Associations between psychological factors, pressure pain thresholds and conditioned pain modulation and disability in (sub)-acute low back pain: a three-month follow-up study.

BACKGROUND: The clinical presentation and pain experience of patients with (sub)-acute low back pain ((S)ALBP) can strongly vary in clinical practice. However, despite growing evidence that psychological factors are associated with disability in chronic pain conditions including low back pain, studies examining the influence of psychological factors, quantitative sensory testing (QST) (i.e. pressure pain thresholds (PPTs)) and conditioned pain modulation (CPM) on future disability are still lacking in (S)ALBP. OBJECTIVE: This prospective cohort study aims to determine associations between baseline psychological factors, PPTs and CPM in (S)ALBP and disability after 3 months. METHODS: Fifty-two patients with (S)ALBP underwent a baseline PPT evaluation in rest and during a CPM protocol. Patients were asked to fill in self-report questionnaires: the Visual Analogue Scale (VAS), the Quebec Back Pain Disability Scale (QBPDS), the Pain Catastrophizing Scale (PCS), the Tampa Scale for Kinesiophobia (TSK) and the Illness Perception Questionnaire - Brief version (IPQ-B). At 3-month follow-up, participants were asked to fill in the QBPDS again. Multiple linear regression analysis was conducted to determine associations between baseline factors and disability at follow-up. RESULTS: Thirty-eight patients participated at follow-up. Because of the multicollinearity issue, the TSK score was selected for analyses and the PCS and IPQ-B score were excluded from the model. No significant associations between baseline factors and disability at follow-up were found. CONCLUSION: Neither baseline psychological factors nor PPTs or CPM in (S)ALBP were significantly associated with disability after 3 months. Our multiple linear regression analysis was likely underpowered to detect significant associations.

Evidence for alterations to dynamic quantitative sensory tests in patients with chronic temporomandibular myalgia: A systematic review of observational studies with meta-analysis.

BACKGROUND: Conflicting results exist between somatosensory profiles of patients with temporomandibular myalgia (TMDm). The objective of this review was to examine whether adults with TMDm show altered responses to dynamic quantitative sensory tests compared with healthy controls. METHODS: We searched five electronic databases for studies, excluding those without suitable controls or where TMDm was associated with confounding non-musculoskeletal disorders. Risk of bias was assessed with the SIGN case-control study checklist. Findings were structured around dynamic quantitative sensory tests and their localization. Where possible, we performed meta-analysis with a random inverse variance model to compare patients with TMDm and healthy controls. Statistical heterogeneity was estimated with Chi² test and inconsistency index, I². RESULTS: We extracted data from 23 studies comprising 1284 adults with chronic TMDm and 2791 healthy controls. Risk of bias was assessed as high for 20 studies. Mechanical temporal summation, the most studied phenomenon (14 studies), is increased in the upper limb of patients with TMDm (SMD = 0.43; 95% CI: .11 to .75; p = .009) but not in the jaw area (p = .09) or in the cervical area (p = .29). Very little evidence for altered thermal temporal summation (five studies), conditioned pain modulation (seven studies), exercise-induced hypoalgesia (two studies), placebo analgesia (two studies), stress-induced hypoalgesia (one study) and offset analgesia (one study) was found. DISCUSSION: A major limitation of this review was the risk of bias of included studies. Future studies would benefit from following methodological guidelines and consideration of confounding factors.

Energy spectral density as valid parameter to compare postural control between subjects with nonspecific chronic low back pain vs healthy subjects: A case-control study.

