Effects of intervention program for systematic use of transfer equipment on care workers' low back pain in elderly care facilities

OBJECTIVE

The purpose of this study was to investigate the effects of an intervention program to prevent care workers' low back pain by the systematic use of transfer equipment at elderly care facilities.

METHODS

Questionnaire surveys were administered to administrators and care workers before (baseline), 1 year after, and 2.5 year after starting the program at two elderly care facilities. Care workers at the intervention facility were requested to ensure the use of a transfer's hoist, sliding board, and sliding sheet when assisting in the transfer of residents who were judged as appropriate to use the equipment (27.5% of residents living the intervention facility). Care workers at the control facility received no instructions on the use of transfer equipment.

RESULTS

The average response rate of administrators and care workers was 100% and 90.3%, respectively. The number of care workers who responded during all three survey periods was 29 at the intervention facility and 23 at the control facility, and they were subjected to the current analysis. At baseline, transfer equipment was already introduced in both facilities, but it was found that the care workers did not regularly use it for assisting transfer. At 2.5-year follow-up, 31.0% of the intervention group and 4.3% of the control group always used the transfer's hoist. Similarly, 27.6% of the intervention group and 4.3% of the control group always used the sliding board and sliding sheet. Further, 60%-70% of the care workers at both facilities reported of having low back pain, but no statistically significant difference was found between the facilities or over the measurement periods. Among the intervention group, however, the care workers who reported an active use of the transfer's hoist, sliding board, and sliding sheet showed an improvement in low back pain. In the control group, no significant association was found between the active use of transfer equipment and low back pain.

CONCLUSION

These results indicated that the prevention of care workers' low back pain requires the introduction of transfer equipment in facilities and its regular use under the implementation program. If the number of residents requiring transfer equipment increases, its systematic use is expected to improve low back pain in care workers. This improvement can translate into safer and healthier workplaces for elderly care.

Prognostic psychosocial factors for disabling low back pain in Japanese hospital workers

Background

Although the occupational health field has identified psychosocial factors as risk factors for low back pain that causes disability, the association between disabling low back pain and psychosocial factors has not been examined adequately in Japanese hospital workers. Therefore, this study examined the association between low back pain, which interfered with work, and psychosocial factors in Japanese hospital workers.

Method

This cross-sectional study was conducted at a hospital in Japan. In total, 280 hospital workers were recruited from various occupational settings. Of these, 203 completed a self-administered questionnaire that included items concerning individual characteristics, severity of low back pain, fear-avoidance beliefs (Fear-Avoidance Beliefs Questionnaire), somatic symptoms (Somatic Symptom Scale-8), psychological distress (K6), workaholism, and work-related psychosocial factors (response rate: 72.5%). Logistic regression was used to explore risk factors associated with disabling low back pain.

Results

Of the 203 participants who completed questionnaires, 36 (17.7%) reported low back pain that interfered with their work. Multivariate analyses with individual factors and occupations adjusted for showed statistically significant associations between disabling low back pain and fear-avoidance beliefs (adjusted odds ratio [OR]: 2.619, 95% confidence interval [CI]: 1.003–6.538], somatic symptoms (OR: 4.034, 95% CI: 1.819–9.337), and interpersonal stress at work (OR: 2.619, 95% CI: 1.067–6.224).

Conclusions

Psychosocial factors, such as fear-avoidance beliefs, somatic symptoms, and interpersonal relationships at work, were important risk factors in low back pain that interfered with work in Japanese hospital workers. With respect to occupational health, consideration of psychosocial factors is required to reduce disability related to low back pain.

Epidemiological Differences Between Localized and Nonlocalized Low Back Pain

STUDY DESIGN

A cross-sectional survey with a longitudinal follow-up.

OBJECTIVES

The aim of this study was to test the hypothesis that pain, which is localized to the low back, differs epidemiologically from that which occurs simultaneously or close in time to pain at other anatomical sites SUMMARY OF BACKGROUND DATA.: Low back pain (LBP) often occurs in combination with other regional pain, with which it shares similar psychological and psychosocial risk factors. However, few previous epidemiological studies of LBP have distinguished pain that is confined to the low back from that which occurs as part of a wider distribution of pain.

METHODS

We analyzed data from CUPID, a cohort study that used baseline and follow-up questionnaires to collect information about musculoskeletal pain, associated disability, and potential risk factors, in 47 occupational groups (office workers, nurses, and others) from 18 countries.

RESULTS

Among 12,197 subjects at baseline, 609 (4.9%) reported localized LBP in the past month, and 3820 (31.3%) nonlocalized LBP. Nonlocalized LBP was more frequently associated with sciatica in the past month (48.1% vs. 30.0% of cases), occurred on more days in the past month and past year, was more often disabling for everyday activities (64.1% vs. 47.3% of cases), and had more frequently led to medical consultation and sickness absence from work. It was also more often persistent when participants were followed up after a mean of 14 months (65.6% vs. 54.1% of cases). In adjusted Poisson regression analyses, nonlocalized LBP was differentially associated with risk factors, particularly female sex, older age, and somatizing tendency. There were also marked differences in the relative prevalence of localized and nonlocalized LBP by occupational group.

