Back complaints in the elders (BACE); design of cohort studies in primary care: an international consortium

Background

Although back complaints are common among older people, limited information is available in the literature about the clinical course of back pain in older people and the identification of older persons at risk for the transition from acute back complaints to chronic back pain.

The aim of this study is to assess the course of back complaints and identify prognostic factors for the transition from acute back complaints to chronic back complaints in older people who visit a primary health care physician.

Methods/design

The design is a prospective cohort study with one-year follow-up. There will be no interference with usual care. Patients older than 55 years who consult a primary health care physician with a new episode of back complaints will be included in this study.

Data will be collected using a questionnaire, physical examination and X-ray at baseline, and follow-up questionnaires after 6 weeks and 3, 6, 9 and 12 months.

The study 'Back Complaints in the Elders' (BACE) will take place in different countries: starting in the Netherlands, Brazil and Australia. The research groups collaborate in the BACE consortium. The design and basic objectives of the study will be the same across the studies.

Discussion

This consortium is a collaboration between different research groups, aiming to provide insight into the course of back complaints in older people and to identify prognostic factors for the transition from acute back complaints to chronic back complaints in older persons. The BACE consortium allows to investigate differences between older people with back complaints and the health care systems in the different countries and to increase the statistical power by enabling meta-analyses using the individual patient data. Additional research groups worldwide are invited to join the BACE consortium.

Transparent reporting of studies relevant to physical therapy practice

BACKGROUND

There was a clear grow, in the last 2 decades, of up to 6 fold in scientific articles that are directly relevant to physical therapy practice. However, along with this fast grow; little attention has been given to transparency when reporting research methods and results. More recently, groups of researchers around the world have made successful attempts to address this issue by creating guidelines that will help researchers not only on the preparation of manuscripts but also on making sure that important details related to design and methodology are controlled and reported.

OBJECTIVE

To present four specific reporting guidelines, which are best known as "statements".

DISCUSSION

A network named EQUATOR (Enhancing the Quality and Transparency of Health Research) was created with the main mission of providing basic principles for responsible and transparent reporting. The EQUATOR network encompasses, among others, the CONSORT statement which is related to randomized controlled trials; the PRISMA statement, which is related to systematic reviews and meta-analysis; the STROBE Statement, which is related to observational studies; and the STARD statement, which is related to reporting of accuracy of diagnostic tests. Some journals have recommended the use of these statements, while in others their use is mandatory. The goal of the use of these statements by journals is to guarantee fast decisions regarding publication and the best possible quality of reporting. Ultimately, it will help readers, including physical therapists, to make better decisions in clinical practice.

Cost-effectiveness of general practice care for low back pain: a systematic review

Care from a general practitioner (GP) is one of the most frequently utilised healthcare services for people with low back pain and only a small proportion of those with low back pain who seek care from a GP are referred to other services. The aim of this systematic review was to evaluate the evidence on cost-effectiveness of GP care in non-specific low back pain. We searched clinical and economic electronic databases, and the reference list of relevant systematic reviews and included studies to June 2010. Economic evaluations conducted alongside randomised controlled trials with at least one GP care arm were eligible for inclusion. Two reviewers independently screened search results and extracted data. Eleven studies were included; the majority of which conducted a cost-effectiveness or cost-utility analysis. Most studies investigated the cost-effectiveness of usual GP care. Adding advice, education and exercise, or exercise and behavioural counselling, to usual GP care was more cost-effective than usual GP care alone. Clinical rehabilitation and/or occupational intervention, and acupuncture were more cost-effective than usual GP care. One study investigated the cost-effectiveness of guideline-based GP care, and found that adding exercise and/or spinal manipulation was more cost-effective than guideline-based GP care alone. In conclusion, GP care alone did not appear to be the most cost-effective treatment option for low back pain. GPs can improve the cost-effectiveness of their treatment by referring their patients for additional services, such as advice and exercise, or by providing the services themselves.

A modified Delphi approach to standardize low back pain recurrence terminology

Lack of standardization of terminology in low back pain (LBP) research has significantly impeded progress in this area. The diversity in existing definitions for a 'recurrence of an episode of LBP' and 'recurrent LBP' is an important example. The variety of definitions used by researchers working in this area has prevented comparison of results between trials and made meta-analyses of this data unfeasible. The aim of this study was to use a modified Delphi approach to gain consensus on definitions for a 'recurrence of an episode of LBP' (e.g. outcome event) and for 'recurrent LBP' (e.g. patient population). Existing definitions for both constructs were classified into the main features comprising the definition (e.g. 'duration of pain') and the items that defined each feature (e.g. 'pain lasting at least 24 h'). In each round, participants were asked to rate the importance of each feature to a definition of a 'recurrence of an episode of LBP', and a definition of 'recurrent LBP' and rank the items (defining each feature) in order of decreasing importance. Forty-six experts in LBP research, from nine different countries, participated in this study. Four rounds were completed with responses rates of 94, 91, 83, and 97% in rounds 1, 2, 3, and 4, respectively. Consensus definitions were reached in both areas with 95% of panel members supporting the definition of a 'recurrence of an episode of LBP' and 92% of panel members supporting the definition of 'recurrent LBP'. Future research is necessary to evaluate these definitions.

Prevalence of sleep disturbance in patients with low back pain

Low back pain (LBP) is a common health condition that is often associated with disability, psychological distress and work loss. Worldwide, billions of dollars are expended each year trying to manage LBP, often with limited success. Recently, some researchers have reported that LBP patients also report sleep disturbance as a result of their LBP. However, as most of this evidence was obtained from highly selected groups of patients or from studies with small samples, high quality data on prevalence of sleep disturbance for patients with LBP are lacking. It is also unclear whether sleep disturbance is more likely to be reported by patients with recent-onset LBP than by patients with persistent LBP. Finally, it is not known whether high pain intensity, the most relevant condition-specific variable, is associated with higher rates of reported sleep disturbance. The present study aimed to determine the prevalence of reported sleep disturbance in patients with LBP. In addition, we aimed to determine whether sleep disturbance was associated with the duration of back pain symptoms and whether pain intensity was associated with reported sleep disturbance. Data from 1,941 patients obtained from 13 studies conducted by the authors or their colleagues between 2001 and 2009 were used to determine the prevalence of sleep disturbance. Logistic regression analyses explored associations between sleep disturbance, the duration of low back symptoms and pain intensity. The estimated prevalence of sleep disturbance was 58.7% (95% CI 56.4-60.7%). Sleep disturbance was found to be dependent on pain intensity, where each increase by one point on a ten-point visual analogue scale (VAS) was associated with a 10% increase in the likelihood of reporting sleep disturbance. Our findings indicate that sleep disturbance is common in patients with LBP. In addition, we found that the intensity of back pain was only weakly associated with sleep disturbance, suggesting that other factors contribute to sleep problems for LBP patients.

