Predictive validity of initial fear avoidance beliefs in patients with low back pain receiving physical therapy: is the FABQ a useful screening tool for identifying patients at risk for a poor recovery?

Several prospective studies examining patients receiving physical therapy support the predictive validity of FABQ subscale scores. This has lead to the proposition that the FABQ would be a useful screening tool, permitting early identification of patients at risk for a poor outcome with an opportunity to modify the treatment accordingly. However, the predictive validity of the FABQ within physical therapy practice has yet to be examined. Predictive validity was analyzed between the FABQ-PA, FABQ-W using both disability and pain as the dependent variables using Pearson correlation coefficients and stepwise hierarchical linear regression modeling controlling for baseline variables. Separate analyses were run for patients with private health insurance and those receiving workers’ compensation. Further analysis of predictive validity was performed by dichotomizing the outcome of physical therapy. Patients were coded as having a poor outcome if they failed to achieve a minimum clinically important change in disability over the course of treatment. The accuracy of previously reported cut-off scales for both the FABQ-W and FABQ-PA were examined for both payor types. Results of the hierarchical linear regression analyses for patients with private insurance showed neither the FABQ-PA nor the FABQ-W score significantly improved the explained variance in change in pain or disability. For patients receiving workers’ compensation, only the FABQ-W subscale score significantly contributed to the model after controlling for the other baseline variables for both changes in disability and pain. Only the FABQ-W subscale was predictive of poor outcome and this was only identified in the worker’s compensation group. The results suggest that the work subscale of the FABQ might be an appropriate screening tool to identify patients with work-related LBP who are at risk for a poor outcome with routine physical therapy. Neither FABQ subscale was predictive of outcome for patients with private insurance, and the use of the FABQ, as a screening tool for patients with non-work-related LBP was not supported. The handling of data in this study was performed in compliance with the current laws of the United States of America inclusive of ethics approval.     

Neck and back pain specific outcome assessment questionnaires in the Spanish language: a systematic literature review

Background contextAccurate measurement of functional improvement in clinical practice is becoming increasingly recognized as essential in demonstrating whether patients are deriving meaningful benefit from care. Several simple questionnaires have been developed for this purpose. The majority of these have been developed in English. In North America, there is a growing need for clinical tools, including outcome assessment tools that are available in the Spanish language.PurposeThe purpose of this study was to systematically review the literature regarding spine-specific outcome assessment questionnaires that are available in Spanish and to examine the evidence on their clinical utility.Study designSystematic review.MethodsThe Medline, CINAHL, Embase, and MANTIS databases were searched for any studies on the topic of outcome assessment questionnaires in the Spanish language. Relevant articles were reviewed, and the data on reliability, validity, time to completion, and any other properties of the questionnaire was extracted.ResultsThe search strategy identified 287 articles, of which 10 were deemed relevant. With regard to neck pain, data were found regarding Spanish translations of the Northwick Park Neck Pain Questionnaire, Neck Disability Index (NDI), and Core Outcome Measure for neck pain. With regard to low back pain, data were found regarding Spanish translations of the Oswestry Low Back Pain Disability Index (ODI), Roland Morris Disability Questionnaire (RMQ), and the North American Spine Society—American Academy of Orthopedic Surgeons questionnaire.ConclusionsSeveral reliable and valid outcome assessment questionnaires are available in the Spanish language. All were originally developed in English. It appears from the data reviewed that the most useful instruments are the NDI for neck pain patients and the ODI and RMQ for low back pain patients. The current trend is for the development of culturally adapted versions of these questionnaires that are specific to a particular country or region.     