BACKGROUND: Nonspecific chronic low back pain (NSCLBP) is one of the most common and frequent health problems. OBJETIVE: to compare postural control (i.e. center of pressure (CoP) displacement and energy spectral density (ESD)) using technological devices (accelerometers and pressure platform) between subjects with NSCLBP and healthy subjects. METHODS: A cross-sectional case-control study was conducted. Observational study (STROBE). The final sample consisted of 60 subjects (30 NSCLBP subjects and 30 healthy subjects). Triaxial accelerometer and pressure platform were used in order to obtain ESD and CoP displacement measurements during four balance tasks (i.e. with and without vision and on stable versus unstable surface). Independent t tests were used to compare participants with NSCLBP and healthy controls in the two clinical measurements (i.e., CoP displacement and ESD) for the four balance tests. A multivariate analysis of variance (MANOVA) together with a Fisher's linear discrimination was applied in order to categorize NSPLBP. RESULTS: Patients with NSCLBP showed greater CoP migration in the positions eyes open, stable surface on the anteroposterior axis (p = 0.012), eyes closed, stable surface on the mediolateral axis (p = 0.025), eyes closed, stable surface on the anteroposterior axis (p = 0.001), eyes open, unstable surface on the anteroposterior axis (p = 0.040), eyes closed, unstable surface on the anteroposterior axis (p = 0.015). Also the ESD was significantly greater for the four situations described (p ≤ 0.01) in subjects with NSCLBP. CONCLUSIONS: Accelerometer appears to be a technological device that could offer a potential benefit within the battery of tests on physical performance among subjects with NSCLBP and healthy subjects.

Illness Perceptions Explain the Variance in Functional Disability, but Not Habitual Physical Activity, in Patients With Chronic Low Back Pain: A Cross-Sectional Study.

INTRODUCTION: Although the importance of psychosocial factors has been highlighted in many studies in patients with chronic low back pain (CLBP), there is a lack of research examining the role of illness perceptions in explaining functional disability and physical activity in patients with CLBP. AIM: The aim of the study was to explore the value of illness perceptions in explaining functional disability and physical activity in patients with CLBP. METHODS: Eighty-four participants with CLBP (of > 3 months' duration) completed a battery of questionnaires investigating psychosocial factors (Pain Catastrophizing Scale [PCS], Illness Perceptions Questionnaire Revised [IPQ-R], and 36-Item Short Form mental health scale [SF-36_MH]) and perceived pain intensity (visual analog scale [VAS]), as well as the Oswestry Disability Index (ODI) and Baecke questionnaire. The latter 2 were entered separately as dependent variables in a regression analysis. RESULTS: The combined variables (VAS, PCS, SF-36_MH, IPQ-R) accounted for 62% of the variance in functional disability (ODI). Adding the results of the IPQ-R to the scores of the other 3 variables (VAS, PCS, SF-36_MH) significantly increased the explained variance of ODI scores in CLBP patients, yielding 18% additional information (P < 0.01). Only 5% of the variance in the Baecke questionnaire was explained by combining the 4 variables. None of the single variables alone made a significant contribution to R². CONCLUSIONS: Illness perceptions are an important factor for explaining functional disability, but not for explaining habitual physical activity in CLBP patients.

Unravelling Motor Learning Processes in Theater Performers.

Theater performers, more than common actors, experience high physical loadings. This study aimed at analyzing the motor behavior of novice performers (dancers/actors who were introduced to the acting method of Jan Fabre) by investigating the kinematics of a physical acting exercise in a prospective study. Two measurement sessions were organized: before and after the novice performers (N = 13) took part in seven workshops. Total body kinematics were registered using a three-dimensional motion capture system. Using a principal component analysis, six factors were disseminated out of 30 kinematic parameters: Pelvic Motion, Speed of Progression, Lower Limb Position, Foot Motion, Lower Limb Motion, and Trunk Posture. Although no main effect of training was found for any of the factors (.429 < p < .964), Trunk Posture showed a higher consistency after the workshops. This study succeeded in providing insights in the motor behavior of theater performers and revealed recognizable features of motor learning.

Pain Neurophysiology Education and Therapeutic Exercise for Patients With Chronic Low Back Pain: A Single-Blind Randomized Controlled Trial.

