brox JI, Gunderson R, Holm I, Friis A, Reiker as O. Trunk muscle strength, cross-sectional area, and density in patients with chronic low back pain randomized to lumbar fusion or cognitive intervention and exercises. Spine 2004;29:3–8. [20] Brox JI, Nygaard ØP, Holm I, Keller A, Ingebrigtsen T, Reiker as O. Four-year follow-up of surgical versus non-surgical therapy for chronic low back pain. Ann Rheum Dis 2010;69:1643–8. [21] Froholdt A, Reikeraas O, Holm I, Keller A, Brox JI. No difference in 9year outcome in CLBP patients randomized to lumbar fusion versus cognitive intervention and exercises. Eur Spine J 2012;21:2531–8. [22] Froholdt A, Holm I, Keller A, Gunderson RB, Reikeraas O, Brox JI. No difference in long-term trunk muscle strength, cross-sectional area, and density in patients with chronic low back pain 7 to 11 years after lumbar fusion versus cognitive intervention and exercises. Spine J 2011;11:718–25. [23] Hellum C, Johnsen LG, Storheim K, Nygaard OP, Brox JI, Rossvoll I, et al, Norwegian Spine Study Group. Surgery with disc prosthesis versus rehabilitation in patients with low back pain and degenerative disc: two year follow-up of randomised study. BMJ 2011;342:d2786. [24] Storheim K, Brox JI, Holm I, Koller AK, Bø K. Intensive group training versus cognitive intervention in sub-acute low back pain: short-term results of a single-blind randomized controlled trial. J Rehabil Med 2003;35:132–40. [25] Leeuw M, Goossens ME, van Breukelen GJ, de Jong JR, Heuts PH, Smeets RJ, et al. Exposure in vivo versus operant graded activity in chronic low back pain patients: esults of a randomized controlled trial. Pain 2008;138:192–207. [26] Rainville J, Bagnall D, Phalen L. Health care providers’ attitudes and beliefs about functional impairments and chronic back pain. Clin J Pain 1995;11:287–95. [27] Rainville J, Carlson N, Polatin P, Gatchel RJ, Indahl A. Exploration of physicians’ recommendations for activities in chronic low back pain. Spine 2000;25:2210–20. [28] Buchbinder R, Staples M, Jolley D. Doctors with a special interest in back pain have poorer knowledge about how to treat back pain. Spine 2009;34:1218–26. [29] Rainville J, Smeets RJ, Bendix T, Tveito TH, Poiraudeau S, Indahl AJ. Fear-avoidance beliefs and pain avoidance in low back pain: translating research into clinical practice. Spine J 2011;11: 895–903. [30] Domenech J, Sanchez-Zuriaga D, Segura-Ortı E, Espejo-Tort B, Lison JF. Impact of biomedical and biopsychosocial training sessions on the attitudes, beliefs, and recommendations of health care providers about low back pain: a randomised clinical trial. Pain 2011;152:2557–63.
Commentary
Current evidence on catastrophizing and fear avoidance beliefs in low back pain patients Jens Ivar Brox, MD, PhD* Department of Physical Medicine and Rehabilitation, Oslo University Hospital, University of Oslo, Pb 4950 Nydalen, N-0424 Oslo, Norway Received 1 August 2014; accepted 23 August 2014
COMMENTARY ON: Wertli MM, Rasmussen-Barr E, Held U, Weiser S, Bachmann LM, Brunner F. Fear-avoidance beliefs—a moderator of treatment efficacy in patients with low back pain: a systematic review. Spine J 2014;14:2658–78 (in this issue).
Two systematic reviews published in the present edition of the Spine Journal support that the fear avoidance model (FAM) is important for understanding the prognosis in patients with low back pain [1,2]. This is in contrast to the critics of the FAM in a recent topical review published in Pain [3]. The authors of the latter review suggested replacing the FAM by a multidimensional framework of pain-related disability. Although topical reviews may provide theories and new hypotheses, the aim of systematic reviews is to summarize the best evidence available from empirical studies. Possible disadvantages are that important details may be overlooked and that studies may either not be identified or not analyzed because of narrow inclusion criteria. Particularly for psychological variables, the transformation of beliefs, attitudes, and symptoms into numerical scores analyzed as linear variables is a scientific challenge. Therefore, the results from systematic reviews extracting information from studies using standardized questionnaires should be supplemented by studies using different research methodologies, such as interviews and observation. The initial studies from Vlaeyen et al. [4,5] proposing the FAM used qualitative methods. Findings contributed to a paradigm shift opposing the more common biomedical model for treatment of low back pain.
