Previous systematic reviews have reported positive associations between Modic changes (MCs) and low back pain (LBP), but due to their narrow scope and new primary studies, there is a need for a ...comprehensive systematic review. Our objectives were to investigate if MCs are associated with non-specific LBP and/or activity limitation and if such associations are modified by other factors.
A protocol for this review was registered at PROSPERO prior to commencing the work (PROSPERO record: CRD42015017350). The MEDLINE, CINAHL and EMBASE databases were searched for relevant studies from first record to June 15th 2016. Prospective or retrospective cross-sectional cohort studies and case-control studies including people of all ages from general, working and clinical study populations were eligible for inclusion. Risk of bias assessment and data extraction for associations and potential modifiers were completed independently by pairs of reviewers. Meta-analysis was performed for homogeneous studies and presented as odds ratios (OR) with 95% CI.
In all, 5210 citations were identified and 31 studies were included. One study had low risk of bias. Fifteen studies (48%) reported statistically significant positive associations between MCs and LBP and one study found a statistically significant negative association. Meta-analysis performed for studies using concordant pain with provocative discography as the clinical outcome resulted in an OR of 4.01 (1.52-10.61). One of seven studies reported a statistically significant positive association between MCs and activity limitation. Lumbar disc level and disc degeneration were found to modify the association between MCs and LBP.
The results from this comprehensive systematic review indicate that the associations between MCs and LBP-related outcomes are inconsistent. The high risk of bias and the heterogeneity in terms of study samples, clinical outcomes and prevalence estimates of MCs and LBP may explain these findings. It is likely that new studies with low risk of bias will affect the direction and strength of these associations.
We investigated the longitudinal associations between physical activity (PA), lumbar multifidus morphology, and impactful low back pain (LBP) in young people. Nine-year-old children were recruited ...from 25 primary schools and followed up at age 13, 16, and 21 years. We measured PA with accelerometers at age 9, 13, and 16; quantified patterns of lumbar multifidus intramuscular adipose tissue (IMAT) change from 13 to 16 years using magnetic resonance imaging; and recorded LBP and its impact with standardised questionnaires and interviews. Associations were examined with crude and adjusted logistic or multinomial models and reported with odds ratios (OR) or relative risk ratios (RRR). We included data from 364 children (meanSD age = 9.7.4 years). PA behaviour was not associated with LBP. Having persistently high IMAT levels at age 13 and 16 was associated with greater odds of LBP (OR95% CI = 2.981.17 to 7.58). Increased time in moderate and vigorous intensity PA was associated with a lower risk of higher IMAT patterns (RRR95% CI = .67.46 to .96 to .74.55 to 1.00). All associations became non-significant after adjusting for sex and body mass index (BMI). Future studies investigating the relationships between PA behaviour, lumbar multifidus IMAT, and impactful LBP should account for potential confounding by sex and BMI.
Cross-sectional cohort study of a general population.
To investigate "abnormal" lumbar spine magnetic resonance imaging (MRI) findings, and their prevalence and associations with low back pain (LBP).
...The clinical relevance of various "abnormal" findings in the lumbar spine is unclear. Distinguishing between inevitable age-related findings and degenerative findings with deleterious consequences is a challenge.
Lumbar spine MRI was obtained in 412, 40-year-old individuals. Predefined "abnormal" MRI findings were interpreted without any knowledge of patient symptoms. Associations between MRI abnormalities and LBP were calculated using odds ratios. The "overall picture" of each MRI finding was established on the basis of the frequencies, diagnostic values, and the strength and consistency of associations.
Most "abnormal" MRI findings were found at the lowest lumbar levels. Irregular nucleus shape and reduced disc height were common (>50% of individuals). Relatively common (25% to 50%) were hypointense disc signal, anular tears, high intensity zones, disc protrusions, endplate changes, zygapophyseal joint degeneration, asymmetry, and foraminal stenosis. Nerve root compromise, Modic changes, central spinal stenosis, and anterolisthesis/retrolisthesis were rare (<25%). Most strongly associated with LBP were Modic changes and anterolisthesis (odds ratios >4). Significantly positive associations with all LBP variables were seen for hypointense disc signals, reduced disc height, and Modic changes. All disc "abnormalities" except protrusion were moderately associated with LBP during the past year.