Responsiveness of the 24-, 18- and 11-item versions of the Roland Morris Disability Questionnaire

Several versions of the 24-item Roland Morris Disability Questionnaire (RMDQ) have been proposed; however, their responsiveness has not been extensively explored. The objective of this study was to compare the responsiveness of four versions of the RMDQ. Perceived disability was measured using the 24-item, two 18-item and an 11-item RMDQ on 1,069 low back pain patients from six randomised controlled trials. Responsiveness was calculated using effect size, Guyatt's responsiveness index (GRI) and receiver operating characteristics (ROC) curves. Effect size analyses showed that both 18-item versions of the RMDQ were superior to the 24- and 11-item versions of the RMDQ. GRI showed that the 24- and 18-item versions of the RMDQ were similar but more responsive than the 11-item. ROC curves revealed that the 11-item was less responsive than the other three versions, which had similar responsiveness. The results of this study demonstrate that the 24-item and both 18-item versions of the RMDQ have similar responsiveness with all having superior responsiveness to the 11-item.

The patient-specific functional scale is more responsive than the Roland Morris disability questionnaire when activity limitation is low

The primary objective of this study was to determine which questionnaire, the Roland Morris disability questionnaire (RMDQ) or the patient-specific functional scale (PSFS), was better at detecting change in activity limitation in a large cohort of patients with low back pain undergoing rehabilitation. A secondary aim was to determine if the responsiveness of the questionnaires was influenced by the patient's level of activity limitation at baseline. Responsiveness statistics, including effect size statistics, Pearson's r correlations and receiver operative characteristic (ROC) curve analysis were used to determine ability to detect change in activity limitation on 831 patients with low back pain. Data were analysed at two time points; directly after treatment (termed short-term) and several weeks post-treatment (termed mid-term). The data were subsequently re-analysed on sub-sets of the full cohort according to the level of activity limitation from RMDQ baseline scores. In the total cohort we found that the PSFS was more responsive than the RMDQ; however, in the subgroup with high activity limitation this pattern was not observed. This is true for time points up to 6 months post-treatment. In conclusion, the RMDQ and PSFS both demonstrate good responsiveness according to the definitions given in previous guidelines. The PSFS is more responsive than the RMDQ for patients with low levels of activity limitation but not for patients with high levels of activity limitation.

The effectiveness of the McKenzie method in addition to first-line care for acute low back pain: a randomized controlled trial

BACKGROUND

Low back pain is a highly prevalent and disabling condition worldwide. Clinical guidelines for the management of patients with acute low back pain recommend first-line treatment consisting of advice, reassurance and simple analgesics. Exercise is also commonly prescribed to these patients. The primary aim of this study was to evaluate the short-term effect of adding the McKenzie method to the first-line care of patients with acute low back pain.

METHODS

A multi-centre randomized controlled trial with a 3-month follow-up was conducted between September 2005 and June 2008. Patients seeking care for acute non-specific low back pain from primary care medical practices were screened. Eligible participants were assigned to receive a treatment programme based on the McKenzie method and first-line care (advice, reassurance and time-contingent acetaminophen) or first-line care alone, for 3 weeks. Primary outcome measures included pain (0-10 Numeric Rating Scale) over the first seven days, pain at 1 week, pain at 3 weeks and global perceived effect (-5 to 5 scale) at 3 weeks. Treatment effects were estimated using linear mixed models.

RESULTS

One hundred and forty-eight participants were randomized into study groups, of whom 138 (93%) completed the last follow-up. The addition of the McKenzie method to first-line care produced statistically significant but small reductions in pain when compared to first-line care alone: mean of -0.4 points (95% confidence interval, -0.8 to -0.1) at 1 week, -0.7 points (95% confidence interval, -1.2 to -0.1) at 3 weeks, and -0.3 points (95% confidence interval, -0.5 to -0.0) over the first 7 days. Patients receiving the McKenzie method did not show additional effects on global perceived effect, disability, function or on the risk of persistent symptoms. These patients sought less additional health care than those receiving only first-line care (P = 0.002).

CONCLUSIONS

When added to the currently recommended first-line care of acute low back pain, a treatment programme based on the McKenzie method does not produce appreciable additional short-term improvements in pain, disability, function or global perceived effect. However, the McKenzie method seems to reduce health utilization although it does not reduce patient's risk of developing persistent symptoms.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12605000032651.

A randomised clinical trial of a comprehensive exercise program for chronic whiplash: trial protocol

BACKGROUND

Whiplash is the most common injury following a motor vehicle accident. Approximately 60% of people suffer persistent pain and disability six months post injury. Two forms of exercise; specific motor relearning exercises and graded activity, have been found to be effective treatments for this condition. Although the effect sizes for these exercise programs, individually, are modest, pilot data suggest much larger effects on pain and disability are achieved when these two treatments are combined. The aim of this study is to investigate the effectiveness and cost-effectiveness of this comprehensive exercise approach for chronic whiplash.

METHODS/DESIGN

A multicentre randomised controlled trial will be conducted. One hundred and seventy-six participants with chronic grade I to II whiplash will be recruited in Sydney and Brisbane, Australia. All participants will receive an educational booklet on whiplash and in addition, those randomised to the comprehensive exercise group (specific motor relearning and graded activity exercises) will receive 20 progressive and individually-tailored, 1 hour exercise sessions over a 12 week period (specific motor relearning exercises: 8 sessions over 4 weeks; graded activity: 12 sessions over 8 weeks). The primary outcome to be assessed is pain intensity. Other outcomes of interest include disability, health-related quality of life and health service utilisation. Outcomes will be measured at baseline, 14 weeks, 6 months and 12 months by an assessor who is blinded to the group allocation of the subjects. Recruitment is due to commence in late 2009.

DISCUSSION

The successful completion of this trial will provide evidence on the effectiveness and cost-effectiveness of a simple treatment for the management of chronic whiplash.

TRIAL REGISTRATION

ACTRN12609000825257.

How do we define the condition 'recurrent low back pain'? A systematic review

Recurrent low back pain (recurrent LBP) is a common condition, however, it is unclear if uniform definitions are used in studies investigating the prevalence and management of this condition. The aim of this systematic review was to identify how recurrent LBP is defined in the literature. A literature search was performed on MEDLINE, EMBASE, CINAHL, AMED, and PEDro. Studies were considered eligible if they investigated a cohort of subjects with recurrent LBP or if they were measuring the prevalence of recurrent LBP. Two independent reviewers assessed inclusion of studies and extracted definitions of recurrent LBP. Forty-three studies met the inclusion criteria. The majority of studies (63%) gave an explicit definition of recurrent LBP; however, the definitions varied greatly and only three definitions for recurrent LBP were used by more than one study. The most common feature given as part of the definition was the frequency of previous episodes of low back pain. Only 8% (3/36) of studies used previously recommended definitions for recurrent LBP. Large variation exists in definitions of recurrent LBP used in the literature, making interpretation of prevalence rates and treatment outcomes very difficult. Achieving consensus among experts in this area is required.

Do psychological characteristics predict response to exercise and advice for subacute low back pain?

OBJECTIVE

To determine whether psychological characteristics predict outcome and/or response to physiotherapist-directed exercise- or advice-based treatment of subacute low back pain.

