Association of meeting 24-hour movement guidelines with low back pain among adults

Background

According to recently published 24-hour movement guidelines, adults should spend: ≥150 minutes/week in moderate-to-vigorous physical activity (MVPA); <8 hours/day in sedentary behaviour (SB); and 7-9 hours/day sleeping.

Objective

We explored the association between meeting these recommendations and low back pain (LBP)-the most common musculoskeletal disorder.

Methods

We collected self-reported data from 2333 adults about: MVPA, SB and sleep duration; frequency and intensity of LBP; and sociodemographic and lifestyle characteristics.

Results

Meeting a combination of SB and sleep recommendations was associated with lower odds of LBP in the past week and past month (adjusted odds ratio [OR]: 0.64 and 0.52, respectively; p < 0.05 for both). Among LBP sufferers, meeting any combination of recommendations that includes sleep was associated with lower odds of frequent (OR range: 0.49-0.61; p < 0.05 for all) and intense (OR range: 0.39-0.66; p < 0.05 for all) LBP in the past week, while meeting a combination of SB and sleep recommendations or all three recommendations was associated with lower odds of intense LBP in the past month and past year (OR range: 0.50-0.68; p < 0.05 for all). The likelihood of experiencing higher frequency and intensity of LBP decreased with the number of recommendations met (p for linear trend < 0.05).

Conclusion

Meeting the SB and sleep recommendations in combination is associated with a lower likelihood of LBP, while adhering to the overall 24-hour movement guidelines or any combination of recommendations that includes sleep is associated with lower frequency and intensity of LBP among LBP sufferers.

Consistent differences in lumbar spine alignment between low back pain subgroups and genders during clinical and functional activity sitting tests

BACKGROUND

Subgroups of people with low back pain display differences in their lumbar alignment during tests from a clinical examination. However, it is unknown if subgroups display the same patterns during a functional activity test and if gender influences subgroup-related differences.

OBJECTIVES

Test if differences in lumbar alignment between two LBP subgroups are 1) present during a functional activity test of preferred sitting and 2) independent of gender.

DESIGN

Cross-sectional.

METHOD

154 participants with chronic low back pain were classified based on the Movement System Impairment Classification System by a physical therapist. Participants performed a functional activity test of preferred sitting and clinical tests of maximum flexed and extended sitting. 3D marker co-ordinate data were collected. Sagittal plane lumbar alignment, indexed by lumbar curvature angle, was calculated. A three-way mixed effect analysis of variance was used to examine effects of test, subgroup, gender, subgroup × test, gender × test and subgroup × gender.

RESULTS/FINDINGS

The lumbar rotation with extension subgroup [LCA = -8.0° (-9.5,-6.5)] displayed a more extended lumbar alignment than lumbar rotation [LCA = -5.9° (-7.4,-4.4)]. Women [LCA = -10.7° (-12.3,-9.2)] displayed a more extended lumbar alignment than men [LCA = -3.2° (-4.7,-1.7)]. There was a significant gender × test interaction (p = 0.01). The subgroup × test (p = 0.99) and subgroup × gender (p = 0.76) interactions were not significant.

CONCLUSIONS

LBP subgroup differences in lumbar alignment are present during preferred sitting. Gender-related differences in lumbar alignment are not driving subgroup differences. These findings highlight the need to use patient-specific clinical characteristics to guide treatment of a functional activity of preferred sitting limited due to low back pain.

Classification of patients with low back-related leg pain: a systematic review

BACKGROUND

The identification of clinically relevant subgroups of low back pain (LBP) is considered the number one LBP research priority in primary care. One subgroup of LBP patients are those with back related leg pain. Leg pain frequently accompanies LBP and is associated with increased levels of disability and higher health costs than simple low back pain. Distinguishing between different types of low back-related leg pain (LBLP) is important for clinical management and research applications, but there is currently no clear agreement on how to define and identify LBLP due to nerve root involvement. The aim of this systematic review was to identify, describe and appraise papers that classify or subgroup populations with LBLP, and summarise how leg pain due to nerve root involvement is described and diagnosed in the various systems.

METHODS

The search strategy involved nine electronic databases including Medline and Embase, reference lists of eligible studies and relevant reviews. Selected papers were appraised independently by two reviewers using a standardised scoring tool.

RESULTS

Of 13,358 initial potential eligible citations, 50 relevant papers were identified that reported on 22 classification systems. Papers were grouped according to purpose and criteria of the classification systems. Five themes emerged: (i) clinical features (ii) pathoanatomy (iii) treatment-based approach (iv) screening tools and prediction rules and (v) pain mechanisms. Three of the twenty two systems focused specifically on LBLP populations. Systems that scored highest following quality appraisal were ones where authors generally included statistical methods to develop their classifications, and supporting work had been published on the systems' validity, reliability and generalisability. There was lack of consistency in how LBLP due to nerve root involvement was described and diagnosed within the systems.

