Association between physical activity,sedentary behaviour and the trajectory of low back pain

BACKGROUNDLow back pain (LBP) is one of the world's most prevalent health issues. Patients with LBP experience various intensities and durations of symptoms, which can lead to distinctive course patterns commonly described as symptom trajectories.PURPOSEThis study aimed to investigate the association between different amounts of physical activity and sedentary behavior and the trajectory of LBP, in people with a lifetime history of LBP.STUDY DESIGNThe study involved a secondary analysis of observational longitudinal data collected from the AUstralian Twin low BACK pain (AUTBACK) study.METHODSA total of 329 individual twins met the inclusion criteria for analysis. Latent Class Growth Analysis was used to identify distinct patterns of LBP and select the primary outcome (probability of having a severe LBP trajectory, 0%–100%). Linear regression models were used to investigate the association between different amounts of physical activity or sedentary behavior at baseline, and the probability of having a severe LBP trajectory. Results were expressed as β coefficients and 95% confidence intervals (CI).RESULTSModerate-to-vigorous intensity physical activity was significantly associated with the probability of having a severe LBP trajectory (unadjusted β -0.0276; 95%CI -0.0456 to -0.0097, p=.003). For every 1-minute increase in moderate-to-vigorous intensity physical activity per week, there was a 2.8%-point reduction in a participant's probability of having a severe LBP trajectory. No significant associations were identified between sedentary behavior or light intensity physical activity, and the probability of having a severe LBP trajectory.CONCLUSIONSIn people with a lifetime history of LBP, engagement in higher volumes of moderate to vigorous intensity physical activity at baseline was associated with a lower probability of developing a severe trajectory of LBP over 1 year.     

Exercise attenuates low back pain and alters epigenetic regulation in intervertebral discs in a mouse model

BACKGROUND CONTEXTChronic low back pain (LBP) is a multifactorial disorder with complex underlying mechanisms, including associations with intervertebral disc (IVD) degeneration in some individuals. It has been demonstrated that epigenetic processes are involved in the pathology of IVD degeneration. Epigenetics refers to several mechanisms, including DNA methylation, that have the ability to change gene expression without inducing any change in the underlying DNA sequence. DNA methylation can alter the entire state of a tissue for an extended period of time and thus could potentially be harnessed for long-term pain relief. Lifestyle factors, such as physical activity, have a strong influence on epigenetic regulation. Exercise is a commonly prescribed treatment for chronic LBP, and sex-specific epigenetic adaptations in response to endurance exercise have been reported. However, whether exercise interventions that attenuate LBP are associated with epigenetic alterations in degenerating IVDs has not been evaluated.PURPOSEWe hypothesize that the therapeutic efficacy of physical activity is mediated, at least in part, at the epigenetic level. The purpose of this study was to use the SPARC-null mouse model of LBP associated with IVD degeneration to clarify (1) if IVD degeneration is associated with altered expression of epigenetic regulatory genes in the IVDs, (2) if epigenetic regulatory machinery is sensitive to therapeutic environmental intervention, and (3) if there are sex-specific differences in (1) and/or (2).STUDY DESIGNEight-month-old male and female SPARC-null and age-matched control (WT) mice (n=108) were assigned to exercise (n=56) or sedentary (n=52) groups. Deletion of SPARC is associated with progressive IVD degeneration and behavioral signs of LBP. The exercise group received a circular plastic home cage running wheel on which they could run freely. The sedentary group received an identical wheel secured in place to prevent rotation. After 6 months, the results obtained in each group were compared.METHODSAfter 6 months of exercise, LBP-related behavioral indices were determined, and global DNA methylation (5-methylcytosine) and epigenetic regulatory gene mRNA expression in IVDs were assessed. This project was supported by the Canadian Institutes for Health Research. The authors have no conflicts of interest.RESULTSLumbar IVDs from WT sedentary and SPARC-null sedentary mice had similar levels of global DNA methylation (%5-mC) and comparable mRNA expression of epigenetic regulatory genes (Dnmt1,3a,b, Mecp2, Mbd2a,b, Tet1-3) in both sexes. Exercise attenuated LBP-related behaviors, decreased global DNA methylation in both WT (p<.05) and SPARC-null mice (p<.01) and reduced mRNA expression of Mecp2 in SPARC-null mice (p<.05). Sex-specific effects of exercise on expression of mRNA were also observed.CONCLUSIONSExercise alleviates LBP in a mouse model. This may be mediated, in part, by changes in the epigenetic regulatory machinery in degenerating IVDs. Epigenetic alterations due to a lifestyle change could have a long-lasting therapeutic impact by changing tissue homeostasis in IVDs.CLINICAL SIGNIFICANCEThis study confirmed the therapeutic benefits of exercise on LBP and suggests that exercise results in sex-specific alterations in epigenetic regulation in IVDs. Elucidating the effects of exercise on epigenetic regulation may enable the discovery of novel gene targets or new strategies to improve the treatment of chronic LBP.     