METHODS

We conducted a secondary analysis of a factorial, placebo-controlled trial (n = 259). The psychological characteristics were catastrophizing, coping, pain self-efficacy, fear of injury/movement, depression, anxiety, and stress. We used mixed models to predict pain and function outcomes (both scored on a 0-10 scale). The models include a term for treatment group, a term for the psychological characteristic (which tested prediction of outcome), and an interaction term between the treatment group and psychological characteristic (which tested treatment effect modification). To aid the interpretation of the magnitude of the effect modification, we calculated the change in outcome for a 1 SD increase of the baseline score of the putative effect modifier. A >/=1.5-point change of the outcome of interest per 1 SD change of putative effect modifier was regarded as clinically important.

RESULTS

All of the psychological characteristics except coping predicted outcome, but none appeared to be important treatment effect modifiers. Only 5 of the 56 tests of treatment modification were statistically significant, and none of the 95% confidence intervals (95% CIs) for the interactions included clinically important effects. For example, a 1 SD higher baseline level of anxiety was associated with a 0.62 (95% CI 0.10, 1.15) additional effect of exercise on function at 52 weeks.

CONCLUSION

Most of the psychological characteristics we tested predicted outcome, but none predicted response to physiotherapist-guided exercise and/or advice.

A randomized controlled trial of tai chi for long-term low back pain (TAI CHI): study rationale, design, and methods

Background

Low back pain persisting for longer than 3 months is a common and costly condition for which many current treatments have low-moderate success rates at best. Exercise is among the more successful treatments for this condition, however, the type and dosage of exercise that elicits the best results is not clearly defined. Tai chi is a gentle form of low intensity exercise that uses controlled movements in combination with relaxation techniques and is currently used as a safe form of exercise for people suffering from other chronic pain conditions such as arthritis. To date, there has been no scientific evaluation of tai chi as an intervention for people with back pain. Thus the aim of this study will be to examine the effects of a tai chi exercise program on pain and disability in people with long-term low back pain.

Methods and design

The study will recruit 160 healthy individuals from the community setting to be randomised to either a tai chi intervention group or a wait-list control group. Individuals in the tai chi group will attend 2 tai chi sessions (40 minutes)/week for 8 weeks followed by 1 tai chi session/week for 2 weeks. The wait-list control will continue their usual health care practices and have the opportunity to participate in the tai chi program once they have completed the follow-up assessments. The primary outcome will be bothersomeness of back symptoms measured with a 0–10 numerical rating scale. Secondary outcomes include, self-reports of pain-related disability, health-related quality of life and global perceived effect of treatment. Statistical analysis of primary and secondary outcomes will be based on the intention to treat principle. Linear mixed models will be used to test for the effect of treatment on outcome at 10 weeks follow up. This trial has received ethics approval from The University of Sydney Human Research Ethics Committee. HREC Approval No.10452

Discussion

This study will be the first trial in this area and the information on its effectiveness will allow patients, clinicians and treatment funders to make informed choices regarding this treatment.

Trial Registration

This trial has been registered with Australian New Zealand Clinical Trials Registry. ACTRN12608000270314

Changes in recruitment of transversus abdominis correlate with disability in people with chronic low back pain

OBJECTIVES

Although motor control exercises have been shown to be effective in the management of low back pain (LBP) the mechanism of action is unclear. The current study investigated the relationship between the ability to recruit transversus abdominis and clinical outcomes of participants in a clinical trial.

METHODS

Ultrasonography was used to assess the ability to recruit transversus abdominis in a nested design: a sample of 34 participants with chronic LBP was recruited from participants in a randomised controlled trial comparing the efficacy of motor control exercise, general exercise and spinal manipulative therapy. Perceived recovery, function, disability and pain were also assessed.

RESULTS

Participants with chronic LBP receiving motor control exercise had a greater improvement in recruitment of transversus abdominis (7.8%) than participants receiving general exercise (4.9% reduction) or spinal manipulative therapy (3.7% reduction). The effect of motor control exercise on pain reduction was greater in participants who had a poor ability to recruit transversus abdominis at baseline. There was a significant, moderate correlation between improved recruitment of transversus abdominis and a reduction in disability (r = -0.35; 95% CI 0.02 to 0.62).

CONCLUSION

These data provide some support for the hypothesised mechanism of action of motor control exercise and suggest that the treatment may be more effective in those with a poor ability to recruit transversus abdominis.

An investigation of the reproducibility of ultrasound measures of abdominal muscle activation in patients with chronic non-specific low back pain

Ultrasound (US) measures are used by clinicians and researchers to evaluate improvements in activity of the abdominal muscles in patients with low back pain. Studies evaluating the reproducibility of these US measures provide some information; however, little is known about the reproducibility of these US measures over time in patients with low back pain. The objectives of this study were to estimate the reproducibility of ultrasound measurements of automatic activation of the lateral abdominal wall muscles using a leg force task in patients with chronic low back pain. Thirty-five participants from an existing randomised, blinded, placebo-controlled trial participated in the study. A reproducibility analysis was undertaken from all patients using data collected at baseline and after treatment. The reproducibility of measurements of thickness, muscle activation (thickness changes) and muscle improvement/deterioration after intervention (differences in thickness changes from single images made before and after treatment) was analysed. The reproducibility of static images (thickness) was excellent (ICC(2,1) = 0.97, 95% CI = 0.96-0.97, standard error of the measurement (SEM) = 0.04 cm, smallest detectable change (SDC) = 0.11 cm), the reproducibility of thickness changes was moderate (ICC(2,1) = 0.72, 95% CI 0.65-0.76, SEM = 15%, SDC 41%), while the reproducibility of differences in thickness changes from single images with statistical adjustment for duplicate measures was poor (ICC(2,1) = 0.44, 95% CI 0.33-0.58, SEM = 21%, SDC = 66.5%). Improvements in the testing protocol must be performed in order to enhance reproducibility of US as an outcome measure for abdominal muscle activation.

Analgesic effects of treatments for non-specific low back pain: a meta-analysis of placebo-controlled randomized trials

OBJECTIVE

Estimates of treatment effects reported in placebo-controlled randomized trials are less subject to bias than those estimates provided by other study designs. The objective of this meta-analysis was to estimate the analgesic effects of treatments for non-specific low back pain reported in placebo-controlled randomized trials.

METHODS

Medline, Embase, Cinahl, PsychInfo and Cochrane Central Register of Controlled Trials databases were searched for eligible trials from earliest records to November 2006. Continuous pain outcomes were converted to a common 0-100 scale and pooled using a random effects model.

RESULTS

A total of 76 trials reporting on 34 treatments were included. Fifty percent of the investigated treatments had statistically significant effects, but for most the effects were small or moderate: 47% had point estimates of effects of <10 points on the 100-point scale, 38% had point estimates from 10 to 20 points and 15% had point estimates of >20 points. Treatments reported to have large effects (>20 points) had been investigated only in a single trial.

CONCLUSIONS

This meta-analysis revealed that the analgesic effects of many treatments for non-specific low back pain are small and that they do not differ in populations with acute or chronic symptoms.

Motor control or graded activity exercises for chronic low back pain? A randomised controlled trial

Background

Chronic low back pain remains a major health problem in Australia and around the world. Unfortunately the majority of treatments for this condition produce small effects because not all patients respond to each treatment. It appears that only 25–50% of patients respond to exercise. The two most popular types of exercise for low back pain are graded activity and motor control exercises. At present however, there are no guidelines to help clinicians select the best treatment for a patient. As a result, time and money are wasted on treatments which ultimately fail to help the patient.