The role of fear avoidance beliefs as a prognostic factor for outcome in patients with nonspecific low back pain: a systematic review

Background contextPsychological factors including fear avoidance beliefs are believed to influence the development of chronic low back pain (LBP).PurposeThe purpose of this study was to determine the prognostic importance of fear avoidance beliefs as assessed by the Fear Avoidance Beliefs Questionnaire (FABQ) and the Tampa Scale of Kinesiophobia for clinically relevant outcomes in patients with nonspecific LBP.Design/settingThe design of this study was a systematic review.MethodsIn October 2011, the following databases were searched: BIOSIS, CINAHL, Cochrane Library, Embase, OTSeeker, PeDRO, PsycInfo, PubMed/Medline, Scopus, and Web of Science. To ensure the completeness of the search, a hand search and a search of bibliographies was conducted and all relevant references included. A total of 2,031 references were retrieved, leaving 566 references after the removal of duplicates. For 53 references, the full-text was assessed and, finally, 21 studies were included in the analysis.ResultsThe most convincing evidence was found supporting fear avoidance beliefs to be a prognostic factor for work-related outcomes in patients with subacute LBP (ie, 4 weeks–3 months of LBP). Four cohort studies, conducted by disability insurance companies in the United States, Canada, and Belgium, included 258 to 1,068 patients mostly with nonspecific LBP. These researchers found an increased risk for work-related outcomes (not returning to work, sick days) with elevated FABQ scores. The odds ratio (OR) ranged from 1.05 (95% confidence interval [CI] 1.02–1.09) to 4.64 (95% CI, 1.57–13.71). The highest OR was found when applying a high cutoff for FABQ Work subscale scores. This may indicate that the use of cutoff values increases the likelihood of positive findings. This issue requires further study. Fear avoidance beliefs in very acute LBP (<2 weeks) and chronic LBP (>3 months) was mostly not predictive.ConclusionsEvidence suggests that fear avoidance beliefs are prognostic for poor outcome in subacute LBP, and thus early treatment, including interventions to reduce fear avoidance beliefs, may avoid delayed recovery and chronicity.     

Differences in electromyographic activity in the multifidus muscle and the iliocostalis lumborum between healthy subjects and patients with sub-acute and chronic low back pain

The present study was carried out to examine possible mechanisms of back muscle dysfunction by assessing a stabilising and a torque-producing back muscle, the multifidus (MF) and the iliocostalis lumborum pars thoracis (ICLT), respectively, in order to identify whether back pain patients showed altered recruitment patterns during different types of exercise. In a group of healthy subjects (n=77) and patients with sub-acute (n=24) and chronic (51) low back pain, the normalised electromyographic (EMG) activity of the MF and the ICLT (as a percentage of maximal voluntary contraction) were analysed during coordination, stabilisation and strength exercises. The results showed that, in comparison with the healthy subjects, the chronic low back pain patients displayed significantly lower (P=0.013) EMG activity of the MF during the coordination exercises, indicating that, over the long term, back pain patients have a reduced capacity to voluntarily recruit the MF in order to obtain a neutral lordosis. In contrast, during the stabilisation exercises, no significant differences between patients and controls were found for the normalised EMG activity of the two muscles. These findings indicated that, during low-load exercises, no insufficiencies in back muscle recruitment were evident in either subacute or chronic back pain patients. During the strength exercises, the normalised activity of both back muscles was significantly lower in chronic low back pain patients (P=0.017 and 0.003 for the MF and ICLT, respectively) than in healthy controls. Pain, pain avoidance and deconditioning may have contributed to these lower levels of EMG activity during intensive back muscle contraction. The possible dysfunction of the MF during coordination exercises and the altered activity of both muscles during strength exercises may be of importance in symptom generation, recurrence or maintenance of low back pain.     

Reliability and validity of the cross-culturally adapted French version of the Core Outcome Measures Index (COMI) in patients with low back pain

Purpose  

To conduct a cross-cultural adaptation of the Core Outcome Measures Index (COMI) into French according to established guidelines.     

Spine stabilisation exercises in the treatment of chronic low back pain: a good clinical outcome is not associated with improved abdominal muscle function

Introduction

Various studies have shown that spine stabilisation exercise therapy elicits improvements in symptoms/disability in patients with chronic non-specific low back pain (cLBP). However, few have corroborated the intended mechanism of action by examining whether clinical improvements (1) are greater in patients with functional deficits of the targeted muscles and (2) correlate with post-treatment improvements in abdominal muscle function.

