Previous Low Back Pain Research Articles

Prevalence and Biopsychosocial Factors Associated With a Current Episode of Low Back Pain Among Adults With a Previous History of Low Back Pain: A Cross-sectional Study of Market Traders in an African Population

Low back pain (LBP) is the leading cause of years lived with disability globally, with Nigeria having one of the greatest burdens. A current episode of LBP is important in Nigeria, but the associated factors are unknown. This cross-sectional study investigated the prevalence, biomechanical, and psychosocial factors associated with a current episode of LBP among 700 adult market traders with previous LBP in an urban Nigerian population. Descriptive, bivariate, and multivariate analyses were conducted. The prevalence of a current episode of LBP was 76.4%. Factors associated with an increased risk of a current episode of LBP in a decreasing order of importance were exposure to biomechanical factors (aggregate [total] score) (odds ratio [OR] = 1.535; 95% confidence interval [CI] = 1.398–1.685); anxiety (OR = 1.182; 95% CI = 1.089–1.282); fear-avoidance beliefs (physical activity) (OR = 1.139; 95% CI = 1.029–1.261); fear-avoidance beliefs (work) (OR = 1.105; 95% CI = 1.047–1.165); while factors associated with a reduced risk of a current episode of LBP were ability to take breaks in the job in addition to scheduled breaks (OR = .430; 95% CI = .240–.773) and ability to control the order and pace of tasks (OR = .477; 95% CI = .236–.965). Occupational biomechanical and psychosocial factors were associated with a current episode of LBP in logistic regression models explaining 52.7% and 73.1% of the variation in a current episode of LBP. Occupational biomechanical factors, particularly handling large and bulky objects at arm’s length and kneeling and squatting, produced the greatest risk of a current episode of LBP. PerspectiveOccupational biomechanical factors, occupational psychosocial factors, and personal psychosocial factors such as anxiety and fear-avoidance beliefs are associated with a current episode of LBP in Nigeria. Pragmatic public health and occupational health initiatives that modify exposure to these factors may be required in Nigeria.

Is low back pain a risk/prognostic factor for the development and/or progression of temporomandibular disorders? A systematic review with meta-analysis.

To evaluate the association between low back pain (LBP) and painful temporomandibular disorders (TMDs). Systematic review of observational studies. Searches were conducted using OVID MEDLINE, CINHAL, Web of Science and PUBMED databases up to 21 October 2022. Qualitative and quantitative analyses were performed. Risk of bias (RoB) was assessed using the Quality in Prognosis Studies tool (QUIPS). Eight studies were included in the present review with meta-analysis. The first onset of TMDs was more likely in patients with previous chronic LBP (hazard ratio (HR) 1.53 [95% confidence interval (CI): 1.28; 1.83, p < .00001]). In addition, patients with chronic LBP had 3.25 times the odds (OR) [95% CI: 1.94; 5.43, p < .00001] of having chronic TMDs than those who did not have chronic LBP. In addition, the higher the exposure to chronic LBP, the higher the risk of developing a first onset of TMDs. Chronic LBP can be considered a risk/contributing factor for painful TMDs. Although there is a high certainty in the evidence linking chronic LBP with the risk of a first onset of TMDs, there are insufficient studies to draw definitive conclusions. Furthermore, while an association between chronic LBP and chronic TMDs and a dose-effect was observed between these two conditions, a limited number of studies and evidence exist to support these findings. Future studies are needed to increase the body of evidence.

PREVALENCE OF LOW BACK PAIN DURING PREGNANCY: A CROSS-SECTIONAL STUDY IN A TERTIARY CARE HOSPITAL.

Objective:To assess the severity of low back pain (LBP) during pregnancy including prevalence,risk factors,impact on daily life and health management in a tertiary care hospital in Jammu. Methods: An anonymous, 30-question questionnaire was administered to pregnant women admitted to a tertiary care hospital and attending the OPD.A total of 500 surveys were returned between April 2022 and September 2022. Results: 325 (65%) respondents reported experiencing LBP during the current pregnancy. Gestational age did not affect incidence. Back pain during current pregnancy was predicted by age (younger women were more likely to experience it; LBP without pregnancy, during menstruation and during previous pregnancy. Most respondents reported that LBP during pregnancy caused sleep disturbances (52).%) and worsened daily life (58%) Average pain was moderate Almost 32% of respondents stopped at least one daily activity because of pain and reported that the pain also prevented them from performing other routine activities. Only 40% of respondents who experienced LBP during pregnancy reported the problem to their prenatal care providers,and only 22% of prenatal care providers recommended treatment. Conclusion: Our study showed that LBP during menstruation predicts a high risk of LBP in the current pregnancy. The study showed that LBP during menstruation and previous LBP can be useful tests to rule out and resolve LBP during pregnancy.