Low back pain among medical students

Low back pain (LBP) is known to affect both older and younger adults. Medical schools tend to have time-consuming curricula, possibly perpetuating a sedentary lifestyle, and a high prevalence of LBP among medical students. The purpose of this study was to evaluate the extent of sedentary lifestyle and the 12-month prevalence of LBP in a sample group of medical students in comparison to a random sample of physical education students. A retrospective study involving a questionnaire-based inquiry of 103 medical students showed that they were approximately 2.5 times less physically active than the 107 physical education students (p < 0.001) and spent 3 more hours per day sitting (p < 0.001). The 12-month prevalence of (sub)acute and chronic LBP in the sample group of medical students was 53.4% (95% CI: 43.8%-63.0%), as compared to 60.7% (95% CI: 51.4% -70.0%) in the sample group of physical education students, yielding no statistically significant difference (p = 0.329). These data reveal a high prevalence of low back pain among students, which is rather alarming considering their young age. Strangely, the prevalence of LBP was not higher in medical students than in physically more active students, in spite of their sedentary lifestyle. According to the literature, the sitting position is no longer considered as a risk factor for low back pain.     

Adaptation of muscles of the lumbar spine to sudden imbalance in patients with lower back pain caused by military training

Abstract

Objective

This study aims to investigate the effects of sudden load changes (expected and unexpected imbalance) on the activity of muscles of the lumbar spine and their central motor control strategy in military personnel with or without chronic low back pain (LBP).

Design

Bilateral sudden imbalance was examined (2 × 2 factorial design).

Setting

The 117th PLA Hospital, Hangzhou, China

Participants

Twenty-one male subjects with lower back pain and 21 male healthy control subjects were active members of the Nanjing Military Region land forces.

Outcome measures

Independent variables: LBP vs. healthy controls and imbalance anticipation (expected and unexpected imbalance). Dependent variables: rapid reaction time (RRT) and intensity of rapid reaction (IRR) of bilateral lumbar (L3–L4) erector spinae (ES), lumbar (L5–S1) multifidus (MF), and abdominal external oblique muscles.

Results

Under expected or unexpected sudden imbalance conditions, subjects with LBP demonstrated significantly greater IRR than healthy controls in ipsilateral and contralateral ES and MF, respectively (P < 0.05 for all). IRR of contralateral ES was significantly larger than that of the ipsilateral ES. A significant group effect of RRT of both ipsilateral and contralateral ES muscles and a significant time expectation effect on RRT of contralateral MF muscles were also observed. RRT of the contralateral ES muscles was significantly lower than that of the ipsilateral ES muscles (P < 0.001).

Conclusions

Sudden imbalance prolonged RRT of selected trunk muscles in patients with chronic LBP. The activation amplitude increased. The results may provide a theoretical basis for a study on the pathogenesis of chronic LBP.     