Methods

Pre and directly after 9 weeks’ therapy, 32 cLBP patients (44.0 ± 12.3 years) rated their LBP intensity (0–10) and disability (0–24, Roland–Morris; RM) and completed psychological questionnaires. At the same timepoints, the voluntary activation of transversus abdominis (TrA), obliquus internus and obliquus externus during “abdominal-hollowing” and the anticipatory (“feedforward”) activation of these muscles during rapid arm movements were measured using M-mode ultrasound with tissue Doppler imaging.

Results

Pre-therapy to post-therapy, RM decreased from 8.9 ± 4.7 to 6.7 ± 4.3, and average pain, from 4.7 ± 1.7 to 3.5 ± 2.3 (each P < 0.01). The ability to voluntarily activate TrA increased by 4.5% (P = 0.045) whilst the anticipatory activation of the lateral abdominal muscles showed no significant change (P > 0.05). There was no significant correlation between the change in RM scores after therapy and either baseline values for voluntary (r = 0.24, P = 0.20) or anticipatory activation (r = 0.04, P = 0.84), or their changes after therapy (voluntary, r = 0.08, P = 0.66; anticipatory, r = 0.16, P = 0.40). In multiple regression, only a reduction in catastrophising (P = 0.0003) and in fingertip–floor distance (P = 0.0006) made unique contributions to explaining the variance in the reduction in RM scores.

Conclusion

Neither baseline lateral abdominal muscle function nor its improvement after a programme of stabilisation exercises was a statistical predictor of a good clinical outcome. It is hence difficult to attribute the therapeutic result to any specific effects of the exercises on these trunk muscles. The association between changes in catastrophising and outcome serves to encourage further investigation on larger groups of patients to clarify whether stabilisation exercises have some sort of “central” effect, unrelated to abdominal muscle function per se.     

Movement coordination of the lumbar spine and hip during a picking up activity in low back pain subjects

The effect of low back pain, with or without nerve root signs, on the joint coordination and kinematics of the lumbar spine and hips during everyday activities, such as picking up an object from the floor, are largely unknown. An experimental study was designed to compare lumbar spine and hip joint kinematics and coordination in subjects with and without sub-acute low back pain, while picking up an object in a sitting position. A three-dimensional real-time electromagnetic tracking device was used to measure movements of the lumbar spine and hips. Sixty participants with subacute low back pain, with or without straight leg raise signs, and twenty healthy asymptomatic participants were recruited. The ranges of motions of lumbar spine and hips were determined. Movement coordination between the two regions was examined by cross-correlation. Results showed that mobility was significantly reduced in subjects with back pain, who compensated for limited motion through various strategies. The contribution of the lumbar spine relative to that of the hip was, however, found to be similar in all groups. The lumbar spine–hip joint coordination was substantially altered in subjects with back pain, in particular, those with a positive straight leg raise sign. We conclude that changes in the lumbar and hip kinematics were related to back pain and limitation in straight leg raise. Lumbar–hip coordination was mainly affected by the presence of positive straight leg raise sign when picking up an object in a sitting position.     

腰痛患者下腰椎MRI上Modic改变与高信号区的发生情况及意义

目的:探讨腰痛患者下腰椎MRI上Modic改变与腰椎间盘局限性高信号区(high-intensity zone,HIZ)的发生情况及意义。方法:对511例腰痛患者(男263例,女248例;年龄20~70岁,平均48岁)腰椎MRI上L4/5和L5/S1节段的Modic改变和HIZ进行评估,统计两者及两者共存于同一节段的发生率。将有Modic改变和/或HIZ的椎间盘分为Modic组、Modic-HIZ组、HIZ组,比较3组的年龄、椎间盘高度、椎间盘退变程度、腰痛VAS和ODI评分。结果:511例患者中,190例(37.18%)209个节段有Modic改变,127例(24.85%)142个椎间盘有HIZ,18例(3.52%)18个节段出现Modic改变和HIZ共存的现象。HIZ组、Modic-HIZ组和Modic组分别为89例(124个节段)、18例(18个节段)、152例(191个节段),患者平均年龄分别为46.0±11.0岁、49.2±9.2岁和53.5±10.6岁,仅HIZ组和Modic组差异有统计学意义(P<0.05);椎间盘平均高度分别为9.93±2.46mm、8.73±2.45mm和7.57±2.21mm,组间两两比较差异有统计学意义(P<0.05);3组椎间盘退变分级均≥Ⅲ级,其中Ⅳ级+Ⅴ级退变率分别为48.39%、72.22%和75.92%,仅HIZ组与Modic组、Modic-HIZ组差异有统计学意义(P<0.05);腰痛VAS分别为8.39±0.32分、8.45±0.30分、8.61±0.54分,ODI评分分别为38.22±4.23分、38.45±4.16分、39.18±3.53分,3组间无统计学差异(P>0.05)。结论:腰痛患者下腰椎Modic改变和HIZ的发生率较高,但两者共存于同一节段的发生率低,当两者共存于同一节段时腰痛并不会明显加重。     

