Spinal degeneration and lumbar multifidus muscle quality may independently affect clinical outcomes in patients conservatively managed for low back or leg pain.

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.

Health trends in Canada 1990-2019: An analysis for the Global Burden of Disease Study.

OBJECTIVE: Monitoring trends in key population health indicators is important for informing health policies. The aim of this study was to examine population health trends in Canada over the past 30 years in relation to other countries. METHODS: We used data on disability-adjusted life years (DALYs), years of life lost (YLL), years lived with disability, life expectancy (LE), and child mortality for Canada and other countries between 1990 and 2019 provided by the Global Burden of Disease Study. RESULTS: Life expectancy, age-standardized YLL, and age-standardized DALYs all improved in Canada between 1990 and 2019, although the rate of improvement has leveled off since 2011. The top five causes of all-age DALYs in Canada in 2019 were neoplasms, cardiovascular diseases, musculoskeletal disorders, neurological disorders, and mental disorders. The greatest increases in all-age DALYs since 1990 were observed for substance use, diabetes and chronic kidney disease, and sense organ disorders. Age-standardized DALYs declined for most conditions, except for substance use, diabetes and chronic kidney disease, and musculoskeletal disorders, which increased by 94.6%, 14.6%, and 7.3% respectively since 1990. Canada's world ranking for age-standardized DALYs declined from 9th place in 1990 to 24th in 2019. CONCLUSION: Canadians are healthier today than in 1990, but progress has slowed in Canada in recent years in comparison with other high-income countries. The growing burden of substance abuse, diabetes/chronic kidney disease, and musculoskeletal diseases will require continued action to improve population health.

RéSUMé: OBJECTIF: La surveillance des tendances des indicateurs clés de la santé de la population est importante pour éclairer les politiques de santé. Dans cette étude, nous avons examiné les tendances de la santé de la population au Canada au cours des 30 dernières années par rapport à d'autres pays. MéTHODES: Nous avons utilisé des données sur les années de vie ajustées en fonction de l'incapacité (DALY), les années de vie perdues (YLL), les années vécues avec un handicap, l'espérance de vie (LE) et la mortalité infantile pour le Canada et d'autres pays entre 1990 et 2019, fournies par l'Étude mondiale sur le fardeau de la maladie. RéSULTATS: L'espérance de vie, les YLL ajustées selon l'âge et les DALY ajustées selon l'âge ont tous connu une amélioration au Canada entre 1990 et 2019, bien que le taux d'amélioration se soit stabilisé depuis 2011. Les cinq principales causes des DALY pour tous les âges au Canada en 2019 étaient les néoplasmes, les maladies cardiovasculaires, les affections musculosquelettiques, les affections neurologiques et les troubles mentaux. Les plus fortes augmentations des DALY pour tous les âges depuis 1990 ont été observées pour l'usage de substances, le diabète et les maladies rénales chroniques, ainsi que les troubles des organes sensoriels. Les DALY ajustées selon l'âge ont diminué pour la plupart des conditions, à l'exception de l'usage de substances, du diabète et des maladies rénales chroniques, ainsi que des troubles musculosquelettiques, qui ont augmenté de 94,6 %, 14,6 % et 7,3 % respectivement depuis 1990. Le classement mondial du Canada pour les DALY ajustées selon l'âge est diminué de la 9ième place en 1990 à la 24ième place en 2019. CONCLUSION: Les Canadiens sont en meilleure santé aujourd'hui qu'en 1990, mais les progrès se sont ralentis ces dernières années par rapport à d'autres pays à revenu élevé. La croissance du fardeau lié à l'abus de substances, au diabète/maladies rénales chroniques et aux affections musculosquelettiques exigera des actions continues pour améliorer la santé de la population.

Lumbar multifidus muscle morphology is associated with low back-related pain duration, disability, and leg pain: A cross-sectional study in secondary care.