Fear of movement is not associated with trunk movement variability during gait in patients with low back pain

BACKGROUNDLiterature describing differences in motor control between low back pain (LBP) patients and healthy controls is very inconsistent, which may be an indication for the existence of subgroups. Pain-related psychological factors might play a role causing these differences.PURPOSETo examine the relation between fear of movement and variability of kinematics and muscle activation during gait in LBP patients.STUDY DESIGNCross-sectional experimental design.PATIENT SAMPLEThirty-one Chinese LBP patients.OUTCOME MEASURESSelf-report measures: Visual Analog Score for pain; TAMPA-score; Physiologic measures: electromyography, range of motion.FUNCTIONAL MEASURESLBP history; the physical load of profession, physical activity.METHODSPatients were divided in high and low fear of movement groups. Participants walked on a treadmill at four speeds: very slow, slow, preferred and fast. Kinematics of the thorax and the pelvis were recorded, together with the electromyography of five bilateral trunk muscle pairs. Kinematic and electromyography data were analysed in terms of stride-to-stride pattern variability. Factor analysis was applied to assess interdependence of 11 variability measures. To test for differences between groups, a mixed-design multivariate analysis of variance was conducted.RESULTSKinematic variability and variability of muscle activation consistently loaded on different factors and thus represented different underlying variables. No significant Group effects on variability of kinematics and muscle activation were found (Hotelling's Trace F=0.237; 0.396, p=.959; .846, respectively). Speed significantly decreased kinematic variability and increased variability in muscle activation (Hotelling's Trace F=8.363; 4.595, p<.0001; <.0001, respectively). No significant interactions between Group and Speed were found (Hotelling's Trace F=0.204; 0.100, p=.762; .963, respectively).CONCLUSIONSThe results of this study do not support the hypothesis that variability in trunk kinematics and trunk muscle activation during gait in LBP patients are associated with fear of movement.     

Neuromuscular exercises on pain intensity,functional disability,proprioception, and balance of military personnel with chronic low back pain

BackgroundDue to their occupational status, military personnel are a high-risk group for low back pain (LBP).PurposeThe aim of this study was to investigate the effect of neuromuscular exercises on the severity of pain, functional disability, proprioception, and balance in military personnel with LBP.MethodsMilitary personnel with LBP were randomly assigned into two groups: intervention (n=15) and control (n=15). The intervention group performed 60 minutes of neuromuscular exercises three times per week for eight weeks while the control group continued their routine physical activities.ResultsThe mean post-intervention pain intensity, disability, and proprioception error significantly decreased in the intervention group. Whereas their mean post-interventions static and dynamic balance scores significantly increased.ConclusionsThe results indicate eight weeks of neuromuscular exercise decreased pain intensity and improved functional ability, static and dynamic balance, and proprioception among military staff suffering chronic low back pain.     

An educational approach based on a non-injury model compared with individual symptom-based physical training in chronic LBP. A pragmatic, randomised trial with a one-year follow-up

Background  

In the treatment of chronic back pain, cognitive methods are attracting increased attention due to evidence of effectiveness similar to that of traditional therapies. The purpose of this study was to compare the effectiveness of performing a cognitive intervention based on a non-injury model with that of a symptom-based physical training method on the outcomes of low back pain (LBP), activity limitation, LBP attitudes (fear-avoidance beliefs and back beliefs), physical activity levels, sick leave, and quality of life, in chronic LBP patients.     

Assessing a risk tailored intervention to prevent disabling low back pain - protocol of a cluster randomized controlled trial

Background  

Although most patients with low back pain (LBP) recover within a few weeks a significant proportion has recurrent episodes or will develop chronic low back pain. Several mainly psychosocial risk factors for developing chronic LBP have been identified. However, effects of preventive interventions aiming at behavioural risk factors and unfavourable cognitions have yielded inconsistent results. Risk tailored interventions may provide a cost efficient and effective means to take systematic account of the individual risk factors but evidence is lacking.     