Methods

This paper describes the protocol of a randomised clinical trial comparing the effects of motor control exercises with a graded activity program in the treatment of chronic non specific low back pain. Further analysis will identify clinical features that may predict a patient's response to each treatment. One hundred and seventy two participants will be randomly allocated to receive either a program of motor control exercises or graded activity. Measures of outcome will be obtained at 2, 6 and 12 months after randomisation. The primary outcomes are: pain (average pain intensity over the last week) and function (patient-specific functional scale) at 2 and 6 months. Potential treatment effect modifiers will be measured at baseline.

Discussion

This trial will not only evaluate which exercise approach is more effective in general for patients will chronic low back pain, but will also determine which exercise approach is best for an individual patient.

Trial registration number

ACTRN12607000432415

Imperfect placebos are common in low back pain trials: a systematic review of the literature

The placebo is an important tool to blind patients to treatment allocation and therefore minimise some sources of bias in clinical trials. However, placebos that are improperly designed or implemented may introduce bias into trials. The purpose of this systematic review was to evaluate the adequacy of placebo interventions used in low back pain trials. Electronic databases were searched systematically for randomised placebo-controlled trials of conservative interventions for low back pain. Trial selection and data extraction were performed by two reviewers independently. A total of 126 trials using over 25 different placebo interventions were included. The strategy most commonly used to enhance blinding was the provision of structurally equivalent placebos. Adequacy of blinding was assessed in only 13% of trials. In 20% of trials the placebo intervention was a potentially genuine treatment. Most trials that assessed patients' expectations showed that the placebo generated lower expectations than the experimental intervention. Taken together, these results demonstrate that imperfect placebos are common in low back pain trials; a result suggesting that many trials provide potentially biased estimates of treatment efficacy. This finding has implications for the interpretation of published trials and the design of future trials. Implementation of strategies to facilitate blinding and balance expectations in randomised groups need a higher priority in low back pain research.

Patient and clinician treatment preferences do not moderate the effect of exercise treatment in chronic whiplash-associated disorders

An issue that arises when selecting therapy is whether patient or clinician preferences for treatment moderate the effect of treatment. To evaluate this question we conducted a secondary analysis of the results of a randomized controlled trial of exercise treatment of chronic whiplash. Immediately prior to randomization, treatment preference ratings were collected from each patient and from the physiotherapist who assessed each patient. Patients were then randomized to receive advice alone or exercise and advice with the primary treatment outcomes of pain and function measured immediately after conclusion of treatment. Treatment effect modification was evaluated with a treatment group by preference interaction term in the regression analyses. The analysis revealed that neither patient nor therapist treatment preferences moderated the effect of exercise treatment for chronic whiplash. The interaction effect of treatment group by patient preference was 0.1 (-0.3 to 0.5, p=0.68) on the 0-10 pain intensity scale and -0.1 (-0.5 to 0.3, p=0.64) on the 0-10 function scale. The interaction effect of treatment group by therapist preference was 0.0 (-0.3 to 0.4, p=0.786) on the 0-10 pain intensity scale and -0.2 (-0.4 to 0.1, p=0.296) on the 0-10 function scale. Our findings do not provide evidence that patient or therapist treatment preferences moderate the effect of exercise treatment for chronic whiplash.

Assessment of diclofenac or spinal manipulative therapy, or both, in addition to recommended first-line treatment for acute low back pain: a randomised controlled trial

BACKGROUND

We aimed to investigate whether the addition of non-steroidal anti-inflammatory drugs or spinal manipulative therapy, or both, would result in faster recovery for patients with acute low back pain receiving recommended first-line care.

METHODS

240 patients with acute low back pain who had seen their general practitioner and had been given advice and paracetamol were randomly allocated to one of four groups in our community-based study: diclofenac 50 mg twice daily and placebo manipulative therapy (n=60); spinal manipulative therapy and placebo drug (n=60); diclofenac 50 mg twice daily and spinal manipulative therapy (n=60); or double placebo (n=60). The primary outcome was days to recovery from pain assessed by survival curves (log-rank test) in an intention-to-treat analysis. This trial was registered with the Australian Clinical Trials Registry, ACTRN012605000036617.

FINDINGS

Neither diclofenac nor spinal manipulative therapy appreciably reduced the number of days until recovery compared with placebo drug or placebo manipulative therapy (diclofenac hazard ratio 1.09, 95% CI 0.84-1.42, p=0.516; spinal manipulative therapy hazard ratio 1.01, 95% CI 0.77-1.31, p=0.955). 237 patients (99%) either recovered or were censored 12 weeks after randomisation. 22 patients had possible adverse reactions including gastrointestinal disturbances, dizziness, and heart palpitations. Half of these patients were in the active diclofenac group, the other half were taking placebo. One patient taking active diclofenac had a suspected hypersensitivity reaction and ceased treatment.

INTERPRETATION

Patients with acute low back pain receiving recommended first-line care do not recover more quickly with the addition of diclofenac or spinal manipulative therapy.

The effect of neoprene shorts on leg proprioception in Australian football players

Our purpose was to assess the effect of wearing close-fitting neoprene shorts on swinging leg movement discrimination (MD) scores in elite level Australian Football players. Twenty players had their swinging leg MD assessed using the active movement extent discrimination apparatus (AMEDA), once wearing close-fitting neoprene and once wearing loose-fitting running shorts. Subjects were randomly allocated to one of the shorts conditions prior to repeating the test in the other condition. The AMEDA was used to assess the accuracy at which subjects judge the extent of a standing backward swinging leg movement corresponding to the late swing early stance phase of running. Each subject performed 40 movements made to one of five randomly set physical limits, and without the aid of vision made a judgment as to the perceived limit position. From the accuracy of these judgments, a movement discrimination (MD) score was calculated for each subject under each condition. Subjects were grouped as having low or high neuromuscular control, or ability to use proprioception when controlling active movements without vision, based on their loose-shorts MD score. Analysis was performed on the MD scores obtained for each limb from subjects in the two groups, under the two shorts-wearing conditions. There was no main effect of wearing close-fitting shorts when the cohort was treated as a whole. A significant interaction effect was obtained (F=17.027, p=0.0006) whereby the mean MD score of the low neuromuscular control ability group was improved when wearing neoprene shorts but was reduced for the high ability group. Wearing close-fitting neoprene shorts has a beneficial effect on leg swing judgment accuracy in subjects with low neuromuscular control ability. Conversely, leg swing judgment accuracy for subjects with high ability was reduced by wearing neoprene shorts.

Psychometric characteristics of the Brazilian-Portuguese versions of the Functional Rating Index and the Roland Morris Disability Questionnaire

STUDY DESIGN

Translation, cross-cultural adaptation and psychometric testing of self-report outcome measurements.

OBJECTIVES

The aims of this study were to adapt the Functional Rating Index (FRI) to Brazilian-Portuguese and to test the psychometric properties of this new questionnaire and the Brazilian-Roland Morris Disability Questionnaire (RMDQ).

