Johannes Vlaeyen

Disuse and deconditioning in chronic low back pain: Concepts and hypotheses on contributing mechanisms

For years enhancement of a patients level of physical fitness has been an important goal in rehabilitation treatment in chronic low back pain (CLBP), based on the hypothesis that physical deconditioning contributes to the chronicity of low back pain. However, whether this hypothesis in CLBP holds is not clear. In this paper, possible mechanisms that contribute to the development of physical deconditioning in CLBP, such as avoidance behaviour and suppressive behaviour, are discussed. The presence of both deconditioning‐related physiological changes, such as muscle atrophy, changes in metabolism, osteoporosis and obesity as well as deconditioning related functional changes, such as a decrease in cardiovascular capacity, a decrease in muscle strength and impaired motor control in patients with CLBP are discussed. Results of studies on the level of physical activities in daily life (PAL) and the level of physical fitness in patients with CLBP compared to healthy controls were reviewed. In studies on PAL results that were either lower or comparable to healthy subjects were found. The presence of disuse (i.e., a decrease in the level of physical activities in daily life) in patients with CLBP was not confirmed. The inconclusive findings in the papers reviewed may partly be explained by different measurement methods used in research on PAL in chronic pain. The level of physical fitness of CLBP patients also appeared to be lower or comparable to the fitness level of healthy persons. A discriminating factor between fit and unfit patients with back pain may be the fact that fit persons more frequently are still employed, and as such may be involved more in physical activity. Lastly some suggestions are made for further research in the field of disuse and deconditioning in CLBP.

Quality of life in chronic pain is more associated with beliefs about pain, than with pain intensity

Objectives. The objectives of this study were to investigate pain cognitions and quality of life of chronic pain patients referred to a multi‐disciplinary university pain management clinic and to search for predictors of quality of life.

Disuse and physical deconditioning in the first year after the onset of back pain

Abstract For years, physical deconditioning has been thought to be both a cause and a result of back pain. As a consequence physical reconditioning has been proposed as treatment‐goal in patients with chronic low back pain (LBP). However, it is still unclear whether a patient’s physical fitness level really decreases after pain‐onset. The objectives of the present study were, firstly, to test the assumption that long‐term non‐specific LBP leads to a decrease of the level of physical activity (disuse), secondly, to evaluate any development of physical deconditioning as a result of disuse in CLBP, and thirdly, to evaluate predictors for disuse in CLBP. A longitudinal cohort study over one year including 124 patients with sub‐acute LBP (i.e., 4–7 weeks after pain onset) was performed. Main outcome measures were change in physical activity level (PAL) and physical fitness (measured by changes in body weight, body fat and muscle strength) over one year. Hypothesized predictors for disuse were: pain catastrophizing; fear of movement; depression; physical activity decline; the perceived level of disability and PAL prior to pain. Results showed that only in a subgroup of patients a PAL‐decrease had occurred after the onset of pain, whereas no signs of physical deconditioning were found. Negative affect and the patients’ perceived physical activity decline in the subacute phase predicted a decreased level of PAL over one year. Based on these results, we conclude that as to the assumption that patients with CLBP suffer from disuse and physical deconditioning empirical evidence is still lacking.

Fear of injury and physical deconditioning in patients with chronic low back pain

OBJECTIVES To test the assumption that fear of injury leads to disability and physical deconditioning in patients with chronic low back pain (CLBP) and to evaluate the relation between disability and physical deconditioning. DESIGN Survey in a cross-sectional design. SETTING A rehabilitation center in the Netherlands. PARTICIPANTS Forty patients with nonspecific CLBP. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Fear of injury was measured with the Tampa Scale of Kinesiophobia. Physical fitness was expressed in aerobic fitness measured as predicted maximum oxygen consumption derived in a submaximal exercise test according the protocol of Siconolfi. Disability was measured with the Roland Disability Questionnaire. The association between fear of injury and physical fitness or disability was examined with correlational and multiple linear regression analyses. RESULTS Fear of injury correlated significantly with disability (r=.44), but did not correlate significantly with aerobic fitness. There was no statistically significant association between disability and aerobic fitness. Multiple regression analysis revealed that aerobic fitness was predicted by gender only. CONCLUSIONS Fear of injury appears to be more strongly associated with perceived disability than with aerobic fitness. The assumption that fear of injury leads to physical deconditioning was not confirmed in this sample of patients with CLBP.

