Natural course of acute neck and low back pain in the general population: The HUNT study

In this prospective cohort study we aimed to describe the natural course of acute neck and low back pain in a general population of Norway. We screened 9056 subjects aged 20–67 years who participated in a general health survey for a new episode of neck or low back pain the previous month. The screening identified 219 subjects who formed the cohort for this study. Pain intensity was reported on a numeric rating scale (0–10) at 1, 2, 3, 6, and 12 months after start of the new pain episode. The course of pain was described for neck and low back pain, different baseline pain levels, age groups, and number of pain sites at baseline. Use of medication and health care was described and associations between pain intensity and seeking health care were estimated. Pain declined rapidly within 1 month after a new pain episode, with a reduction of 0.91 (95% confidence interval [CI] 0.50–1.32) for neck pain and 1.40 (95% CI 0.82–1.99) for low back pain with little change thereafter. However, pain remained unchanged over the follow-up year for those with equal pain in the neck and low back areas at baseline and for those reporting 4 or more pain sites at baseline. Only 1 in 5 sought health care for their complaints. Still, the course of pain was comparable to effect sizes reported in interventional studies. This study thus contributes natural course reference data for comparisons of pain outcome in clinical trials and practice.     

Prevalence of chronic pain with neuropathic characteristics in the general population

We conducted a large nationwide postal survey to estimate the prevalence of chronic pain with or without neuropathic characteristics in the French general population. A questionnaire aimed at identifying chronic pain (defined as daily pain for at least 3 months), evaluating its intensity, duration and body locations, was sent to a representative sample of 30,155 subjects. The DN4 questionnaire was used to identify neuropathic characteristics. Of the questionnaires, 24,497 (81.2%) were returned and 23,712 (96.8%) could be assessed. Seven thousand five hundred and twenty-two respondents reported chronic pain (prevalence=31.7%; [95%CI: 31.1-32.3]) and 4709 said the pain intensity was moderate to severe (prevalence=19.9%; [95%CI: 19.5-20.4]). Neuropathic characteristics were reported by 1631 respondents with chronic pain (prevalence=6.9%; [95%CI: 6.6-7.2]), which was moderate to severe in 1209 (prevalence=5.1% [95%CI: 4.8-5.4]). A higher prevalence of chronic pain with neuropathic characteristics was associated with middle age (50-64 years), manual professions and those living in rural areas. It was more frequently located in the lower limbs and its intensity and duration were higher in comparison with chronic pain without neuropathic characteristics. This large national population-based study indicates that a significant proportion of chronic pain patients report neuropathic characteristics. We identified distinctive socio-demographic profile and clinical features indicating that chronic pain with neuropathic characteristics is a specific health problem.     

Incidence rates and treatment of neuropathic pain conditions in the general population

Incidence rate estimates of neuropathic pain are scanty and mostly address single types whereas the scope of the disease is wide. We aimed to calculate the incidence rates of neuropathic pain conditions in the Dutch general population and to assess treatment strategies in primary care. The study population included persons registered for at least one year in the Integrated Primary Care Information (IPCI) database between 1996 and 2003. Neuropathic pain was ascertained and classified by systematic review of computerized longitudinal medical records. Incidence rates (IR) were calculated, and the treatment for pain was compared to age and gender matched controls. Among 362,693 persons contributing 1,116,215 person years (PY), we identified 9135 new cases of neuropathic pain (IR: 8.2/1000 PY, 95%CI: 8.0–8.4). Mononeuropathy and carpal tunnel syndrome were the most frequent types with 4.3 and 2.3 cases/1000 PY followed by diabetic peripheral neuropathy and post-herpetic neuralgia at 0.72 and 0.42/1000 PY. Neuropathic pain was 63% more common in women than in men and peaked between the ages 70 and 79. More than 50% of cases received pain medication within 6 months after diagnosis, mostly consisting of NSAIDs or aspirin. Anticonvulsants and tricyclic antidepressants were only used by 4.8 and 4.7% of cases. Neuropathic pain is a rather frequent condition with an annual incidence of almost 1% of the general population and affecting women and middle-aged persons more often. The treatment mostly consisted of regular analgesics suggesting that pharmacological treatment of neuropathic pain is suboptimal.     

