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Study Design: Prospective study., Objective: To compare the burden between chronic nonspecific low back pain (LBP) and axial spondyloarthropathy (SpA)., Summary of Background Data: Chronic nonspecific LBP and SpA are two debilitating yet different chronic musculoskeletal disorders. To compare their burden, propensity score matching is used to control for potential confounders and match the study subjects., Materials and Methods: Two prospectively collected cohorts of LBP (n=269) and SpA (n=218) patients were studied. Outcomes included current LBP, 36-item Short Form Questionnaire, Oswestry Disability Index, EuroQol 5-dimension 5-level Questionnaire, and EuroQol Visual Analog Scale. With the inherent differences between the two types of patients, propensity score matching was performed for comparing the two groups. Baseline covariates of age, sex, education level, occupation, smoking, and drinking history were selected for the estimation of propensity scores for each subject with the logistic regression model. Significant independent variables for the outcome of current back pain were included in the multivariate logistic regressions., Results: A total of 127 matched pairs were identified, with 254 patients. In the matched cohort, more patients with chronic LBP had current back pain (95.3%) as compared with SpA (71.7%). Patients with SpA were younger ( P <0.001), with more males ( P <0.001), and better educated ( P =0.001). There was less current back pain and higher nonsteroidal anti-inflammatory drug use ( P <0.001). Most SpA patients had lower Oswestry Disability Index than LBP patients and with low disease activity. Patients with LBP had worse outcome scores as compared with SpA patients given the same Visual Analog Scale. LBP patients had 8.6 times the odds (95% CI: 3.341-20.671; P <0.001) of experiencing current back pain compared with SpA patients., Conclusions: The disease activity of SpA patients is well controlled. However, patients with chronic LBP have worse pain severity, disability, and health-related quality of life. This has implications on resource utilization and the necessity of advancing LBP understanding and management., Level of Evidence: Type I prognostic study., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)

Study Design: RAND/UCLA Appropriateness Method (RUAM) applied to chiropractic manipulation for patients with chronic low-back pain (CLBP) and chronic neck pain (CNP)., Objective: Determine the rate of appropriate care provided by US chiropractors., Summary of Background Data: Spinal manipulation has been shown effective for CLBP and CNP but may not be appropriate for all patients with these conditions., Methods: Ratings of the appropriateness of spinal and cervical manipulation previously developed by two RUAM expert panels were applied to data abstracted from random samples of patient charts from chiropractors in six US regions to determine the appropriateness of manipulation for each patient., Results: Of 125 chiropractors sampled, 89 provided charts that could be abstracted. Of the 2128 charts received, 1054 were abstracted. Charts received but not abstracted included 460 that were unusable (e.g., illegible), and 555 did not have CLBP or CNP. Across the abstracted charts 72% had CLBP, 57% had CNP, and 29% had both; 84% of patients with CLBP and 86% with CNP received manipulation. Patients with CLBP who had minor neurologic findings, sciatic nerve irritation, or no joint dysfunction were significantly less likely to receive manipulation. Patients with CNP who had substantial trauma etiology, no joint dysfunction, or no radiographs were significantly less likely to receive manipulation. Most manipulation for CLBP (64%) was appropriate and most manipulation for CNP (93%) was for patients where appropriateness was uncertain or equivocal. The proportions of patients receiving inappropriate manipulation for either condition were low (1%-3%) as were the numbers of patients presenting to these chiropractors for which manipulation was inappropriate., Conclusion: Chiropractors in this US sample tend to provide manipulation to very few patients with CLBP or CNP for which it is inappropriate. However, more research is needed to determine which patients with CNP benefit from manipulation.Level of Evidence: 4., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Study Design: Cross-sectional study., Objective: The aim of this study was to assess the structural validity of the Brazilian version of the Neck Disability Index (NDI) in patients with chronic neck pain., Summary of Background Data: NDI is widely used in clinical and scientific contexts, although its structure has not been evaluated in the Brazilian version., Methods: Native Brazilian Portuguese speakers, aged ≥18 years, with neck pain complaint of at least 3 months, and minimal pain rating of 3 points at rest or during neck movements were included. Exploratory factorial analysis (EFA) and confirmatory factorial analysis (CFA) were used. In EFA, the adequacy of the model was assessed using Bartlett test of sphericity and Kaiser-Meyer-Olkin test. In CFA, the goodness-of-fit was assessed by the indices: root mean square error of approximation with 90% of confidence interval, comparative fit index, Tucker-Lewis Index, standardized root mean square residual, and χ2/degree of freedom. Akaike information criterion (AIC) and Bayesian information criterion (BIC) were considered to compare the models., Results: Two hundred fifty-four participants with chronic neck pain were included. The NDI model with one domain and five items presented the most adequate goodness-of-fit indexes and the lowest values of AIC and BIC, when compared with models with one domain and 10, eight, or seven items, and with the model with two domains and 10 items., Conclusion: In the Brazilian context, the NDI version with one domain and five items (personal care, concentration, work, driving, and recreation) presents the best structure according to the factorial analysis.Level of Evidence: 5., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Study Design: Cultural adaptation and psychometric analysis., Objective: This study determined the test-retest reliability, acceptability, internal consistency, divergent validity of the Yoruba pain self-efficacy questionnaire (PSEQ-Y). It also examined the ceiling and floor effects and the small detectable change (SDC) of the PSEQ-Y among patients with chronic low back pain (LBP)., Summary of Background Data: There are various indigenous language translations of the PSEQ and none adapted to African language. However, translations of the PSEQ into Nigerian languages are not readily available., Methods: The validity testing phase of the study involved 131 patients with LBP, while 83 patients with LBP took part in the reliability phase. Following the Beaton recommendation for cultural adaptation of instruments, the PSEQ was adapted into the Yoruba language. The psychometric properties of the PSEQ-Y determined comprised: internal consistency, divergent validity, test-retest reliability, and SDC., Results: The mean age of the participants was 52.96 ± 17.3 years. The PSEQ-Y did not correlate with the Yoruba version of Visual Analogue Scale (VAS-Y) scores (r = -0.05; P = 0.59). The values for the internal consistency and the test-retest reliability of the PSEQ-Y were 0.79 and 0.86, with the 95% confidence interval of the test-retest reliability ranging between 0.82 and 0.90. The standard error of measurement (SEM) and the SDC of the PSEQ-Y were 1.2 and 3.3, respectively. The PSEQ-Y had no floor or ceiling effect, as none of the respondents scored either the minimal or maximal scores., Conclusion: This is the first study in Nigeria to culturally adapt PSEQ. The PSEQ-Y showed adequate psychometric properties similar to existing versions. Therefore, the tool can be used to assess pain self-efficacy in clinical and research settings and help to improve the health outcomes of patients chronic LBP.Level of Evidence: 3., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Study Design: Individual participant data (IPD) meta-analysis., Objective: The aim of this study was to identify which participant characteristics moderate the effect of spinal manipulative therapy (SMT) on pain and functioning in chronic LBP., Summary of Background: The effects of SMT are comparable to other interventions recommended in guidelines for chronic low back pain (LBP); however, it is unclear which patients are more likely to benefit from SMT compared to other therapies., Methods: IPD were requested from randomized controlled trials (RCTs) examining the effect of SMT in adults with chronic LBP for pain and function compared to various other therapies (stratified by comparison). Potential patient moderators (n = 23) were a priori based on their clinical relevance. We investigated each moderator using a one-stage approach with IPD and investigated this interaction with the intervention for each time point (1, 3, 6, and 12 months)., Results: We received IPD from 21 of 46 RCTs (n = 4223). The majority (12 RCTs, n = 2249) compared SMT to recommended interventions. The duration of LBP, baseline pain (confirmatory), smoking, and previous exposure to SMT (exploratory) had a small moderating effect across outcomes and follow-up points; these estimates did not represent minimally relevant differences in effects; for example, patients with <1 year of LBP demonstrated more positive point estimates for SMT versus recommended therapy for the outcome pain (mean differences ranged from 4.97 (95% confidence interval, CI: -3.20 to 13.13) at 3 months, 10.76 (95% CI: 1.06 to 20.47) at 6 months to 5.26 (95% CI: -2.92 to 13.44) at 12 months in patients with over a year LBP. No other moderators demonstrated a consistent pattern across time and outcomes. Few moderator analyses were conducted for the other comparisons because of too few data., Conclusion: We did not identify any moderators that enable clinicians to identify which patients are likely to benefit more from SMT compared to other treatments.Level of Evidence: 2., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc.)

Study Design: Translation, cross-cultural adaptation, and psychometric testing., Objective: To translate, cross-culturally adapt, and validate the Numerical Pain Rating Scale (NPRS) and the Global Rating of Change Scale (GRCS) into Hausa language., Summary of Background Data: The NPRS and GRCS are commonly used patient-reported outcome measures in a variety of pain-related conditions including low back pain. To date, neither the NPRS nor GROC are available in Hausa language., Methods: The Hausa versions of the NPRS (NPRS-H) and GRCS (GRCS-H) were developed using recommended guidelines. The final versions were then administered to 120 patients with chronic low back pain to access their psychometric properties. Reliability assessment included calculations of intraclass correlation coefficient (ICC) and minimal detectable change among the stable group. Construct validity and concurrent validity were assessed using the Spearman rank correlation coefficient. Internal responsiveness was assessed using mean change scores, standardized effect size, and standard response mean. Receiver operating characteristic curves were plotted to determine the external responsiveness of the NPRS-H using the area under the curve, and minimal important change for small, medium, and large improvements. Outcome measures consisted of the Visual Analogue Scale for pain and Oswestry Disability Index., Results: The NPRS-H and GRCS-H were successfully developed. High test-retest reliability was demonstrated for both the NPRS-H (ICC = 0.95) and GRCS-H (ICC = 0.94) with minimal detectable change points of 1.0 and 1.2 respectively. The scales showed moderate to strong correlation with the Visual Analogue Scale for pain and Oswestry Disability Index. The mean change of the NPRS-H scores correlated moderately with the GRCS-H. Both scales demonstrated good internal responsiveness. External responsiveness of the NPRS-H was demonstrated at three levels with area under the curve  = 0.875 to 0.972, and minimal important change  = 2.5 to 3.5., Conclusions: The NPRS and GRCS were successfully adapted into Hausa language with acceptable reliability, validity, and responsiveness. These measures are appropriate for clinical and research use among Hausa-speaking patients., Level of Evidence: 2.