BACKGROUND: Systematic reviews and studies exploring associations between morphologic change of paraspinal muscles and low back pain or related outcomes such as disability, radiculopathy, and physical workload, have reported conflicting results. This study explores the associations between lumbar multifidus muscle quality and clinical outcomes relating to low back pain. METHODS: Cross-sectional study of spinal clinic outpatients presenting with a primary complaint of low back and/or leg symptoms. Univariable and multivariable regression models were used to investigate associations between MRI-based multifidus muscle cross-sectional area at L4 and L5 and clinical outcomes for low back pain, leg pain, disability, restricted motion, and strenuous nature of work. Results were reported with ß-coefficients, odds ratios (OR), or incidence rate ratios (IRR) and their corresponding 95% confidence intervals, based on a 10% difference in muscle quality for each clinical variable. Multivariable analyses were adjusted for age, sex, and BMI. RESULTS: 875 patients [487 females; mean (SD) age: 43.6 (10.2) years] were included. In the multivariable analyses, muscle quality was significantly associated with disability (0-23 scale) [ß: -0.74, 95% CI: -1.14, -0.34], leg pain intensity (0-10 scale) [ß: -0.25, 95% CI: -0.46, -0.03], and current pain duration of more than 12 months [OR: 1.27, 95% CI: 1.03, 1.55]. No associations were found for low back pain intensity, morning stiffness, painful active range of motion, or work nature. CONCLUSIONS: Patients with higher lumbar multifidus muscle quality reported lower levels of low back pain-related disability and leg pain intensity, indicating that muscle quality may play a role in the etiology of lumbar spine disorders. However, the clinical importance of these associations is uncertain due to the low magnitude of identified associations. Future longitudinal studies are needed to understand the effect of lumbar multifidus muscle quality on lumbar-related pain and disability.

Prediction of 2-year clinical outcome trajectories in patients undergoing anterior cervical discectomy and fusion for spondylotic radiculopathy.

OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) is often described as the gold standard surgical technique for cervical spondylotic radiculopathy. Although outcomes are considered favorable, there is little prognostic evidence to guide patient selection for ACDF. This study aimed to 1) describe the 24-month postoperative trajectories of arm pain, neck pain, and pain-related disability; and 2) identify perioperative prognostic factors that predict trajectories representing poor clinical outcomes. METHODS: In this retrospective cohort study, patients with cervical spondylotic radiculopathy who underwent ACDF at 1 of 12 orthopedic or neurological surgery centers were recruited. Potential outcome predictors included demographic, health, clinical, and surgery-related prognostic factors. Surgical outcomes were classified by trajectories of arm pain intensity, neck pain intensity (numeric pain rating scales), and pain-related disability (Neck Disability Index) from before surgery to 24 months postsurgery. Trajectories of postoperative pain and disability were estimated with latent class growth analysis, and prognostic factors associated with poor outcome trajectory were identified with robust Poisson models. RESULTS: The authors included data from 352 patients (mean age 50.9 [SD 9.5] years; 43.8% female). The models estimated that 15.5%-23.5% of patients followed a trajectory consistent with a poor clinical outcome. Lower physical and mental health-related quality of life, moderate to severe risk of depression, and longer surgical wait time and procedure time predicted poor postoperative trajectories for all outcomes. Receiving compensation and smoking additionally predicted a poor neck pain outcome. Regular exercise, physiotherapy, and spinal injections before surgery were associated with a lower risk of poor disability outcome. Patients who used daily opioids, those with worse general health, or those who reported predominant neck pain or a history of depression were at greater risk of poor disability outcome. CONCLUSIONS: Patients who undergo ACDF for cervical spondylotic radiculopathy experience heterogeneous postoperative trajectories of pain and disability, with 15.5%-23.5% of patients experiencing poor outcomes. Demographic, health, clinical, and surgery-related prognostic factors can predict ACDF outcomes. This information may further assist surgeons with patient selection and with setting realistic expectations. Future studies are needed to replicate and validate these findings prior to confident clinical implementation.

Associations between cardiovascular disease risk factors and spinal pain may be moderated by sex and health-related physical activity (CHAMPS Study-DK).