CONCLUSION

Numerous classification systems exist that include patients with leg pain, a minority of them focus specifically on distinguishing between different presentations of leg pain. Further work is needed to identify clinically meaningful subgroups of LBLP patients, ideally based on large primary care cohort populations and using recommended methods for classification system development.

A process of subgroup identification in non-specific low back pain using a standard clinical examination and cluster analysis

BACKGROUND AND PURPOSE

Non-specific low back pain (NSLBP) accounts for over 85% of all low back pain. Homogenous subgroups may exist within this diagnosis. This study derived a clinical examination and evaluated the examination's ability to identify homogenous subgroups in NSLBP.

METHODS

Patients with NSLBP were examined using a standardized clinical examination. Each patient was examined by two physiotherapists. Data were analysed for item reliability and the presence of distinct subgroups using cluster analysis. Cross-validation of the clusters identified was conducted.

RESULTS

Three hundred and one patients were examined. The inter-tester reliability of the majority of items was moderate to substantial (52% of items with kappa > 0.40). A K-means cluster analysis of the two data sets revealed agreement on the presence of two subgroups. One group (n = 47, 16%) had higher fear avoidance beliefs, anxiety and disability. They were more likely to be provoked by pain provocative tests. They were also more likely to be judged as having central sensitization and a dominant psychosocial component to their presentation.

CONCLUSION

The identification of a group of hypervigilant NSLBP patients should allow the interventions to be targeted towards this group. A valid, standardized clinical examination does contribute to the diagnostic management of NSLBP.

The validity of O'Sullivan's classification system (CS) for a sub-group of NS-CLBP with motor control impairment (MCI): overview of a series of studies and review of the literature

Chronic Low Back Pain (LBP) remains a common, recalcitrant and costly problem for the individual sufferer and for society. Effective treatments that reduce the social and economic burden have yet to be established for the majority of chronic LBP cases. Lack of evidence for specific interventions has been blamed on the heterogeneity of the chronic LBP population as well as a lack of a patient centred bio-psycho-social approach. This issue of heterogeneity has resulted in classification being considered the highest research priority in the area of chronic LBP. The potential for a 'wash-out effect' caused by the heterogeneity of the chronic LBP populations sampled for randomised controlled clinical trials (RCTs), has driven the need for classifying patients with nonspecific chronic LBP. A summary of a series of studies is outlined in this review paper. They represent a comprehensive investigation into the validity of O'Sullivan's proposed mechanism-based classification system (CS) for a sub-group of localized mechanically provoked nonspecific chronic LBP with motor control impairment (MCI). Further, the findings of these studies are discussed in relation to the relevant literature and the clinical implications arising are presented. Finally, the limitations of this research are outlined and recommendations for future research are made.

Research methods for subgrouping low back pain

Background

There is considerable clinician and researcher interest in whether the outcomes for patients with low back pain, and the efficiency of the health systems that treat them, can be improved by 'subgrouping research'. Subgrouping research seeks to identify subgroups of people who have clinically important distinctions in their treatment needs or prognoses. Due to a proliferation of research methods and variability in how subgrouping results are interpreted, it is timely to open discussion regarding a conceptual framework for the research designs and statistical methods available for subgrouping studies (a method framework). The aims of this debate article are: (1) to present a method framework to inform the design and evaluation of subgrouping research in low back pain, (2) to describe method options when investigating prognostic effects or subgroup treatment effects, and (3) to discuss the strengths and limitations of research methods suitable for the hypothesis-setting phase of subgroup studies.

Discussion

The proposed method framework proposes six phases for studies of subgroups: studies of assessment methods, hypothesis-setting studies, hypothesis-testing studies, narrow validation studies, broad validation studies, and impact analysis studies. This framework extends and relabels a classification system previously proposed by McGinn et al (2000) as suitable for studies of clinical prediction rules. This extended classification, and its descriptive terms, explicitly anchor research findings to the type of evidence each provides. The inclusive nature of the framework invites appropriate consideration of the results of diverse research designs. Method pathways are described for studies designed to test and quantify prognostic effects or subgroup treatment effects, and examples are discussed. The proposed method framework is presented as a roadmap for conversation amongst researchers and clinicians who plan, stage and perform subgrouping research.