OBJECTIVE: To assess the effect of a pain neurophysiology education (PNE) program plus therapeutic exercise (TE) for patients with chronic low back pain (CLBP). DESIGN: Single-blind randomized controlled trial. SETTING: Private clinic and university. PARTICIPANTS: Patients with CLBP for ≥6 months (N=56). INTERVENTIONS: Participants were randomized to receive either a TE program consisting of motor control, stretching, and aerobic exercises (n=28) or the same TE program in addition to a PNE program (n=28), conducted in two 30- to 50-minute sessions in groups of 4 to 6 participants. MAIN OUTCOMES MEASURES: The primary outcome was pain intensity rated on the numerical pain rating scale which was completed immediately after treatment and at 1- and 3-month follow-up. Secondary outcome measures were pressure pain threshold, finger-to-floor distance, Roland-Morris Disability Questionnaire, Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, and Patient Global Impression of Change. RESULTS: At 3-month follow-up, a large change in pain intensity (numerical pain rating scale: -2.2; -2.93 to -1.28; P<.001; d=1.37) was observed for the PNE plus TE group, and a moderate effect size was observed for the secondary outcome measures. CONCLUSIONS: Combining PNE with TE resulted in significantly better results for participants with CLBP, with a large effect size, compared with TE alone.

History taking by physiotherapists with low back pain patients: are illness perceptions addressed properly?

PURPOSE: Despite the increasing evidence that illness perceptions should be addressed in patients, there is a lack of studies evaluating whether physiotherapists question illness perceptions. This study, using a mixed-methods design, investigates the integration of illness perceptions during the first consultation of physiotherapists treating patients with low back pain (LBP). METHODS: Thirty-four physiotherapists performed usual history taking in a patient with non-specific LBP. The interview was audiotaped and illness perceptions were indexed using an observational instrument, based on the domains of Leventhal's Common Sense Model. Patients were also asked to fill in the Illness Perception Questionnaire-Revised for LBP. RESULTS: Physiotherapists assessed the illness identity, also perceptions regarding the (physical) cause and controllability of LBP were evaluated. Illness perceptions, such as timeline, consequences, coherence and emotional representation, were poorly assessed. Results of the questionnaire reveal that LBP-patients report overuse, workload and bad posture as primary cause. Patients held positive beliefs about the controllability and have high illness coherence. CONCLUSION: Belgian physiotherapists mainly question bio-medically oriented illness perceptions, e.g. physical symptoms and causes, but do not sufficiently address psychosocially oriented illness perceptions as recommended in LBP guidelines. IMPLICATIONS FOR REHABILITATION: Belgian physiotherapists mainly question biomedical oriented illness perceptions (illness identity, provoking factors and treatment control) in patients with low back pain (LBP) during the history taking (i.e. the first consultation). From a bio-psycho-social view psychosocially oriented illness perceptions should be incorporated in the daily routine of physiotherapist's to comply with the bio-psycho-social treatment guidelines for LBP. Continuing education is mandatory in order to improve physiotherapists' knowledge regarding the use of all dimensions of illness perceptions in the assessment of patients with LBP.

Clinimetric properties of illness perception questionnaire revised (IPQ-R) and brief illness perception questionnaire (Brief IPQ) in patients with musculoskeletal disorders: A systematic review.

Several questionnaires are available to evaluate illness perceptions in patients, such as the illness perception questionnaire revised (IPQ-R) and the brief version (Brief IPQ). This study aims to systematically review the literature concerning the clinimetric properties of the IPQ-R and the Brief IPQ in patients with musculoskeletal pain. The electronic databases Web of Sciences and PubMed were searched. Studies were included when the clinimetric properties of the IPQ-R or Brief IPQ were assessed in adults with musculoskeletal pain. Methodological quality was determined using the COSMIN checklist. Eight articles were included and evaluated. The methodological quality was good for 3 COSMIN boxes, fair for 11 and poor for 3 boxes. None of the articles obtained an excellent methodological score. The results of this review suggest that the IPQ-R is a reliable questionnaire, except for illness coherence. Internal consistency is good, except for the causal domain. The IPQ-R has good construct validity, but the factor structure is unstable. Hence, the IPQ-R appears to be a useful instrument for assessing illness perceptions, but care must be taken when generalizing the results of adapted versions of the questionnaires. The Brief IPQ shows moderate overall test-retest reliability. No articles examining the validity of the Brief IPQ were found. Further research should therefore focus on the content and criterion validity of the IPQ-R and the clinimetric properties of the Brief IPQ.

Effect of a multidisciplinary program for the prevention of low back pain in hospital employees: a randomized controlled trial.