BACKGROUND: Spinal pain has been previously linked with cardiovascular disease risk factors in children. This study investigated the prospective associations between cardiovascular disease risk factors and non-traumatic spinal pain occurrences in children, and examined the moderating role of sex and health-related physical activity in these relationships. METHODS: We used prospective data from the Childhood Health, Activity, and Motor Performance School Study Denmark (CHAMPS Study-DK). The exposure variables were a clustered cardiovascular risk score and homeostasis assessment model-estimated insulin resistance (HOMA-IR) score collected in 2008 and 2010. The spinal pain outcome comprised the number of weeks of non-traumatic spinal pain from 2008-2010 and 2010-2012. Potential confounders included age, sex, and time spent in moderate-to-vigorous intensity physical activity. We constructed age-adjusted mixed negative binominal regression models to investigate the prospective associations of cardiovascular disease risk factors and non-traumatic spinal pain, while considering the potential moderating roles of sex and physical activity in these relationships. RESULTS: Girls with low HOMA-IR scores and boys with low clustered cardiovascular disease risk scores, who engaged in higher levels of moderate-to-vigorous physical activity, reported more weeks of spinal pain, compared to girls with high HOMA-IR scores (p = 0.001) and boys with high clustered cardiovascular disease risk scores (p = 0.024). whereas boys with higher clustered cardiovascular disease risk who had less time in moderate-to-vigorous physical activity reported more weeks of spinal pain than boys with low clustered cardiovascular disease risk score (p = 0.024). CONCLUSION: Our results show that cardiovascular disease risk factors are related to future occurrences of non-traumatic spinal pain. However, these relationships appear complex and dependent on the nature of the interactions with sex and physical activity.

No associations between C-reactive protein and spinal pain trajectories in children and adolescents (CHAMPS study-DK).

Preliminary evidence points to a link between C-reactive protein (CRP) and spinal pain in adults. However, there is a paucity of research in younger populations. Therefore, we aimed to determine associations between CRP and spinal pain in childhood and adolescence. We identified trajectories of spinal pain from childhood to adolescence and investigated the associations between CRP and trajectory subgroups. Six- to 11-year-old children from 13 primary schools, were followed from October 2008 and until 2014. High-sensitivity CRP collected at baseline (2008) was measured using serum samples. The outcome was the number of weeks with non-traumatic spinal pain between November 2008 and June 2014. We constructed a trajectory model to identify different spinal pain trajectory subgroups. The associations between CRP and spinal pain trajectory subgroups were modelled using mixed-effects multinominal logistic regression. Data from 1556 participants (52% female), with a mean age of 8.4 years at baseline, identified five spinal pain trajectory subgroups: "no pain" (55.3%), "rare" (23.7%), "rare, increasing" (13.6%), "moderate, increasing" (6.1%), and "early onset, decreasing" (1.3%). There were no differences in baseline high-sensitivity CRP levels between spinal pain trajectory subgroups. Thus, the heterogeneous courses of spinal pain experienced were not defined by differences in CRP at baseline.

The effect of the inclusion of trunk-strengthening exercises to a multimodal exercise program on physical activity levels and psychological functioning in older adults: secondary data analysis of a randomized controlled trial.

BACKGROUND: Engaging in multimodal exercise program helps mitigate age-related decrements by improving muscle size, muscle strength, balance, and physical function. The addition of trunk-strengthening within the exercise program has been shown to significantly improve physical functioning outcomes. Whether these improvements result in improved psychological outcomes associated with increased physical activity levels requires further investigation. We sought to explore whether the inclusion of trunk-strengthening exercises to a multimodal exercise program improves objectively measured physical activity levels and self-reported psychological functioning in older adults. METHOD: We conducted a secondary analysis within a single-blinded parallel-group randomized controlled trial. Sixty-four healthy older (≥ 60 years) adults were randomly allocated to a 12-week walking and balance exercise program with (n = 32) or without (n = 32) inclusion of trunk strengthening exercises. Each program involved 12 weeks of exercise training, followed by a 6-week walking-only program (identified as detraining). Primary outcome measures for this secondary analysis were physical activity (accelerometry), perceived fear-of-falling, and symptoms of anxiety and depression. RESULTS: Following the 12-week exercise program, no significant between-group differences were observed for physical activity, sedentary behaviour, fear-of-falling, or symptoms of anxiety or depression. Significant within-group improvements (adjusted mean difference [95%CI]; percentage) were observed in moderate-intensity physical activity (6.29 [1.58, 11.00] min/day; + 26.3%) and total number of steps per min/day (0.81 [0.29 to 1.33] numbers or + 16.3%) in trunk-strengthening exercise group by week 12. With respect to within-group changes, participants in the walking-balance exercise group increased their moderate-to-vigorous physical activity (MVPA) (4.81 [0.06 to 9.56] min/day; + 23.5%) and reported reduction in symptoms of depression (-0.26 [-0.49 to -0.04] points or -49%) after 12 weeks of the exercise program. The exercise-induced increases in physical activity levels in the trunk-strengthening exercise group were abolished 6-weeks post-program completion. While improvements in physical activity levels were sustained in the walking-balance exercise group after detraining phase (walking only). CONCLUSIONS: The inclusion of trunk strengthening to a walking-balance exercise program did not lead to statistically significant between-group improvements in physical activity levels or psychological outcomes in this cohort following completion of the 12-week exercise program. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ACTRN12613001176752), registered on 28/10/2013.