Reliability and validity of subjective radiologist reporting of temporal changes in lumbar spine MRI findings.

The importance of lumbar findings on magnetic resonance imaging (MRI) remains controversial. Changes in lumbar MRI findings over time may provide important insights into the causes of low back pain. However, the reliability and validity of temporal changes are unknown. To (1) investigate the interrater reliability of subjective radiologist reporting of temporal changes in lumbar spine MRI findings and (2) determine how commonly temporal changes are reported when two scans are conducted 30 minutes apart (considered false positives). Cross-sectional study. Radiology clinic. Forty volunteers (mean age 40; 53% female) with current (n=31) or previous (n=9) low back pain underwent initial lumbar MRI on a single 3T scanner. Participants then lay on a bed for 30 minutes before undergoing an identical MRI. In addition, we purposely selected five participants from a previous study with repeat lumbar MRI scans where temporal changes were reported in at least one MRI finding (1-12 weeks after initial scan) and another five participants where no temporal change was reported. The 10 participants were included in analyses for aim 1 only. Not applicable. Two blinded radiologists reported on temporal changes between the baseline and repeat scan for 12 different MRI findings (eg, disk herniation, annular fissure) at five levels. The interrater reliability of subjective reporting of temporal changes was poor for all MRI findings based on Kappa values (≤ 0.24), but agreement was relatively high (≥ 90.8%). This is explained by the low prevalence of temporal changes as demonstrated by high values for Prevalence and Bias Adjusted Kappa (≥ 0.82). "False positive" temporal changes were reported by at least one radiologist for most MRI findings, but the rate was generally low. Caution is required when interpreting temporal changes in lumbar MRI findings owing to low reliability and some false positive reporting.

Relationship between systemic inflammation and recovery over 12 months after an acute episode of low back pain

BACKGROUND CONTEXTIndividual characteristics can influence outcomes after injury. Our previous work in individuals with early-acute low back pain (LBP) identified subgroups (clusters) with specific biopsychosocial features that recovered poorly or well by 6 months. PURPOSEThis study extends on that work by revealing the short- and long-term trajectories of recovery and systemic inflammation of these participant clusters: (1) “inflammatory & poor sleep” (Cluster 1), “high TNF & depression” (Cluster 2), “high pain & high pain-related fear” (Cluster 3), and “low pain & low pain-related fear” (Cluster 4). STUDY DESIGN/SETTINGLongitudinal cohort study. PATIENT SAMPLEEighty-three individuals within 2 weeks of an acute episode of LBP – grouped into their a priori-defined cluster. OUTCOME MEASURESGeneral participant characteristics (sex, age, body mass index, smoking history, previous LBP history); self-reported LBP (0–10 numerical rating scale, LBP-related disability (Roland-Morris Disability Questionnaire), depression (Center for Epidemiological Studies Depression Scale, pain catastrophizing (Pain Catastrophizing Scale), fear avoidance (Fear Avoidance Beliefs Questionnaire), pain self-efficacy (Pain Self-Efficacy Questionnaire), and sleep (Pittsburgh Sleep Quality Index); systemic inflammatory biomarkers (C-reactive protein [CRP], interleukin-6 [IL-6], interleukin-1β, tumor necrosis factor [TNF]). METHODSParticipants provided blood for the measurement of CRP/cytokines, and completed questionnaires related to their pain/disability, psychological and sleep status. Blood measures were repeated 3-monthly for 9 months, and pain/disability were self-reported fortnightly for 12 months. Recovery (change in pain) and CRP/cytokines were longitudinally compared between clusters using mixed-models. Associations between baseline factors and follow-up CRP/cytokines levels were assessed with multiple regression. RESULTSClusters 1 and 2 were associated, but oppositely, with recovery over the 12-months. Cluster 1 reported most recovery at every 3-monthly interval, whereas Cluster 2 reported least recovery. Cluster 1 had elevated CRP (and IL-6) at baseline that continued to decrease from 3 to 9 months. TNF was elevated early and persistently in Cluster 2. Baseline factors other than inflammation generally failed to predict follow-up inflammation. CONCLUSIONSFindings support the early role of CRP (and perhaps IL-6) in control of inflammation and recovery, and a pathological role of persistent TNF overexpression, which may be perpetuated by depressive-like behaviors.