Magnetic resonance imaging of the lumbar spine: determining clinical impact and potential harm from overuse

Background

Lumbar spine magnetic resonance imaging is frequently said to be “overused” in the evaluation of low back pain, yet data concerning the extent of overuse and the potential harmful effects are lacking.

Self reported health status and magnetic resonance imaging findings in patients with low back pain

The authors present a prospective study of quality of life (SF-36) and MRI findings in patients with low back pain (LBP). Disc herniation and nerve root compression contribute to LBP and poor quality of life. However, significant proportions of asymptomatic subjects have disc herniation and neural compromise. Little is known about the influence of disc abnormalities and neural compression on quality of life in symptomatic patients. The purpose of this study was to assess the relationship between the extent of disc abnormality, neural impingement and quality of life. A total of 317 consecutive patients with LBP referred for MRI completed an SF-36 health status questionnaire immediately before imaging and again 6 months later. Patients were grouped according to the most extensive disc abnormality and any neural compromise reported at MRI. The relationship between symptoms, radiological signs and SF-36 scores was assessed. Eighty percent (255/317) and 65% (205/317) of patients completed the initial and 6-month SF-36, respectively. Thirty-six percent of patients (115/317) had one or more herniated discs and 44% (140/317) had neural impingement. There was little relationship between the extent of disc abnormality and quality of life. Patients with radiological evidence of neural impingement reported better general health (P < 0.01). SF-36 scores improved at 6 months in four dimensions, but general health deteriorated (P < 0.01). Patients with neural impingement had improved pain scores at 6 months (P < 0.05). The study results showed that the pain and dysfunction caused by disc herniation and neural compromise are not sufficiently distinct from other causes of back pain to be distinguished by the SF-36. Whilst neural compromise may be the best radiological feature distinguishing patients who may benefit from intervention, it cannot predict quality of life deficits in the diffuse group of patients with LBP. Received: 8 January 1998 Revised: 16 April 1998 Accepted: 24 April 1998     

Spinal alignment in low back pain patients and age-related side effects: a multivariate cross-sectional analysis of video rasterstereography back shape reconstruction data

Purpose

Spinal form in the sagittal plane and asymmetries of spinal alignment in the frontal plane were identified earlier to be associated with low back pain. This study was aiming at investigating whether age was influencing the significance of these findings.

Methods

Spinal alignment of 155 older and 58 younger low back pain patients was investigated using non-invasive video rasterstereography and compared to 192 pain free controls. Trunk inclination and imbalance, pelvis tilt and torsion, and the thoracic kyphosis and lumbar lordosis angle served as dependent variables, which were analyzed using multivariate procedures.

Results

Frontal plane parameters—trunk imbalance (λ > 0.60) in combination with pelvis tilt (λ > 0.64)—constituted an independent component in a factor analysis model of spine shape parameters in younger and older patients, but not in pain free controls. Trunk imbalance (frontal), trunk inclination (sagittal) and partially thoracic kyphosis angle (sagittal) were extracted to separate patients from controls (discriminant coefficients >0.50). Age could not be excluded as interfering variable for the lumbar lordosis angle. Significant univariate analyses revealed higher effect sizes for trunk imbalance and inclination (η ² > 0.07) than for lordosis, kyphosis or pelvic parameters (η ² < 0.06).