Little Albert Fear as a phobic stimulus may be traced back to the classic study published in 1920 by the psychologists John B. FDA device/drug status: Not applicable. Author disclosures: JIB: Nothing to disclose. * Corresponding author. Department of Physical Medicine and Rehabilitation, Oslo University Hospital, University of Oslo, Oslo, Norway. Tel.: þ4797702383. E-mail address: [email protected] (J.I. Brox) http://dx.doi.org/10.1016/j.spinee.2014.08.454 1529-9430/Ó 2014 Elsevier Inc. All rights reserved.
Watson and Rosaline Rayner at John Hopkins University [6]. In their experiment with little Albert, aged 9 months, a normally pleasant stimulus was conditioned or learned to be fearful. This study that would have been considered unethical today, provided evidence of classical conditioning in humans. At baseline, the emotionally stable child showed no fear of the white rat, but by introducing a loud sound little Albert started to cry and show fear, which after pairing of the two stimuli turned into distress and avoidance behavior as just the white rat appeared in the room. This experiment has been criticized not just for ethical reasons, but also because there was no control subject and no post experiment in an attempt to reduce fear. A study by Cover Jones [7] published some years later suggests that it is possible to reduce fear and avoidance while repeatedly introducing a pleasant stimulus together with the fearful stimulus. Is it possible to translate this experiment into the FAM? A patient experiencing acute back pain that is aggravated by movement will try to avoid this unless he or she is convinced that it is safe to move. Acute back pain has a favorable prognosis and pain will recover in most patients independent of treatment [8]. The question is why fear and avoidance do not always fade away and in some patients become chronic. Have health-care providers become the conditioning stimulus by restricting the patient’s physical activity? The FAM was proposed in 1983 by Lethem et al. [9]. Later Waddell et al. [10,11] introduced the biopsychosocial model to better understand the failures of strict biomedical informed treatment. In 1993, they published a questionnaire for measuring fear avoidance beliefs (FABs) [11]. The central concept of the FAM is fear of pain. It is debated whether this has to be preceded by catastrophizing. It may be argued that a patient is unlikely to demonstrate fear of pain unless some kind of illness information together with negative affectivity is processed. Sensory, biomedical,
2680
J.I. Brox / The Spine Journal 14 (2014) 2679–2681
emotional, cognitive, and behavioral aspects of pain are associated with physical performance and self-reported disability. It is debated whether the critical factor is pain or the consequences of pain. The FAM proposes confrontation and avoidance as the two extreme responses to pain, of which the former leads to reduction of fear over time. Avoidance leads to exacerbation and maintenance of fear that may generate a phobic state. The purpose of the first systematic review was to examine the importance of catastrophizing as a coping strategy in patients with low back pain [1]. High catastrophizers experienced worse outcome In the present systematic review, 89% of the records screened for inclusion were excluded. This suggests that results are prone to selection bias, but the authors have described the prespecified inclusion criteria in detail and exclusions seem justified. Twelve of the 16 included studies evaluated self-reported outcomes. Most of them found that catastrophizing was associated with pain and disability at follow-up. Five of six studies that applied cutoff values for the total score found that patients identified as high catastrophizers experienced worse outcome compared with low catastrophizers. The pain catastrophizing scale [12], the coping strategies questionnaire [13], and the pain-related questionnaire [14] were used to measure catastrophizing. These scales are only partly validated and the moderate correlation between two of the scales suggests that they are not measuring the same construct. One additional limitation was that the variability of patient scores was low. The discussion highlights the gaps in the literature and makes appropriate recommendations for future research. The article is easy to read and additional information is provided in the appendix. High FAB scores are associated with worse outcome The second systematic review evaluated the influence of FABs on work-related outcome, pain, and disability. Inclusion was limited to randomized controlled trials that investigated nonoperative treatment efficacy. Of 646 records, 78 studies were carefully evaluated, 12 high-quality studies and 5 lowquality studies were included. The authors concluded that in patients with low back pain for less than 6 months there was high-quality evidence that FAB (high scores) was associated with more pain and disability and less return to work. A decrease in FAB was associated with better outcome (moderate-quality evidence). Interventions that addressed FAB were most effective (moderate-quality evidence). In patients with chronic pain findings were less consistent. Perceived psychological and social factors at work were strongly associated with FABs about work in sick-listed back and neck patients [15]. Possible methodological aspects that should be further evaluated in future studies are that the outcome measures applied (FABQ [FAB questionnaire] and Tampa Kinesiophobia Scale) are only
moderately correlated and that cutoff values for high and low scores are debated. In a previous systematic review, we reported that a nonoperative intervention addressing FAB by a cognitive intervention and exposure to activities regarded as fearful was as effective as lumbar fusion for reduction of pain and disability in patients with chronic low back pain [16]. In addition, FAB and muscle strength was more improved at 1-year follow-up after nonoperative treatment [17–19]. The difference in FAB and was maintained at 4-year follow-up [20,21]. No difference in any outcome was found at 9-year follow-up [21,22]. Results suggest that FAB may be reduced among patients with chronic low back pain. In another trial, multidisiplinary rehabilitation did not reduce FAB as compared with lumbar disc prosthesis [23]. Lack of success in reducing FAB in the nonoperative group may have contributed to less improvement in pain and disability. The authors of the present systematic review conclude that the treatment strategy should be modified when FAB is present. The key question arising is how the current treatment strategy best could be modified. What is most effective: to challenge the patients’ thoughts by a cognitive intervention; to expose the patients to nonrecommended activities such as bending, lifting, and jumping; or combining the two in cognitive behavioral treatments? Is it advisable in agreement with Cover Jones [7] to combine safe and pleasant activities with fearful movements to decondition kinesiophobia and avidance? How comprehensive should the intervention be? How many sessions? Who should perform the interventions: general practitioners; specialists in physical medicine and rehabilitation; psychologists; physiotherapists; or multidisiplinary? In a trial including patients sick-listed for about 12 weeks (in the present systematic review) we compared three common interventions: treatment as usual, a brief cognitive intervention by a specialist in physical medicine and a physiotherapist (1–2 consultations), and a fitness program including about 20 sessions [24]. The trial was relatively small and no difference was found for the main outcome, return to work. Both the fitness program and the brief cognitive intervention reduced FAB compared with usual care (not correctly reported in the present systematic review). Another trial reported that both exposure and graded activity reduced the FABs [25].