Study Design: Cross-sectional study., Objective: To investigate the equivalence of electronic and paper version of self-report questionnaires for the assessment of disability, pain, fear of movement, depression, and physical activity of patients with chronic low back pain (LBP)., Summary of Background Data: Paper and electronic versions of self-report questionnaires are commonly used for assessment of patients with LBP. However, the equivalence of self-report questionnaires commonly used for assessment of patients with chronic LBP remains unclear., Methods: Seventy-nine individuals with chronic LBP seeking physiotherapy care were recruited. Participants attended the clinic twice with an interval of 1 week and completed the self-reported questionnaires in a random order. The following questionnaires were administered: Roland Morris Disability Questionnaire (RMDQ); 11-point numerical rating scale (NRS); Tampa Scale for Kinesiophobia (TSK); Center for Epidemiological Studies-Depression (CES-D), and Baecke Habitual Physical Activity Questionnaire (BPAQ). To investigate the equivalence between the two questionnaire versions, intraclass correlation coefficient with 95% confidence interval and Bland-Altman plotting was used., Results: The paper and electronic versions of the RMDQ, TSK, and CES-D showed good reliability and the showed moderate reliability. In contrast, the NRS showed poor reliability between the electronic and paper versions., Conclusion: Our findings support that the electronic version of the RMDQ, TSK, CES-D, and BPAQ can be administered in clinical and research settings for assessment of patients with chronic LBP. Nevertheless, electronic version of the NRS for assessment of pain intensity should not be used interchangeably in clinical practice in patients with chronic LBP., Level of Evidence: 3.

Study Design: Retrospective cohort study., Objective: To (1) confirm validity of Patient-Reported Outcomes Measurement Information System (PROMIS) physical function and pain interference computer-adaptive tests (CATs) and (2) assess the validity of PROMIS Global Health (GH) and five additional PROMIS CATs: social role satisfaction, fatigue, anxiety, depression, and sleep disturbance in a population of patients with chronic low back pain (cLBP) who completed a 3-month Interdisciplinary Pain Program (IPP)., Summary of Background Data: Recent recommendations for assessing outcomes in patients with cLBP have included PROMIS scales; however, there is a need for further evaluation, and PROMIS GH has not been studied in this population., Methods: The study cohort included patients with cLBP who completed the entirety of a 3-month IPP between August 2016 and December 2018. Patient-reported outcome measures (PROMs) were analyzed before the start of the IPP and at graduation. Convergent and discriminant validity were evaluated using Pearson correlation coefficients. Known groups' validity assessed the change in PROMIS scores stratified by improvement on the Modified LBP Disability Questionnaire. Responsiveness was evaluated with standardized response means based on global impression of change., Results: IPP was completed by 217 patients (67.7% women, age 53.8 ± 12.8). Convergent validity was supported (P < 0.01 for all pairwise PROMs comparisons). All PROMs improved significantly by graduation, with the largest improvement for PROMIS pain interference, physical function, social role satisfaction, and Modified LBP Disability Questionnaire. Known groups' validity demonstrated the greatest change on PROMIS physical function, social role satisfaction, pain interference, and depression. Responsiveness was supported for all PROMs in 170 (78.3%) patients who indicated at least minimal improvement (standardized response means 0.43-1.06)., Conclusion: Our study provides support of PROMIS CATs, highlights the importance of including other meaningful outcome measures, such as social role satisfaction, and provides the first validation of PROMIS GH, in patients with cLBP. PROMs collection can be streamlined through the use of PROMIS CATs which offer advantages over legacy measures., Level of Evidence: 3.

Study Design: Prospective cohort study., Objective: To analyze responsiveness and minimal clinically important change (MCIC) of the US National Institutes of Health (NIH) minimal dataset for chronic low back pain (CLBP)., Summary of Background Data: The NIH minimal dataset is a 40-item questionnaire developed to increase use of standardized definitions and measures for CLBP. Longitudinal validity of the total minimal dataset and the subscale Impact Stratification are unknown., Methods: Total outcome scores on the NIH minimal dataset, Dutch Language Version, were calculated ranging from 0 to 100 points with higher scores representing worse functioning. Responsiveness and MCIC were determined with an anchor-based method, calculating the area under the receiver operating characteristics (ROC) curve (AUC) and by determining the optimal cut-off point. Smallest detectable change (SDC) was calculated as a parameter of measurement error., Results: In total 223 patients with CLBP were included. Mean total score on the NIH minimal dataset was 44 ± 14 points at baseline. The total outcome score was responsive to change with an AUC of 0.84. MCIC was 14 points with a sensitivity of 72% and specificity 82%, and SDC was 23 points. Mean total score on Impact Stratification (scale 8-50) was 34.4 ± 7.4 points at baseline, with an AUC of 0.91, an MCIC of 7.5 with a sensitivity 96% of and specificity of 78%, and an SDC of 14 points., Conclusion: The longitudinal validity of the NIH minimal dataset is adequate. An improvement of 14 points in total outcome score and 7.5 points in Impact Stratification can be interpreted as clinically important in individual patients. However, MCIC depends on baseline values and the method that is chosen to determine the optimal cut-off point. Furthermore, measurement error is larger than the MCIC. This means that individual change scores should be interpreted with caution., Level of Evidence: 2.

Study Design: Controlled clinical trial study., Objective: This study aimed to evaluate the effect of core stabilization exercise program (CSEP) on trunk-pelvis kinematics during gait in non-specific chronic low back pain (NCLBP)., Summary of Background Data: NCLBP is a major public burden with variety of dysfunction including gait variability., Methods: Thirty participants (15 NCLBP and 15 healthy) were included in this study via the convenience sampling method. NCLBP group were intervened via the 16 sessions CSEP 3 days for 6 weeks and trunk-pelvis kinematics (angular displacement, waveform pattern [CVp], and offset variability [CVo]) during gait, pain, disability were evaluated before and after the intervention., Results: No significant differences in displacement and CVo in three planes were found between NCLBP and healthy groups. Independent t test was revealed that significant differences in CVp in the sagittal, frontal, and transverse planes were found between healthy and NCLBP in pre intervention. No significant changes in displacement and CVo were found as the result of intervention in NCLBP. Pain and disability decreased significantly after intervention. Paired t test revealed that the CSEP increased the frontal (P = 0.04) and transverse planes (P = 0.02) pattern variability significantly. However, there was a significant difference between groups in the sagittal plane CVp after intervention (sagittal plane CVp in healthy vs. NCLBP in post-CSE: mean difference = 14.1; P = 0.04)., Conclusion: Considering the role of the deep trunk muscles in gait, and their common deconditioning in CLBP, a CSEP intervention may increase trunk-pelvis kinematic pattern variability. These results suggest CSEP may specifically increase transverse and frontal plane variability, indicating improved motor pattern replication through this movement planes., Level of Evidence: 2.

Study Design: A retrospective chart review., Objective: The aim of this study was to address and characterize the differences between pain relief obtained from the "trial" versus permanent stimulator in the acute postoperative period (less than 6 weeks)., Summary of Background Data: After a short stimulator trial (typically less than 7 days), patients who report at least a 50% relief are set up for permanent spinal cord stimulator (SCS) placement. The literature has shown that a subset of patients develop tolerance to these stimulating therapies, often resulting in reduced efficacy of symptom relief as early as 2 years post-permanent implantation., Methods: Between the years of 2013 and 2017, 241 patient charts who underwent a successful trial and had a subsequent permanent SCS placed by a fellowship-trained surgeon through an open incision were reviewed. For each patient, demographic information, numerical rating system (NRS) pain scores, Oswestry Disability Index (ODI) scores, and opioid medication usage were recorded and stratified by time-period (before trial, after trial and before permanent placement, and after permanent SCS placement)., Results: Of the 100 included patients, 60 were female; 60 patients had previous failed lumbar surgery (53%). Placement of trial stimulator (median = 4) decreased pain scores significantly more than permanent spinal cord stimulator did (median = 2) (P = 0.00). No significant difference was seen in ODI score difference between trial and initial scores (median = 4) and final and initial scores (median = 6) (P = 0.64). Finally, a significantly higher decrease in pain medication usage was seen after trial initiation (median = 0) versus after permanent spinal cord stimulator placement (median = 0) (P = 0.028). Twenty-two patients (22%) had reported complications, with 15 complaining of prolonged surgical site pain., Conclusion: Discrepancies observed in symptom alleviation between percutaneous trials and permanent placement in the acute 6-week postop period can have a significant effect on patient perceived outcomes. Understanding these issues will help in providing preoperative counseling and managing postoperative expectations., Level of Evidence: 4.

Study Design: Systematic review., Objective: To investigate the effects of Kinesio Taping (KT) in patients with nonspecific low back pain., Summary of Background Data: KT is widely used in patients with low back pain., Methods: We conducted searches on PubMed, EMBASE, PEDro, SciELO, and LILACS up to February 26, 2018. We included only randomized controlled trials (RCTs) in adults with chronic nonspecific low back pain that compared KT to no intervention or placebo as well as RCTs that compared KT combined with exercise against exercise alone. The methodological quality and statistical reporting of the eligible trials were measured by the 11-item PEDro scale. The quality of the evidence was assessed using the GRADE classification. We considered pain intensity and disability as the primary outcomes. Whenever possible, the data were pooled through meta-analysis., Results: We identified 11 RCTs for this systematic review (pooled n = 743). Two clinical trials (pooled n = 100) compared KT to no intervention at the short-term follow-up. Four studies compared KT to placebo (pooled n = 287) at short-term follow-up and two trials (pooled n = 100) compared KT to placebo at intermediate-term follow-up. Five trials (pooled n = 296) compared KT combined with exercises or electrotherapy to exercises or spinal manipulation alone. No statistically significant difference was found for most comparisons., Conclusion: Very low to moderate quality evidence shows that KT was no better than any other intervention for most the outcomes assessed in patients with chronic nonspecific low back pain. We found no evidence to support the use of KT in clinical practice for patients with chronic nonspecific low back pain., Level of Evidence: 1.