Summary

This article proposes a research method framework for studies of subgroups in low back pain. Research designs and statistical methods appropriate for sequential phases in this research are discussed, with an emphasis on those suitable for hypothesis-setting studies of subgroups of people seeking care.

Chronic non-specific low back pain - sub-groups or a single mechanism?

BACKGROUND

Low back pain is a substantial health problem and has subsequently attracted a considerable amount of research. Clinical trials evaluating the efficacy of a variety of interventions for chronic non-specific low back pain indicate limited effectiveness for most commonly applied interventions and approaches.

DISCUSSION

Many clinicians challenge the results of clinical trials as they feel that this lack of effectiveness is at odds with their clinical experience of managing patients with back pain. A common explanation for this discrepancy is the perceived heterogeneity of patients with chronic non-specific low back pain. It is felt that the effects of treatment may be diluted by the application of a single intervention to a complex, heterogeneous group with diverse treatment needs. This argument presupposes that current treatment is effective when applied to the correct patient. An alternative perspective is that the clinical trials are correct and current treatments have limited efficacy. Preoccupation with sub-grouping may stifle engagement with this view and it is important that the sub-grouping paradigm is closely examined. This paper argues that there are numerous problems with the sub-grouping approach and that it may not be an important reason for the disappointing results of clinical trials. We propose instead that current treatment may be ineffective because it has been misdirected. Recent evidence that demonstrates changes within the brain in chronic low back pain sufferers raises the possibility that persistent back pain may be a problem of cortical reorganisation and degeneration. This perspective offers interesting insights into the chronic low back pain experience and suggests alternative models of intervention.

SUMMARY

The disappointing results of clinical research are commonly explained by the failure of researchers to adequately attend to sub-grouping of the chronic non-specific low back pain population. Alternatively, current approaches may be ineffective and clinicians and researchers may need to radically rethink the nature of the problem and how it should best be managed.

Manual physical assessment of spinal segmental motion: intent and validity

Validity of a clinical test can be defined as the extent to which the test actually assesses what it is intended to assess. In order to investigate the validity of manual physical assessment of the spine, it is therefore essential to establish what physical therapists intend to assess when they are applying these tests. The aims of this study were to (1) establish what manual physical therapists are intending to assess while applying passive intervertebral motion tests; and (2) examine the face validity and content validity for manual physical assessment of the spine. We surveyed 1502 members of the national manual physical therapist organisations of New Zealand and the United States of America using a web-based survey instrument. Sixty-six percent of 466 respondents believed passive accessory intervertebral motion (PAIVM) tests were valid for assessing quantity of segmental motion, and 76% believed passive physiologic intervertebral motion (PPIVM) tests were valid for assessing quantity of segmental motion. Ninety-eight percent of manual physical therapists base treatment decisions at least in part on the results of segmental motion tests. Quality of resistance to passive segmental motion was considered of greater importance than quantity of kinematic motion during PAIVM tests, while the quality of complex kinematic motion was considered of greater importance than quantity of displacement kinematics during PPIVM tests. Manual physical therapists accept the face validity of manual physical assessment of spinal segmental motion to a great extent, however a minority voice scepticism. Content validity is dominated by concepts of segmental kinematics and the force-displacement relationship. Intent of assessment does, however, vary widely between therapists. These data will inform the design of concurrent validity studies. Further work is recommended to increase consistency of intent, methodology and terminology in manual physical assessment of the spine.

Indicators of lumbar zygapophyseal joint pain: survey of an expert panel with the Delphi technique

BACKGROUND AND PURPOSE

The lumbar zygapophyseal joints (LZJs) are thought to be a source of low back pain (LBP); however, no valid or reliable indicators exist. The purpose of this study was to obtain a consensus from an expert panel on the indicators of LZJ pain.

SUBJECTS

A multidisciplinary panel of 20 experts in the field of LBP participated in this study.

METHODS

A 3-round Delphi survey designed to obtain a consensus on the indicators of LZJ pain was completed by use of accepted protocols. Subjects also were asked to justify their selection of each indicator.

RESULTS

Following the 3 rounds, consensus was achieved, and 12 indicators were identified. Those that reached the highest levels of consensus were a positive response to facet joint injection, localized unilateral LBP, positive medial branch block, pain upon unilateral palpation of the LZJ or transverse process, lack of radicular features, pain eased by flexion, and pain, if referred, located above the knee. Justifications for the experts' selection of the indicators, predominantly based on pathoanatomical mechanisms, also were described.

DISCUSSION AND CONCLUSION

This Delphi survey identified 12 indicators of LZJ pain, each with an associated pathoanatomical mechanism justifying selection. This survey provides preliminary validation for these indicators, which will be of value in further research into the classification and treatment of LZJ pain.