One-year prognosis in sick-listed low back pain patients with and without radiculopathy. Prognostic factors influencing pain and disability

Background contextPrevious research has documented various psychosocial risk factors with influence on outcome in low back pain (LBP) patients, but the value of clinical predictors has been less well documented.PurposeTo identify clinical and psychosocial risk factors at baseline influencing disability and pain at 1 year in LBP patients sick-listed 3 to 16 weeks, and to look for differences between nonspecific LBP and radiculopathy.Study designCohort study with 1-year follow-up based on a randomized clinical trial.Outcome measuresDisability and change of disability, pain and change in pain at 1 year.MethodsIn a randomized clinical study evaluating multidisciplinary versus brief intervention, 325 patients were followed for 1 year. At baseline, they completed a questionnaire and went through a clinical low back examination, including measure of forward flexion and side flexion as well as tender point examination, a method to estimate diffuse tenderness. Furthermore, degenerative changes on plain X-rays of the lumbar spine were quantified, and sciatica was investigated by magnetic resonance imaging.ResultsRadiculopathy was verified by magnetic resonance imaging in 111 (34%) patients. At 1 year, questions of disability in daily life activities and pain were answered by 60% and 67%, respectively. The intensity of back+leg pain and disability was closely correlated. Statistically significant predictors for both disability and back+leg pain at 1 year were intensity of back+leg pain, worrying and health anxiety, many tender points, and little or moderate exercise in leisure time. Two additional risk factors were identified in patients with radiculopathy: older age and “drinking alcohol less than once per month.” Furthermore, disability at 1 year was associated with initial disability and compensation claim, and back+leg pain at 1 year was associated with fear avoidance about physical activity and the duration of pain. Change in disability was more closely associated with return to work than change in pain. Disc degeneration was not associated with disability or pain at 1 year. General health was not statistically significantly associated with outcome when adjusted for back+leg pain, disability, and worrying and health anxiety.ConclusionsDisability and pain at 1 year were associated with baseline disability and pain, diffuse tenderness, worrying and health anxiety, compensation claim, fear avoidance, and baseline exercise habits. Only in patients with verified nerve root affection, older age, and restrained alcohol seemed to play a role. The multivariate models were insufficient in predicting disability and pain, partly because disability and pain were also strongly associated with return to work.     

Symptomatology of recurrent low back pain in nursing and administrative professions

The aim of the present study was to explore if (a) recurrent low back pain (LBP) has different symptomatologies in cases from occupations with predominantly sitting postures compared to cases from occupations involving dynamic postures and frequent lifting and (b) if in the two occupational groups, different factors were associated with the presence of recurrent LBP. Hundred and eleven female subjects aged between 45 and 62 years with a long-standing occupation either in administrative or nursing professions, with and without recurrent LBP were examined. An extensive evaluation of six areas of interest (pain and disability, clinical examination, functional tests, MR examination, physical and psychosocial workplace factors) was performed. The variables from the six areas of interest were analyzed for their potential to discriminate between the four groups of subjects (administrative worker and nurses with and without recurrent LBP) by canonical discriminant analysis. As expected, the self-evaluation of physical and psychosocial workplace factors showed significant differences between the two occupational groups, which holds true for cases as well as for controls (P < 0.01). The functional tests revealed a tendency for rather good capacity in nurses with LBP and a decreased capacity in administrative personnel with LBP (P = 0.049). Neither self completed pain and disability questionnaires nor clinical examination or MR imaging revealed any significant difference between LBP cases from sedentary and non-sedentary occupations. When comparing LBP cases and controls within the two occupational groups, the functional tests revealed significant differences (P = 0.0001) yet only in administrative personnel. The clinical examination on the other hand only discriminated between LBP cases and controls in the nurses group (P < 0.0001). Neither MRI imaging nor self reported physical and psychosocial workplace factors discriminated between LBP cases and controls from both occupational groups. Although we used a battery of tests that have broad application in clinical and epidemiological studies of LBP, a clear difference in the pattern of symptoms between LBP cases from nursing and hospital administration personnel could not be ascertained. We conclude that there is no evidence for different mechanisms leading to non-specific, recurrent LBP in the two occupations, and thus no generalizable recommendations for the prevention and therapy of non-specific LBP in the two professions can be given.     