SUMMARY OF BACKGROUND DATA

Self-report measures are commonly used in clinical practice and in research studies. Most existing questionnaires were developed in English and there is only 1 Brazilian-Portuguese cross-cultural adaptation of a spine outcome measure.

METHODS

The FRI was translated and adapted into Brazilian-Portuguese according to the Guidelines for the process of cross-cultural adaptation of self report measures. The Brazilian-Portuguese FRI and RMDQ were tested for internal consistency, reliability, ceiling and floor effects, construct validity, and responsiveness in 140 low back pain (LBP) patients.

RESULTS

A very high level of internal consistency (Cronbach's alpha = 0.92) and reliability [ICC = 0.95 (95% confidence interval, 0.93-0.97)] was shown for both instruments. The FRI and RMDQ were highly correlated (r = 0.80), while both the FRI and RMDQ were moderately correlated with pain at baseline (r = 0.67 and 0.55, respectively). No ceiling or floor effects were detected; however, the responsiveness of both questionnaires was quite small (RMDQ ES = 0.10 [84% confidence interval, 0.04-0.16] and FRI ES = 0.18 [84% confidence interval, 0.11-0.24]).

CONCLUSION

The results of this study indicate that the Brazilian-Portuguese versions of the FRI and RMDQ are reliable and valid instruments for the measurement of disability in Brazilian-Portuguese-speaking patients with LBP presenting for physiotherapy treatment. Both instruments are suitable for use in clinical practice and research studies.

Systematic review of tests to identify the disc, SIJ or facet joint as the source of low back pain

Clinical practice guidelines state that the tissue source of low back pain cannot be specified in the majority of patients. However, there has been no systematic review of the accuracy of diagnostic tests used to identify the source of low back pain. The aim of this systematic review was therefore to determine the diagnostic accuracy of tests available to clinicians to identify the disc, facet joint or sacroiliac joint (SIJ) as the source of low back pain. MEDLINE, EMBASE and CINAHL were searched up to February 2006 with citation tracking of eligible studies. Eligible studies compared index tests with an appropriate reference test (discography, facet joint or SIJ blocks or medial branch blocks) in patients with low back pain. Positive likelihood ratios (+LR) > 2 or negative likelihood ratios (-LR) < 0.5 were considered informative. Forty-one studies of moderate quality were included; 28 investigated the disc, 8 the facet joint and 7 the SIJ. Various features observed on MRI (high intensity zone, endplate changes and disc degeneration) produced informative +LR (> 2) in the majority of studies increasing the probability of the disc being the low back pain source. However, heterogeneity of the data prevented pooling. +LR ranged from 1.5 to 5.9, 1.6 to 4.0, and 0.6 to 5.9 for high intensity zone, disc degeneration and endplate changes, respectively. Centralisation was the only clinical feature found to increase the likelihood of the disc as the source of pain: +LR = 2.8 (95%CI 1.4-5.3). Absence of degeneration on MRI was the only test found to reduce the likelihood of the disc as the source of pain: -LR = 0.21 (95%CI 0.12-0.35). While single manual tests of the SIJ were uninformative, their use in combination was informative with +LR of 3.2 (95%CI 2.3-4.4) and -LR of 0.29 (95%CI 0.12-0.35). None of the tests for facet joint pain were found to be informative. The results of this review demonstrate that tests do exist that change the probability of the disc or SIJ (but not the facet joint) as the source of low back pain. However, the changes in probability are usually small and at best moderate. The usefulness of these tests in clinical practice, particularly for guiding treatment selection, remains unclear.

Self-report outcome measures for low back pain: searching for international cross-cultural adaptations

STUDY DESIGN

Systematic review.

OBJECTIVES

To describe the available cross-cultural adaptations of low back pain (LBP) self-report outcome measures and the psychometric testing that has occurred for each adaptation.

SUMMARY OF BACKGROUND DATA

Self-report measures are commonly used in clinical practice and in research studies. Most existing questionnaires were developed in English, and it is not clear how many have been adapted to other languages.

METHODS

Two different searches on MEDLINE, EMBASE, CINAHL, and LILACS were performed. The first search identified questionnaires specifically designed for patients with LBP. The second search combined the name of the questionnaire with 35 different languages in order to locate cross-cultural adaptations of the questionnaire. Data on the psychometric testing of the translated questionnaires were extracted.

RESULTS

Forty questionnaires were identified, only 15 of which had been adapted to a new language. Only 19 of the 35 different languages we searched for were represented in the search results. From 1400 possible adaptations, only 61 have been completed. Psychometric testing of the adapted questionnaires was quite variable and in general suboptimal with testing usually restricted to an assessment of reliability and construct validity.

CONCLUSIONS

There is a clear need for further cross-cultural adaptation of LBP self-report measures and for greater attention to the quality of psychometric evaluation of adapted questionnaires. Without appropriately adapted measures, the clinical management of LBP patients who do not speak English is potentially compromised.

Study protocol: the effects of work-site exercise on the physical fitness and work-ability of older workers

Background

Older workers have a higher rate and cost of injury than younger workers and with a rapidly ageing work force there is a need to identify strategies to address this problem. Older workers are less physically active and fit than younger workers and so have reduced work ability. The reduced work ability means they are more likely to be fatigued at work and so at greater risk of injury. Exercise could potentially assist this problem. Exercise training has been previously shown to improve fitness in older people however there has been no evaluation of workplace exercise program for older workers. We do not know if the programs are feasible and can improve the fitness and work ability of older workers. We have designed a randomised controlled trial to evaluate whether exercise improves fitness and perceived work-ability of older workers.

Methods/Design

This paper describes the protocol for a trial examining the effects of a 12-week physical training program in workers over the age of 45. Participants will be randomized to an exercise or no-intervention control group. The primary outcomes are cardiorespiratory endurance, lifting capacity, upper and lower limb strength and perceived work-ability.

Discussion

This trial will test the feasibility of implementing a worksite-based exercise program as a means of improving the physical fitness and work-ability of older workers performing physically demanding work. If we demonstrate the feasibility of the program we will conduct a larger trial that additionally measures injury outcomes.

Risk factors for neck pain in office workers: a prospective study

Background

Persisting neck pain is common in society. It has been reported that the prevalence of neck pain in office workers is much higher than in the general population. The costs to the worker, employer and society associated with work-related neck pain are known to be considerable and are escalating. The factors that place office workers at greater risk of developing neck pain are not understood. The aim of this study is to investigate the incidence and risk factors of work-related neck pain in Australian office workers.

Methods/design

We will conduct a prospective cohort study. A cohort of office workers without neck pain will be followed over a 12 month period, after baseline measurement of potential risk factors. The categories of risk factors being evaluated are physical (cervical spine posture, range of movement, muscle endurance and exercise frequency), demographic (age, sex), work environment (sitting duration, frequency of breaks) and psychosocial (psychological distress and psychosocial work factors). Cox regression analysis will be used to identify risk factors associated with work-related neck pain, and will be expressed as hazard ratios with 95% confidence intervals. The data will also enable the incidence of neck pain in this population to be estimated.

Discussion

In addition to clarifying the magnitude of this occupational health problem these data could inform policy in workplaces and provide the basis for primary prevention of neck pain in office workers, targeting the identified risk factors.