Subclassification of low back pain: a cross-country comparison

Various health professionals have attempted to classify low back pain (LBP) subgroups and have developed several LBP classification systems. Knowing that culture has an effect on LBP symptomatology, assessment findings and clinical decision making, the aim of this review is to perform a cross-country comparative review amongst the published classification systems, addressing each country's similarities and differences as well as exploring whether cultural factors have been incorporated into the subclassification process. A systematic search of databases limited to human adults was undertaken by Medline, Cinahl, AMED and PEDro databases between January 1980 and October 2005. Classification systems from nine countries were identified. Most studies were classified according to pathoanatomic and/or clinical features, whereas fewer studies utilized a psychosocial and even less, a biopsychosocial approach. Most studies were limited in use to the country of the system's developer. Very few studies addressed cultural issues, highlighting the lack of information on the impact of specific cultural factors on LBP classification procedures. However, there seem to be certain 'cultural trends' in classification systems within each country, which are discussed. Despite the plethora of classification studies, there is still no system which is internationally established, effective, reliable and valid. Future research should aim to develop a LBP classification system within a well identified cultural setting, addressing the multi-dimensional features of the LBP presentation.

McKenzie classification of mechanical spinal pain: profile of syndromes and directions of preference

The purpose of this study was to develop a profile of the use of McKenzie classifications of diagnosis and treatment, by physiotherapists credentialed in the McKenzie method in New Zealand. This system has been in common use for more than 20 years and the inter-rater reliability of the assessment has been previously established for therapists at this level of training. Prior studies identifying the classification of patients according to syndrome and directional preference have been mainly for the lumbar spine. The 34 participants for this study each assessed and classified 10 consecutive spinal patients during a 10-week period. Of the 340 patients assessed, 19 were excluded. Of those with pain arising from the lumbar spine; 140/187 were classified as reducible derangement syndrome, 11/187 were classified as irreducible derangement, 11/187 as dysfunction syndrome, 1/187 as posture syndrome and 24/187 as 'other'. For treatment in the reducible derangement syndrome; 98/140 were given extension, 8/140 were given flexion and 34/140 were given lateral movements of either side gliding or rotation. Classifications and treatment for the cervical and thoracic spine groups followed similar patterns. These findings add to the external validity of the McKenzie method, and support mechanical evaluation of spinal patients according to directional preference.

Dynamic control of the lumbopelvic complex; lack of reliability of established test procedures

Impairment of the dynamic control of the lumbopelvic complex in LBP has gained increased focus both clinically and experimentally. The objectives of this study were to determine the reliability of inclinometry as a measure of dynamic lumbopelvic control. Lumbopelvic reposition accuracy during pelvic tilts was measured in 39 healthy subjects using an inclinometer attached to the skin at S2 level. The reposition accuracy was measured in sitting, standing and supported standing. Tests were performed three times with a 20 min recess between tests. Only data from the last two test sequences were used in order to account for learning effects. Intraclass correlation coefficients were low for the sitting (0.54) and supported standing positions (0.36). In the standing position, a significant difference between test and retest was observed (P = 0.003) and further reliability analysis was therefore abandoned. It is concluded that inclinometry is not reliable for measuring the dynamic lumbopelvic control in any of the test positions and prior work utilising inclinometry to evaluate dynamic lumbopelvic control should be interpreted with caution.

The McKenzie method for low back pain: a systematic review of the literature with a meta-analysis approach

STUDY DESIGN AND OBJECTIVES

Meta-analysis of randomized controlled trials to evaluate the effectiveness of the McKenzie method for low back pain (LBP).

SUMMARY OF BACKGROUND DATA

The McKenzie method is a popular classification-based treatment for LBP. The faulty equation of McKenzie to extension exercises (generic McKenzie) is common in randomized trials.

METHODS

MEDLINE, EMBASE, PEDro, and LILACS were searched up to August 2003. Two independent reviewers extracted the data and assessed methodologic quality. Pooled effects were calculated among homogeneous trials using the random effects model. A sensitivity analysis excluded trials reporting on generic McKenzie.

RESULTS

Eleven trials of mostly high quality were included. McKenzie reduced pain (weighted mean difference [WMD] on a 0- to 100-point scale, -4.16 points; 95% confidence interval, -7.12 to -1.20) and disability (WMD on a 0- to 100-point scale, -5.22 points; 95% confidence interval, -8.28 to -2.16) at 1 week follow-up when compared with passive therapy for acute LBP. When McKenzie was compared with advice to stay active, a reduction in disability favored advice (WMD on a 0- to 100-point scale, 3.85 points; 95% confidence interval, 0.30 to 7.39) at 12 weeks of follow-up. Heterogeneity prevented pooling of studies on chronic LBP as well as pooling of studies included in the sensitivity analysis.