Study Design: Psychometric test of the cross-cultural adaptation the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) in low back pain (LBP) patients., Objective: To investigate the agreement, responsiveness, and minimal important change (MIC) of the simplified Chinese version of the JOABPEQ in LBP patients., Summary of Background Data: The factor structure, internal consistency, test-retest reliability, validity, floor and ceiling effect of simplified Chinese JOABPEQ have been tested, while the agreement, responsiveness, and MIC were required., Methods: The agreement, responsiveness, and MIC of the simplified Chinese version were assessed by completing the Chinese JOABPEQ twice. Agreement was tested with Bland-Altman plot. Responsiveness was operationalized using receiver operating characteristic analyses. The anchor-based method was used to calculate MIC., Results: One hundred sixty-two of 184 patients returned to finish the booklet twice were available for analysis (response rate: 88.0%). While the responsiveness, the area under the curves of each subscale were ranged from 0.746 to 0.875, which meant a good responsiveness. While the MIC (MIC%) of simplified Chinese JOABPEQ was 19.28 (44.98%) for Q1 Low back pain, 15.20 (24.13%) for Q2 Lumbar function, 15.79 (22.76%) for Q3 Walking ability, 9.58 (19.86%) for Q4 Social life function, 7.33 (17.28%) for Q5 Mental health. While compared with the MIC, only the Q3 Walking ability had a positive rating for agreement in the Bland-Altman plot., Conclusion: The simplified Chinese JOABPEQ has positive agreement of Q3 Walk ability and acceptable to excellent responsiveness of all the subscales. The MICs for subscales of the simplified Chinese JOABPEQ ranged from 7.33 to 19.28 points., Level of Evidence: 3.

Study Design: A cross-sectional study., Objective: This study was designed to analyze the relationship between the presence and severity of depression and low back pain (LBP) in a representative sample of the general population using a self-report screening questionnaire for depression., Summary of Background Data: There is increasing evidence supporting an association between depression and LBP. However, the degree of the association between these two conditions in the general population is poorly understood., Methods: Health surveys and examinations were conducted on a nationally representative sample (n = 7550) of Koreans. LBP status was determined by a simple survey response concerning LBP >30 days during the past 3 months. Depression was defined as individuals with a total score >10 on the Patient Health Questionnaire (PHQ)-9 survey. The severity of depression was categorized as none (0-4), mild (5-9), moderate (10-14), moderately severe (15-19), and severe (20-27) according to PHQ-9 score. Data regarding demographics, socioeconomic history, and comorbid health conditions were used to analyze adjusted, weighted logistic regression models., Results: In the Korean population, the prevalence of depression was significantly greater in individuals with LBP (20.3%) than in those without LBP (4.5%). On multivariate logistic regression analysis, the presence of depression was significantly associated with LBP (adjusted odd ratio [aOR]: 3.93, P < 0.001). The risk of LBP increased with increasing severity of depression as follows: severe depression (aOR: 9.28, P < 0.001), moderately severe depression (aOR: 3.24, P = 0.001), moderate depression (aOR: 4.97, P < 0.001), and mild depression (aOR: 2.48, P < 0.001)., Conclusion: Depression is more common in patients with LBP among Koreans. The presence of depression was significantly associated with LBP, especially in severely depressed individuals., Level of Evidence: 3.

Study Design: Translation and cultural adaptation of the National Institutes of Health (NIH) Task Force's minimal dataset., Objective: The purpose of this study was to evaluate validity and reliability of the Farsi version of NIH Task Force's recommended multidimensional minimal dataset for research on chronic low back pain (CLBP)., Summary of Background Data: Considering the high treatment cost of CLBP and its increasing prevalence, NIH Pain Consortium developed research standards (including recommendations for definitions, a minimum dataset, and outcomes' report) for studies regarding CLBP. Application of these recommendations could standardize research and improve comparability of different studies in CLBP., Methods: This study has three phases: translation of dataset into Farsi and its cultural adaptation, assessment of pre-final version of dataset's comprehensibility via a pilot study, and investigation of the reliability and validity of final version of translated dataset. Subjects were 250 patients with CLBP. Test-retest reliability, content validity, and convergent validity (correlations among different dimensions of dataset and Farsi versions of Oswestry Disability Index, Roland Morris Disability Questionnaire, Fear-Avoidance Belief Questionnaire, and Beck Depression Inventory-II) were assessed., Results: The Farsi version demonstrated good/excellent convergent validity (the correlation coefficient between impact dimension and ODI was r = 0.75 [P < 0.001], between impact dimension and Roland-Morris Disability Questionnaire was r = 0.80 [P < 0.001], and between psychological dimension and BDI was r = 0.62 [P < 0.001]). The test-retest reliability was also strong (intraclass correlation coefficient value ranged between 0.70 and 0.95) and the internal consistency was good/excellent (Chronbach's alpha coefficients' value for two main dimensions including impact dimension and psychological dimension were 0.91 and 0.82 [P < 0.001], respectively). In addition, its face validity and content validity were acceptable., Conclusion: The Farsi version of minimal dataset for research on CLBP is a reliable and valid instrument for data gathering in patients with CLBP. This minimum dataset can be a step toward standardization of research regarding CLBP., Level of Evidence: 3.

MINI: The authors wanted to determine which existing primary-care low back pain stratification schema is associated with distinct subpopulations. Initial stratification by DMPP identified potentially distinct epidemiological groups. DMPP stratification resulted in discrimination beyond that provided by disability or chronicity risk stratification alone., Study Design: A cross-sectional study of Canadian patients suffering from low back pain (LBP) seeking primary care., Objective: The aim of this study was to determine which existing primary care LBP stratification schema is associated with distinct subpopulations as characterized by easily identifiable primary epidemiological factors., Summary of Background Data: LBP is among the most frequent reasons for visits to primary care physicians and a leading cause of years lived with disability. In an effort to improve treatment response/outcomes in LBP primary care, different classification systems have been proposed in an effort to provide more tailored treatment with the intent of improving outcomes. Group-specific risk factors and underlying etiology might suggest a need for, or inform, changes to treatment approaches to optimize LBP outcomes., Methods: Stratification by dominant mechanical pain patterns; chronicity risk; disability severity. Multinomial logistic regression was used to identify the system showing greatest variability in associations with age, sex, obesity, and comorbidity. Once identified, the remaining schemas were incorporated into the model., Results: N = 970; mean age: 50 years (range: 18-93); 56% female. Stratification by pain pattern revealed greater variability. Adjusted analysis: Increasing age was associated with greater odds of intermittent, extension-based back- or leg-dominant pain [odds ratio (OR): 1.02 and 1.06; P < 0.01]; being male with leg-dominant pain (ORs > 2; P < 0.01). Overweight/obesity was associated with extension-based leg-dominant pain (OR = 2.6; P < 0.02) and increasing comorbidity with extension-based back-dominant pain (OR = 1.3; P < 0.01). Severe disability was associated only with constant leg pain (OR = 3.9; P < 0.01), and high chronicity risk with extension-based leg-dominant pain (OR = 0.4; P = 0.03)., Conclusion: Dominant mechanical symptom stratification resulted in further discrimination of an epidemiologically distinct and a large subgroup of LBP patients not identified by disability or chronicity risk stratification alone. Findings suggest a need for primary care initiated multidimensional stratification in chronic LBP., Level of Evidence: 3.

Study Design: Psychometric testing of the Persian version of Pain Anxiety Symptom Scale 20., Objective: The aim of this study was to assess the reliability and construct validity of the PASS-20 in nonspecific chronic low back pain (LBP) patients., Summary of Background Data: The PASS-20 is a self-report questionnaire that assesses pain-related anxiety. The Psychometric properties of this instrument have not been assessed in Persian-speaking chronic LBP patients., Methods: One hundred and sixty participants with chronic LBP completed the Persian version of PASS-20, Tampa Scale of Kinesiophobia (TSK), Fear-Avoidance Beliefs Questionnaire (FABQ), Pain Catastrophizing Scale (PCS), trait form of the State-Trait Anxiety (STAI-T), Oswestry Low Back Pain Disability Index (ODI), Beck Depression Inventory (BDI-II), and Visual Analogue Scale (VAS). To evaluate test-retest reliability, 60 patients filled out the PASS-20, 6 to 8 days after the first visit. Test-retest reliability (intraclass correlation coefficient [ICC], standard error of measurement [SEM], and minimal detectable change [MDC]), internal consistency, dimensionality, and construct validity were examined., Results: The ICCs of the PASS-20 subscales and total score ranged from 0.71 to 0.8. The SEMs for PASS-20 total score was 7.29 and for the subscales ranged from 2.43 to 2.98. The MDC for the total score was 20.14 and for the subscales ranged from 6.71 to 8.23. The Cronbach alpha values for the subscales and total score ranged from 0.70 to 0.91. Significant positive correlations were found between the PASS-20 total score and PCS, TSK, FABQ, ODI, BDI, STAI-T, and pain intensity., Conclusion: The Persian version of the PASS-20 showed acceptable psychometric properties for the assessment of pain-related anxiety in Persian-speaking patients with chronic LBP., Level of Evidence: 3.

Study Design: A retrospective study., Objective: The aim of this study was to investigate the feasibility and applicability of support vector machine (SVM) algorithm in classifying patients with LBP who would obtain satisfactory or unsatisfactory progress after the functional restoration rehabilitation program., Summary of Background Data: Dynamic surface electromyography (SEMG) topography has demonstrated the potential use in predicting the prognosis of functional restoration rehabilitation for patients with low back pain (LBP). However, processing from raw SEMG topography to make prediction is not easy to clinicians., Methods: A total of 30 patients with nonspecific LBP were recruited and divided into "responding" and "non-responding" group according to the change of Visual analog pain rating scale and Oswestry Disability Index. Each patient received a 12-week functional restoration rehabilitation program. A normal database was calculated from a control group from 48 healthy participants. Root-mean-square difference (RMSD) was extracted from the recorded dynamic SEMG topography during symmetrical and asymmetrical trunk-movement. SVM and cross-validation were applied to the prediction based on the optimized features selected by the sequential floating forward selection (SFFS) algorithm., Results: RMSD feature parameters following rehabilitation in the "responding" group showed a significant difference (P < 0.05) with the one in the "nonresponding" group. The SVM classifier with Quadratic kernel based on SFFS-selected features showed the best prediction performance (accuracy: 96.67%, sensitivity: 100%, specificity: 93.75%, average area under curve [AUC]: 0.8925) comparing with linear kernel (accuracy: 80.00%, sensitivity: 85.71%, specificity: 75.00%, average AUC: 0.7825), polynomial kernel (accuracy: 93.33%, sensitivity: 92.86%, specificity: 93.75%, average AUC: 0.9675), and radial basis function (RBF) kernel (accuracy: 86.67%, sensitivity: 85.71%, specificity: 87.50%, average AUC: 0.7900)., Conclusion: The use of SVM-based classifier of SEMG topography can be applied to identify the patient responding to functional restoration rehabilitation, which will help the healthcare worker to improve the efficiency of LBP rehabilitation., Level of Evidence: 3.