Relationship between Low Back Pain and Stress Urinary Incontinance in Middle - Aged Women

Abstract Background: Low back pain (LBP) and stress urinary incontinence (SUI) are common problems in women, there are many factors that associated with the development of LBP, but there are a limited research that evaluate the relationship between LBP and SUI. Aim of Study: To determine the relationship between stress urinary Incomitance and low back pain in middle-aged women. Material and Methods: One hundred multipara women participated in this study. 50 women complained from stress urinary incontinence (diagnosed by physician) and 50 women were free from stress urinary incontinence (diagnosed by physician). They were selected from Al-Hussein University Hospital in Cairo, Al-Azhar University from November 2020 to March 2021. Their ages were ranged from 35 to 45 years old. Their body mass index was not exceeding 30kg/m2. They were multipara women. Patients with corrected SUI, previous low back surgery, spondylolisthesis and chronic low back pain were excluded from the study. They were divided ran-domly into two equal groups (AB p-value=0.151. While in group (B). There was a statistical significant negative correlation between oswestry low back pain disability questionnaire (ODI) and pelvic floor muscle strength (PFMS) (r=–0.281; p-value=0.048) and in all studied cases (group A + B). There was a statistical signif-icant negative correlation between oswestry low back pain disability questionnaire (ODI) and pelvic floor muscle strength (PFMS) (r=–0.419; p-value=0.001). Conclusion: Accordingly, it can be concluded that there is a positive relationship between low back pain and stress urinary incontinence and presence of stress urinary inconti-nence is predisposing factor for low back pain.

Prevalence and Factors Associated with Pelvic Girdle Pain During Pregnancy in Australian Women: A Cross-Sectional Study.

Cross-sectional study conducted between December 2017 and October 2019. To determine the prevalence and risk factors associated with pregnancy-related pelvic girdle pain (PPGP) in Australia. PPGP is a common condition worldwide yet the prevalence and associated risk factors are not known in Australia. A random sample of pregnant women (N = 780) of (mean [SD]) 31 (5) years of age between 14 and 38 weeks gestation attending ante-natal care in a tertiary referral hospital in Sydney, Australia was conducted. The main outcome measure was point-prevalence of PPGP as classified by recommended guidelines including a physical examination. A number of potential risk factors, including socio-demographic characteristics, country of birth, ethnicity, history of low back pain (LBP) and PPGP, family history of PPGP, occupational factors, and physical activity were investigated with logistic regression. The point-prevalence of PPGP in a random sample of 780 Australian women was 44% with the odds of having PPGP increasing with each additional week of gestation (odds ratio [OR]) (OR 1.02). Increasing parity (P = 0.03, OR 1.15), country of birth (P = 0.03), and greater duration of time spent standing (P = 0.009, OR 1.06) were associated with PPGP. The strongest predictors of PPGP were previous LBP and/or PPGP both pregnancy (P < 0.001, OR 4.35) and not pregnancy related (P < 0.001, OR 2.24), and a family history of PPGP (P < 0.001, OR 3.76). The prevalence of PPGP in Australian women was high with almost half the sample classified with PPGP, matching data reported worldwide. The identified risk factors associated with PPGP can be included in routine ante-natal care to screen women and identify those at risk of this common and disabling condition.Level of Evidence: 1.

A 5-year Longitudinal Study of Low Back Pain in Survivors of the Great East Japan Earthquake.