CONCLUSIONS

There is some evidence that the McKenzie method is more effective than passive therapy for acute LBP; however, the magnitude of the difference suggests the absence of clinically worthwhile effects. There is limited evidence for the use of McKenzie method in chronic LBP. The effectiveness of classification-based McKenzie is yet to be established.

Current use of lumbar traction in the management of low back pain: results of a survey of physiotherapists in the United Kingdom

OBJECTIVE

To identify the current use of traction and the types of patients, treatment parameters, and treatment modalities used in conjunction with traction.

DESIGN

Postal survey, with 4 sections: professional characteristics of respondent, current use of traction, patient selection, and treatment parameters.

SETTING

Musculoskeletal outpatient departments (private and nonprivate practitioners).

PARTICIPANTS

Random sample (N=1491) of chartered physiotherapists in the UK who work in the management of low back pain (LBP).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Descriptive analysis of information on current use and practice in applying traction.

RESULTS

A response rate of 83% (n=1239) was achieved; 41% (n=507) use lumbar traction, which is most commonly used in the management of subacute LBP patients presenting with nerve root symptoms. Treatment parameters were established for weights (5-60 kg), frequency (2-3 times weekly), and length of treatment (4 wk). In addition, traction is commonly used with other modalities (87%): mobilizations, advice, and exercise.

CONCLUSIONS

Survey results show the continued use of lumbar traction despite the recommendations of numerous guidelines. Results also clarify the types of patients and the parameters used in the application of traction.

Inter-tester reliability of a new diagnostic classification system for patients with non-specific low back pain

Most patients referred to physiotherapy with low back pain are without a precise medical diagnosis. Identification of subgroups of non-specific low back pain patients may improve clinical outcomes and research efficiency. A pathoanatomic classification system has been developed, classifying patients with non-specific low back pain into 12 different syndromes and three subcategories based on history and physical examination. The purpose of this study was to estimate the inter-tester reliability of clinical tests used as criteria for classifying patients. Ninety patients with chronic low back pain were each examined by two physiotherapists. A total of four physiotherapists conducted the assessments. Examination findings were recorded independently by the two examiners. Percentage of agreement and kappa coefficients were calculated for each category. The overall rate of agreement was 72% and the kappa coefficient was 0.62 for the mutually exclusive syndromes in the classification system. Agreement rates for each of the syndromes ranged from 74% to 100% and kappa coefficients ranged from 0.44 to 1.00. The findings suggest the inter-tester reliability of the system is acceptable. The relatively modest level of total agreement (39%) for the system as a whole might indicate that the utility of the system for general screening purposes is limited, compared with the utility in identification of particular syndromes. Due to low prevalence of positive findings in some of the syndromes, future work should focus on testing reliability on a larger sample of patients, and testing of validity and feasibility of the system.

Do primary-care clinicians think that nonspecific low back pain is one condition?

STUDY DESIGN

Postal survey. OBJECTIVES.: To determine whether Australian primary-care clinicians think that nonspecific low back pain (NSLBP) is one condition or a number of conditions (subgroups), and whether this belief influences their management of NSLBP.

SUMMARY OF BACKGROUND DATA

Most low back pain (LBP) remains a diagnostic enigma and results in approximately 80% of primary care LBP presentations being most accurately labeled as "nonspecific LBP." Manual therapy clinicians (chiropractors, osteopaths, physiotherapists) are trained to think that subgroups exist within the NSLBP population. This research sought to identify the extent to which these beliefs are widely held in primary care.

METHODS

A survey was conducted of 1,093 primary-contact clinicians from six professional disciplines (physiotherapists, manipulative physiotherapists, chiropractors, osteopaths, general medical practitioners, and musculoskeletal medicine practitioners).

RESULTS

Completed questionnaires were returned by 651 (60%) clinicians. Of the primary-contact clinicians who responded, 93% do not think NSLBP is one condition. Seventy-four percent think that it is currently possible to recognize NSLBP subgroups. Ninety-three percent treat NSLBP differently based on patterns of signs and symptoms. The proportions of clinicians who hold these views were highest for physiotherapists and manipulative physiotherapists, and smallest for general medical practitioners and musculoskeletal medicine practitioners.

CONCLUSIONS

Although assigning NSLBP patients to subgroups has not been validated, it is common in primary-care settings and influences case management. If subgroups exist within the NSLBP population, there are implications for research into the effects of treatment. Further research into the validity of subgroups is warranted.