General practitioners' fear-avoidance beliefs influence their management of patients with low back pain

The objectives of this cross-sectional study conducted in primary care practice in France were to describe general practitioners' (GPs) fear-avoidance beliefs about low back pain (LBP), investigate the impact of these beliefs on their following guidelines for bed rest, physical activities, and sick leave, and uncover factors associated with GPs' fear-avoidance beliefs. A total of 864 GPs completed a 5-part self-administered questionnaire. Parts 1, 2, and 3 concerned demographic, professional data, and personal history of back pain, respectively. Part 4 dealt with GPs' education about LBP and practice for LBP. Part 5 assessed GPs' fear-avoidance beliefs on the Fear-Avoidance Beliefs Questionnaire (FABQ). GPs' mean age was 48.2+/-7.0 years, 80% were male, 88% had been practicing for more than 10 years, and 52% reported a previous personal episode of acute LBP. Forty-six percent had participated in an educational session on LBP during the last 3 years. Mean scores for the FABQ Phys and Work were 9.6+/-4.8 and 17.5+/-6.7, respectively. Sixteen percent of participants had high rating on the FABQ Phys (FABQ Phys score>14). FABQ Phys score was associated with recommendation of bed rest or rest during sick leave (p<0.0001) for acute LBP and less advice to maintain maximum bearable physical activities (p<0.001) for chronic LBP. FABQ Work score was associated with prescribing sick leave during painful periods (p<0.005) for acute LBP and less advice to maintain maximum bearable physical activities (p<0.001) for chronic LBP. GPs' fear-avoidance beliefs about LBP negatively influence their following guidelines concerning physical and occupational activities for patients with LBP.     

The relationship between pain,disability, quality of life and cognitive-behavioural factors in chronic back pain

Purpose: This pilot study systematically examined the correlations between the outcome variables pain intensity, disability and health-related quality of life (HRQOL) and between these outcomes and known psychological risk factors for chronic low back pain (CLBP), such as depression, trait anxiety, avoidance- and endurance-related pain responses at two different assessment points. Method: Data from 52 CLBP inpatients treated in an orthopedic clinic were investigated at two points in time: during the first days after admission and 6 months after the termination of the inpatient treatment. Bivariate relationships between pain intensity, disability, HRQOL and psychological variables were examined with the help of Pearson product moment correlations. Furthermore, the differences that exist between correlations at baseline and follow-up were tested for significance. Results: Significant and large differences were found between the correlations with low correlations at baseline and high correlations at the follow-up. Furthermore, HRQOL showed a positive correlation with endurance-related and a negative correlation with avoidance-related pain responses. Conclusions: Focusing on a systematic comparison of two significant assessment time points in CLBP with an acute exacerbation at baseline, the results of this study underlined the recurrent course of LBP. The results highlight that the assessment time points play an important role in CLBP.

Implications for Rehabilitation

• Low back pain is a major public health problem with high direct and indirect back-pain-related costs.

• Chronic low back pain is a disabling disease which restricts quality of life.

• Psychological factors may have a larger impact on disability and quality of life than pain itself.

• The recurrent course of low back pain highlights the importance of multidisciplinary pain management even during acute exacerbations of pain.

     

Do epidemiological results replicate? The prevalence and health‐economic consequences of neck and back pain in the general population

Current estimates of the prevalence and consequences of neck and back pain vary greatly between studies. It is not known whether this variance is due to differences in methodology, or if it depends on the dynamics of the problem over time. The aim of this study was consequently an attempt to replicate and extend the findings of a previous epidemiological study using the same methodology on a new population. A survey of 3000 35-45 year olds, selected at randon, was conducted to determine the prevalence, site, frequency and intensity of the pain as well as any work loss or health-care utilization. The response rate was 69% and an analysis of non-responders showed that they were very similar to responders, but had a slightly lower prevalence. The results replicated the original study: 73% reported back pain during the past year and the consequences included considerable suffering and functional impairment. Moreover, 17% of those reporting pain had utilized sick leave during the past year for the problem, while an additional 14% had been off work but had not used sick leave. Sufferers averaged 3.5 health-care visits during the past year. However, the consumption of resources was highly skewed and about 6% of the sufferers accounted for over 50% of the costs. It was concluded that when the same selection criteria and assessment techniques are employed, the results found are quite similar. This implies that much of the huge variation in reported prevalence rates and consequences of back pain may be due to methodological differences. This underscores the need for standardized methods.     