A longitudinal panel study. The aim of this study was to examine the occurrence of low back pain (LBP), especially the association of previous LBP with further episodes of LBP, in survivors of the Great East Japan Earthquake (GEJE) during the course of 5 years. LBP is common among survivors of natural disasters, but its long-term course is not clear. A 5-year longitudinal study was conducted among survivors of the GEJE (n = 1821). The presence of LBP was assessed using a self-reported questionnaire at 2, 4, and 7 years after the disaster (termed the first, second, and third time points, respectively). Multiple logistic regression analysis was performed to assess a potential association between LBP at the first and second time points with LBP at the third time point, and the odds ratios (ORs) and 95% confidence intervals (CI) were calculated. The prevalence of LBP was 25.3%, 27.3%, and 27.2% at the first, second, and third time points, respectively. The occurrence of LBP at the first time point was significantly associated with LBP at the third time point, and the adjusted odds ratio (OR) (95% confidence interval [CI]) was 5.47 (4.28-6.98). Furthermore, LBP at the first and second time points was significantly associated with LBP at the third time point. Compared to no LBP at the first and second time points, the adjusted OR (95% CIs) for LBP at the third time point was 4.12 (3.14-5.41) in the case of LBP at either of the first or second time points and 10.73 (7.80-14.76) for LBP at both time points (P for trend < 0.001). Previous LBP was associated with LBP 5 years later among survivors of the GEJE. Furthermore, the effect on subsequent LBP was stronger with a higher frequency of previous LBP episodes.Level of Evidence: 3.

Complex sociodemographic inequalities in consultations for low back pain: lessons from multilevel intersectional analysis.

Sociodemographic inequalities in the occurrence of low back pain (LBP) are well-studied. This study aimed to examine complex sociodemographic inequalities in the risk of LBP consultation in the population from a socioeconomical intersectional perspective. Using register data, we identified 458,852 individuals aged 35 to 75 years residing in Skåne in 2013, with no previous LBP consultation since 2006. We created 108 strata using categories of age, sex, education, income, and nativity. With individuals nested within strata, we modelled the absolute risk of LBP consultation during 2014 in a series of multilevel logistic regression models. We quantified discriminatory accuracy (DA) of these variables by computing the variance partition coefficient and area under the receiver operating characteristic curve (AUC). We identified 13,657 (3.0%) people with an LBP consultation. The absolute risk ranged from 2.1% (95% credible interval: 1.9%-2.3%) among young native men with high education and high income to 4.8% (4.3%-5.5%) among young foreign-born women with medium education and low income (2.3-fold relative difference). Discriminatory accuracy of intersectional strata was very low (variance partition coefficient 1.1% (0.7-1.6); and AUC 0.56 [0.55-0.56]). Sex (35.6%) and nativity (19.2%) had the largest contributions in explaining the initially small between-strata variation in risk of LBP. The low DA of the intersectional strata indicates the existence of limited intersectional inequalities in LBP consultation. Therefore, interventions to reduce LBP risk should be universal rather than targeted to specific socioeconomic groups with a higher average risk. Before planning targeted intervention, other risk factors with higher DA need to be identified.

A prospective study of low back pain in a general population. I. Occurrence, recurrence and aetiology

A general population of 928 men and women aged 30, 40, 50, and 60 years underwent a lower back examination as part of a general health survey. A 12 month follow-up questionnaire was completed by 99% of them. At the end of the follow-up year, the life time prevalence rates for low back pain (LBP) were 68-70% for men and rose with increasing age from 62% to 81% among women. The one year incidence of first attacks of LBP was 11% among the 30-year-olds and decreased in the older age-groups. Recurrences of LBP in the follow-up year were more frequent among those who had more recently and frequently experienced LBP before. Among those who had experienced LBP on some occasion, 23-31% had such symptoms daily or at least once a week. Heavy lifting, twisting and trauma were the most commonly stated causes of LBP, which 52-60% of the participants claimed to be work-related. A gradual onset and exacerbation of the LBP were of some prognostic value in the follow-up year, while the alleged cause of previous LBP was not.

Pregnancy in Patients With Low Back Pain

Pregnancy-related lumbopelvic pain has been a serious and common problem since ancient time. The present review article focuses on terminology, types, clinical presentation, and management of these problems. There are two entities regarding pregnancy-related lumbopelvic pain: pelvic girdle pain (PGP), and pregnancy-related low back pain (LBP). There are multiple mechanisms behind these disabilities. Age, multiparty, heavy weight lifting, hard physical activity, previous LBP, and low education increase the prevalence. About one-half of women with pregnancy-related lumbopelvic pain have PGP, one-third LBP, and one-sixth have both conditions. Overall, the literature reveals that PGP deserves serious attention from the clinical and economic standpoints.

What decreases low back pain? A qualitative study of patient perspectives.