Conclusions

In line with corresponding findings trunk imbalance remained a low back pain-associated parameter not depending on age. Over all, sagittal trunk inclination and the thoracic kyphosis angle could not be established as being completely free from age influences, while the lumbar lordosis angle played a minor role and seemed to be influenced more by age than by low back pain in this rasterstereography study.     

Lumbar motion changes in chronic low back pain patients: a secondary analysis of data from a randomized clinical trial

Background contextSeveral therapies have been used in the treatment of chronic low back pain (LBP), including various exercise strategies and spinal manipulative therapy (SMT). A common belief is that spinal motion changes in particular ways in direct response to specific interventions, such as exercise or spinal manipulation.PurposeThe purpose of this study was to assess changes in lumbar region motion for more than 12 weeks by evaluating four motion parameters in the sagittal plane and two in the horizontal plane in LBP patients treated with either exercise therapy or spinal manipulation.Study design/settingSecondary analysis of a subset of participants from a randomized clinical trial.Patient sampleOne hundred ninety-nine study participants with LBP of more than 6 weeks' duration who had spinal motion measures obtained before and after the period of intervention.Outcome measuresLumbar region spinal kinematics sampled using a six-degree-of-freedom instrumented spatial linkage system.MethodsTrained therapists collected regional lumbar spinal motion data at baseline and 12 weeks of follow-up. The lumbar region spinal motion data were analyzed as a total cohort and relative to treatment modality (high dose, supervised low-tech trunk exercise, SMT, and a short course of home exercise and self-care advice). The study was supported by grants from Health Resources and Services Administration, Danish Agency for Science Technology and Innovation, Danish Chiropractors Research Foundation, and the University of Southern Denmark. No conflicts of interest reported.ResultsFor the cohort as a whole, lumbar region motion parameters were altered over the 12-week period, except for the jerk index parameter. The group receiving spinal manipulation changed significantly in all, and the exercise groups in half, the motion parameters included in the analysis. The spinal manipulation group changed to a smoother motion pattern (reduced jerk index), whereas the exercise groups did not.ConclusionThis study provides evidence that spinal motion changes can occur in chronic LBP patients over a 12-week period and that these changes are associated with the type of treatment.     

Cross-cultural adaptation and validation of the NASS outcomes instrument in Spanish patients with low back pain

Objectives: The aim of the study was to evaluate validity, reliability, responsiveness and practicality of the NASS-AAOS (North American Spine Society—American Academy of Orthopaedic Surgeons) questionnaire in patients with low back pain. Methods: The sample included 70 patients with herniated disk, stenosis, chronic low back pain of unknown etiology or acute low back pain. They were assessed twice before treatment (test–retest) and a third measure six months to one year afterwards. Results: The mean time of administration was 24 and 20 min for the test and post-treatment evaluation, respectively. Cronbachs alpha coefficient was between 0.78 and 0.92 on the baseline test and 0.90 or higher on the post-treatment evaluation. The test–retest reproducibility was 0.95 (0.91–0.98) for neurological symptoms, 0.82 (0.63–0.91) for pain/disability and 0.63 (0.25–0.82) for expectations. The associations with other measures and clinical criteria were generally moderate to high and in the expected direction. The effect size for pain/disability in combination with neurological symptoms was 2.02 for patients who improved versus an effect of –0.09 in patients who were stable between test and retest; the area under the curve on this joint scale was 0.81 (0.69–0.90). Conclusions: The instrument is valid, sensitive to clinical changes and reliable for comparisons between groups, but further study is needed for its application in monitoring individual patients.     