Spinal degeneration is associated with lumbar multifidus morphology in secondary care patients with low back or leg pain.

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.

Postoperative recovery patterns following discectomy surgery in patients with lumbar radiculopathy.

This retrospective study of prospectively collected data aimed to identify unique pain and disability trajectories in patients following lumbar discectomy surgery. Patients of this study population presented chiefly with lumbar radiculopathy and underwent discectomy surgery from thirteen sites enrolled in the CSORN registry. Outcome variables of interest included numeric rating scales for leg/back pain and modified Oswestry disability index scores at baseline, 3, 12, and 24 months post-operatively. Latent class growth analysis was used to identify distinct courses in each outcome. Data from 524 patients revealed three unique trajectories for leg pain (excellent = 18.4%, good = 55.4%, poor = 26.3%), disability (excellent = 59.7%, fair = 35.6%, poor = 4.7%) and back pain (excellent = 13.0%, good = 56.4%, poor = 30.6%). Construct validity was supported by statistically significant differences in the proportions of patients attaining the criteria for minimal important change (MIC; 30%) or clinical success in disability (50% or Oswestry score ≤ 22) (p < 0.001). The variable proportions of patients belonging to poor outcome trajectories shows a disconnect between improved disability and persistence of pain. It will be beneficial to incorporate this information into the realm of patient expectation setting in concert with future findings of potential factors predictive of subgroup membership.

The relationships between physical activity, lumbar multifidus muscle morphology, and low back pain from childhood to early adulthood: a 12-year longitudinal study.

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 (mean[SD] 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 (OR[95% CI] = 2.98[1.17 to 7.58]). Increased time in moderate and vigorous intensity PA was associated with a lower risk of higher IMAT patterns (RRR[95% 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.

Spinal pain in childhood: prevalence, trajectories, and diagnoses in children 6 to 17 years of age.

This study aimed to investigate the trajectories of spinal pain frequency from 6 to 17 years of age and describe the prevalence and frequency of spinal pain and related diagnoses in children following different pain trajectories. First through fifth-grade students from 13 primary schools were followed for 5.5 years. Occurrences of spinal pain were reported weekly via text messages. Children reporting spinal pain were physically evaluated and classified using International Classification of Disease criteria. Trajectories of spinal pain frequency were modeled from age 6 to 17 years with latent class growth analysis. We included data from 1556 children (52.4% female, mean (SD) baseline age = 9.1 (1.9) years) and identified 10,554 weeks of spinal pain in 329,756 weeks of observation. Sixty-three percent of children reported one or more occurrences of spinal pain. We identified five trajectories of spinal pain frequency. Half the children (49.8%) were classified as members of a "no pain" trajectory. The remaining children followed "rare" (27.9%), "rare, increasing" (14.5%), "moderate, increasing" (6.5%), or "early-onset, decreasing" (1.3%) spinal pain trajectories. The most common diagnoses in all trajectory groups were non-specific (e.g., "back pain"). Tissue-specific diagnoses (e.g., muscle strain) were less common and pathologies (e.g., fracture) were rare.  Conclusion: From childhood through adolescence, spinal pain was common and followed heterogeneous courses comprising stable, increasing, and early-onset trajectories. These findings accord with recommendations from adult back pain guidelines that most children with spinal pain can be reassured that they do not have a serious disease and encouraged to stay active. What is Known: • Spinal pain imposes a large burden on individuals and society. • Although many people first experience the condition in childhood, little is known about the developmental trajectories of spinal pain from childhood to adolescence. What is New: • Data from 1556 children and 329,756 participant weeks showed five unique spinal pain trajectories from 6 to 17 years: most children rarely reported spinal pain, while one in five followed increasing or early-onset trajectories. • Most pain occurrences were non-specific; pathological diagnoses were rare.