BACKGROUND: Hospital workers with physically demanding jobs are at risk for developing recurrent LBP. There is a lack of studies evaluating multidisciplinary prevention of low back pain (LBP) in hospital workers. OBJECTIVE: This randomized controlled trial evaluates the effect of a multidisciplinary prevention program, focusing on a client-centred approach, on hospital workers at risk for developing LBP. METHODS: Caregiving hospital workers were allocated to an experimental (12-week lasting multidisciplinary prevention program) or control group (no intervention). They were evaluated prior to the intervention and after a 6 months follow-up period. Primary outcome measures included incidence of LBP, work absenteeism and general health. Secondary outcomes included daily physical activity, job satisfaction and coping strategies. RESULTS: A significant improvement was seen for passive coping after 6 months follow-up, but no significant differences were observed between groups in primary or other secondary outcome measures (p> 0.05). CONCLUSIONS: A multidisciplinary prevention program fitting into a bio-psychosocial context may not have been intensive enough to promote a change in daily habitudes, and had no effect on work absenteeism, incidence of LBP or general health. Further research should determine whether prevention of LBP is possible in caregiving personnel.

Effect of a physical conditioning versus health promotion intervention in dancers: a randomized controlled trial.

Although dancing requires extensive physical exertion, dancers do not often train their physical fitness outside dance classes. Reduced aerobic capacity, lower muscle strength and altered motor control have been suggested as contributing factors for musculoskeletal injuries in dancers. This randomized controlled trial examined whether an intervention program improves aerobic capacity and explosive strength and reduces musculoskeletal injuries in dancers. Forty-four dancers were randomly allocated to a 4-month conditioning (i.e. endurance, strength and motor control training) or health promotion program (educational sessions). Outcome assessment was conducted by blinded assessors. When accounting for differences at baseline, no significant differences were observed between the groups following the intervention, except for the subscale "Pain" of the Short Form 36 Questionnaire (p = 0.03). Injury incidence rate and the proportion of injured dancers were identical in both groups, but dancers following the conditioning program had significant less low back injuries (p = 0.02). Supplementing regular dance training with a 4-month conditioning program does not lead to a significant increase in aerobic capacity or explosive strength in pre-professional dancers compared to a health promotion program without conditioning training, but leads to less reported pain. Further research should explore how additional training may be organized, taking into account the demanding dance schedule of pre-professional dancers. The trial is registered at ClinicalTrials.gov, number NCT01440153.

A modern neuroscience approach to chronic spinal pain: combining pain neuroscience education with cognition-targeted motor control training.

Chronic spinal pain (CSP) is a severely disabling disorder, including nontraumatic chronic low back and neck pain, failed back surgery, and chronic whiplash-associated disorders. Much of the current therapy is focused on input mechanisms (treating peripheral elements such as muscles and joints) and output mechanisms (addressing motor control), while there is less attention to processing (central) mechanisms. In addition to the compelling evidence for impaired motor control of spinal muscles in patients with CSP, there is increasing evidence that central mechanisms (ie, hyperexcitability of the central nervous system and brain abnormalities) play a role in CSP. Hence, treatments for CSP should address not only peripheral dysfunctions but also the brain. Therefore, a modern neuroscience approach, comprising therapeutic pain neuroscience education followed by cognition-targeted motor control training, is proposed. This perspective article explains why and how such an approach to CSP can be applied in physical therapist practice.

Clinical assessment of the scapula: a review of the literature.

Scientific evidence supporting a role for faulty scapular positioning in patients with various shoulder disorders is cumulating. Clinicians who manage patients with shoulder pain and athletes at risk of developing shoulder pain need to have the skills to assess static and dynamic scapular positioning and dynamic control. Several methods for the assessment of scapular positioning are described in scientific literature. However, the majority uses expensive and specialised equipment (laboratory methods), making their use in clinical practice nearly impossible. On the basis of biometric and kinematic studies, guidelines for interpreting the observation of static and dynamic scapular positioning pattern in patients with shoulder pain are provided. At this point, clinicians can use reliable clinical tests for the assessment of both static and dynamic scapular positioning in patients with shoulder pain. However, this review also provides clinicians several possible pitfalls when performing clinical scapular evaluation. On the basis of its clinical relevance, its proven reliability, its relation to body length and its applicability in a clinical setting, this review recommends to assess the scapula both static (visual observation and acromial distance or Baylor/double square method for shoulder protraction) and semidynamic (visual observation and inclinometry for scapular upward rotation). In addition, when the patient demonstrates with shoulder impingement symptoms, the scapular repositioning test and scapular assistant test are recommended for relating the patients' symptoms to the position or movement of the scapula.