Most degenerative disc "abnormalities" were moderately associated with LBP. The strongest associations were noted for Modic changes and anterolisthesis. Further studies are needed to define clinical relevance.
Taking the natural course of recurrent and fluctuating low back pain (LBP) seen in longitudinal studies of adults into consideration, the aetiology and development of LBP in children and adolescents ...also needs to be reflected in a long-term course. Therefore, a systematic critical literature review was undertaken to assess the natural course of LBP in the general population from childhood through adolescence to young adulthood.
A systematic literature search was conducted in MEDLINE, EMBASE, CINAHL and PsycINFO with synonyms of search terms for 1) low back pain; 2) natural course; 3) cohort study and 4) children. Records in English, German, French, Danish, Swedish, and Norwegian were included. To assess the methodological quality of the studies, the NIH quality assessment checklist for cohort studies was adapted and risk of bias was assessed on a study level. Two authors independently reviewed selected studies, assessed quality, and extracted data. A synthesis of results in relation to the natural course of LBP was created.
Totally, 3373 records were identified, eight articles were included for quality assessment, and finally, four studies of good to fair quality were included for synthesis of results. Indication of three common patterns of LBP were identified across studies and labelled as 1) ´children and adolescents with no LBP or low probability of LBP´ (49 to 53%), 2) ´children and adolescents with fluctuation of LBP´ (16 to 37%) and 3) ´children and adolescents with repeated reporting of LBP´ (< 1 to 10%).
Although methodological heterogeneity, mainly due to different age ranges, an indication of a natural course of LBP was seen across studies. The majority of children and adolescents repeatedly reporting no or low probability of LBP. With recall periods between one week to three months and sampling rates ranging from one to four years, a very low rate repeatedly reported LBP, and approximately one-fifth to one-third of children and adolescents had fluctuating reports of LBP. A need of future research of LBP trajectories with short reporting period lengths and narrower sampling windows in a long-term perspective is emphasized in order to study childhood influences on the development of LBP throughout life.
Few non-surgical, longitudinal studies have evaluated the relations between spinal degeneration, lumbar multifidus muscle (LMM) quality, and clinical outcomes. None have assessed the potential ...mediating role of the LMM between degenerative pathology and 12-month clinical outcomes. This prospective cohort study used baseline and 12-month follow-up data from 569 patients conservatively managed for low back or back-related leg pain to estimate the effects of aggregate degenerative lumbar MRI findings and LMM quality on 12-month low back and leg pain intensity (0-10) and disability (0-23) outcomes, and explored the mediating role of LMM quality between degenerative findings and 12-month clinical outcomes. Adjusted mixed effects generalized linear models separately estimated the effect of aggregate spinal pathology and LMM quality. Mediation models estimated the direct and indirect effects of pathology on leg pain, and pathology and LMM quality on leg pain, respectively. Multivariable analysis identified a leg pain rating change of 0.99 0.14; 1.84 (unstandardized beta coefficients 95% CI) in the presence of ≥ 4 pathologies, and a disability rating change of - 0.65 - 0.14; - 1.16 for each 10% increase in muscle quality, but no effect on back pain intensity. Muscle quality had a non-significant mediating role (13.4%) between pathology and leg pain intensity. The number of different pathologies present demonstrated a small effect on 12-month leg pain intensity outcomes, while higher LMM quality had a direct effect on 12-month disability ratings but no mediating effect between pathology and leg pain. The relations between degenerative pathology, LMM quality, and pain-related outcomes appear complex and may include independent pathways.
Individual study results have demonstrated unclear relationships between neurocompressive disorders and paraspinal muscle morphology. This systematic review aimed to synthesize current evidence ...regarding the relationship lumbar neurocompressive disorders may have with lumbar paraspinal muscle morphology.
Searches were conducted in seven databases from inception through October 2017. Observational studies with control or comparison groups comparing herniations, facet degeneration, or canal stenosis to changes in imaging or biopsy-identified lumbar paraspinal muscle morphology were included. Data extraction and risk of bias assessment were performed by review author pairs independent of one another. Morphological differences between individuals with and without neurocompressive disorders were compared qualitatively, and where possible, standardised mean differences were obtained.