腰背肌筋膜痛综合征核心肌群的表面肌电信号与肌纤维类型的相关性分析

目的:运用表面肌电检测腰背肌筋膜痛患者腰部核心肌群,通过中位频率及中位频率斜率的分析,判断其肌纤维类型分布规律。方法:2017年10月至2018年3月100例腰背肌筋膜炎患者,男45例,女55例;年龄29～76岁,平均48.5岁;左侧腰背疼痛(左侧疼痛组)40例,右侧腰背疼痛(右侧疼痛组)60例;病程6个月。另有40例腰部无疼痛健康人为对照组,男20例,女20例;年龄29～76岁,平均47.3岁。患者均有不同程度的背部酸痛及背部肌肉僵硬,经临床和影像学检查诊断为腰背肌筋膜炎。使用表面肌电测量3组人群的腰部核心肌肉(多裂肌、髂肋肌、最长肌)在腰背肌等长收缩试验过程中的肌电信号特征,如中位频率及中位频率斜率绝对值。结果:3组多裂肌的中位频率,对照组左侧(133.88±26.61)μV,右侧(131.39±29.81)μV;左侧疼痛组左侧(117.29±10.93)μV,右侧(133.70±17.81)μV;右侧疼痛组左侧(131.36±17.37)μV,右侧(118.28±13.57)μV。3组髂肋肌的中位频率,对照组左侧(106.94±28.01)μV,右侧(114.68±18.96)μV;左侧疼痛组左侧(93.95±11.17)μV,右侧(107.60±27.86)μV;右侧疼痛组左侧(105.93±15.52)μV,右侧(97.27±19.27)μV。3组最长肌的中位频率,对照组左侧(109.24±26.20)μV,右侧(112.58±17.70)μV;左侧疼痛组左侧(95.58±10.83)μV,右侧(108.79±26.39)μV;右侧疼痛组左侧(106.50±17.98)μV,右侧(98.20±11.16)μV。3组多裂肌的中位频率斜率绝对值,对照组左侧0.221±0.109,右侧0.259±0.169;左侧疼痛组左侧0.318±0.184,右侧0.210±0.159;右侧疼痛组左侧0.258±0.169,右侧0.386±0.166。3组髂肋肌的中位频率斜率绝对值,对照组左侧0.241±0.158,右侧0.238±0.128;左侧疼痛组左侧0.330±0.208,右侧0.252±0.171;右侧疼痛组左侧0.249±0.150,右侧0.343±0.144。3组最长肌的中位频率斜率绝对值,对照组左侧0.244±0.252,右侧0.210±0.128;左侧疼痛组左侧0.348±0.255,右侧0.241±0.224;右侧疼痛组左侧0.239±0.155,右侧0.334±0.233。对照组左右侧腰多裂肌、髂肋肌、最长肌的中位频率和中位频率斜率绝对值差异无统计学意义(P0.05);腰痛组疼痛侧多裂肌、髂肋肌、最长肌的中位频率值小于非疼痛侧(P0.05),中位频率斜率绝对值大于非疼痛侧(P0.05)。结论:慢性腰背筋膜痛患者疼痛侧的腰部肌肉耐疲劳程度下降,肌纤维类型百分比转变为以Ⅱ型肌纤维为主。     

Neck and shoulder pain in 70- to 79-year-old men and women: findings from the Health, Aging and Body Composition Study

BACKGROUND CONTEXT: Musculoskeletal pain in the cervicobrachial region is considered a major health problem among adults of working age, but little is known about the impact of this pain in the elderly. PURPOSE: Determine the prevalence of neck and shoulder pain in a well-functioning cohort, identify factors associated with this pain, assess the pattern of coexisting joint pain and evaluate the impact of this pain on physical functioning. STUDY DESIGN: Cross-sectional study. PATIENT SAMPLE: Black and white men and women, aged 70 to 79 years, participating in the Health, Aging and Body Composition (Health ABC) study. OUTCOME MEASURES: Not applicable. METHODS: Between April 1997 and June 1998, 3,075 men and women participating in Health ABC study completed the initial home interview and clinical examination. Information was collected on musculoskeletal pain, medical history, depressive symptomatology and physical function. Physical performance measures were obtained. RESULTS: A total of 11.9% of participants reported neck pain of one month or more in duration and 18.9% reported shoulder pain. White women had the highest prevalence of neck pain (15.4%) and black women the highest prevalence of shoulder pain (24.3%). The correlates of both neck and shoulder pain were female gender, no education beyond high school, poorer self-rated health, depressive symptomatology and a medical history of arthritis, heart attack, angina. Increasing severity of both neck and shoulder pain was associated with an increased prevalence of joint pain at other body sites and with poor functional capacity. Measures of physical performance involving the upper extremity were also decreased. CONCLUSIONS: Neck and shoulder pain, either alone or in conjunction with pain in other joints, has a substantial impact on the function and well-being of the older adults in this cohort.     