Randomized controlled trial of exercise for chronic whiplash-associated disorders

Whiplash-associated disorders are common and incur considerable expense in social and economic terms. There are no known effective treatments for those people whose pain and disability persist beyond 3 months. We conducted a randomized, assessor-blinded, controlled trial at two centres in Australia. All participants received 3 advice sessions. In addition the experimental group participated in 12 exercise sessions over 6 weeks. Primary outcomes were pain intensity, pain bothersomeness and function measured at 6 weeks and 12 months. Exercise and advice was more effective than advice alone at 6 weeks for all primary outcomes but not at 12 months. The effect of exercise on the 0-10 pain intensity scale was -1.1 (95%CI -1.8 to -0.3, p=0.005) at 6 weeks and -0.2 (0.6 to -1.0, p=0.59) at 12 months; on the bothersomeness scale the effect was -1.0 (-1.9 to -0.2, p=0.003) at 6 weeks and 0.3 (-0.6 to 1.3, p=0.48) at 12 months. The effect on function was 0.9 (0.3 to 1.6, p=0.006) at 6 weeks and 0.6 (-0.1 to 1.4, p=0.10) at 12 months. High levels of baseline pain intensity were associated with greater treatment effects at 6 weeks and high levels of baseline disability were associated with greater treatment effects at 12 months. In the short-term exercise and advice is slightly more effective than advice alone for people with persisting pain and disability following whiplash. Exercise is more effective for subjects with higher baseline pain and disability.

Low back pain investigations and prognosis: a review

Low back pain is reviewed in terms of when investigations are useful and its clinical course. Despite the extensive evaluation of the accuracy of investigations such as radiography, magnetic resonance imaging, and myelography, there is a surprising dearth of research to inform their use in primary care. There is no clear evidence on which to base judgments for selection of appropriate tests to confirm or exclude low back pain pathology. It appears that investigations are rarely necessary for low back pain. Specific investigations should be ordered to identify a particular pathology but should not be ordered routinely for general screening. In the absence of pathology, low back pain and its associated disability improve rapidly in the first weeks after onset, but, in contradiction to all guidelines, both commonly persist and the best evidence suggests that recurrences are common.

Development and psychometric testing of Korean language versions of 4 neck pain and disability questionnaires

STUDY DESIGN

Cohort study.

OBJECTIVES

To develop and establish the psychometric properties of Korean versions of 4 neck pain and disability questionnaires: the Neck Disability Index, Neck Pain and Disability Scale, Functional Rating Index, and Short Form McGill Pain Questionnaire (SFMPQ).

SUMMARY OF BACKGROUND DATA

To our knowledge, there are no published Korean language neck pain and disability measures.

METHODS

Versions of each questionnaire in idiomatic modern Korean were developed with a process involving initial independent translation, synthesis of the translations, independent back translation, and review by an expert committee to achieve equivalence with the original English. Psychometric testing of the questionnaires with 261 subjects was undertaken to examine test-retest reliability, internal consistency, discriminative validity, and longitudinal construct validity.

RESULTS

Test-retest reliability of the translated versions of the 3 disability questionnaires was excellent (intraclass correlation coefficient[2,1] = 0.86-0.90). High internal consistency was found in the 3 disability questionnaires (Cronbach-alpha ranged from alpha = 0.88 for the Functional Rating Index to alpha = 0.96 for the Neck Pain and Disability Scale, and 0.82 for the SFMPQ). The visual analog scale subscale of the SFMPQ was the most responsive of the subscales (effect size = 1.44, standardized response mean = 1.37). The visual analog scale was also the most responsive pain and disability index in internal responsiveness analysis, although disability indexes showed marginally better responsiveness when compared with external standards. No floor or ceiling effects were observed.

CONCLUSIONS

We conclude that the questionnaires were successfully translated and show acceptable measurement properties, and, as such, are suitable for use in clinical and research applications.

The effect of motor control exercise versus placebo in patients with chronic low back pain [ACTRN012605000262606]

BACKGROUND

While one in ten Australians suffer from chronic low back pain this condition remains extremely difficult to treat. Many contemporary treatments are of unknown value. One potentially useful therapy is the use of motor control exercise. This therapy has a biologically plausible effect, is readily available in primary care and it is of modest cost. However, to date, the efficacy of motor control exercise has not been established.

METHODS

This paper describes the protocol for a clinical trial comparing the effects of motor control exercise versus placebo in the treatment of chronic non-specific low back pain. One hundred and fifty-four participants will be randomly allocated to receive an 8-week program of motor control exercise or placebo (detuned short wave and detuned ultrasound). Measures of outcomes will be obtained at follow-up appointments at 2, 6 and 12 months after randomisation. The primary outcomes are: pain, global perceived effect and patient-generated measure of disability at 2 months and recurrence at 12 months.

DISCUSSION

This trial will be the first placebo-controlled trial of motor control exercise. The results will inform best practice for treating chronic low back pain and prevent its occurrence.

The McKenzie Method for the management of acute non-specific low back pain: design of a randomised controlled trial [ACTRN012605000032651]

Background

Low back pain (LBP) is a major health problem. Effective treatment of acute LBP is important because it prevents patients from developing chronic LBP, the stage of LBP that requires costly and more complex treatment.

Physiotherapists commonly use a system of diagnosis and exercise prescription called the McKenzie Method to manage patients with LBP. However, there is insufficient evidence to support the use of the McKenzie Method for these patients. We have designed a randomised controlled trial to evaluate whether the addition of the McKenzie Method to general practitioner care results in better outcomes than general practitioner care alone for patients with acute LBP.

Methods/design

This paper describes the protocol for a trial examining the effects of the McKenzie Method in the treatment of acute non-specific LBP. One hundred and forty eight participants who present to general medical practitioners with a new episode of acute non-specific LBP will be randomised to receive general practitioner care or general practitioner care plus a program of care based on the McKenzie Method. The primary outcomes are average pain during week 1, pain at week 1 and 3 and global perceived effect at week 3.

Discussion

This trial will provide the first rigorous test of the effectiveness of the McKenzie Method for acute non-specific LBP.

Responsiveness of pain, disability, and physical impairment outcomes in patients with low back pain

STUDY DESIGN

Cohort study.

OBJECTIVE

To conduct a head-to-head comparison of the responsiveness of pain, disability, and physical impairment measures in patients with low back pain.

SUMMARY OF BACKGROUND DATA

Pain, disability, and physical impairment measures are routinely measured in clinical practice and clinical research. However, to date, a head-to-head comparison has not been performed.

METHODS

A numerical pain scale (0-10), the 24-item and 2 modified 18-item versions of the Roland Morris questionnaire, the patient specific functional scale, and physical impairment measures were completed by 155 patients with low back pain at baseline and then again after 6 weeks together with an 11-point global perceived effect scale. Responsiveness was evaluated by using effect sizes and t tests, correlating the change scores for each outcome with the global perceived effect score and by calculating the Guyatt responsiveness index.

RESULTS

The most responsive outcome proved to be the patient specific functional scale (effect size = 1.6), followed by the numerical pain scale (effect size = 1.3) and 24-item Roland Morris questionnaire (effect size = 0.8). The responsiveness of the two 18-item Roland Morris versions was equal to the 24-item version. However, the physical impairment measures were not very responsive (effect size 0.1-0.6). The ranking of the responsiveness indices was consistent across all statistical analyses.