Twenty-eight studies were included. Lumbar multifidus fiber diameter was smaller on the side of and below herniation for type I SMD: -0.40 (95% CI = -0.70, -0.09) and type II fibers SMD: -0.38 (95% CI = -0.69, -0.06) compared to the unaffected side. The distribution of type I fibers was greater on the herniation side SMD: 0.43 (95% CI = 0.03, 0.82). Qualitatively, two studies assessing small angular fiber frequency and fiber type groupings demonstrated increases in these parameters below the herniation level. For diagnostic imaging meta-analyses, there were no consistent differences across the various assessment types for any paraspinal muscle groups when patients with herniation served as their own control. However, qualitative synthesis of between-group comparisons reported greater multifidus and erector spinae muscle atrophy or fat infiltration among patients with disc herniation and radiculopathy in four of six studies, and increased fatty infiltration in paraspinal muscles with higher grades of facet joint degeneration in four of five studies. Conflicting outcomes and variations in study methodology precluded a clear conclusion for canal stenosis.
Based on mixed levels of risk of bias data, in patients with chronic radiculopathy, disc herniation and severe facet degeneration were associated with altered paraspinal muscle morphology at or below the pathology level. As the variability of study quality and heterogeneous approaches utilized to assess muscle morphology challenged comparison across studies, we provide recommendations to promote uniform measurement techniques for future studies.
PROSPERO 2015: CRD42015012985.
Because training of the lumbar muscles is a commonly recommended intervention in low back pain (LBP), it is important to clarify whether lumbar muscle atrophy is related to LBP. Fat infiltration ...seems to be a late stage of muscular degeneration, and can be measured in a non-invasive manner using magnetic resonance imaging. The purpose of this study was to investigate if fat infiltration in the lumbar multifidus muscles (LMM) is associated with LBP in adults and adolescents.
In total, 412 adults (40-year-olds) and 442 adolescents (13-year-olds) from the general Danish population participated in this cross-sectional cohort study. People with LBP were identified through questionnaires. Using MRI, fat infiltration of the LMM was visually graded as none, slight or severe. Odds ratios were calculated for both age groups, taking into account sex, body composition and leisure time physical activity for both groups, and physical workload (in adults only) or daily bicycling (in adolescents only).
Fat infiltration was noted in 81% of the adults but only 14% of the adolescents. In the adults, severe fat infiltration was strongly associated with ever having had LBP (OR 9.2; 95% CI 2.0-43.2), and with having LBP in the past year (OR 4.1; 1.5-11.2), but there was no such association in adolescents. None of the investigated moderating factors had an obvious effect on the OR in the adults.
Fat infiltration in the LMM is strongly associated with LBP in adults only. However, it will be necessary to quantify these measurements objectively and to investigate the direction of this link longitudinally in order to determine if the abnormal muscle is the cause of LBP or vice versa.
Abstract
Associations between multifidus muscle morphology and degenerative pathologies have been implied in patients with non-specific low back pain, but it is unknown how these are influenced by ...pathology severity, number, or distribution. MRI measures of pure multifidus muscle cross-sectional area (CSA) were acquired from 522 patients presenting with low back and/or leg symptoms in an outpatient clinic. We explored cross-sectional associations between the presence, distribution, and/or severity of lumbar degenerative pathologies (individually and in aggregate) and muscle outcomes in multivariable analyses (beta coefficients 95% CI). We identified associations between lower pure multifidus muscle CSA and disc degeneration (at two or more levels): − 4.51 − 6.72; − 2.3, Modic 2 changes: − 4.06 − 6.09; − 2.04, endplate defects: − 2.74 − 4.58; − 0.91, facet arthrosis: − 4.02 − 6.26; − 1.78, disc herniations: − 3.66 − 5.8; − 1.52, and when > 5 pathologies were present: − 6.77 − 9.76; − 3.77, with the last supporting a potential dose–response relationship between number of spinal pathologies and multifidus morphology. Our findings could hypothetically indicate that these spinal and muscle findings: (1) are part of the same degenerative process, (2) result from prior injury or other common antecedent events, or (3) have a directional relationship. Future longitudinal studies are needed to further examine the complex nature of these relationships.