Spinal shrinkage and recovery in women with and without low back pain

OBJECTIVES: To assess the behavior of the spinal column after loading in participants with and without low back pain (LBP) using spinal shrinkage measurements as a criterion and to analyze the relations among spinal shrinkage, recovery, and LBP. DESIGN: A case-control study with repeated measures. SETTING: University department with recruitment from primary care. PARTICIPANTS: Convenience sample of 31 women (15 with chronic, nondisabling LBP [LBP group]; 16 with no history of low back disorders [control group]). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Changes in body length as determined by using a stadiometer. RESULTS: The spinal shrinkage induced by the exercise was similar ( P >.05) in both groups (control group, mean +/- standard deviation of -3.99+/-1.13 mm; LBP group, -4.16+/-1.54 mm). Differences in spinal length were found after 20 minutes in the recovery position ( P <.05). The control group was able to recover stature to a greater extent (111.2%+/-13.6%) than the LBP group ( P <.05), which was unable to regain stature beyond baseline (57.5%+/-25.1%). A negative correlation was found between regaining stature and low back pain ( r =-.52, P <.05). CONCLUSIONS: Participants with LBP were unable to recover stature to the same extent as controls. We suggest that LBP is related to the diminished ability to recover rather than to the magnitude of the spinal shrinkage imposed during the task.     

Learning processes in the persistence behavior of chronic low back pain patients with repeated acute pain stimulation

Twenty-one chronic low back pain (CLBP) patients and 20 control subjects participated in 8 successive cold pressor tests (CPT). The hypotheses were that: (1) CLBP patients would demonstrate poorer acute pain tolerance and report higher acute pain, and (2) CLBP patients would become sensitized during 8 successive CPT trials, while control subjects would habituate, resulting in increasing differences in test behavior between both groups.

The results show that the first hypothesis was confirmed. The second hypothesis requires modification, as the control group both habituated and became sensitized, while within the CLBP group no learning or training effect was found. These findings lead one to conclude that the deviant acute pain behavior of CLBP patient may be regarded either as a consequence of CLBP or as an important risk factor in the development of CLBP.

Patients with relatively high CLBP levels performed poorly on the CPT as compared with patients with relatively low CLBP levels.     

General practitioners’ treatment orientations towards low back pain: Influence on treatment behaviour and patient outcome

Background: In low back pain (LBP) treatment and research attention has shifted from a biomedical towards a biopsychosocial approach. Patients’ LBP beliefs and attitudes were found to predict long‐term outcome, and recently it has been suggested that the health care providers’ ideas about LBP are also important predictors of treatment behaviour and outcome. Aims: In the present study we examined whether (1) differences in General Practitioners’ (GP) LBP treatment orientation are associated with differences in actual treatment behaviour and (2) whether treatment orientation is related to LBP outcome in patients. Methods: Two hundred twenty two patients consulting their GP with a new episode of LBP were recruited and completed questionnaires on (among others) LBP outcome (graded chronic pain scale) at baseline, during 12 months of follow‐up and at the end of the study. Data on treatment were collected from the GPs. The GPs also completed a set of questionnaires on LBP treatment orientation. Associations between measures of treatment orientation, treatment recommendations, treatment behaviour and LBP outcome were analysed. Results: A biomedical treatment orientation was found to be associated with more concern about tissue damage and the effect of physical activity on pain and recovery in vignettes. No associations were found between treatment orientation measures, actual treatment behaviour and LBP outcome. Conclusions: Associations were not found as expected. Still these findings are relevant and may feed a clinically important debate on widely accepted assumptions about the role and influence of health care providers in changing patients’ pain behaviours.     