Effect of dry needling on lumbar muscle stiffness in patients with low back pain: A double blind, randomized controlled trial using shear wave elastography.

BACKGROUND: Dry needling treatment focuses on restoring normal muscle function in patients with musculoskeletal pain; however, little research has investigated this assertion. Shear wave elastography (SWE) allows quantification of individual muscle function by estimating both resting and contracted muscle stiffness. OBJECTIVE: To compare the effects of dry needling to sham dry needling on lumbar muscle stiffness in individuals with low back pain (LBP) using SWE. METHODS: Sixty participants with LBP were randomly allocated to receive one session of dry needling or sham dry needling treatment to the lumbar multifidus and erector spinae muscles on the most painful side and spinal level. Stiffness (shear modulus) of the lumbar multifidus and erector spinae muscles was assessed using SWE at rest and during submaximal contraction before treatment, immediately after treatment, and 1 week later. Treatment effects were estimated using linear mixed models. RESULTS: After 1 week, resting erector spinae muscle stiffness was lower in individuals who received dry needling than those that received sham dry needling. All other between-groups differences in muscle stiffness were similar, but non-significant. CONCLUSION: Dry needling appears to reduce resting erector spinae muscle following treatment of patients with LBP. Therefore, providers should consider the use of dry needling when patients exhibit aberrant stiffness of the lumbar muscles.

Vigorous physical activity is important in maintaining a favourable health trajectory in active children: the CHAMPS Study-DK.

Physical activity (PA) is critical to improving health factors such as weight, adiposity, and aerobic fitness. However, children who meet PA guideline recommendations demonstrate developmental differences in health-related outcomes. To investigate prospective associations between PA behaviour (overall PA and PA intensity) and trajectories of health-related factors among physically active children. This prospective study (2.5 years) included 391 children (baseline age: 8.1 ± 1.4 years; girls 36.3%) from ten public schools. All children performed 60-min or more of moderate-to-vigorous physical activity (MVPA) per day objectively measured. Trajectories of BMI, waist circumference, and aerobic fitness were constructed with a group-based multi-trajectory model. Three trajectory subgroups were identified: 'high fitness/normal weight' (48.4% of children), 'moderate fitness /normal weight' (42.5% of children), and 'low fitness/overweight-obese' (9.1% of children). Children performing higher overall PA, were less likely of being classified as members of the 'Low Fitness/Overweight-Obese' [Relative Risk Ratio (RRR and 95% CI) = 0.56 (0.37 to 0.85) compared to 'high fitness/normal weight' subgroup. Each additional 5% in light PA time was associated with approximately twofold [RRR 2.12 (1.24-3.61)] increased risk of being in the 'low fitness/overweight-obese' trajectory relative to the 'high fitness/normal weight' trajectory. Each additional 2% in vigorous-PA time was associated with a 42% and 85% reduced risk (relative to 'high fitness/normal weight') of being in the 'moderate fitness/normal weight' [RRR 0.58 (0.38-0.96)] and 'low fitness/overweight-obesity' [RRR 0.15 (0.06-0.37)] trajectory, respectively. Overall PA and additional time in vigorous-PA was associated with improved health-related outcomes, while light PA was negatively associated with health-related outcomes among children who adhere to PA guideline recommendations. Vigorous PA was the strongest predictor of the health trajectories. All PA guidelines for children should place greater emphasis on the importance of vigorous PA.