Background and aims This study aimed to determine, from the perspective of individuals living with the condition, what decreases their low back pain (LBP). LBP affects most people at some point during their life. The condition has a meaningful effect on people's lives including pain, reduced physical and social function, mood fluctuations, and a reduced ability to work. Despite a considerable amount of research on the topic, few strategies to reduce LBP are considered successful, and there has been little investigation into what individuals with the condition believe reduce it. This study aimed to address this gap in the literature by investigating what individuals with the condition believe reduces their LBP. Methods We employed a descriptive qualitative design using a custom-built online survey. Participants were 130 adults in Australia who self-identified as having current or having had previous LBP with or without co-morbidities. Data from the survey responses were analysed using content analysis to determine which management approaches participants considered to be effective in reducing their LBP. Results Participants most commonly said that they believed their LBP was reduced by: heat/cold (86, 66%), medication (84, 64.1%), and rest (78, 60%). Next most common was activity/exercise (73, 55.7%). Other factors such as consulting a health professional (52, 39.7%), stretching/therapeutic exercise (50, 38.1%), resting from aggravating activities (45, 34.3%), and psychological changes (41, 31.3%) were mentioned, but considerably less often. Conclusions Current literature points to the inefficacy of many of the factors participants reported as helping to reduce the effects of their condition, including the treatments that were most commonly listed by the participants in this study, namely: heat/cold, medication and rest. A possible cause of this discrepancy might be that individuals with LBP consider temporary relief (on a scale of hours) to be an acceptable outcome, whereas clinical trials tend to consider efficacy by long term outcomes (on a scale of weeks, months or years). Implications There are several implications of this research. From one perspective, there is the implication that public education about efficacious treatments may need to be enhanced as there is a discrepancy between research findings and the perspectives of individuals living with LBP. On the other hand, these findings also suggest that it is timely to re-examine the focus of LBP research to consider outcomes that are valuable to people living with the condition, which this study implies should include short term or temporary effects. The findings may also help clinicians tailor management to suit the individual patients by increasing the awareness that patient and research perspectives may at times diverge.

Landing Stiffness Between Individuals With and Without a History of Low Back Pain.

Reduced spinal stabilization, delayed onset of muscle activation, and increased knee joint stiffness have been reported in individuals with a history of low back pain (LBP). Biomechanical adaptations resulting from LBP may increase the risk for future injury due to suboptimal loading of the lower-extremity or lumbar spine. Assessing landing mechanics in these individuals could help identify which structures might be susceptible to future injury. To compare vertical and joint stiffness of the lower-extremity and lumbar spine between individuals with and without a previous history of LBP. Cross-sectional study. Research laboratory. There were 45 participants (24 without a previous history of LBP-age 23 [8]y, height 169.0 [8.5]cm, mass 69.8 [13.8]kg; 21 with a previous history of LBP-age 25[9]y, height 170.0 [8.0]cm, mass 70.2 [11.8]kg). Single-limb landing trials on the dominant and nondominant limb from a 30-cm box. Vertical stiffness and joint stiffness of the ankle, knee, hip, and lumbar spine. Individuals with a previous history of LBP had lower vertical stiffness (P = .04), but not joint stiffness measures compared with those without a previous history of LBP (P > .05). Overall females had lower vertical (P = .01), ankle (P = .02), and hip stiffness (P = .04) compared with males among all participants. Males with a previous history of LBP had lower vertical stiffness compared with males without a previous history LBP (P = .01). Among all individuals without a previous history of LBP, females had lower vertical (P < .01) and ankle stiffness measures (P = .04) compared with males. Landing stiffness may differ among males and females and a previous history of LBP. Comparisons between individuals with and without previous LBP should be considered when assessing landing strategies, and future research should focus on how LBP impacts landing mechanics.