The course of chronic and recurrent low back pain in the general population

Using latent class analysis (LCA), a previous study on patients attending primary care identified four courses of low back pain (LBP) over the subsequent 6 months. To date, no studies have used longitudinal pain recordings to examine the “natural” course of recurrent and chronic LBP in a population-based sample of individuals. This study examines the course of LBP in the general population and elaborates on the stability and criterion-related validity of the clusters derived. A random sample of 400 individuals reporting LBP in a population-based study was asked to complete a comprehensive questionnaire at the start and end of the year’s survey, and 52 weekly pain diaries in between. The latter were analyzed using LCA. 305 individuals returned more than 50% of the diaries. Four clusters were identified (severe persistent, moderate persistent, mild persistent, and fluctuating). The clusters differed significantly with regards to pain and disability. Assessment of cluster stability showed that a considerable proportion of patients in the “fluctuating” group changed their classification over time. Three of the four clusters describing the typical course of pain matched the clusters described previously for patients in primary care. Due to the population-based design, this study achieves, for the first time, a close insight into the “natural” course of chronic and recurrent low back pain, including individuals that did not necessarily visit the general practitioner. The findings will help to understand better the nature of this pain in the general population.     

Analyzing chronic low back pain: the relative contribution of pain coping strategies

Sixty-two chronic low back pain patients were administered the Coping Strategies Questionnaire (CSQ) to assess the frequency of use and perceived effectiveness of a variety of cognitive and behavioral pain coping strategies. Analysis of individual variables revealed that CSQ factors, gender, physical examination findings, and chronicity of pain had significant effects on one or more of a series of pain, psychological distress or behavioral measures. To assess the relative contribution of each of these variables hierarchical stepwise regression analyses were carried out. These analyses revealed that the Helplessness factor of the CSQ explained 50% of the variance in psychological distress (Global Severity Index of the SCL-90R), and 46% of the variance in depression (Beck Depression Inventory). Patients scoring high on this CSQ factor had significantly higher levels of psychological distress. None of the demographic or medical status variables explained a significant proportion of variance in the psychological distress measures. The Diverting Attention and Praying factor of the CSQ explained a moderate (9%), but significant amount of variance in pain report. Patients scoring high on this factor had higher scores on the McGill Pain Questionnaire. Coping strategies were not strongly related to pain behavior measures such as guarding or uptime. A consideration of pain coping strategies may allow one to design pain coping skills training interventions so as to fit the needs of the individual low back pain patient.     

Reduced task-induced variations in the distribution of activity across back muscle regions in individuals with low back pain

This study investigated change in the distribution of lumbar erector spinae muscle activity and pressure pain sensitivity across the low back in individuals with low back pain (LBP) and healthy controls. Surface electromyographic (EMG) signals were recorded from multiple locations over the lumbar erector spinae muscle with a 13 × 5 grid of electrodes from 19 people with chronic nonspecific LBP and 17 control subjects as they performed a repetitive lifting task. The EMG root mean square (RMS) was computed for each location of the grid to form a map of the EMG amplitude distribution. Pressure pain thresholds (PPT) were recorded before and after the lifting task over a similar area of the back. For the control subjects, the EMG RMS progressively increased more in the caudal region of the lumbar erector spinae during the repetitive task, resulting in a shift in the distribution of muscle activity. In contrast, the distribution of muscle activity remained unaltered in the LBP group despite an overall increase in EMG amplitude. PPT was lower in the LBP group after completion of the repetitive task compared to baseline (average across all locations: pre: 268.0 ± 165.9 kPa; post: 242.0 ± 166.7 kPa), whereas no change in PPT over time was observed for the control group (320.1 ± 162.1 kPa; post: 322.0 ± 179.5 kPa). The results demonstrate that LBP alters the normal adaptation of lumbar erector spinae muscle activity to exercise, which occurs in the presence of exercise-induced hyperalgesia. Reduced variability of muscle activity may have important implications for the provocation and recurrence of LBP due to repetitive tasks.     

A national framework for supporting improvements in the physiotherapy assessment and management of low back pain: the Scottish experience

Background

Similar to other countries worldwide, Scotland lacked a national view of whether the quality of the physiotherapy management of low back pain was compliant with national guidelines. Anecdotal evidence suggested that standards of care varied considerably despite the wide availability of clinical guidelines to clinicians.

Aim

To develop a framework that supports National Health Service (NHS) Scotland in providing consistently applied high-quality physiotherapy assessment and management of low back pain in line with guideline recommendations.

Design

Prospective, multicentred national study, data collection and improvement phase.