Effectiveness of Conservative Nonpharmacologic Therapies for Pain, Disability, Physical Capacity, and Physical Activity Behavior in Patients With Degenerative Lumbar Spinal Stenosis: A Systematic Review and Meta-Analysis.

OBJECTIVE: To investigate the effectiveness of conservative nonpharmacologic therapies on pain, disability, physical capacity, and physical activity outcomes in patients with degenerative lumbar spinal stenosis (LSS). DATA SOURCES: Systematic search of MEDLINE, EMBASE, CENTRAL, and PsycINFO from inception to November 4, 2019, without language restrictions. STUDY SELECTION: Pairs of review authors independently identified randomized controlled trials published in peer-reviewed scientific journals reporting on the effects of rehabilitation interventions on pain intensity (back or leg), disability, symptom severity, physical capacity, physical activity behavior, or adverse events (secondary outcome) in adults with LSS. The search identified 1718 records; data from 21 reports of 19 trials (1432 patients) were included. DATA EXTRACTION: Review author pairs independently extracted data and assessed included studies. We assessed risk of bias with the Cochrane tool, and overall study quality with the Grading of Recommendations Assessment, Development and Evaluation classification. DATA SYNTHESIS: We pooled data using random-effects meta-analyses; treatment effects were reported as mean differences (MD) and 95% confidence intervals (CI). Directed exercise and manual therapy was superior to self-directed or group exercise for improving short-term walking capacity (MD, 293.3 m; 95% CI, 61.7-524.9 m; low-quality evidence), back pain (MD, -1.1; 95% CI, -1.8 to -0.4; moderate quality evidence), leg pain (MD, -.9; 95% CI, -0.2 to -1.5; moderate-quality evidence), and symptom severity (MD, -0.3; 95% CI, -0.4 to -0.2; low quality evidence). There is very low quality evidence that rehabilitation is no better than surgery at improving intermediate- or long-term disability. Single trials provided conflicting evidence of effectiveness for a variety of therapies. CONCLUSIONS: For patients with LSS, there is low- to moderate-quality evidence that manual therapy with supervised exercises improves short-term walking capacity and results in small improvements in pain and symptom severity compared with self-directed or group exercise. The choice between rehabilitation and surgery for LSS is very uncertain owing to the very low quality of available evidence.

Multi-trajectory analysis of C-reactive protein and low back pain from adolescence to early adulthood.

PURPOSE: To identify low back pain (LBP) trajectories from early adolescence through to early adulthood and to investigate whether sustained levels of elevated subclinical C-reactive protein (CRP) are linked with these LBP trajectories. METHODS: We analysed longitudinal data from 1513 participants who were enrolled in the Raine Study cohort. Data on LBP with impact on daily living and CRP were collected at the ages of 14, 17, 20, and 22. We constructed group-based trajectory models to identify discrete trajectories of LBP with impact. We then evaluated how the CRP trajectories and the LBP with impact trajectories evolved jointly over time using a multi-trajectory analysis. RESULTS: The model identified three LBP trajectories. One subgroup included almost half the participants (46.1%) who had a consistently low probability of LBP. Another subgroup comprising 43.5% of participants had an increasing probability of LBP, while one in ten participants (10.4%) had a decreasing probability of LBP. There were no associations between elevated CRP and LBP trajectory subgroup membership. CONCLUSION: Although young people follow distinct trajectories of LBP, CRP trajectories do not appear to be a distinguishing factor of the LBP trajectories. Previously reported associations between CRP and LBP may be explained by comorbidity or other factors. Future studies undertaking trajectory analysis should consider comorbidity clusters. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Early life chronic inflammatory conditions predict low back pain in adolescence and young adulthood.