Central sensitization and altered central pain processing in chronic low back pain: fact or myth?

OBJECTIVE: The purpose of this narrative review is to analyze the available literature concerning central sensitization and altered central pain processing in patients with chronic low back pain (LBP). METHODS: Literature was screened using several electronic search databases. Additional literature was obtained by reference tracking and expert consultation. Studies evaluating central pain processing in conservatively treated patients with chronic LBP were included. RESULTS: Results of studies examining the responsiveness to various stimuli in patients with chronic LBP are conflicting. Some studies in patients with chronic LBP have demonstrated exaggerated pain responses after sensory stimulation of locations outside the painful region, while other studies report no differences between patients and healthy subjects. Studies examining the integrity of the endogenous pain inhibitory systems report unaltered activity of this descending inhibitory system. In contrast, studies analyzing brain structure and function in relation to (experimentally induced) pain provide preliminary evidence for altered central nociceptive processing in patients with chronic LBP. Finally, also psychosocial characteristics, such as inappropriate beliefs about pain, pain catastrophizing, and/or depression may contribute to the mechanisms of central sensitization. CONCLUSIONS: It tempting to speculate that ongoing nociception is associated with cortical and subcortical reorganization and may play an important role in the process of the chronification of LBP. Future prospective research should explore to what extent these changes are reversible and if this reversibility is associated with improved functioning of patients.

Effects of aerobic endurance, muscle strength, and motor control exercise on physical fitness and musculoskeletal injury rate in preprofessional dancers: an uncontrolled trial.

OBJECTIVE: The purpose of this study was to evaluate musculoskeletal injury rate and physical fitness before and 6 months after an endurance, strength, and motor control exercise program in preprofessional dancers. METHODS: This uncontrolled trial was completed at a college offering a professional bachelor degree in dance. Forty preprofessional dancers underwent a test battery before and after a 6-month lasting exercise program in addition to their regular dance lessons. Physical fitness was evaluated by means of a submaximal exercise test with continuous physiological monitoring and by a field test for explosive strength. Anthropometric measurements were taken to analyze the influence of fitness training on body composition. Musculoskeletal injury incidence and quality of life were recorded during the 6-month lasting intervention. An intention-to-treat analysis ("last observation carried forward" method) was used with a Student t test for normally distributed variables. The Wilcoxon signed rank and Mann-Whitney U tests were used as nonparametric tests. RESULTS: Physical fitness improved after the 6 months of additional training program (P<.05). The waist:hip ratio (P=.036) and the sum of the measured subcutaneous skin thickness (P=.001) significantly decreased. Twelve dancers developed musculoskeletal complaints, requiring temporary interruption of dancing. CONCLUSIONS: The combination of regular dance lessons with an additional exercise program resulted in improved physical fitness in preprofessional dancers, without affecting the aesthetical appearance. A relatively high injury rate was observed during the intervention period. These results suggest that a randomized, controlled trial should be performed to examine the effectiveness of additional exercise in dancers on physical fitness and musculoskeletal injury rate.

Reduced pressure pain thresholds in response to exercise in chronic fatigue syndrome but not in chronic low back pain: an experimental study.