Setting

All NHS boards in Scotland (n = 14) plus two private provider sites.

Participants

One hundred and eighty-six individual NHS sites and two private providers of services to patients with low back pain.

Method

A national dataset was developed from evidence- and consensus-based guideline sources. All sites collected data (two 5-week periods) over 1 year (2008-2009) using a web-based database. This was interspersed by an improvement phase during which required improvements were considered and implemented. Issues were shared through a national network and national meeting.

Results

Data from 2147 patients showed improvements in the documented physiotherapy management of low back pain over the two cycles. All participants developed and implemented remedial action plans based on the results of the first cycle.

Conclusion

It is possible to implement a framework, which is led nationally but driven and owned locally, supporting physiotherapists in an active programme of locally determined improvement. However, although process and outcome are linked, the direct impact of this initiative on patient outcome is not known.     

Superficial temperature and pain tolerance in patients with chronic low back pain

IntroductionLow back pain is a common and very prevalent disease and can impose limitations that negatively impact patients. The objective of this study was to verify and compare the association between lumbar superficial temperature and pressure pain tolerance thresholds in individuals with chronic nonspecific low back pain and healthy controls.MethodsThis was a cross-sectional observational study involving 38 individuals with nonspecific chronic low back pain and 19 healthy controls. Volunteers underwent thermographic (infrared sensor), pain perception (visual analog scale), and pressure pain tolerance thresholds (algometry) evaluations in the right and left paravertebral muscles and L4-L5 ligament.ResultsA lower tolerance to pressure pain was found in patients compared to controls at all evaluated sites (p ≤ 0.003). Superficial temperature was significantly higher in the sites evaluated in the low back pain group (p < 0.001). In patients with low back pain, pain perception was weakly and inversely correlated with pressure pain tolerance (r = -0.31; p = 0.05) and moderately correlated to the temperature of the evaluated sites (r = 0.51 to 0.59, p ≤ 0.001). Also, an inverse and weak to moderate association was observed between pressure pain tolerance thresholds and temperature in patients only (r = -0.36 to −0.49; p ≤ 0.02).ConclusionIndividuals with low back pain have lower pressure pain tolerance thresholds and higher superficial temperature in the lumbar region when compared to healthy individuals. The associations observed show that the higher the pain perception, the lower the pain tolerance and the higher the superficial temperature in the lumbar region. Also, the higher the temperature, the lower the pain tolerance.     

Isolated lumbar extensor strengthening versus regular physical therapy in an army working population with nonacute low back pain: a randomized controlled trial

Helmhout PH, Harts CC, Viechtbauer W, Staal JB, de Bie RA. Isolated lumbar extensor strengthening versus regular physical therapy in an army working population with nonacute low back pain: a randomized controlled trial.

Objective

To evaluate the effectiveness of specific lumbar extensor training compared with regular physical therapy (PT) in workers with nonspecific nonacute low back pain (LBP).

Design

A multicenter randomized controlled trial with 1-year follow-up.

Setting

PT department in (military primary care) health centers.

Participants

Predominantly male soldiers (N=129) with 4 weeks or more of low back complaints who were referred by the health center's general practitioner for PT (mean age, 35.9±10.8y; range, 20-56y), of whom 127 randomized participants were included in the analyses. One patient withdrew because of adverse effects during treatment.

Interventions

Participants were assigned to 1 of 2 treatment programs: (1) a 10-week device-supported isolated lumbar extension training, twice a week, or (2) regular PT, mainly consisting of exercise therapy and aerobic activities.

Main Outcome Measures

Functional status (Roland-Morris Disability Questionnaire, Patient-Specific Functional Scale) and global perceived effect were assessed in the short term (5wk, 10wk) and long term (6mo, 12mo).

Results

Both groups showed a favorable development in main outcomes over time: short-term improvements (after 10 weeks of treatment) remained stable or even slightly increased throughout the 12-month follow-up. No significant differences between the 2 groups were shown for any of the outcome measures, at any time.

Conclusions

Consistent with prior evidence, specific back strengthening does not seem to offer incremental benefits in LBP management compared with regular PT care that mainly consists of general exercise therapy. (ISRCTN identifier ISRCTN19334317.)