BACKGROUND: Associations between inflammatory conditions and low back pain (LBP) have been found frequently in older populations. However, the nature of these relationships in younger populations is unknown. This study aimed to investigate the associations between early life chronic or recurrent inflammatory conditions and impactful LBP in adolescence and young adulthood. METHODS: In this longitudinal study, we used data from the Raine Study Gen2 participants at the 1, 2, 3, 5, 8, 10, 14, 17, 20 and 22-year follow-ups (N = 2,868). Data were collected on inflammatory conditions from 1 to 22 years of age and occurrences of impactful LBP from 14 to 22 years of age. Longitudinal and cross-sectional associations between inflammatory conditions and impactful LBP occurrence were examined. Potential dose-response relationships between the number of inflammatory conditions and impactful LBP were also assessed. Logistic regression models were used in the analysis. RESULTS: Participants with respiratory or atopic conditions during childhood had increased odds of future impactful LBP in adolescence and young adulthood (odds ratio (OR) [95% confidence interval (CI)] = 1.29 [1.07, 1.54] and 1.23 [1.02, 1.49], respectively). There were cross-sectional associations between inflammatory conditions including respiratory, skin, musculoskeletal, autoimmune and atopic conditions, with impactful LBP. Participants with two illnesses and three or more illnesses had an increased odds (OR [95% CI] =1.68 [1.30, 2.18] and OR [95% CI] =2.12 [1.54, 2.89], respectively) of reporting impactful LBP. CONCLUSIONS: Overall, longitudinal and cross-sectional associations of respiratory and atopic conditions with impactful LBP in adolescence and young adulthood were identified. More evidence is needed to determine whether there is a causal relationship between chronic inflammatory conditions and impactful LBP. SIGNIFICANCE: Low back pain (LBP) is a prominent and significant health problem and associations between inflammatory conditions and LBP have been found frequently in older populations. We found that children with respiratory or atopic conditions and those with several chronic inflammatory conditions are at increased odds of impactful LBP in adolescence and young adulthood. In clinical practice and future research, there is a need to consider comorbidities also in younger populations.

Serious adverse events following lumbar spine mobilization or manipulation and potential associated factors: a systematic review protocol.

OBJECTIVES: The objectives of this review are to describe the serious adverse events reported in the literature following lumbopelvic mobilization and manipulation, and identify patient, provider, and/or treatment factors that may be associated with serious adverse events after these interventions. INTRODUCTION: Spinal mobilization and manipulation are types of conservative care commonly used to treat people with low back pain and other musculoskeletal conditions of the lumbar spine and pelvis. Although most adverse events following these interventions are benign and transient, serious adverse events have been reported mostly following spinal manipulative therapy. Given the significant impact serious adverse events can have on patients' lives, identifying factors that may be associated with serious adverse events following spinal mobilization and manipulation of the low back and pelvis would allow for a more specific pre-treatment screening, potentially reducing the occurrence of serious adverse events following these popular interventions and contributing to a safer treatment delivery. INCLUSION CRITERIA: This review will consider interventional and observational studies that report serious adverse events following lumbopelvic spinal mobilization or manipulation experienced by people of any age. Examples of serious adverse events include disc herniation, cauda equina syndrome, and vertebral fracture. METHODS: MEDLINE, Embase, CINAHL, PubMed, The Cochrane Database of Systematic Reviews/Central Register of Controlled Trials, and Index to Chiropractic Literature (ICL) databases will be searched as well as OpenGrey and ProQuest Dissertations and Theses. Two independent reviewers will screen titles and abstracts of identified references as well as the full text of identified studies, and extract data following a standardized data extraction form. Data will be summarized, categorized, and a comprehensive narrative summary will be presented. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO CRD42019122339.

Misinformation, chiropractic, and the COVID-19 pandemic.

BACKGROUND: In March 2020, the World Health Organization elevated the coronavirus disease (COVID-19) epidemic to a pandemic and called for urgent and aggressive action worldwide. Public health experts have communicated clear and emphatic strategies to prevent the spread of COVID-19. Hygiene rules and social distancing practices have been implemented by entire populations, including 'stay-at-home' orders in many countries. The long-term health and economic consequences of the COVID-19 pandemic are not yet known. MAIN TEXT: During this time of crisis, some chiropractors made claims on social media that chiropractic treatment can prevent or impact COVID-19. The rationale for these claims is that spinal manipulation can impact the nervous system and thus improve immunity. These beliefs often stem from nineteenth-century chiropractic concepts. We are aware of no clinically relevant scientific evidence to support such statements. We explored the internet and social media to collect examples of misinformation from Europe, North America, Australia and New Zealand regarding the impact of chiropractic treatment on immune function. We discuss the potential harm resulting from these claims and explore the role of chiropractors, teaching institutions, accrediting agencies, and legislative bodies. CONCLUSIONS: Members of the chiropractic profession share a collective responsibility to act in the best interests of patients and public health. We hope that all chiropractic stakeholders will view the COVID-19 pandemic as a call to action to eliminate the unethical and potentially dangerous claims made by chiropractors who practise outside the boundaries of scientific evidence.