Reassuring patient education and exercise therapy are widely recommended interventions for back pain in clinical guidelines. However, many patients are offered non-guideline endorsed options, and ...strategies for effective implementation of guideline-based care have not yet been developed. This protocol outlines the evaluation of a strategy for nationwide implementation of standardised patient education and exercise therapy for people with persistent or recurrent back pain in a hybrid implementation-effectiveness design. The strategy and the evaluation were planned using the framework of the Behaviour Change Wheel.
The main activity of the implementation strategy is a two-days course for physiotherapists and chiropractors in delivering patient education and exercise therapy that is aimed at supporting patient self-management. This comes with ready-to-use patient education materials and exercise programs. The clinical intervention is a group-based program consisting of two sessions of patient education and 8 weeks of supervised exercises. The program uses a cognitive-behavioural approach and the aim of the exercise component is to restore the patient's ability and confidence to move freely. The implementation process is evaluated in a dynamic process monitoring the penetration, adoption and fidelity of the clinical intervention. The clinical intervention and potential effect mechanisms will be evaluated at the patient-level using measures of knowledge, skills, beliefs, performance, self-efficacy and success in self-management. The education of clinicians will be evaluated via clinician-level outcomes, including the Pain Attitudes and Beliefs Scale, the Practitioner Confidence Scale, and the Determinants of Implementation Behaviour Questionnaire. Effects at a national level will be investigated via data from national registries of health care utilisation and sick-leave.
This implementation-effectiveness study is designed to evaluate the process of implementing an evidence-based intervention for back pain. It will inform the development of strategies for implementing evidence-based care for musculoskeletal pain conditions, it will enhance the understanding of mechanisms for developing patient self-management skills, and it will demonstrate the outcomes that are achievable in everyday clinical practice.
ClinicalTrials.gov NCT03570463 . Registered 27 June 2018.
Lumbar disc degeneration seen on magnetic resonance imaging (MRI) is defined as loss of signal intensity and/or disc height, alone or in combination with other MRI findings. The MRI findings and ...thresholds used to define disc degeneration vary in the literature, and their associations with low back pain (LBP) remain uncertain.
To explore how various thresholds of lumbar disc degeneration alter the association between disc degeneration and self-reported LBP.
An exploratory, cross-sectional cohort study of a general population. Participants in the cohort 'Backs-on-Funen' had MRI scans and completed questionnaires about LBP at ages 41, 45 and 49 years. The MRI variables, signal intensity (Grades 0-3) and disc height (Grades 0-3), were dichotomised at different thresholds. Logistic regression analyses were used to determine associations. Arbitrarily, a difference in odds ratio (OR) of > 0.5 between thresholds was considered clinically relevant. Receiver Operating Characteristic curves were used to investigate differences between diagnostic values at each threshold.
At age 41, the difference in ORs between signal loss and LBP exceeded 0.5 between the thresholds of ≥2 (OR = 2.02) and = 3 (OR = 2.57). Difference in area under the curves (AUC) was statistically significant (p = 0.02). At ages 45 and 49, the difference in ORs exceeded 0.5 between the thresholds of ≥2 and = 3, but the differences between AUC were not statistically significant. At age 41, the difference in ORs between disc height loss and LBP at the thresholds of ≥1 (OR = 1.44) and ≥ 2 (OR = 2.53) exceeded 0.5. Differences in AUC were statistically significant (p = 0.004). At age 49, differences in ORs exceeded 0.5 (OR = 2.49 at the ≥1 threshold, 1.84 at ≥2 and 0.89 at =3). Differences between AUC were not statistically significant.
The results suggest that the thresholds used to define the presence of lumbar disc degeneration influence how strongly it is associated with LBP. Thresholds at more severe grades of disc signal and disc height loss were more strongly associated with LBP at age 41, but thresholds at moderate grades of disc degeneration were most strongly associated with LBP at ages 45 and 49.