Study Design: Validation study with cross-sectional and longitudinal measurements., Objective: To translate the US National Institutes of Health (NIH)-minimal dataset for clinical research on chronic low back pain into the Dutch language and to test its validity and reliability among people with chronic low back pain., Summary of Background Data: The NIH developed a minimal dataset to encourage more complete and consistent reporting of clinical research and to be able to compare studies across countries in patients with low back pain. In the Netherlands, the NIH-minimal dataset has not been translated before and measurement properties are unknown., Methods: Cross-cultural validity was tested by a formal forward-backward translation. Structural validity was tested with exploratory factor analyses (comparative fit index, Tucker-Lewis index, and root mean square error of approximation). Hypothesis testing was performed to compare subscales of the NIH dataset with the Pain Disability Index and the EurQol-5D (Pearson correlation coefficients). Internal consistency was tested with Cronbach α and test-retest reliability at 2 weeks was calculated in a subsample of patients with Intraclass Correlation Coefficients and weighted Kappa (κω)., Results: In total, 452 patients were included of which 52 were included for the test-retest study., Validity: factor analysis for structural validity pointed into the direction of a seven-factor model (Cronbach α = 0.78). Factors and total score of the NIH-minimal dataset showed fair to good correlations with Pain Disability Index (r = 0.43-0.70) and EuroQol-5D (r = -0.41 to -0.64). Reliability: test-retest reliability per item showed substantial agreement (κω=0.65). Test-retest reliability per factor was moderate to good (Intraclass Correlation Coefficient = 0.71)., Conclusion: The Dutch language version measurement properties of the NIH-minimal were satisfactory., Level of Evidence: N/A.

Study Design: A significant number of lumbar postsurgical patients continue to suffer persistent pain and limited function and are termed to have "Failed back surgery syndrome" (FBSS). This review evaluates clinical trial data for the treatment of FBSS patients., Objective: Using an evidence-based approach to evaluate FBSS treatments will assist clinicians in choosing the most effective options for FBSS patients. Furthermore, reducing the utilization of less effective therapies may result in substantial financial savings for this patient population., Summary of Background Data: Treatments for FBSS may be generally categorized as physical therapy and exercise, medications, interventional procedures, neuromodulation, and reoperation. Careful review and classification of the level of evidence available for each category of treatment for FBSS patients will help guide clinical decision-making., Methods: A literature review was performed for FBSS treatments. The publications were arranged hierarchically according to the North American Spine Society's guidelines as randomized controlled trials (RCTs), prospective studies, retrospective chart, and systematic reviews. Book chapters, nonsystematic reviews, and expert opinions were excluded. The review focused on studies with at least 20 FBSS patients and 6-month follow-up., Results: Evidence is weak for medications and reoperation, but strong for active exercise and interventional procedures such as adhesiolysis. The strongest evidence for long-term treatment is for spinal cord stimulation (SCS), showing favorable Level I RCT results compared with conventional medical management and reoperation. In addition, high-frequency SCS at 10 kHz has demonstrated superiority over traditional, low-frequency SCS for treating low back and leg pain in a recent Level I RCT., Conclusion: Clinicians may increasingly utilize levels of evidence during their evaluation of each FBSS patient to render the best therapeutic plan, likely resulting in improved long-term pain control and reducing costs by avoiding less effective modalities. New directions in SCS show promising results for the treatment of FBSS., Level of Evidence: 1.

Study Design: Topic overview., Objective: To describe the varied etiologies resulting in chronic spinal pain and review the current available evidence for treatments., Summary of Background Data: Chronic pain conditions, especially those that affect the axial back and radiate to the extremities, affect a large population. This results in pronounced disability and a high socioeconomic burden. Our understanding of the underlying mechanisms for chronic pain is limited. This prevents a comprehensive diagnostic approach. Evidence from high-level clinical trials supporting treatments for chronic spinal pain is also limited., Methods: Articles were identified through PubMed searches or already known to the author. The literature was reviewed and summarized, indicating the strength of evidence available for many treatment modalities., Results: There are very few studies published that evaluate behavioral modifications for chronic spinal pain and only one long-term study investigating chronic pharmacological treatments. The data on the success of spinal surgeries to relieve chronic spinal pain suggest an unacceptably high failure rate. The best evidence (Level I) currently available suggests that spinal cord stimulation is a safe, effective, and durable treatment for chronic spinal pain. Recent clinical data support further investigation of new innovations and earlier therapeutic consideration of currently employed approaches., Conclusion: Currently, physicians are limited in the practice of evidence-based medicine regarding chronic spinal pain treatments due to both the paucity of data available and an inconsistent diagnostic nomenclature. The introduction of new neurostimulation modalities is promising but requires better characterization through ongoing prospective clinical investigation., Level of Evidence: 5.

Study Design: A review of the literature evaluating clinical trials of chronic back pain., Objective: To assist physicians in assessing the quality of clinical trial data to make the most informed treatment decisions., Summary of Background Data: Chronic pain is a tremendous public health issue, affecting close to 100 million adults in the United States, and costs the American people billions of dollars. One traditional treatment approach, the long-term use of opiate medications, has recently come under intense scrutiny for problems with complications, diversion, abuse, addiction, and lack of efficacy. In addition, the Centers for Disease Control and Prevention has recognized that overprescribing opiates has enabled an overdose crisis, and written guidelines that are intended to limit their use. It is for this reason that physicians must have a comprehensive understanding of the range of drug-free alternative therapies available and have the tools needed to rigorously evaluate the chronic pain literature so they can make appropriate treatment decisions., Methods: An evaluation of how clinical trials are designed and ranked, outcome measures, and costs for a variety of therapies is necessary to determine which treatment option is the most efficacious for an individual patient., Results: Clinical trial data demonstrate that spinal cord stimulation (SCS) is a safe and effective treatment option for many types of chronic pain, including back pain. The last 10 years has brought tremendous advances in the field of neuromodulation. Today, several treatment modalities exist for SCS requiring the physician to be able to critically evaluate and interpret the literature and determine which modality has the strongest evidence. When evaluating clinical trial data of patients with chronic back pain, emphasis must be placed on well designed, randomized controlled trials with long-term follow-up producing level I evidence. These data are obtained in a rigorous manner and are likely to have less bias when compared with lower level studies., Conclusion: The level I studies performed to date have provided evidence that treatment with SCS results in sustainable pain reduction and improvements in scores measuring quality of life and patient functioning in those patients with chronic intractable back pain., Level of Evidence: 5.

Study Design: Literature review., Objective: A review of the literature that presents a perspective on mechanisms of actions behind spinal cord stimulation (SCS) therapy for chronic pain., Summary of Background Data: SCS is an effective therapeutic alternative for the treatment of intractable chronic pain. Its application has been mostly based on the gate control theory of pain. Computational models have been fundamental on the understanding of clinical observations and the design of therapies that provide optimal neuromodulation. Research has provided insight into the involvement of specific neurotransmitters that support segmental and supraspinal mechanisms of action., Methods: A literature review was performed with emphasis on mechanisms of action for SCS including the effects of electrical fields on spinal cord structures based on computational models and preclinical and clinical explorations., Results: This review provides background on the development of SCS, which has been driven around a paresthesia-based paradigm as a result of the gate control theory. A review of computational models emphasizes their importance on our current understanding of the mechanism of action and clinical optimization of therapy. Electrophysiology and molecular biology have provided a closer, yet narrow, view of the effect of SCS on neurotransmitters and their receptors, which have led to the formulation of segmental and supraspinal mechanisms. Literature supporting the involvement of glial cells in chronic pain and their characteristic response to electrical fields should motivate further investigation of mechanisms involving neuroglia. Finally, a review of recent results paresthesia-free strategies should encourage research on mechanisms of action., Conclusion: The mechanisms of SCS have been extensively studied and several consistent phenomena have emerged. The activation of A-beta fibers to induce paresthesia also involve neurotransmitter release via segmental and supraspinal pathways. Despite advancements, much remains to be understood, particularly as new stimulation strategies are developed., Level of Evidence: N /A.

Study Design: A review of literature., Objective: The aim of this study was to define and explore the current evidence gaps in the use of spinal cord stimulation (SCS) for treating chronic spine conditions., Summary of Background Data: Although over the last 40 years SCS therapy has undergone significant technological advancements, evidence gaps still exist., Methods: A literature review was conducted to define current evidence gaps for the use of SCS. Areas of focus included 1) treatment of cervical spine conditions, 2) treatment of lumbar spine conditions, 3) technological advancement and device selection, 4) appropriate patient selection, 5) the ability to curb pharmacological treatment, and 6) methods to prolong efficacy over time. New SCS strategies using advanced waveforms are explored., Results: The efficacy, safety, and cost-effectiveness of traditional SCS for chronic pain conditions are well-established. Evidence gaps do exist. Recently, advancement in waveforms and programming parameters have allowed for paresthesia-reduced/free stimulation that in specific clinical areas may improve clinical outcomes. New waveforms such as 10-kHz high-frequency have resulted in an improvement in back coverage. To date, clinical efficacy data are more prevalent for the treatment of painful conditions originating from the lumbar spine in comparison to the cervical spine., Conclusion: Evidence gaps still exist that require appropriate study designs with long-term follow-up to better define and improve the use of this therapy for the treatment of chronic spine pain in both the cervical and lumbar regions., Level of Evidence: N/A.