Developmental Trajectories of Body Mass Index, Waist Circumference, and Aerobic Fitness in Youth: Implications for Physical Activity Guideline Recommendations (CHAMPS Study-DK).

OBJECTIVES: Describe the trajectories of body mass index (BMI), waist circumference, and aerobic fitness in children and identify different outcomes of guideline-recommended physical activity (PA) in a subset of active children. METHODS: We recruited students from 10 public primary schools and obtained repeated measures of BMI, waist circumference, and aerobic fitness over 30 months. Aerobic fitness was measured with the Andersen test. We objectively measured physical activity behaviour with accelerometers and classified children as 'physically active' when they achieved ≥ 60 min of moderate-to-vigorous PA per day (guideline concordance). Univariate trajectories of BMI, waist circumference, and aerobic fitness were calculated for all children, and we constructed a multi-trajectory model comprising all outcomes in the subgroup of physically active children. The construct validity of all models was investigated by examining for between-group differences in cardiovascular disease risk factors obtained from fasting blood samples. RESULTS: Data from 1208 children (53% female) with a mean (SD) age of 8.4 (1.4) years were included. The univariate trajectory models identified three distinct trajectories for BMI, waist circumference, and aerobic fitness. The multi-trajectory model classified 9.1% of physically active children as following an 'overweight/obese/low fitness' trajectory. There were moderate-to-large differences in cardiovascular risk factors between all trajectory groups (p < 0.001; d = 0.4-1.20). CONCLUSION: We identified distinct developmental trajectories of BMI, waist circumference, and aerobic fitness in children. Nearly one in 10 children who met PA guideline recommendations followed an unfavourable health trajectory. Health-related PA recommendations may be insufficient for some children.

Modifying bowling kinematics in cricket pace bowlers with exercise-based injury prevention: A cluster-randomised controlled trial.

OBJECTIVES: Undesirable bowling kinematics can increase the risk of low back injury. This study investigated if an exercise-based injury prevention program (IPP) could modify bowling kinematics in community-level adolescent pace bowlers. DESIGN: Cluster-randomised controlled trial. METHODS: Pace bowlers from eight cricket organisations were cluster-randomised into an intervention or control group. At baseline and follow-up sessions biomechanical bowling data were collected. Between sessions, the intervention group completed an eight-week IPP while the control continued their normal cricket activity. Treatment effects (95% CI) were estimated with linear mixed models. RESULTS: There were significant treatment effects favouring the intervention group for shoulder counter-rotation (-3.8°; -7.2° to -0.3°) and lateral trunk flexion relative to the pelvis (-2.2°; -4.0° to -0.5°). Shoulder counter-rotation also increased in the control group by 2.2° (Cohen's d=0.22). There were no effects of the intervention on: lateral trunk flexion at front foot contact (FFC) (1.2°; -2.5° to 4.8°), lateral trunk flexion at ball release (BR) (-0.5°; -3.0° to 2.0°), pelvis rotation at FFC (0.9°; -4.0° to 2.2°), pelvis rotation at BR (-1.1°; -5.7° to 3.6°), front hip angle at FFC (1.6°; -3.6° to 6.7°), front hip angle at BR (-1.6°; -5.0° to 1.9°), front knee angle at FFC (-1.1°; -4.5° to 2.3°), front knee angle at BR (1.7°; -5.6° to 9.1°), or ball velocity (1.1kmh-1; -7.5kmh-1 to 9.7kmh-1). CONCLUSIONS: The IPP maintained shoulder counter-rotation and lateral trunk flexion relative to the pelvis in the intervention group and this could attenuate injury risk. No treatment effects were observed for lower-limb kinematics.