The educational aspect The FAM may have focused too much on the psychological aspect of fear (like negative affect, catastrophizing), whereas other educational aspects may be equally important. Previous studies have reported that specialists dealing with low back pain have high FAB [26,27]. These health-care providers are likely to recommend their patients to restrict physical activity that may negatively influence outcome [26–28]. From this perspective, modifying treatment
J.I. Brox / The Spine Journal 14 (2014) 2679–2681
strategies should start with better education or re-education of health-care providers [29]. Clinicians may enhance their ability to assess the unpleasant situation of their low back pain patients by achieving a better understanding of FAB. There is a potential value of information that may lessen fear and concerns about pain and activities. The effectiveness of an educational program was assessed in a current trial [30]. Short (6 hours) biomedical and biopsychosocial educational courses for physiotherapy students were given. Fear avoidance belief and recommendations for work and physical activity were assessed before and after the intervention. It was found that the biopsychosocial course reduced students’ FAB compared with the biomedical course. Similar differences were found for recommendations to stay at work and to stay active. The study did not evaluate how the modified beliefs and attitudes were maintained over time and how it influenced the students’ future clinical practice. It is difficult to understand why the authors of the present review recommend to evaluate subgroup analyses of patients with normal FAB in future studies. An improvement is not expected and subgroup analyses generally provide poor evidence of causal relationships.
References [1] Wertli MM, Eugster R, Held U, Steurer J, Kofmehl R, Weiser S. Catastrophizing—a prognostic factor for outcome in patients with low back pain: a systematic review. Spine J 2014;14:2639–57. [2] Wertli MM, Rasmussen-Barr E, Held U, Weiser S, Bachmann LM, Brunner F. Fear-avoidance beliefs—a moderator of treatment efficacy in patients with low back pain: a systematic review. Spine J 2014;14: 2658–78. [3] Wideman TH, Asmundson GG, Smeets RJ, Zautra AJ, Simmonds MJ, Sullivan MJ, et al. Rethinking the fear avoidance model: toward a multidimensional framework of pain-related disability. Pain 2013;154:2262–5. [4] Vlaeyen JW, Groenman NH, Thomassen J, Schuerman JA, van Eek H, Snijders AM, et al. A behavioral treatment for sitting and standing intolerance in a patient with chronic low back pain. Clin J Pain 1989;5:233–7. [5] Vlaeyen JW, Kole-Snijders AM, Boeren RG, van Eek H. Fear of movement/(re)injury in chronic low back pain and its relation to behavioral performance. Pain 1995;62:363–72. [6] Watson JB, Rayner R. Conditional emotional reactions. J Psychol 1920;3:1–14. [7] Cover Jones M. A laboratory study of fear: the case of Peter. Pedagog Semin J Genet Psychol 1924;31:308–15. [8] Hancock MJ, Maher CG, Latimer J, McLachlan AJ, Cooper CW, Day RO, et al. Assessment of diclofenac or spinal manipulative therapy, or both, in addition to recommended first-line treatment for acute low back pain: a randomised controlled trial. Lancet 2007;370:1638–43. [9] Lethem J, Slade PD, Troup JD, Bentley G. Outline of a fearavoidance model of exaggerated pain perception-I. Behav Res Ther 1983;21:401–8. [10] Waddell G. 1987 Volvo award in clinical sciences. A new clinical model for the treatment of low-back pain. Spine 1987;12:632–44. [11] Waddell G, Newton M, Henderson I, Somerville D, Main CJ. A fearavoidance beliefs questionnaire (FABQ) and the role of fear-avoidance beliefs in chronic low back pain and disability. Pain 1993;52:157–68. [12] Sullivan MJL, Bishop SR, Pivik J. The pain catastrophizind scale: development and validation. Psychol Assess 1995;7:524–32.