Study Design: A randomized controlled trial with 2-week Kinesio taping intervention., Objective: The aim of the study was to investigate the effectiveness of Kinesio taping application on pain, functional disability, and trunk flexion range of motion (ROM) in patients with chronic nonspecific low back pain (chronic NSLBP)., Summary of Background Data: Kinesio taping is a therapeutic tool used for treatment of chronic NSLBP. However, there is little scientific evidence that describes its clinical efficacy., Methods: Forty-four patients with chronic NSLBP were randomized into experimental group (n = 21) and placebo group (n = 23). The experimental group was treated with Erector Spinae Taping, whereas the placebo group was treated with placebo taping. The primary endpoint was pain intensity on visual analog scale. Secondary endpoints were functional disability on Arabic version of Oswestry disability index (ODI) and trunk flexion ROM on Modified Schober's test. All measurements were recorded at baseline (W0), after 2-week intervention (W2), and at 4-week (W4) follow-up., Results: Both group were comparable at baseline (P > 0.05). The experimental group had a greater decrease in pain than the placebo group after W2 of intervention (mean between-group difference 2.05 cm, 95% confidence interval [CI] = 1.38-2.71 points). This was maintained to W4 follow-up (2.25 cm, 95% CI = 1.67-2.82 points). At W2, the experimental group had significantly greater improvement in disability, by 3.90 points (95% CI = 1.68-8.54 points). This effect was significant at W4 follow-up (5.6, 95% CI = 2.65-8.54 points). Similarly trunk flexion ROM was significantly better at W2 (-0.71 cm, 95% CI = -0.85 to -0.56) and W4 follow-up (-0.73 cm, 95% CI = -0.88 to -0.58)., Conclusion: Kinesio taping reduces pain and disability and improves trunk flexion ROM after 2 weeks of application. However, thesis effects were very small to be considered clinically relevant and meaningful when compared with placebo taping., Level of Evidence: 2.

Study Design: A three-arm controlled trial with adaptive allocation., Objectives: The aim of this study was to compare short-term effects of a side-lying, thrust spinal manipulation (SM) procedure and a nonthrust, flexion-distraction SM procedure in adults with subacute or chronic low back pain (LBP) over 2 weeks., Summary of Background Data: SM has been recommended in recently published clinical guidelines for LBP management. Previous studies suggest that thrust and nonthrust SM procedures, though distinctly different in joint loading characteristics, have similar effects on patients with LBP., Methods: Participants were eligible if they were 21 to 54 years old, had LBP for at least 4 weeks, scored 6 or above on the Roland-Morris disability questionnaire, and met the diagnostic classification of 1, 2, or 3 according to the Quebec Task Force Classification for Spinal Disorders. Participants were allocated in a 3:3:2 ratio to four sessions of thrust or nonthrust SM procedures directed at the lower lumbar and pelvic regions, or to a 2-week wait list control. The primary outcome was LBP-related disability using Roland-Morris Disability Questionnaire and the secondary outcomes were LBP intensity using visual analog scale, Fear-Avoidance Beliefs Questionnaire, and the 36-Item Short Form Health Survey. The study was conducted at the Palmer Center for Chiropractic Research with care provided by experienced doctors of chiropractic. Clinicians and patients were not blinded to treatment group., Results: Of 192 participants enrolled, the mean age was 40 years and 54% were male. Improvement in disability, LBP intensity, Fear-Avoidance Beliefs Questionnaire-work subscale, and 36-Item Short Form Health Survey-physical health summary measure for the two SM groups were significantly greater than the control group. No difference in any outcomes was observed between the two SM groups., Conclusion: Thrust and nonthrust SM procedures with distinctly different joint loading characteristics demonstrated similar effects in short-term LBP improvement and both were superior to a wait list control., Level of Evidence: 2.

Study Design: Retrospective Cohort., Objective: Our aim was to identify prognostic indicators for success after a back rehabilitation program (BR) in patients with nonspecific chronic low back pain (CLBP)., Summary of Background Data: Exercise therapy is recommended for patients with nonspecific CLBP. Consensus on the type of exercises is lacking, largely due to heterogeneity in the studied patient samples. The identification of subgroups through the identification of prognostic indicators is therefore needed. To our knowledge, no specific prognostic indicators for BR are described in the literature., Methods: We retrospectively analyzed the patient files of 49 nonspecific CLBP patients who followed a BR. Patients were selected based on predefined in- and exclusion criteria. All underwent 43 therapy sessions, two times per week. Primary outcome measure and dependent variable was the change in Oswestry Disability Questionnaire (ODI) score. Potential predictive variables were tested for association with the primary outcome and consequently entered in a logistic regression model., Results: In this study, the posthoc calculated power was 91%. Based on the change in ODI scores, 24 patients were considered as therapy success (eight points or 50% improvement on change in ODI score) and 25 as therapy failure. Univariate and multiple regression analysis revealed only one significant prognostic indicator: higher scores on the physical function subscale of the SF36 (PF-SF36) corresponded with high risk of therapy failure (odds ratio of 0.791 (95% CI =  .662-0.945); sensitivity of 0.79, and specificity of 0.68)., Conclusion: Potentially, the preset exercises of the BR in this study design were not appropriate for the identified subgroup. The results of this study should be replicated in a RCT design that conforms to the necessary methodological steps in the identification of prognostic indicators and clinical prediction rules (CPRs).

Study Design: A retrospective study with retrospective and prospective inclusion of 100 patients., Objective: To determine whether the sagittal balance (SB) influences the clinical outcome of patients with degenerative lumbar spinal stenosis, who underwent microsurgical decompression., Summary of Background Data: The SB has become a critical factor for clinical decision making in the surgical treatment of spinal degenerative diseases. However, a frequently recommended sagittal realignment of elderly, multimorbid patients is accompanied by a significant rate of complications. The influence of SB on the clinical outcome of patients with degenerative spinal stenosis, who undergo decompressive surgery is not well understood. The aim of this study was to explore whether the clinical outcome of these patients is related to the SB and whether patients with spinal stenosis and degenerative sagittal imbalance necessitate restoration of the SB in addition to microsurgical decompression., Methods: One hundred patients with lumbar spinal stenosis, who received microsurgical decompression, were retrospectively identified and classified according to the severity of sagittal imbalance: (1) normal balance group, (2) minor loss of balance group, and (3) major loss of balance group. Sagittal parameters were determined from preoperative lateral spinal radiographs. As outcome parameters, we analyzed pre- and postoperative visual analogue scales for leg and back pain, walking distance, Oswestry disability index, Roland and Morris disability questionnaire, Odom's criteria, and the SF-36 score., Results: All groups significantly benefited from surgery concerning leg pain, back pain, and disability in every day's life. There was no difference in patients with decompensated sagittal imbalance compared to patients with normal SB regarding life quality 6 to 24 months after microsurgical decompression., Conclusions: Patients with symptomatic degenerative spinal stenosis and excluded major instability significantly benefit from microsurgical decompression regardless of their sagittal spinal balance. Thus, restoration of the SB for patients with symptomatic degenerative spinal stenosis cannot be recommended in addition to microsurgical decompression., Level of Evidence: 3.

Study Design: Retrospective database analysis., Objective: A range of patient-reported outcomes were used to measure disability due to low back pain. There is not a single back pain disability measurement commonly used in all randomized controlled trials. We report here our assessment as to whether different disability measures are sufficiently comparable to allow data pooling across trials., Summary of Background Data: We used individual patient data from a repository of data from back pain trials of therapist-delivered interventions., Methods: We used data from 11 trials (n=6089 patients) that had at least 2 of the following 7 measurements: Roland-Morris Disability Questionnaire, Chronic Pain Grade disability score, Physical Component Summary of the 12- or 36-Item Short Form Health Survey, Patient Specific Functional Scale, Pain Disability Index, Oswestry Disability Index, and Hannover Functional Ability Questionnaire. Within each trial, the change score between baseline and short-term follow-up was computed for each outcome and this was used to calculate the correlation between the change scores and the Cohen's κ for the 3-level outcome of change score of less than, equal to, and more than zero. It was considered feasible to pool 2 measures if they were at least moderately correlated (correlation>0.5) and have at least moderately similar responsiveness (κ>0.4)., Results: Although all pairs of measures were found to be positively correlated, most correlations were less than 0.5, with only 1 pair of outcomes in 1 trial having a correlation of more than 0.6. All κ statistics were less than 0.4 so that in no cases were the criteria for acceptability of pooling measures satisfied., Conclusion: The lack of agreement between different outcome measures means that pooling of data on these different disability measurements in a meta-analysis is not recommended., Level of Evidence: 2.

Study Design: Retrospective cohort study., Objective: Determine how psychosocial factors, particularly depression, impact lumbar fusion outcomes in a workers' compensation (WC) setting., Summary of Background Data: WC patients are less likely to return to work (RTW) after fusion. Few studies evaluate risk factors within this clinically distinct population., Methods: A total of 2799 Ohio WC subjects were identified who underwent lumbar fusion between 1993 and 2013 using Current Procedural Terminology (CPT) procedural and International Classification of Diseases, Ninth Revision (ICD-9) diagnosis codes. A total of 123 subjects were diagnosed with depression before fusion. Subjects with a smoking history, prior lumbar surgery, permanent disability, and failed back syndrome were excluded. The primary outcome was whether subjects returned to work within 2 years of fusion and sustained this RTW for more than 6 months of the following year. To determine the impact depression had on RTW status, we performed a multivariate logistic regression analysis. We also compared time absent from work and other secondary outcomes using χ2 and t tests., Results: Subjects with preoperative depression had significantly higher rates of legal representation, degenerative lumbar disease, and higher medical costs, and used opioid analgesics for considerably longer before and after fusion (P<0.001).Depression group (10.6% [13/123]) and controls (33.0% [884/2676]) met our RTW criteria (P<0.001). Preoperative depression was a negative predictor of RTW status (P<0.001; odds ratio [OR]: 0.38). Additional predictors included working during same week as fusion (OR: 2.15), age more than 50 years (OR: 0.58), chronic preoperative opioid analgesia (OR: 0.58), and legal representation (OR: 0.64). After surgery, depression subjects were absent from work 184 more days compared with controls (P<0.001)., Conclusion: Overall, RTW rates after fusion were low, which was especially true for those with pre-existing depression. Depression was a strong negative predictor of postoperative RTW status. Psychological screening and treatment may be beneficial in these subjects. The poor outcomes in this study may highlight a more limited role for fusion among WC subjects with chronic low back pain where RTW is the treatment goal., Level of Evidence: 3.