Prognostic factors for pregnancy-related pelvic girdle pain, a systematic review

BackgroundPregnancy-related Pelvic Girdle Pain (PPGP) is a very common complaint. Although many women recover after a birth, about a third continue to have symptoms three months postpartum and 8.5% of women still have persistent symptoms two years afterwards. Knowledge of prognostic factors may help understand the course of PPGP and inform management. ObjectivesTo determine the prognostic factors for PPGP by systematically reviewing the literature. DesignSystematic review. MethodsWe searched PubMed, Embase, CINAHL, PsycINFO, MIDIRS, and ClinicalTrial.gov (15 April 2017) with no filters. Only studies reported in English were included. Two review authors independently selected studies. Any factors that might affect the course of PPGP up to one year postpartum were of interest. We excluded interventions and diagnostic studies. We conducted double independent data extraction, risk of bias and quality of evidence (GRADE) assessment. FindingsWe identified 4374 citations of which three studies were included in our analysis. Previous low back pain, pain in three to four pelvic locations, and being overweight/obese made recovery 12 weeks postpartum less likely. Six months postpartum, Pelvic Girdle Syndrome (PGS) was more likely to persist in women who used crutches or had severe pain in three pelvic locations during pregnancy, had other pain conditions, a younger age of menarche, previous low back pain or a high co-morbidity index, were obese, or experienced emotional distress during pregnancy. For women who used crutches during pregnancy, an instrumental birth or caesarean section was associated with persistent PGS. However, the quality of evidence (GRADE) was low to very low for all factors, hence, findings are uncertain. Key conclusionsThe limited number of studies and lack of replication prevents us from drawing definitive conclusions. Implications for practicePotentially modifiable factors during pregnancy seem to impact the prognosis of PPGP postpartum.

Effectiveness of diathermy in patients with low back and pelvic pain referred to lower limb: A pilot study

Objectives: Low Back and pelvic pain is a major problem and a common cause of disability and health care utilization. To evaluate diathermy efficacy for low back and pelvic pain treatment.Methods: Reports of 20 multifidus in subjects with a previous low back and pelvic pain diagnosis. A randomized trial blinded with two randomized groups, group A diathermy, group B sham diathermy to check efficacy of diathermy.Results: Diathermy group don´t show significate differences versus sham group due to be apply as an isolated technique but this technique rarely is reported in this way and is frequently associated to perturbational training or a kinesiotherapy program during his activation. A better correlation was achieved by diathermy in Tensomiography values.Conslusions: Further studies are necessary to improve knowledge about physical effects of diathermy due to this technique is frequently associated with a kinesiotherapy program to get better results in patients with prevalent illness as lumbar and pelvic pain referred to lower limb.

Are people with chronic low back pain meeting the physical activity guidelines? A co-twin control study

BackgroundDespite a large amount of research investigating physical activity (PA) levels in people with chronic low back pain (LBP), no study has investigated whether people with chronic LBP are meeting the World Health Organization (WHO) PA guidelines. Furthermore, with genetics and the early shared environment substantially influencing the presence of LBP and PA engagement, these factors could confound the association between LBP and PA and need to be controlled for. PurposeThis study aimed to investigate the association between chronic LBP and meeting the PA guidelines, while controlling for the effects of genetics and early shared environment. DesignThis is a cross-sectional co-twin control study. Patient SampleA cross-sectional analysis was performed on 1,588 twins from the Murcia Twin Registry in Spain with available data on LBP and PA from the 2013 data collection wave. Outcome MeasuresThe exposure and outcome variables in our study were self-reported. Twins reporting a history of chronic LBP were asked follow-up questions to inform on the presence of recent LBP (within the past 4 weeks), previous LBP (no pain within the past 4 weeks), and persistent LBP (no pain-free month in the last 6 months). These were our exposure variables. Our outcome variable was meeting the WHO PA guidelines, which involved at least 75 minutes of vigorous-intensity PA, or at least 150 minutes of moderate-intensity PA per week. MethodsTo investigate the association between chronic LBP and meeting the PA guidelines, we first performed a multivariate logistic regression on the total sample of twins. Co-variables entered the model if the univariate association between the co-variable, and both the exposure and the outcome reached a significance of p<.2. Second, to adjust for the influence of genetics and early shared environment, we performed a conditional multivariate logistic regression on complete twin pairs discordant for LBP. The Murcia Twin Registry is supported by Fundación Séneca, Regional Agency for Science and Technology, Murcia, Spain (08633/PHCS/08 and 15302/PHCS/10) and the Ministry of Science and Innovation, Spain (PSI11560-2009). Funding for this project has also been received from Fundación MAPFRE (2012). The authors declare that there are no conflicts of interest. ResultsThere was a significant inverse association between recent LBP and meeting the PA guidelines (odds ratio [OR]=0.71, p=.034). When controlling for genetics and early shared environment, this association disappeared. There was no association between previous (OR=0.95, p=.779) or persistent LBP (OR=0.78, p=.192) and meeting the PA guidelines. ConclusionTwins with recent LBP are less likely to meet the PA guidelines than those with no history of chronic LBP, highlighting the importance of incorporating PA promotion in the treatment of these individuals. Genetics and early shared environment appear to be confounding the association between LBP and PA, although this needs to be further tested in larger twin samples.