2681
[13] Rosenstiel AK, Keefe FJ. The use of coping strategies in chronic low back pain patients: relationship to patient characteristics and current adjustment. Pain 1983;17:33–44. [14] Flor H, Behle DJ, Birbaumer N. Assessment of pain-related cognitions in chronic pain patients. Behav Res Ther 1993;31:63–73. [15] Myhre K, Røe C, Marchand GH, Keller A, Bautz-Holter E, Leivseth G, et al. Fear-avoidance beliefs associated with perceived psychological and social factors at work among patients with neck and back pain: a cross-sectional multicentre study. BMC Musculoskelet Disord 2013;14:329. [16] Brox JI, Storheim K, Grotle M, Tveito TH, Indahl A, Eriksen HR. Systematic review of back schools, brief education, and fearavoidance training for chronic low back pain. Spine J 2008;8:948–58. [17] Brox JI, Sørensen R, Friis A, Nygaard Ø, Indahl A, Keller A, et al. Randomized clinical trial of lumbar instrumented fusion and cognitive intervention and exercises in patients with chronic low back pain and disc degeneration. Spine 2003;28:1913–21. [18] Brox JI, Reiker as O, Nygaard Ø, Sørensen R, Indahl A, Holm I, et al. Lumbar instrumented fusion compared with cognitive intervention and exercises in patients with chronic back pain after previous surgery for disc herniation: a prospective randomized controlled study. Pain 2006;122:145–55. [19] Keller A, Brox JI, Gunderson R, Holm I, Friis A, Reiker as O. Trunk muscle strength, cross-sectional area, and density in patients with chronic low back pain randomized to lumbar fusion or cognitive intervention and exercises. Spine 2004;29:3–8. [20] Brox JI, Nygaard ØP, Holm I, Keller A, Ingebrigtsen T, Reiker as O. Four-year follow-up of surgical versus non-surgical therapy for chronic low back pain. Ann Rheum Dis 2010;69:1643–8. [21] Froholdt A, Reikeraas O, Holm I, Keller A, Brox JI. No difference in 9year outcome in CLBP patients randomized to lumbar fusion versus cognitive intervention and exercises. Eur Spine J 2012;21:2531–8. [22] Froholdt A, Holm I, Keller A, Gunderson RB, Reikeraas O, Brox JI. No difference in long-term trunk muscle strength, cross-sectional area, and density in patients with chronic low back pain 7 to 11 years after lumbar fusion versus cognitive intervention and exercises. Spine J 2011;11:718–25. [23] Hellum C, Johnsen LG, Storheim K, Nygaard OP, Brox JI, Rossvoll I, et al, Norwegian Spine Study Group. Surgery with disc prosthesis versus rehabilitation in patients with low back pain and degenerative disc: two year follow-up of randomised study. BMJ 2011;342:d2786. [24] Storheim K, Brox JI, Holm I, Koller AK, Bø K. Intensive group training versus cognitive intervention in sub-acute low back pain: short-term results of a single-blind randomized controlled trial. J Rehabil Med 2003;35:132–40. [25] Leeuw M, Goossens ME, van Breukelen GJ, de Jong JR, Heuts PH, Smeets RJ, et al. Exposure in vivo versus operant graded activity in chronic low back pain patients: esults of a randomized controlled trial. Pain 2008;138:192–207. [26] Rainville J, Bagnall D, Phalen L. Health care providers’ attitudes and beliefs about functional impairments and chronic back pain. Clin J Pain 1995;11:287–95. [27] Rainville J, Carlson N, Polatin P, Gatchel RJ, Indahl A. Exploration of physicians’ recommendations for activities in chronic low back pain. Spine 2000;25:2210–20. [28] Buchbinder R, Staples M, Jolley D. Doctors with a special interest in back pain have poorer knowledge about how to treat back pain. Spine 2009;34:1218–26. [29] Rainville J, Smeets RJ, Bendix T, Tveito TH, Poiraudeau S, Indahl AJ. Fear-avoidance beliefs and pain avoidance in low back pain: translating research into clinical practice. Spine J 2011;11: 895–903. [30] Domenech J, Sanchez-Zuriaga D, Segura-Ortı E, Espejo-Tort B, Lison JF. Impact of biomedical and biopsychosocial training sessions on the attitudes, beliefs, and recommendations of health care providers about low back pain: a randomised clinical trial. Pain 2011;152:2557–63.