Effects of noxious stimulation and pain expectations on neuromuscular control of the spine in patients with chronic low back pain

Background context

Alterations of the neuromuscular control of the lumbar spine have been reported in patients with chronic low back pain (LBP). During trunk flexion and extension tasks, the reduced myoelectric activity of the low back extensor musculature observed during full trunk flexion is typically absent in patients with chronic LBP.

Purpose

To determine whether pain expectations could modulate neuromuscular responses to experimental LBP to a higher extent in patients with chronic LBP compared with controls.

Study design

A cross-sectional, case-control study.

Patient sample

Twenty-two patients with nonspecific chronic LBP and 22 age- and sex-matched control participants.

Methods

Trunk flexion-extension tasks were performed under three experimental conditions: innocuous heat, noxious stimulation with low pain expectation, and noxious stimulation with high pain expectation. Noxious stimulations were delivered using a contact heat thermode applied on the skin of the lumbar region (L4–L5), whereas low or high pain expectations were induced by verbal and visual instructions.

Outcome measures

Surface electromyography of erector spinae at L2–L3 and L4–L5, as well as lumbopelvic kinematic variables were collected during the tasks. Pain was evaluated using a numerical rating scale. Pain catastrophizing, disability, anxiety, and fear-avoidance beliefs were measured using validated questionnaires.

Results

Two-way mixed analysis of variance revealed that pain was significantly different among the three experimental conditions (F2,84=317.5; p<.001). Increased myoelectric activity of the low back extensor musculature during full trunk flexion was observed in the high compared with low pain expectations condition at the L2–L3 level (F2,84=9.5; p<.001) and at the L4–L5 level (F2,84=3.7; p=.030). At the L4–L5 level, this effect was significantly more pronounced for the control participants compared with patients with chronic LBP (F2,84=3.4; p=.045). Pearson correlation analysis revealed that increased lumbar muscle activity in full flexion induced by expectations was associated with higher pain catastrophizing in patients with chronic LBP (r=0.54; p=.012).

Conclusions

Repeated exposure to pain appears to generate rigid and less variable patterns of muscle activation in patients with chronic LBP, which attenuate their response to pain expectations. Patients with high levels of pain catastrophizing show higher myoelectric activity of lumbar muscles in full flexion and exhibit greater neuromechanical changes when expecting strong pain.     

A national media mass campaign improves beliefs and behaviours about low back pain in the general population and in general practitioners

IntroductionPrevious international mass-media campaigns for low back pain (LBP) have had conflicting impacts on the general population. The objective was to evaluate the impact of a national back pain campaign conducted between 2017 and 2019 on beliefs and behaviours of general practitioners and the general population in France.MethodsBetween 2017 and 2019, a mass-media campaign was used to disseminate positive messages about LBP using several media, along with a parallel campaign addressed to general practitioners. An email survey before the campaign and 6 and 18 months after the campaign started evaluated beliefs and behaviours among a representative sample of the 2 target populations (3500 people from the general population and 700 general practitioners before the campaign, and 2000 people and 300 general practitioners 6 and 18 months after).ResultsOverall, 56% of the general population respondents before the campaign and 74% and 75% at 6 and 18 months after adhered to the statement “One should maintain physical activity” when dealing with LBP. Conversely, the percentage adhering to the statement “The best treatment is resting” decreased significantly from 68% before the campaign to 45% at 6 and 18 months after. Physicians reported delivering more reassurance and giving more documentation to patients after the campaign. They prescribed less sick leave during the first consultation (65% before the campaign, 46% and 30% at 6 and 18 months after).ConclusionA mass-media campaign aimed at the public and general practitioners in France significantly modified beliefs and behaviours about LBP.