Study Design: Markov cost-utility model., Objective: To evaluate the cost-utility of cognitive behavioral therapy (CBT) for the treatment of persistent nonspecific low back pain (LBP) from the perspective of US commercial payers., Summary of Background Data: CBT is widely deemed clinically effective for LBP treatment. The evidence is suggestive of cost-effectiveness., Methods: We constructed and validated a Markov intention-to-treat model to estimate the cost-utility of CBT, with 1-year and 10-year time horizons. We applied likelihood of improvement and utilities from a randomized controlled trial assessing CBT to treat LBP. The trial randomized subjects to treatment but subjects freely sought health care services. We derived the cost of equivalent rates and types of services from US commercial claims for LBP for a similar population. For the 10-year estimates, we derived recurrence rates from the literature. The base case included medical and pharmaceutical services and assumed gradual loss of skill in applying CBT techniques. Sensitivity analyses assessed the distribution of service utilization, utility values, and rate of LBP recurrence. We compared health plan designs. Results are based on 5000 iterations of each model and expressed as an incremental cost per quality-adjusted life-year., Results: The incremental cost-utility of CBT was $7197 per quality-adjusted life-year in the first year and $5855 per quality-adjusted life-year over 10 years. The results are robust across numerous sensitivity analyses. No change of parameter estimate resulted in a difference of more than 7% from the base case for either time horizon. Including chiropractic and/or acupuncture care did not substantively affect cost-effectiveness. The model with medical but no pharmaceutical costs was more cost-effective ($5238 for 1 yr and $3849 for 10 yr)., Conclusion: CBT is a cost-effective approach to manage chronic LBP among commercial health plans members. Cost-effectiveness is demonstrated for multiple plan designs., Level of Evidence: 2.

Study Design: This is a secondary analysis of a cross-sectional population-based survey., Objective: Shorten the modified 23-item Roland (mRoland) scale using item response theory (IRT) methods and describe where in the functional disability range each scale is the most precise., Summary of Background Data: The Roland-Morris Disability Questionnaire is recommended for a functional disability outcome measure in patients with low back pain (LBP). One commonly used version is the Roland. It is unknown where in the functional disability range the Roland measures., Methods: One candidate individual with LBP in randomly selected households was interviewed, identifying 694 adults with chronic LBP. To justify the use of a unidimensional 2-parameter logistic IRT model, we performed both exploratory and confirmatory factor analysis., Results: Exploratory factor analysis revealed one dominant eigenvalue. Confirmatory factor analysis results indicate that the 1-factor model fit well. IRT analysis revealed variability in the slopes, in the range from 1.07 to 3.10. The marginal reliability, an IRT-based analog to coefficient α, was 0.88. The mRoland produces reliable scores (i.e., with a standard error <0.3) from 1.4 standard deviations below the mean to roughly 0.2 above the mean., Conclusion: The mRoland measures one construct. The mRoland seems to be an excellent tool for measuring just-below-average levels of functional disability. The mRoland measures high levels of functional disability with relatively poor reliability and may be more appropriate for a less-disabled population with LBP. We demonstrate that the mRoland can be shortened to 11 items with minimal loss of information. We show that there are different ways to go about selecting the set of 11 items that yield short forms with different strengths., Level of Evidence: 3.

Unlabelled: Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients' lives. Such cLBP is often termed nonspecific and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. Therefore, NIH Pain Consortium charged a research task force to draft standards for research on cLBP. The resulting multidisciplinary panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimum data set to describe research participants (drawing heavily on the Patient Reported Outcomes Measurement Information System methodology); reporting "responder analyses" in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved the recommendations, which investigators should incorporate into NIH grant proposals. The research task force believes that these recommendations will advance the field, help resolve controversies, and facilitate future research addressing the genomic, neurological, and other mechanistic substrates of cLBP. We expect that the research task force recommendations will become a dynamic document and undergo continual improvement., Perspective: A task force was convened by the NIH Pain Consortium with the goal of developing research standards for cLBP. The results included recommendations for definitions, a minimum data set, reporting outcomes, and future research. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes.

Study Design: Cross-sectional study., Objective: To examine the sensitivity of 2 single-item questions compared with 2 longer questionnaires for screening depression and anxiety among patients with chronic low back pain (CLBP)., Summary of Background Data: Psychosocial factors are frequently identified as risk factors for developing CLBP and as predictors for treatment, and questionnaires are often used to screen for this. Shorter instruments may be easier to use in clinical practice settings., Methods: A total of 564 patients with 2 to 10 months of at least 50% sickness absence due to nonspecific low back pain were assessed for depression and anxiety with the Mini-International Neuropsychiatric Interview (MINI). Single-item questions for depression and anxiety from the Subjective Health Complaint Inventory and 2 longer questionnaires, the Hospital Anxiety and Depression Scale and Hopkins Symptom Checklist-25, were compared with MINI results, considered the "gold standard" in this study. Sensitivity and specificity of single-item and longer questionnaires and receiver operating characteristic curves were compared., Results: According to MINI, the prevalence of anxiety disorders was 12% whereas that of depressive disorders was 4%. The screening questions showed 95% sensitivity and 56% specificity for depressive disorders and 68% sensitivity and 85% specificity for anxiety disorders. The longer questionnaire, Hospital Anxiety and Depression Scale, showed 91% sensitivity and 85% specificity for depressive disorders and 58% sensitivity and 83% specificity for anxiety disorders. Hopkins Symptom Checklist-25 showed 86% sensitivity and 74% specificity for depressive disorders and 67% sensitivity and 87% specificity for anxiety disorders. For 3 of the anxiety disorders and 2 of the depressive disorders, a perfect sensitivity was found between the screening questions and MINI., Conclusions: A single-item screening question was sensitive for depression but less sensitive for anxiety. The screening questions further performed equal to 2 widely used questionnaires. Validation of these results in other populations and compared with other short-item screeners is needed.

Study Design: Cross sectional study., Objective: The goal of this study is to identify relationships between objectively measured and subjectively scored parameters and reported pain., Summary of Background Data: Studies have demonstrated the unreliability of magnetic resonance imaging (MRI)-based parameters to identify pathological pain generators of chronic low back pain, but they were based on visual inspection and subjective assessment of lumbar disc features. Advancements in computer image analysis provide objective measurements of lumbar disc features., Methods: Two radiologists evaluated 39 axial and sagittal T1- and T2-weighted MR images of patients with chronic axial low back pain (age, >65 yr) and graded 4 subjective lumbar disc parameters (T2 signal intensity, nucleus shape, Modic changes, and osteophyte formation) whose sum is the cumulative MRI score. Objective parameter, MRI index, was calculated as the product of the measured lumbar disc area and total disc MRI signal intensity. Discs were sorted from least to the most degenerated relative to each parameter. Pearson correlation coefficient and multiple linear regression analysis were performed between the reported pain score and each parameter., Results: The most and least degenerated discs in each patient, as assessed by MRI index, had the highest negative and positive correlation coefficient and regression weight contribution, respectively. All subjective parameters had low correlation coefficients and regression goodness of fit., Conclusion: Although limited by small sample size, the objective parameter, MRI index, can be a potential imaging biomarker used to identify possible pain generators. This study presents a potential new application of MR imaging in identifying pain generators of patients with chronic low back pain.

Study Design: Systematic review., Objective: To evaluate the validity of instruments that claim to detect submaximal capacity when maximal capacity is requested in patients with chronic nonspecific musculoskeletal pain., Summary of Background Data: Several instruments have been developed to measure capacity in patients with chronic pain. The detection of submaximal capacity can have major implications for patients. The validity of these instruments has never been systematically reviewed., Methods: A systematic literature search was performed including the following databases: Web of Knowledge (including PubMed and Cinahl), Scopus, and Cochrane. Two reviewers independently selected the articles based on the title and abstract according to the study selection criteria. Studies were included when they contained original data and when they objectified submaximal physical or functional capacity when maximal physical or functional capacity was requested. Two authors independently extracted data and rated the quality of the articles. The included studies were scored according to the subscales "Criterion Validity" and "Hypothesis Testing" of the COSMIN checklist. A Best Evidence Synthesis was performed., Results: Seven studies were included, 5 of which used a reference standard for submaximal capacity. Three studies were of good methodological quality and validly detected submaximal capacity with specificity rates between 75% and 100%., Conclusion: There is strong evidence that submaximal capacity can be detected in patients with chronic low back pain with a lumbar motion monitor or visual observations accompanying a functional capacity evaluation lifting test.

Study Design: Cross-cultural adaptation and psychometric testing., Objective: To conduct the cross-cultural adaptation of the Quebec Back Pain Disability Scale (QBPDS) and investigate its reliability and validity in patients with chronic low back pain (CLBP)., Summary of Background Data: The QBPDS is one of the most commonly used scales to evaluate functional incapacity resulting from low back pain. Although measuring disability is an important outcome in physiotherapy care, there is no previous research relating to the cultural adaptation and psychometric testing of the QBPDS in the Portuguese-speaking population., Methods: The questionnaire was first translated and back-translated in accordance with the published guidelines. The Portuguese version of the QBPDS was then pilot tested in a Portuguese sample of 40 patients with CLBP. Psychometric properties were evaluated in a new sample of 132 patients with CLBP. Exploratory factor analysis was performed to confirm its unidimensionality. Reliability was evaluated through internal consistency and reproducibility, using the Cronbach α and intraclass correlation coefficient, respectively. Construct validity was assessed with correlations between the QBPDS and the Roland-Morris Disability Questionnaire and between the QBPDS and the visual analogue pain scale for convergent validity and pain localization for discriminative validity, using the Spearman correlation analysis and the Mann-Whitney test., Results: Exploratory factor analysis revealed the existence of one major factor that explains 52.1% of the variance. One-week test-retest reliability was 0.7, and internal consistency was 0.95. The QBPDS correlated strongly with the Roland-Morris Disability Questionnaire (0.62; P < 0.001), moderately with pain (0.38; P < 0.001), and shows capability to discriminate between patients with localized and referred pain (U = 1218; P < 0.0005)., Conclusion: The reliability and construct validity of the Portuguese version of the QBPDS are acceptable to assess functional status of Portuguese-speaking patients with CLBP. .