Defining and describing treatment heterogeneity in new-onset idiopathic lower back and extremity pain through reconstruction of longitudinal care sequences

BACKGROUND CONTEXTDespite established guidelines, long-term management of surgically-treated low back pain (LBP) and lower extremity pain (LEP) remains heterogeneous. Understanding care heterogeneity could inform future approaches for standardization of practices.PURPOSETo describe treatment heterogeneity in surgically-managed LBP and LEP.STUDY DESIGN/SETTINGRetrospective study of a nationwide commercial database spanning inpatient and outpatient encounters for enrollees of eligible employer-supplied healthcare plans (2007–2016).PATIENT SAMPLEA population-based sample of opioid-naïve adult patients with newly-diagnosed LBP or LEP were identified. Inclusion required at least 12-months of pre-diagnosis and post-diagnosis continuous follow-up.EXPOSUREIncluded treatments/evaluations include conservative management (chiropractic manipulative therapy, physical therapy, epidural steroid injections), imaging (x-ray, MRI, CT), pharmaceuticals (opioids, benzodiazepines), and spine surgery (decompression, fusion).OUTCOME MEASURESPrimary outcomes-of-interest were 12-month net healthcare expenditures (inpatient and outpatient) and 12-month opioid usage.METHODSAnalyses include interrogation of care sequence heterogeneity and temporal trends in sequence-initiating services. Comparisons were conducted in the framework of sequence-specific treatment sequences, which reflect the personalized order of healthcare services pursued by each patient. Outlier sequences characterized by high opioid use and costs were identified from frequently observed surgical treatment sequences using Mahalanobis distance.RESULTSA total of 2,496,908 opioid-naïve adult patients with newly-diagnosed LBP or LEP were included (29,519 surgical). In the matched setting, increased care sequence heterogeneity was observed in surgical patients (0.51 vs. 0.12 previously-unused interventions/studies pursued per month). Early opioid and MRI use has decreased between 2008 and 2015 but is matched by increases in early benzodiazepine and x-ray use. Outlier sequences, characterized by increased opioid use and costs, were found in 5.8% of surgical patients. Use of imaging prior to conservative management was common in patients pursuing outlier sequences compared to non-outlier sequences (96.5% vs. 63.8%, p<.001). Non-outlier sequences were more frequently characterized by early conservative interventions (31.9% vs. 7.4%, p<.001).CONCLUSIONSSurgically-managed LBP and LEP care sequences demonstrate high heterogeneity despite established practice guidelines. Outlier sequences associated with high opioid usage and costs can be identified and are characterized by increased early imaging and decreased early conservative management. Elements that may portend suboptimal longitudinal management could provide opportunities for standardization of patient care.     

Do rheumatoid arthritis patients have low back pain or radiological lumbar lesions more frequently than the healthy population? – Cross-sectional analysis in a cohort study with age and sex-matched healthy volunteers

BACKGROUND CONTEXTRheumatoid arthritis (RA) can affect the spine; however, the epidemiology of lumbar lesions and/or low back pain (LBP) in RA patients has not been well-studied.PURPOSEThe purpose of this study was to compare the prevalence of lumbar lesions and LBP in RA patients with that in healthy volunteers, and to elucidate the influence of RA on lumbar disease.STUDY DESIGNCross-sectional analysis in a cohort study with age- and sex-matched healthy volunteers.PATIENT SAMPLEThis study included 185 patients with RA and 188 gender/age-matched healthy volunteers without RA.OUTCOME MEASURESLumbar spondylolisthesis and prevalent vertebral fractures were evaluated using plain lateral X-ray images. Thoraco-lumbar scoliosis was evaluated using dual-energy X-ray absorptiometric images. LBP was assessed using the visual analogue scale (VAS) and Rolland-Morris disability questionnaire (RDQ).METHODSThe prevalence of radiological lumbar lesion and LBP was compared between the RA and control groups. In the RA group, factors associated with lumbar lesion and LBP were analyzed using a multiple logistic regression model.RESULTSThe prevalence rates of spondylolisthesis and prevalent vertebral fracture were significantly higher in the RA group than in the control group; the prevalence of thoraco-lumbar scoliosis tended to be higher in the RA group. There was no significant difference in the average LBP-VAS between the groups. However, the percentage of analgesic drug use was significantly higher, and RDQ scores tended to be worse in the RA group than the control group. Multivariate analysis revealed that age and disease activity score were both related to LBP in the RA group.CONCLUSIONSRA patients are more likely to have radiological lumbar lesions. LBP in RA patients is well controlled, similar to the level in the healthy population; however, disease activity was related to LBP in RA patients. These results suggest that disease control is important for lumbar care in RA patients.     