Pain-related fear in low back pain: A prospective study in the general population

A cognitive behavioural account of chronic low back pain (CLBP) proposes that the relationship between pain catastrophizing and functional disability is mediated by fear of movement/(re)injury. Several clinical studies already demonstrated the contribution of pain catastrophizing and fear of movement/(re)injury in the development and maintenance of CLBP. This study included people with low back pain (LBP) in the general population, and aimed to investigate whether fear of movement/(re)injury mediated the relationship between pain catastrophizing and functional disability, by examining several prerequisites for mediation. Data from the Dutch population‐based Musculoskeletal Complaints and Consequences Cohort (DMC3) study were used, including 152 people suffering from LBP who completed both a follow‐up questionnaire and a baseline questionnaire 6 months previously. This study was unable to demonstrate that the relationship between pain catastrophizing and functional disability was mediated by fear of movement/(re)injury, since the prerequisite that pain catastrophizing and functional disability were related, was not fulfilled. However, pain catastrophizing was significantly related to fear of movement/(re)injury 6 months later, above and beyond other contributing variables such as fear of movement/(re)injury already present at baseline. On its turn, fear of movement/(re)injury was related to functional disability, in addition to pain intensity. Although this study leaves some indistinctness concerning the actual relationships between pain catastrophizing, fear of movement/(re)injury, and functional disability, it does provide some evidence for the contributing role of these factors in LBP in the general population.

Do health care providers' attitudes towards back pain predict their treatment recommendations? Differential predictive validity of implicit and explicit attitude measures

&NA; The current study aimed to measure the differential predictive value of implicit and explicit attitude measures on treatment behaviour of health care providers. Thirty‐six physiotherapy students completed a measure of explicit treatment attitude (Pain Attitudes And Beliefs Scale For Physiotherapists—PABS‐PT) and a measure of implicit treatment attitude (Extrinsic Affective Simon Task—EAST). Furthermore, they gave treatment recommendations for a patient simulating back pain on three video scenes. The implicit and explicit measures of attitudes were only weakly related to each other. However, both were differentially related to treatment recommendations. The implications of the differential predictive value of implicit and explicit attitude measures for treatment behaviour are discussed.

Fear of movement/injury in the general population: Factor structure and psychometric properties of an adapted version of the Tampa Scale for Kinesiophobia

In recent years, several studies have pointed out the importance of pain-related fear in the development and maintenance of chronic pain. An important instrument for measuring pain-related fear in the context of low back pain is the Tampa Scale for Kinesiophobia (TSK). Recently, a version of this questionnaire has been developed for administration among the general population (TSK-G). To determine the factor structure of the TSK-G, data from a random sample of the Dutch general population were studied separately for people who had had back complaints in the previous year, and people who had been without back complaints. For both groups the TSK-G appeared to consist of one, internally consistent, factor of 12 items. The one-factor TSK-G also appeared valid after comparison with scores on measures of catastrophizing and general health status.

Dutch version of the pain vigilance and awareness questionnaire: Validity and reliability in a pain-free population

The current study examined validity and reliability of the Pain Vigilance and Awareness Questionnaire (PVAQ) in two samples of healthy college students. Exploratory and confirmatory factor analysis showed that a two-factor model of the PVAQ was most suitable in the present study. The first factor could be referred to as attention to pain whereas the second factor could be specified as attention to changes in pain. With regard to the convergent and divergent validity, the PVAQ was found to correlate highly with related constructs like catastrophising (PCS) and general body vigilance (BVQ). The correlation between PVAQ and pain-related fear (FPQ) was moderate, whereas correlations with unrelated constructs like trait anxiety (STAI-T) and fear of spiders (FSQ) were low. Furthermore, the PVAQ showed good internal consistency and fair test-retest reliability. Altogether, these findings suggest that the PVAQ is a valid and reliable measure of pain vigilance in healthy individuals. The results of this study can be regarded as a starting point for further validation of the PVAQ in clinical pain populations. Implications for future research and treatment interventions are discussed.

More is not always better: Cost-effectiveness analysis of combined, single behavioral and single physical rehabilitation programs for chronic low back pain

Several treatment principles for the reduction of chronic low back pain associated disability have been postulated. To examine whether a combination of a physical training and operant‐behavioral graded activity with problem solving training is cost‐effective compared to either alone one year post‐treatment, a full economic analysis alongside a randomized controlled trial was conducted. In total 172 patients with chronic disabling non‐specific low back pain referred for rehabilitation treatment, were randomized to 10 weeks of aerobic training and muscle strengthening of back extensors (active physical treatment; APT), 10 weeks of gradual assumption of patient relevant activities based on operant‐behavioral principles and problem solving training (graded activity plus problem solving training; GAP), or APT combined with GAP (combination treatment; CT). Total costs, existing of direct health and non‐health costs and indirect costs due to absence of paid work were calculated by using cost diaries and treatment attendance lists. The Roland Disability Questionnaire was used to calculate the cost‐effectiveness to reduce disability and the gain in quality adjusted life year (QALY) by using the EuroQol‐5D. APT, followed by CT showed, although not significant, higher total costs than GAP. Reduction of disability and gain in QALY did not differ significantly between CT and the single treatment modalities. Based on the incremental cost effectiveness ratios (ICERs) and cost‐effectiveness acceptability curves CT is not cost‐effective at all. However, GAP is cost‐effective regarding the reduction of disability and gain in QALY, and to a lesser degree APT is more cost‐effective than CT in reducing disability.

Applying the fear-avoidance model to the chronic whiplash syndrome

This article reviews the literature to ascertain whether the fear-avoidance model, which was developed to expain back pain, might also apply to whiplash. Although there are large gaps in the data, some evidence suggests that the model is useful and may guide future research.