Study Design: Cross-sectional evaluation of the psychometric properties of a translated questionnaire., Objective: To validate the Italian version of the Chronic Pain Acceptance Questionnaire (CPAQ) to allow its use with Italian-speaking patients with chronic low back pain (LBP)., Summary of Background Data: Growing attention is being given to cognitive-behavioral measures to improve interventions for LBP. The CPAQ has never been validated in Italian subjects with chronic LBP., Methods: The psychometric testing included confirmatory factor analysis, reliability by internal consistency (Cronbach α), test-retest reliability (intraclass correlation coefficient), sensitivity to change by calculating the smallest detectable change, and construct validity by comparing CPAQ with a pain numerical rating scale, the Roland-Morris Disability Questionnaire Scale, the Hospital Anxiety and Depression Scale, the Pain Catastrophizing Scale, and the Tampa Scale of Kinesiophobia (Pearson correlations). Hierarchical multiple regression analyses were computed to further investigate construct validity of the CPAQ subscales., Results: The questionnaire was administered to 142 subjects with chronic LBP. Factor analysis confirmed a 2-factor (viz., Activities Engagement and Pain Willingness) 20-item solution, achieving a good data-model fit. Internal consistency (α = 0.88) and test-retest reliability (intraclass correlation coefficient = 0.86) were good. The smallest detectable change was 22. Construct validity showed a moderate correlation between the CPAQ and numerical rating scale (r = -0.485), Roland-Morris Disability Questionnaire Scale (r = -0.594), and Tampa Scale of Kinesiophobia (r = -0.595), and a close correlation with Hospital Anxiety and Depression Scale (r = -0.610 for the Anxiety score and r = -0.659 for the Depression score) and Pain Catastrophizing Scale (r = -0.658). The standardized regression coefficients for Activity Engagement were significant in all of the equations, and those for Pain Willingness were significant in the anxiety, depression, and disability equations., Conclusion: The Italian CPAQ had a good factorial structure and psychometric properties that replicated the results of other versions. Its use is recommended for clinical and research purposes., Level of Evidence: 2.

Study Design: A cohort study with 1-year follow-up., Objective: To identify prognostic factors in patients with chronic nonspecific low back pain (LBP)., Summary of Background Data: The factors (e.g., sociodemographical, low back-related, radiological, and biological) associated with persistent pain and disability for patients with chronic nonspecific LBP are uncertain. Furthermore, sparse information exists about the relationship between biological factors like impaired fasting glucose tolerance and chronic nonspecific LBP., Methods: The participants consisted of 250 patients with nonspecific LBP of more than 6 months duration and degenerative lumbar osteoarthritis. The patients were originally recruited for a randomized controlled trial from the clinics of general practitioners, physiotherapists, and chiropractors. Potential predictors were evaluated at baseline. The outcome was absolute level of pain-related disability (Roland-Morris Disability Questionnaire [RMDQ]) at 1 year. The association between potential prognostic factors and the outcome was analyzed with multivariate linear backward regression., Results: At baseline and 1 year, the RMDQ scores were 9.5 and 5.1 points, respectively. Mean (SD) baseline values for body mass index (BMI), EuroQol (EQ)-index, EQ-visual analogue scale were 25.4 (4.3), 0.60 (0.3), and 61.2 (20.8), respectively. Higher pain-related disability levels (1-year RMDQ score) were associated with 6.1 mmol/L or more fasting glucose level at baseline (β, 3.7; 95% confidence interval [CI], 1.2-6.1; P = 0.00), baseline pain-related disability (β 0.2; 95% CI, 0.1-0.4; P = 0.00), BMI (β, 0.2; 95% CI, 0.1-0.3; P < 0.03), EQ-index (β, -4.5; 95% CI, 6.9 to 2.1; P = 0.00), and EQ-visual analogue scale (β, 0.3; 95% CI, -0.6 to -0.0; P = 0.03). However, a limited number of patients had 6.1 mmol/L or more of fasting glucose level at baseline (13/250 patients). The imaging findings, modic changes, and high intensity zones had no predictive ability., Conclusion: Increased pain-related disability at 1 year was seen in patients with impaired fasting glucose tolerance, greater pain-related disability, higher BMI, and lower quality of life at baseline.

Study Design: Systematic literature review., Objective: To assess the effect of total disc replacement for chronic low back pain due to lumbar degenerative disc disease compared with fusion or other treatment options., Summary of Background Data: There is an increasing use in disc replacement devices for degenerative disc disease, but their effectiveness compared with other interventions such as fusion of the motion segment or conservative treatment remains unclear., Methods: A comprehensive search in PubMedCentral, MEDLINE, EMBASE, BIOSIS, ClinicalTrials.gov, and FDA trials register was conducted. Randomized controlled trials comparing total disc replacement with any other intervention for degenerative disc disease were included. Risk of bias was assessed using the criteria of the Cochrane Back Review Group. Quality of evidence was graded according to the GRADE approach. Two review authors independently selected studies, assessed risk of bias, and extracted data. Results and upper bounds of confidence intervals were compared with predefined clinically relevant differences., Results: We included 7 randomized controlled trials with a follow-up of 24 months. There is risk of bias in the included studies due to sponsoring and absence of any kind of blinding. One study compared disc replacement with rehabilitation and found a significant advantage in favor of surgery, which, however, did not reach the predefined threshold. Six studies compared disc replacement with fusion and found that the mean improvement in visual analogue scale score of back pain was 5.2 mm higher (2 studies; 95% confidence interval 0.2-10.3) with a low quality of evidence. The improvement of Oswestry disability index score at 24 months in the disc replacement group was 4.3 points more than in the fusion group (5 studies; 95% confidence interval 1.85-6.68) with a low quality of evidence. Both upper bounds of the confidence intervals were below the predefined clinically relevant difference., Conclusion: Although statistically significant, the differences in clinical improvement were not beyond generally accepted boundaries for clinical relevance. Prevention of adjacent level disease and/or facet joint degeneration was not properly assessed. Therefore, because we think that harm and complications may occur after some years, the spine surgery community should be prudent to adopt this technology on a large scale, despite the fact that total disc replacement seems to be effective in treating low back pain in selected patients, and in the short term is at least equivalent to fusion surgery.

Study Design: Randomized clinical trial with 2-year follow-up., Objective: To assess the development of adjacent level degeneration (ALD) and index level facet arthropathy (FA) in patients treated with disc prosthesis compared with patients treated with rehabilitation., Summary of Background Data: There is controversy about the natural history of disc degeneration and the development of ALD and FA in patients who undergo disc prosthesis surgery., Methods: The study included 116 patients with a history of low back pain for at least 1 year, Oswestry Disability Index 30 points or more, and degenerative changes in 1 or 2 lower lumbar spine levels. Magnetic resonance imaging was performed before treatment and at the 2-year follow-up. ALD and index level FA were determined on the basis of the majority assessment of 3, independent, experienced radiologists. ALD was assessed by evaluating Modic changes, posterior high intensity zone in the disc, nucleus pulposus signal, disc height, disc contour, and FA. Data were analyzed with Fischer exact test and t test., Results: ALD developed with similar frequencies in patients who were (n = 59) and were not (n = 57) treated with surgery. In patients treated with surgery, index level FA appeared or increased in 20 patients (34%) and decreased in 1 patient. In patients treated with rehabilitation, 2 (4%) had new or increased FA at the index/degenerated disc level and 1 had decreased FA (P < 0.001). The development of ALD and FA was not related to clinical outcome., Conclusion: In this first study that compared the courses of degeneration after treatment with disc prosthesis surgery or rehabilitation, ALD was observed at similar frequencies at the 2-year follow-up. However, the surgery group had increased FA at the implant level.

Study Design: A randomized controlled trial., Objective: To compare changes in self-rated disability, pain, and anticipatory postural adjustments between specific trunk exercise and general exercise in patients with chronic low back pain., Summary of Background Data: Chronic low back pain is associated with altered motor control of the trunk muscles. The best exercise to address altered motor control is unclear., Methods: Sixty-four patients with chronic low back pain were randomly assigned to a specific trunk exercise group (SEG) that included skilled cognitive activation of the trunk muscles in addition to a number of other best practice exercises, whereas the general exercise group performed only seated cycling exercise. The training program lasted for 8 weeks. Self-rated disability and pain scores were collected before and after the training period. Electromyographic activity of various trunk muscles was recorded during performance of a rapid shoulder flexion task before and after training. Muscle onsets were calculated, and the latency time (in ms) between the onset of each trunk muscle and the anterior deltoid formed the basis of the motor control analysis., Results: After training, disability was significantly lower in the SEG (d = 0.62, P = 0.018). Pain was reduced in both groups after training (P < 0.05), but was lower for the SEG (P < 0.05). Despite the general exercise group performing no specific trunk exercise, similar changes in trunk muscle onsets were observed in both groups after training., Conclusion: SEG elicited significant reductions in self-rated disability and pain, whereas similar between-group changes in trunk muscle onsets were observed. The motor control adaptation seems to reflect a strategy of improved coordination between the trunk muscles with the unilateral shoulder movement. Trunk muscle onsets during rapid limb movement do not seem to be a valid mechanism of action for specific trunk exercise rehabilitation programs.

Study Design: A randomized controlled trial., Objective: To assess the effectiveness of Delitto's classification-based treatment approach compared with usual physical therapy care in patients with subacute or chronic low back pain., Summary of Background Data: No trial has evaluated this approach in patients with subacute and chronic low back pain., Methods: Before randomization, all patients were classified by research physical therapists according to a modified version of Delitto's classification-based system. Randomization was computer-generated, with centralized allocation concealment. The statistician and the physical therapists were unblinded. Patients and assistants who collected follow-up questionnaires were blinded. Follow-up assessments were completed at 8, 26, and 52 weeks. The primary analysis was performed according to the intention-to-treat principle, using multilevel analysis. The main outcomes were global perceived effect, disability (Oswestry Disability Index, 0-100), and pain intensity (Numerical Rating Scale, 0-10). Secondary outcomes were quality of life, fear-avoidance beliefs, and psychosocial status. RESULTS.: A total of 156 patients were included (classification-based group, n = 74; usual physical therapy group, n = 82). There were no statistically significant differences between the treatment groups for any of the outcomes at any of the follow-up time points. After 8 weeks, patients in the classification-based group had greater global perceived effect scores; adjusted odds ratio of 1.01 (95% confidence interval [CI], 0.31 to 3.28), and higher adjusted Oswestry Disability Index and Numerical Rating Scale scores; mean adjusted differences of 0.48 points (95% CI, -4.59 to 3.63) and 0.49 points (95% CI, -1.34 to 0.37) respectively, but all differences were statistically nonsignificant., Conclusion: The classification-based system used in this study was not effective for improving physical therapy care outcomes in a population of patients with subacute and chronic low back pain.