OBJECTIVE: The aims of this study were to examine: (i) baseline pressure pain thresholds in patients with chronic fatigue syndrome and those with chronic low back pain compared with healthy subjects; (ii) the change in mean pain threshold in response to exercise; and (iii) associations with exercise-induced increase in nitric oxide. PARTICIPANTS: Twenty-six patients with chronic fatigue syndrome suffering of chronic pain, 21 patients with chronic low back pain and 31 healthy subjects. METHODS: Participants underwent a submaximal aerobic exercise protocol on a bicycle ergometer, preceded and followed by venous blood sampling (nitric oxide) and algometry (hand, arm, calf, low back). RESULTS: Patients with chronic fatigue syndrome presented overall lower pain thresholds compared with healthy subjects and patients with chronic low back pain (p < 0.05). No significant differences were found between healthy subjects and patients with chronic low back pain. After submaximal aerobic exercise, mean pain thresholds decreased in patients with chronic fatigue syndrome, and increased in the others (p < 0.01). At baseline, nitric oxide levels were significantly higher in the chronic low back pain group. After controlling for body mass index, no significant differences were seen between the groups at baseline or in response to exercise. Nitric oxide was not related to pain thresholds in either group. CONCLUSION: The results suggest hyperalgesia and abnormal central pain processing during submaximal aerobic exercise in chronic fatigue syndrome, but not in chronic low back pain. Nitric oxide appeared to be unrelated to pain processing.

Reliability of the assessment of lumbar range of motion and maximal isometric strength in patients with chronic low back pain.

OBJECTIVE: To examine the interobserver reliability of the assessment of lumbar range of motion (ROM) and maximal isometric strength in patients with chronic low back pain (CLBP) using commercially available equipment. DESIGN: A prospective repeated-measures design. SETTING: Ambulatory care in a university hospital. PARTICIPANTS: Twelve patients (5 men, 7 women; age range, 20-52y) with CLBP, with a mean visual analog scale score of 31.5+/-25.8mm, volunteered for the study. The duration of their symptoms was 63+/-115 months and the mean Oswestry Disability Index score was 31%. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Movements of the lumbar spine were assessed with commercially available equipment. Both the range of motion (ROM) and the maximal isometric strength for flexion, extension, lateroflexion, and rotation of the lumbar spine were evaluated twice to analyze the interobserver reliability. The same test procedure was performed on 2 separate days by 2 investigators who were blinded to the outcome of the assessment of their colleague. The order of investigator was balanced, so that each investigator tested the same number of patients as first investigator. RESULTS: The intraclass correlation coefficient varied between .91 and .98 for the measurements of the lumbar ROM and was between .93 and .97 for all the strength measurements. Post hoc power analysis confirmed previous power analysis, that is, despite the small sample size, an excellent power was found for the observed interobserver reliability coefficients (power range, 0.93-1.00). No learning effect was found when comparing the results of the second measurement with the first measurement (P>.05). CONCLUSIONS: The interobserver reliability is excellent for the measurement of the ROM of the lumbar spine and for the maximal isometric strength using specific devices in patients with CLBP.

Low back pain: clinimetric properties of the Trendelenburg test, active straight leg raise test, and breathing pattern during active straight leg raising.

OBJECTIVE: Classification of patients with low back pain (LBP) into subgroups is important as considerable variability exists in the LBP population. Clinical applicable, reliable, and valid tests to differentiate patients with LBP are therefore necessary. The purpose of this study is to examine the reliability, internal consistency, and clinical importance of 3 clinical tests that analyze motor control mechanisms of the lumbopelvic region in patients with nonspecific LBP. METHODS: Thirty-six patients with chronic nonspecific LBP volunteered for the study (cross-sectional design). The patients were examined by 2 assessors who were blinded to the results of each other. The following tests were performed: the Trendelenburg test, the active straight leg raise (ASLR) test, and the ASLR with visual inspection of the breathing pattern. RESULTS: The test-retest reliability coefficients (kappa) were greater than 0.75 for the Trendelenburg score and greater than 0.70 for the ASLR. The interobserver reliability coefficients were greater than 0.39 for the assessment of the breathing pattern during the ASLR. The Cronbach alpha coefficient for internal consistency of the Trendelenburg and ASLR tests was greater than .73. No significant associations were found between the outcome of the tests and self-reported pain severity or disability. CONCLUSIONS: These data provide evidence favoring the test-retest reliability of the Trendelenburg and ASLR tests in patients with LBP. The internal consistency of the outcome of these tests was high for both assessors, suggesting that these tests assess the same dimension. The interobserver reliability of the assessment of the breathing pattern was fair to moderate. Further research regarding the interobserver reliability, clinical importance, validity, and responsiveness of the Trendelenburg test, ASLR test, and breathing pattern during these tests is required.