CONCLUSIONS

Physical impairments are routinely measured in clinical practice and clinical research, but the lower responsiveness indicates that this approach is not optimal. Our findings suggest that more emphasis should be placed on change in pain and disability scores than on change in physical impairments.

Effective physical treatment for chronic low back pain

It is now feasible to adopt an evidence-based approach when providing physical treatment for patients with chronic LBP. A summary of the efficacy of a range of physical treatments is provided in Table 1. The evidence-based primary care options are exercise, laser, massage, and spinal manipulation; however, the latter three have small or transient effects that limit their value as therapies for chronic LBP. In contrast, exercise produces large reductions in pain and disability, a feature that suggests that exercise should play a major role in the management of chronic LBP. Physical treatments, such as acupuncture, backschool, hydrotherapy, lumbar supports, magnets, TENS, traction, ultrasound, Pilates therapy, Feldenkrais therapy, Alexander technique, and craniosacral therapy are either of unknown value or ineffective and so should not be considered. Outside of primary care, multidisciplinary treatment or functional restoration is effective; however, the high cost probably means that these programs should be reserved for patients who do not respond to cheaper treatment options for chronic LBP. Although there are now effective treatment options for chronic LBP, it needs to be acknowledged that the problem of chronic LBP is far from solved. Though treatments can provide marked improvements in the patient's condition, the available evidence suggests that the typical chronic LBP patient is left with some residual pain and disability. Developing new, more powerful treatments and refining the current group of known effective treatments is the challenge for the future.

Acute low back pain: systematic review of its prognosis

OBJECTIVES

To describe the course of acute low back pain and sciatica and to identify clinically important prognostic factors for these conditions.

DESIGN

Systematic review.

DATA SOURCES

Searches of Medline, Embase, Cinahl, and Science Citation Index and iterative searches of bibliographies.

MAIN OUTCOME MEASURES

Pain, disability, and return to work.

RESULTS

15 studies of variable methodological quality were included. Rapid improvements in pain (mean reduction 58% of initial scores), disability (58%), and return to work (82% of those initially off work) occurred in one month. Further improvement was apparent until about three months. Thereafter levels for pain, disability, and return to work remained almost constant. 73% of patients had at least one recurrence within 12 months.

CONCLUSIONS

People with acute low back pain and associated disability usually improve rapidly within weeks. None the less, pain and disability are typically ongoing, and recurrences are common.

Contacting points overhead with and without a tennis racquet

Wielding an object or tool has been proposed to extend automatically the body's boundary to the tip of the held object. A sample of convenience consisted of 7 women and 5 men whose mean age was 23 yr. Using recreational tennis skills they judged the location of unseen overhead points of contact, where accuracy of discrimination was measured for movements to contact made with and without use of a tennis racquet. Points-of-contact overhead touched by the hand were significantly better discriminated after a backward and upward arm swing than when contact was made after a similar swing with a tennis racquet.

Systematic review of conservative interventions for subacute low back pain

OBJECTIVE

To evaluate the effect of conservative interventions on clinically relevant outcome measures for patients with subacute low back pain. This is particularly important because effective treatment for subacute low back pain will prevent the transition to chronic low back pain, a condition that is largely responsible for the high health care costs of low back pain.

DESIGN

Systematic review of randomized controlled trials.

MAIN OUTCOME MEASURES

Methodological quality of each trial was assessed. Effect sizes and 95% confidence intervals were calculated for pain and disability and risk ratios for return to work.

RESULTS

Thirteen trials were located, evaluating the following interventions: manipulation, back school, exercise, advice, transcutaneous electrical nerve stimulation (TENS), hydrotherapy, massage, corset, cognitive behavioural treatment and co-ordination of primary health care. Most studies were of low quality and did not show a statistically significant effect of intervention. For the strict duration of low back pain (six weeks to three months), no evidence of high internal validity was found but when other methodological criteria were considered, evidence was found for the efficacy of advice. Furthermore, there is evidence that when a broader view is taken of the duration of subacute low back pain (seven days to six months), other treatments (e.g. manipulation, exercise, TENS) may be effective.

CONCLUSIONS

Our review identified a major gap in the evidence for interventions that are currently recommended in clinical practice guidelines for the treatment of subacute low back pain. Lack of a uniform definition of subacute low back pain further limited current evidence.

Effect of applying different "levels of evidence" criteria on conclusions of Cochrane reviews of interventions for low back pain

The objective of this study was to examine the consistency of conclusions of Cochrane systematic reviews when different criteria are used to determine levels of evidence. We reanalyzed the data in six Cochrane reviews of conservative treatment of low back pain by applying three additional sets of "levels of evidence" criteria. Overall agreement between the conclusions attained with the different levels of evidence criteria was only "fair" (multirater kappa coefficient 0.33; 95% CI 0.28 to 0.38). For example, the four sets of levels of evidence criteria produced four conclusions on the efficacy of back school: "strong evidence that back schools are effective," "weak evidence," "limited evidence," and "no evidence." Pairwise agreement between the four pooling systems ranged from slight to substantial (kappas ranging from 0.10 to 0.80). Different rules for determining levels of evidence in systematic reviews produce markedly different conclusions on treatment efficacy. Crown

Randomized controlled trial of neural mobilization after spinal surgery

STUDY DESIGN

Randomized controlled trial with 12-month follow-up.

OBJECTIVES

To determine whether the addition of neural mobilization to standard postoperative care improved the outcome of lumbar spinal surgery.

SUMMARY OF BACKGROUND DATA

It has been suggested that neural mobilization should be performed after spinal surgery to prevent nerve root adhesions and improve outcome. However, to date, there is no convincing evidence of the value of neural mobilization.

METHODS

Eighty-one patients undergoing lumbar discectomy, fusion, or laminectomy at a private hospital in Sydney were randomly allocated to standard postoperative care or standard care plus neural mobilization. Neural mobilization included passive movements and active exercises designed to mobilize the lumbosacral nerve roots and sciatic tract. Primary outcome measures were global perceived effect measured on a 7-point scale, pain measured using visual analogue scales and the McGill Pain Questionnaire, and disability measured with the Quebec Disability Scale.

RESULTS

All patients received the treatment as allocated with 12-month follow-up data available for 76 patients (94% of those randomized). There were no statistically significant or clinically significant benefits provided by the neural mobilization treatment for any outcome.

CONCLUSIONS

The neural mobilization protocol evaluated in this study did not provide an additional benefit to standard postoperative care for patients undergoing spinal surgery. The authors advocate that this protocol not be used in clinical practice.

Development of an instrumented couch to measure forces during manual physiotherapy treatment

This paper reports on an instrumented couch developed to measure the forces applied during posteroanterior (PA) mobilization to the lumbar spine. The couch was evaluated for reliability by applying known weights to the empty couch, while accuracy was investigated by applying weights both to the empty couch and to a human subject lying on the couch. The equipment appears highly reliable when measuring forces in three directions (ICC(2,1); 99% CI=0.99-1.00) and also demonstrates acceptable accuracy; a maximum error of less than 2% being obtained when measuring forces applied to human subjects. The results demonstrate a highly linear relationship (r2=0.99) between the force readings and the known weights. In conclusion, the instrumented couch demonstrates suitable accuracy and reliability for measuring the force applied to a subject during the application of PA mobilization to the lumbar spine.