Study Design: A randomized controlled trial., Objective: To investigate feed-forward activation or timing of abdominal muscle activation in response to rapid shoulder flexion after 8 weeks with core stability exercises, sling exercises, or general exercises in chronic nonspecific low back pain (LBP) patients., Summary of Background Data: Delayed onset in abdominal muscles has been associated with LBP. Low load exercises to volitionally activate the transversus abdominis were introduced to restore trunk muscle activation deficits. More forceful co-contraction exercises have been advocated by others. This study explored whether abdominal muscle onset changed after low-load core stability exercises, high-load sling exercises, or general exercises., Methods: Subjects (N = 109) with chronic nonspecific LBP of at least 3 months' duration were randomly assigned to 8 weekly treatments with low-load core stability exercises, high-load stabilizing exercises in slings, or general exercises in groups. Primary outcome was onset recorded bilaterally by m-mode ultrasound imaging in the deep abdominal muscles in response to rapid shoulder flexion., Results: No or small changes were found in onset after treatment. Baseline adjusted between group differences showed a 15 ms (95% confidence interval [CI], 1-28; P = 0.03) and a 19 ms (95% CI, 5-33; P < 0.01) improvement with sling relative to core stability and general exercises, respectively, but on 1 side only. There was no association between changes in pain and onset over the intervention period (R ≤ 0.02)., Conclusion: Abdominal muscle onset was largely unaffected by 8 weeks of exercises in chronic LBP patients. There was no association between change in onset and LBP. Large individual variations in activation pattern of the deep abdominal muscles may justify exploration of differential effects in subgroups of LBP.

Study Design: Prospective cohort study., Objective: We explored long-term associations between physical load exposure and chronic low back pain (LBP) using data from an ongoing population-based cohort study., Summary of Background Data: Physical load in work or daily life is often studied in relation to LBP. Most studies are cross-sectional or have a limited follow-up., Methods: Between 1993 and 2007, 4738 men and women aged 25 to 64 years were measured maximal 3 times with 5-year intervals. Physical load in daily activities (9 items, e.g., awkward postures, mechanical vibration) was assessed by questionnaire at 2 measurements and chronic LBP 3 times. Physical load exposure at both measurements was described. Multivariable logistic regression analyses were adjusted for sex, age, education, work status, body mass index, physical activity, and smoking., Results: Despite stable prevalence rates of physical load exposure, about 50% of the participants exposed changed their exposure during a 5-year period. 7.2% of the participants reported awkward postures at 2 measurements, 8.4% at the first measurement only, and 6.8% at the second measurement only. Among all physical load variables, associations with chronic LBP were found only for awkward postures. An increased risk for incident chronic LBP was found in participants exposed twice to awkward postures. In contrast, only single exposure to awkward postures was associated with persistence of chronic LBP., Conclusion: Awkward postures were associated with chronic LBP in the general population. Exposure to awkward postures at 2 measurements with 5 years in between did increase the risk for incident chronic LBP, but not for persistence of chronic LBP.

Study Design: Prospective cohort study., Objective: The objective of this study was to test the responsiveness and minimal clinically important change (MCIC) of the Pain Disability Index (PDI) in patients with chronic back pain (CBP)., Summary of Background Data: Treatment of patients with CBP is primarily focused on reduction of disability. For disability measurement, the PDI is a widely used questionnaire. There are, however, no data available on responsiveness and MCIC., Methods: Two hundred forty-two patients with CBP were included in this study. Patients filled in the PDI at baseline and at discharge. The PDI consists of 2 subscales: 1 measuring voluntary activities and 1 measuring obligatory activities. PDI was anchored at 2 self-reported global perceived effect (GPE) scales for complaints and self-care, respectively. Responsiveness was considered sufficient when Area Under the Receiver Operating Characteristics (ROC) Curve (AUC) was higher than 0.70. To test interpretability, change scores and MCIC were calculated. MCIC was tested by determination of optimal cut-off point of the ROC curve and determination of specificity and sensitivity of the optimal cut-off point., Results: AUCs were 0.76 and 0.77 depending on the external criterion. The subscale obligatory activities did not meet the criteria for responsiveness (AUC: 0.63-0.69). MCIC of the PDI was 9.5 points for GPE "complaints" and 8.5 for GPE "self-care.", Conclusion: The total score of the PDI as well as the subscale of voluntary activities is responsive. Partly because of floor effects, the subscale obligatory activities are not sufficiently responsive in patients with CBP. However, the responsiveness of this subscale in other patient groups should be further tested. In patients with CBP, change can be considered clinically important when PDI score has decreased 8.5 to 9.5 points.

Study Design: Prospective cohort study., Objective: To assess the prognosis of patients presenting with acute low back pain (LBP) in a primary care setting in the United States., Summary of Background Data: Practice guidelines for acute LBP based on return-to-work outcomes underestimate the development of chronic pain in the primary care setting. Because of differences in inclusion criteria, chronic pain definitions, and national health systems, prognostic cohort studies have reported a wide range of results limiting interpretation and generalization. Current data from carefully designed prognostic studies of acute LBP are lacking for the US primary care system., Methods: Members of a large health service organization were enrolled after seeking medical care for acute LBP, with or without sciatica, of up to 30 days duration, with no episode in the past 12 months and no history of spine surgery. We conducted phone interviews at baseline, 6 months, and 2 years. Based on receiver operating characteristic analyses, a combination of global perceived recovery with pain intensity was used as primary outcome for chronic pain. Recurrence and multiple secondary outcomes were assessed to allow for comparison with other studies., Results: Six hundred five patients had an average pain intensity of 5.6 (numeric rating scale = 0-10) and disability of 15.8 (Roland-Morris scale = 0-24). Eight percent had declared sick leave between pain onset and baseline interview. Thirteen percent of 521 patients (86% follow-up) experienced chronic pain at 6 months and 19% of 443 patients at 2 years. At 6 months, 54% had experienced at least 1 LBP recurrence, and 47% in the subsequent 18 months., Conclusion: The prognosis of strictly defined acute LBP, with or without sciatica, is less favorable than commonly stated in practice guidelines based on failure to return to work. Broad initiatives to develop new means for the primary and secondary prevention of recurrent and chronic LBP are urgently needed.

Study Design: A cross-sectional study., Objective: To analyze the relationship between resilience, acceptance, coping, and adjustment to spinal chronic pain., Summary of Background Data: Several studies have concluded that resilience is relevant in predicting pain and physical functioning among patients with chronic pain. Although resilience may have a role in preventing or living with chronic pain, there is little research on the effects of resilience on adjustment among patients with chronic pain., Methods: Multivariate multiple regression by structural equation modeling was performed to simultaneously determine the influence of all the predictor variables on all the dependent variables. The sample was composed of 299 patients (138 men and 161 women) suffering from chronic spinal pain. : Higher levels of resilience were associated with higher levels of pain acceptance and active coping strategies. Active coping and acceptance were associated with higher levels of adjustment to pain., Conclusion: Positive personality characteristics could play a crucial role in patient adjustment, and thus clinicians should take into account the positive path to capacity to better understand the chronic pain experience.

Study Design: Intensity of pain and level of disability (Oswestry Disability Index [ODI]) were compared with the relative size of Modic type 1 (M1) and Modic type 2 (M2) lesions. Clinical symptoms of patients having mixed M1-M2 lesion (n = 49) were compared with patients having a "pure" M1 lesion (n = 13)., Objective: To determine the relation of the sizes of M1 and M2 lesions and the type of Modic lesion (mixed M1-M2 or pure M1 lesion) with intensity of low back pain and level of perceived disability., Summary of Background Data: Endplate signal abnormalities, particularly M1 changes indicating edema and inflammation, have been suggested to play an important role in the etiopathogenesis of a subgroup of patients with nonspecific chronic low back pain (CLBP). However, their association with clinical symptoms has not been studied in detail previously., Methods: Sixty-two CLBP patients with a large M1 lesion were selected from CLBP patients who were sent for the first time for standard lumbar spine magnetic resonance imaging at a university hospital. To exclude other causes of CLBP, as far as possible, strict exclusion criteria were used: any specific back disease, even a slight nerve root compression, a recent or major spine operation, or age older than 65 years. The relative sizes of M1 and M2 lesions were visually estimated from sagittal images for comparison with clinical symptoms., Results: The majority of patients (91.9%; 57 of 62) had an M1 lesion at a single level, 92% of the lesions being at L4-L5 or L5-S1 level. Forty-nine patients (79.0%) had a mixed M1-M2 lesion, and 13 (21.0%) had a pure M1 lesion. The mean of the pain intensity score was 6.2, and, correspondingly, the Oswestry Disability Index was 30.4. The mean relative sagittal area of the largest M1 lesion was 24.6% (SD = 16.2), and that of the M2 lesion was 10.9% (SD = 11.6). Neither the pain intensity nor the ODI scores were found to correlate with the largest relative size of the M1 lesion. The patients with "pure" M1 lesion had statistically significantly more clinical symptoms than patients having a mixed M1-M2 lesion., Conclusion: We conclude that the size of M1 lesion does not directly correlate with the clinical symptoms but that the type of Modic lesion is more important. This study supports the previous observations that when the inflammatory process turns to the mixed M1-M2 lesions, clinical symptoms decrease.

Study Design: A prospective cohort study., Objective: To establish outcome measures for recovery and chronic pain for studies with patients who present with recent-onset acute low back pain (LBP) in primary care., Summary of Background Data: Among back pain researchers, no consensus exists about outcome definitions or how to identify primary-care patients as not-recovered from an episode of LBP. Cut points for outcome scales have mostly been arbitrarily chosen. Theoretical models for establishing minimal important change values in studies of patients with LBP have been proposed and need to be applied to real data., Methods: A sample of 521 patients who presented with acute LBP (<4 weeks) in primary care clinics were observed for 6 months and scores for pain and disability were compared with ratings on a Global Perceived Effect Scale. Using multiple potential "gold standards" as anchors (reference standards), the receiver operating characteristic method was used to determine optimal cut points for different ways of defining nonrecovery from acute LBP., Results: Minimal important change values and upper limits for pain and disability scores as well as minimal important percentage changes are presented for five different definitions of recovery. A previously suggested 30% change from baseline scores does not accurately discriminate between recovered patients and nonrecovered patients in patients presenting with acute LBP in primary care., Conclusion: Outcome definitions that combine ratings from perceived recovery scales with pain and disability measures provide the highest accuracy in discriminating recovered patients from nonrecovered patients.