The relationship between findings on magnetic resonance imaging and previous history of low back pain.

The objective of this study was to evaluate the relationship between magnetic resonance imaging (MRI) findings and previous low back pain (LBP) in participants without current LBP. Current LBP was defined as LBP during the past month. Previous LBP was defined as a history of medical consultation for LBP. Ninety-one participants without current LBP were included. Sagittal T2-weighted MRI was used to assess the intervertebral space from T12/L1 to L5/S1. These images were classified into five grades based on the Pfirrmann grading system. Furthermore, we evaluated the presence of disk bulging, high-intensity zone, and spondylolisthesis. We compared the MRI findings between groups with (27 participants) and without (64 participants) previous LBP without current LBP. Intraobserver and interobserver kappa values were evaluated. Participants had an average age of 34.9 years; 47 were female and 44 were male; and their average body mass index was 21.8 kg/m2. Compared to the group of participants without previous LBP, the group of participants with previous LBP had a significantly higher incidence of disk degeneration such as a Pfirrmann grade ≥3, disk bulging, and high-intensity zone in the analyses adjusted by age and sex. There were no significant differences in spondylolisthesis between the groups. An odds ratio of >10 was only found for Pfirrmann grade ≥3, ie, a Pfirrmann grade ≥3 was strongly associated with a history of previous LBP in participants without current LBP.

Identification of subgroups of inflammatory and degenerative MRI findings in the spine and sacroiliac joints: a latent class analysis of 1037 patients with persistent low back pain.

BackgroundThe aim of this study was to investigate subgroups of magnetic resonance imaging (MRI) findings for the spine and sacroiliac joints (SIJs) using latent class analysis (LCA), and to investigate whether these subgroups differ in their demographic and clinical characteristics.MethodsThe sample included 1037 patients aged 18–40 years with persistent low back pain (LBP). LCA was applied to MRI findings of the spine and SIJs. The resulting subgroups were tested for differences in self-reported demographic and clinical characteristics.ResultsA five-class model was identified: Subgroup 1, ‘No or few findings’ (n = 116); Subgroup 2, ‘Mild spinal degeneration’ (n = 540); Subgroup 3, ‘Moderate to severe spinal degeneration’ (n = 229); Subgroup 4, ‘Moderate to severe spinal degeneration with mild SIJ findings’ (n = 68); and Subgroup 5, ‘Mild spinal degeneration with moderate to severe SIJ findings’ (n = 84). The two SIJ subgroups (Subgroups 4 and 5) had a higher median activity limitation score (Roland Morris Disability Questionnaire calculated as a proportional score: 65 (IQR 48–78)/65 (48–78)) compared with Subgroups 1–3 (48 (35–74)/57 (39–74)/57 (39–74)), a higher prevalence of women (68 % (95 % CI 56–79)/68 % (58–78)) compared with Subgroups 2 and 3 (51 % (47–55)/40 % (33–46)), a higher prevalence of being overweight (67 % (95 % CI 55–79)/53 % (41–65)) compared with Subgroup 1 (36 % (26–46)) and a higher prevalence of previous LBP episodes (yes/no: 81 % (95 % CI 71–91)/79 % (70–89)) compared with Subgroup 1 (58 % (48–67)). Subgroup 5 was younger than Subgroup 4 (median age 29 years (IQR 25–33) versus 34 years (30–37)) and had a higher prevalence of HLA-B27 (40 % (95 % CI 29–50)) compared with the other subgroups (Subgroups 1–4: 12 % (6–18)/7 % (5–10)/6 % (3–9)/12 % (4–20)). Across the subgroups with predominantly spinal findings (Subgroups 1–3), median age, prevalence of men, being overweight and previous LBP episodes were statistically significantly lower in Subgroup 1, higher in Subgroup 2 and highest in Subgroup 3.ConclusionsFive distinct subgroups of MRI findings in the spine and SIJs were identified. The results indicate that SIJ MRI findings not only can be seen as a part of the spondyloarthritis disease entity, but also are associated with age, gender and being overweight. Furthermore, the results indicate that LBP patients with SIJ MRI findings are more disabled compared with patients without SIJ MRI findings, and that moderate to severe spinal degeneration and/or SIJ MRI findings may be associated with recurrent pain.Electronic supplementary materialThe online version of this article (doi:10.1186/s13075-016-1131-x) contains supplementary material, which is available to authorized users.