Dynamic changes of elasticity, cross-sectional area, and fat infiltration of multifidus at different postures in men with chronic low back pain

Background contextMultifidus cross-sectional area was often measured in chronic low back pain (LBP) patients to estimate the muscle activity for spinal stability. However, such estimation may be inadequate as the contribution of muscle elasticity in muscle activity is ignored. In vivo quantitative data on multifidus elasticity is therefore important for the study of muscle contractile function in response to motor control for spinal stability in chronic LBP patients.PurposeThe purpose of this study was to quantify the elasticity, cross-sectional area, and fat area of the multifidus for the contractile function and the distribution of deformable muscle tissue and nondeformable fat tissue at different postures in patients with and without chronic LBP.Study design/settingThis is a prospective study. Force-deformation data of the multifidus were acquired using ultrasound elastography. The anatomical changes of the multifidus were measured on the cross-sectional images of the multifidus acquired using B-mode ultrasound imaging.Patient sampleThe sample comprised 12 adult male patients with chronic LBP and 12 asymptomatic male controls.Outcome measuresThe outcome measure was the elasticity of the multifidus at the L4 level for the assessment of muscle contractile function when patients were in the prone, upright, and 25° and 45° forward stooping positions. The cross-sectional area and fat area were also measured on the B-mode ultrasound images of the multifidus acquired at the same vertebral level and the postures.MethodsWith the patients in each of the prone, upright, and 25° and 45° forward stooping positions, ultrasound elastography and B-mode ultrasound imaging were performed on the left and right multifidus at the L4 level. The elasticity of multifidus indicated by the effective Young’s modulus was derived from the force-deformation data acquired using ultrasound elastography. The cross-sectional area and fat area were assessed on the B-mode ultrasound images. The effective Young’s modulus, cross-sectional area, and fat area were analyzed with multivariate general linear model analysis to investigate the possible effects of LBP and posture.ResultsThere was an increasing stiffness of multifidus demonstrated by increasing effective Young’s modulus from the prone to upright position and 25° and 45° forward stooping positions. Differences in multifidus stiffness between chronic LBP patients and asymptomatic controls were shown in the upright and 25° and 45° forward stooping positions but not in the prone position. The cross-sectional area of the multifidus increased from the prone position to the greatest value in the upright position and decreased in 25° and 45° forward stooping positions. Smaller multifidus cross-sectional area was demonstrated in chronic LBP patients than that in controls at all postures. No effect of posture on fat area within the multifidus was shown although the fat area within the multifidus was larger in chronic LBP patients.ConclusionsDifferent, changing patterns of elasticity and cross-sectional area were identified in the multifidus in relation to posture. Increased stiffness of multifidus in response to the physiologic range of static loads and smaller cross-sectional area was characterized in the chronic LBP condition for spinal stability. Ultrasound elastography offers in vivo assessment of muscle contractile function of deep trunk muscles, which benefits the future investigation of the neuromuscular regulating mechanism in LBP. It can also be applied to refine the palpatory skill for the physical assessment in sports training and physical therapy.     

Spinal extra-dural metastasis from Merkel cell carcinoma: a rare cause of paraplegia