Indenter head area and testing frequency effects on posteroanterior lumbar stiffness and subjects' rated comfort

Although several mechanical devices have been developed to objectively assess posteroanterior (PA) stiffness of the lumbar spine, no standardized testing protocol has been adopted. Two factors that may vary across protocols, and that effect measured stiffness and the comfort of the test subject, are the size of the indenter head used to apply the PA pressure, and indenting frequency. Three variables; PA stiffness, defined as the slope of the stiffness curve (K), the displacement of the indenter at 30N (D30), and rating of perceived comfort, were measured in 36 subjects asymptomatic for low back pain. For each subject nine tests were conducted, using three different indenter head sizes (300mm(2), 720mm(2)and 1564mm(2)) at each of three different testing frequencies (0.25 Hz, 0.5 Hz and 2 Hz). Machine testing with a large indenter head produced a lower K value, an increased D30 value and higher perceived comfort, while a fast testing frequency produced a higher K value and a lower D30 value. An indenter size by frequency interaction showed small indenter heads to be least comfortable at slow speed. The differences found suggest that the indenter head size and the testing frequency should be standardized during mechanical spinal stiffness testing.

PEDro. A database of randomized trials and systematic reviews in physiotherapy

This paper describes PEDro, the Physiotherapy Evidence Database. PEDro is a web-based database of randomized controlled trials and systematic reviews in physiotherapy. It can be accessed free of charge at http://ptwww.cchs.usyd.edu.au/pedro. The database contains bibliographic details and abstracts of most English-language randomized trials and systematic reviews in physiotherapy, and of many trials and reviews in other languages. Trials on the database are rated on the basis of their methodological quality so that users of the database can quickly identify trials of high quality. Trials and systematic reviews are extensively indexed to facilitate searching. PEDro provides an important information resource to support evidence-based clinical practice.

The reliability and validity of the Biering-Sorensen test in asymptomatic subjects and subjects reporting current or previous nonspecific low back pain

STUDY DESIGN

A reliability study and case-control study were conducted.

OBJECTIVES

To determine the reliability and discriminative validity of the Biering-Sorensen test.

SUMMARY OF BACKGROUND DATA

A low Biering-Sorensen score has been found to predict who will have nonspecific low back pain. However, the reliability of the test remains controversial, implying that some studies may have produced results that underestimated the magnitude of the predictive validity of this test.

METHODS

Two raters measured the time holding a specific position (holding time) of 63 subjects (23 currently experiencing nonspecific low back pain, 20 who had had an episode, and 20 who were asymptomatic) while they performed the Biering-Sorensen test twice, 15 minutes apart. A standardized protocol was followed. Test-retest reliability was evaluated by calculating intra-class correlation coefficients (ICC 1,1), 95% confidence intervals (CI), and standard errors of the measurement (SEM) for the total group and for the subgroups. A three-way analysis of variance was used to determine whether test order, subject gender, or symptom status affected holding time.

RESULTS

High reliability indices were obtained for the Biering-Sorensen test in subjects with current nonspecific low back pain (ICC [1,1], 0.88; 95% CI, 0.73-0.95; SEM, 11.6 seconds), in subjects who had had nonspecific low back pain (ICC [1,1], 0.77; 95% CI, 0.52-0.90; SEM, 17.5 seconds), and in asymptomatic subjects (ICC [1,1], 0.83; 95% CI, 0.62-0.93; SEM, 17.4 seconds). Results of an analysis of variance showed that subjects asymptomatic for low back pain had a significantly longer holding time than the other two groups (P < 0.05).

CONCLUSIONS

The Biering-Sorensen test provides reliable measures of position-holding time and can discriminate between subjects with and without nonspecific low back pain.

Plinth padding confounds measures of posteroanterior spinal stiffness

This study investigated whether the presence of plinth padding influences measured posteroanterior spinal stiffness. Two measures of posteroanterior stiffness, the slope of the loading curve (K) and the displacement at 30 N (D30) were made at three vertebral levels: L3, T12 and T6, on a rigid and a padded plinth in 24 asymptomatic subjects. Analysis of variance demonstrated a significant reduction in K and increase in D30 when measured on the padded compared to the rigid surface and an interaction effect for both the K and D30 measures, indicating that the effect of the padding depends upon the vertebral level tested. The correlations between the padded and unpadded stiffness measures ranged from 0.70 to 0.87. The data from this study suggest that the type of plinth surface needs to be standardised when evaluating PA stiffness.

Number of sampling movements and manual stiffness judgments

OBJECTIVE

It has been suggested that when using posteroanterior pressure to assess the stiffness of the spine, no more than two or three oscillations should be used. This study sought to examine this clinical impression by investigating the effect of the number of sampling movements on stiffness perception.

DESIGN

Perceptual study using a mechanical device to provide stiffness stimuli, with university staff and students as judges.

SETTING

University psychophysics laboratory.

INTERVENTIONS

In part 1, subjects were directed to sample the stimuli a prescribed number of times (either 1, 2, 3, 4 or 5 pushes), whereas in part 2, subjects were free to choose the number of sampling movements.

MAIN OUTCOME MEASURE

Measures of interstimulus discriminability and bias.

RESULTS

An inverted-U relationship between the number of directed sampling movements and stiffness discriminability was found, with three cycles providing best discriminability. When subjects were given a choice, most chose to use three cycles. The number of sampling movements had no effect on bias.

CONCLUSION

This study confirms the hypothesis under investigation and suggests that therapists will be maximally sensitive when using three testing cycles of posteroanterior pressure to assess stiffness.

An investigation of the reliability and validity of posteroanterior spinal stiffness judgments made using a reference-based protocol

BACKGROUND AND PURPOSE

The reliability and criterion-related validity of ratings of posteroanterior (PA) spinal stiffness made using reference values for comparison have not been investigated. In this study, mechanical reference stimuli for points on an 11-point rating scale were used to determine whether using a reference scale may be feasible. Subjects. Five different raters took part in 2 studies in which they rated 40 subjects who were asymptomatic for low back pain.

METHODS

The interrater reliability of ratings was evaluated with intraclass correlation coefficients (ICCs) and standard errors of the measurement (SEMs). Criterion-related validity was evaluated by correlating judgments of PA spinal stiffness assessed manually with measurements of PA spinal stiffness provided by a mechanical device, the "Stiffness Assessment Machine" (SAM).

RESULTS

Although the reliability indices were generally high, with ICCs reaching .77 and with SEMs as low as 0.72 points, the evidence for criterion-related validity (i.e., the ability of the examiner to judge spinal stiffness levels) was not strong, with correlations reaching only .56.

CONCLUSIONS AND DISCUSSION

The reference-based protocol allows for more reliable measures of PA stiffness judgments than previous protocols have; however, the human ratings are not highly correlated with the SAM measures. The protocol will have clinical value if judgments made using it are shown to be reliable in clinically relevant subjects and to have validity for clinical management of patients.