Perceived Risk of Low-Back Injury Among Four Occupations.

This study aimed to assess the perception of risk of low-back injury of individuals from four groups: office/administrative employees, dental workers (dentists/dental hygienists), firefighters, and undergraduate students. The concept of worker's perception of injury risk has been used to set safe material-handling limits and to determine compliance with health and safety regulations but has not been used to identify perceptual differences among occupations or potential deficiencies in risk awareness. Participants (N = 232) were presented with eight images of different low-back postures/tasks and were required to rate their perceived magnitude of low-back risk on a scale from 0 (no risk) to 10 (extreme risk). Office/administrative and dental workers rated postures higher than firefighters and students. Individuals from all groups perceived kyphotic postures as having a higher low-back risk than lordotic postures. Further, office and dental workers, compared to firefighters and students, perceived sitting postures to have a relatively higher level of risk, likely due to these postures being typically adopted by these individuals at work. No relationship between previous low-back pain and risk rating was observed in this study. Low-back injury risk perception varies between occupations/groups and may be a result of different exposures. The results of this study can potentially be used to implement occupation-specific training programs to ensure that the scientific research regarding low-back injuries is being properly conveyed to employees across all sectors.

Results after Lumbar Discectomy for Herniated Disc in Worker's Compensation Patients: more than 15 Years of Follow- up

Introduction Published literature has identified worker's compensation population to have worse results after lumbar discectomy for herniated disc compared with general population. However the advantage of complete follow-up due to its captive population is well know. This study aims to evaluate lumbar discectomy outcomes, prognostic factors and recurrence rate after more than15 years of follow-up. Material and Methods A retrospective review of 50 worker's compensation patients operated consecutively between 1997–1998 in Hospital del Trabajador for primary herniated lumbar disc was performed. Electronic medical records analysis was conducted until June 2015. Primary outcomes were surgical complications, sick leave, return to work, work compensation, chronic postoperative low back pain and reoperation for recurrent lumbar disc herniation. Statistical analysis looking for prognostic factors in lumbar discectomy evolution was realized. Results We found 44 men and 6 women with a mean age of 36.5 (22–66) years. One hundred percent follow-up was achieved with a mean time of 18 (17.5–18.5) years. Most patients were light workers (58%). Lumbar herniated discs were mostly located at L5-S1 ( n = 35) followed by L4-L5 ( n = 12). 74% were posterolateral disc herniations and 22% were central. Mean preoperative, postoperative and total sick leave was 37.9 (1–109), 57.7 (28–175) and 95.6 (35–203) days respectively. An intraoperative complication rate of 2% was seen, while no infectious complications were reported. All patients returned to work, most of them to the same work (88%). 10% received work compensation. During follow up, 32% (16/50) required a new period of sick leave with a mean sick free time of 64.4 (4–135) months. 8 of these were due to a new episode of low back pain. The rest were 6 recurrent disc herniations and 2 other level disc herniations that required new surgery. At 5, 10 and more than 15 years of follow-up recurrence rate was 8%, 12% and 12% respectively, while chronic low back pain was 8%, 10% and 12% respectively. Psychological disorders found in 18% patients were associated with longer sick leave (62.8 versus 56.6 days. p &lt; 0.05) and higher need of work compensation (33% versus 4.9%, p &lt; 0.05). Patients with preoperative infiltrations (33/50) required more new periods of sick leave (33% versus 5.9%, p &lt; 0.05). Age, type of work, previous low back pain episodes, disc herniation characteristics and preoperative sick leave showed no statistically significant association with postoperative evolution. Conclusion As found in previous study, the presence of physiological disorders, also known as non-organic symptoms, and preoperative infiltrations were associated with worse results after lumbar discectomy. This manifested as longer sick leave periods and higher need of work compensation. Age, type of work, disc herniation characteristics and preoperative sick leave did not represent bad prognostic factors. Disc herniation recurrence rate increased from 8% at 5 years of follow-up to 12% at 10 and over 15 years of follow-up. This recurrence rate is similar to the one reported in literature. Ten percent of postoperative chronic low back pain at 10 years and 12% with more than 15 years of follow-up was observed.