Recurrent low back pain (LBP) is a common pain condition in elderly workers in a variety of occupations, but little is known about its origin and the mechanisms leading to an often disabling sensation of pain that may be persistent or intermittent. In the present study we evaluated the pressure pain thresholds (PPTs) in subjects suffering from recurrent LBP, as well as in healthy controls, to investigate if recurrent LBP is associated with an increased sensitivity of the muscular and ligamentous structures located on the lower back. One hundred and six female workers, aged between 45 and 62 years and working either in administrative or nursing professions were examined. The subjects were classified into LBP cases and controls based on the Nordic questionnaire. Subjects indicating 8-30 or more days with LBP during the past 12 months were graded as cases. PPTs were measured on 12 points (six on each side of the body) expected to be relevant for LBP (paravertebral muscles, musculus quadratus lumborum, os ilium, iliolumbar ligament, musculus piriformis and greater trochanter), as well as on a reference point (middle of the forehead) using a digital dolorimeter. The PPTs on all points on the lower back highly correlated with each other and a high internal consistency was found with a Cronbach alpha coefficient > 0.95. There was a moderate and significant correlation of the PPT on the forehead with the PPT on the lower back with correlation coefficients ranging from 0.36 to 0.49. In LBP cases from administrative professions, the PPT on the forehead was significantly decreased (P < 0.05). The PPT on the lower back did not significantly differ between the four groups studied, namely nurses and administrative workers with and without recurrent LBP. These results give evidence that recurrent LBP is not associated with an altered sensitivity of the muscular and myofascial tissues in the lumbar region. Furthermore, they raise questions about the value of reference point measurements in recurrent LBP.     

Spine loading in patients with low back pain during asymmetric lifting exertions

Background contextRecurrent low back pain (LBP) is a common and costly problem that might be related to increased spine loads in those with LBP. However, we know little about how the spine is loaded when those with LBP perform lifting exertions.PurposeDocument spine loading patterns of patients with LBP performing symmetric and asymmetric lifting exertions compared with asymptomatic individuals performing the same tasks.Study designSpine loadings during lifting exertions that varied in asymmetric origin as well as horizontal and vertical distance from the spine were compared between asymptomatic subjects and patients with LBP.MethodsSixty-two patients with LBP and 61 asymptomatic individuals performed a variety of lifting exertions that varied in lift origin horizontal and vertical position (region), lift asymmetry position and weight lifted. An electromyography-assisted model was used to evaluate spine loading in each subject during the lifting exertions. Differences in spine loading between the LBP and asymptomatic subjects were noted as a function of the experimental variables.ResultsPatients with LBP experienced greater spine compression and shear forces when performing lifting tasks compared with asymptomatic individuals. The least taxing conditions resulted in some of the greatest differences between LBP and asymptomatic individuals.ConclusionsGreater levels of antagonistic muscle coactivation resulted in increases in spine loading for patients with LBP. Specific lifting conditions that tend to exacerbate loading can be identified by means of physical workplace requirements. These findings may impact acceptable return-to-work conditions for those with LBP.     

Design considerations in a clinical trial of a cognitive behavioural intervention for the management of low back pain in primary care: Back Skills Training Trial

Background  

Low back pain (LBP) is a major public health problem. Risk factors for the development and persistence of LBP include physical and psychological factors. However, most research activity has focused on physical solutions including manipulation, exercise training and activity promotion.     

Factors associated with fear-avoidance beliefs about low back pain

BackgroundLow back pain (LBP) is a common major health problem. Fear-avoidance beliefs are thought to be an important risk factor for chronic LBP. This study investigated factors associated with the Fear-Avoidance Beliefs Questionnaire (FABQ) scores of Japanese adults who experienced LBP. We focused on the association of FABQ scores with medical advice to rest and the experience of seeing family members and/or significant others with disabling LBP.MethodsIn February 2011, 1,063,083 adults aged 20–79 years who had registered as internet-based research volunteers were randomly selected and invited to participate in a questionnaire survey. The data from 52,650 respondents who had experienced LBP were analyzed. Multiple linear regression analysis was used to examine the association between FABQ physical activity scores and the advice for respondents with LBP to rest, the experience of seeing others with disabling LBP, and other personal and LBP factors.ResultsAfter controlling for age, sex, and lifetime and current LBP disability grades, the experience of seeing others with disabling LBP (regression coefficient β = 0.94), rest advice (β = 0.91), history of chronic LBP (β = 0.78), radiating pain below the knee (β = 0.44), and workers’ compensation (β = 0.51) were associated with higher FABQ physical activity scores. Conversely, regular exercise (β = ?0.89) and LBP attributed to sports (β = ?0.76) were associated with lower FABQ physical activity scores.ConclusionThe association between rest advice and higher fear-avoidance beliefs supports the recent treatment guidelines that emphasize continuation of daily activities.Study design: cross-sectional study.