CONCLUSION

Future epidemiological studies should distinguish where possible between pain that is limited to the low back and LBP that occurs in association with pain at other anatomical locations.

LEVEL OF EVIDENCE

2.

Prognostic factors associated with the surgical indication for lumbar spinal stenosis patients less responsive to conservative treatments: An investigator-initiated observational cohort study

BACKGROUND

A few cohort studies have determined which patients with lumbar spinal stenosis are likely to need surgery because of the deterioration of symptoms. However, there are still insufficient data regarding the management of lumbar spinal stenosis due to lack of prognostic factors associated with the need for surgery. The purpose of this study was to identify the prognostic factors associated with the need for surgical treatment in patients with lumbar spinal stenosis.

METHODS

Patients with lumbar spinal stenosis from our hospital and related facilities were enrolled. Eligibility criteria were as follows: age 50-85 years and the patient's conditions met the definition of lumbar spinal stenosis; the presence of neurogenic intermittent claudication caused by numbness and/or pain in the lower limbs; and magnetic resonance imaging-confirmed symptomatic LSS. We followed 274 patients (151 men; mean age, 71 ± 7.4 years) for 3 years to identify prognostic factors. We used a multivariate logistic regression model to investigate the association between the indication for surgical treatment (within 3 years) and age, sex, complications, depression, illness duration, the presence of cauda equina symptoms, and the presence of degenerative spondylolisthesis/scoliosis.

RESULTS

In the survey conducted 3 years after treatment, 185 patients responded (follow-up rate 67.5%). In 82 patients, surgery was performed during the follow-up period. The multivariate logistic regression model showed that the presence of cauda equina symptoms and the presence of degenerative spondylolisthesis/scoliosis were significantly associated with the indication for surgical treatment within 3 years.

CONCLUSIONS

This study showed that the presence of cauda equina symptoms and degenerative spondylolisthesis/scoliosis were prognostic factors associated with the indication for surgery in patients with lumbar spinal stenosis.

Development of a Japanese version of the Somatic Symptom Scale-8: Psychometric validity and internal consistency

OBJECTIVE

We aimed to psychometrically validate the Japanese version of the Somatic Symptom Scale-8 (SSS-8) in Japanese individuals.

METHOD

Data were collected from Japanese individuals aged 20-64years, who were recruited online, in February 2015. The scale reliability and validity were analyzed.

RESULTS

Data from 52,353 individuals were analyzed. Cronbach's alpha for the assessment of internal consistency reliability was 0.86 for the total score. The concurrent validity results showed strong correlations with three domains of the Profile of Mood States-Brief form (ρ=0.51-0.61) and the EuroQol 5 Dimension (ρ=-0.54). The known-group validity results indicated a linear trend in the severity of depression stratified using the Patient Health Questionnaire-2 (Jonckheere-Terpstra test, p<0.001). Regarding convergent and discriminant validities, all items correlated most strongly with their own domains (coefficients≥0.5), except for one item (headaches). Scores on perceived stress, pain, and general health differed across five SSS-8 severity groups (Steel-Dwass test, p<0.001), expect for one group pair in health.

CONCLUSION

The Japanese version of the SSS-8 was valid with good internal consistency. This questionnaire could help detect somatic symptom burdens of chronic and severe musculoskeletal pain for primary prevention.

Estimated risk for chronic pain determined using the generic STarT Back 5-item screening tool

Objective

The generic STarT Back 5-item screening tool (STarT-G) is used to manage chronic pain in the lower back and elsewhere. This study evaluated the validity of the Japanese version of this generic screening tool.

Materials and methods

Japanese participants between the ages of 20 and 64 years completed online surveys regarding pain. Survey reliability was assessed with internal consistency, as calculated using Cronbach’s alpha coefficients. Spearman’s correlation coefficients were used to evaluate concurrent validity between the STarT-G score and standard reference questionnaires. Associations between STarT-G scores and the presence of a disability due to chronic pain (DCP) were analyzed using receiver operator characteristic (ROC) curves.

Results

Analyses ultimately included data obtained from 52,842 Japanese participants (54.4% male) with a mean (standard deviation) age of 47.7 (9.4) years. Approximately 1.5% of participants had DCP, and the mean STarT-G score was 1.2 (1.4). The Cronbach’s alpha coefficient was 0.71, indicating an acceptable reliability. The STarT-G score moderately correlated with the pain numerical rating scale (NRS) score (Spearman’s correlation coefficient: r = 0.34). When the STarT-G threshold was set at 4, the sensitivity and specificity of the DCP predictive model were 65.8% and 82.4%, respectively, and the area under the ROC was 0.808.

Conclusion

The STarT-G was internally consistent and was able to distinguish between subjects with and without a DCP. Therefore, the STarT-G can reliably be used in the Japanese population to identify patients with DCP.

Sex-specific impact of early-life adversity on chronic pain: a large population-based study in Japan

BACKGROUND

Responses to early-life adversity may differ by sex. We investigated the sex-specific impact of early-life adversity on chronic pain, chronic multisite pain, and somatizing tendency with chronic pain.

METHODS

We examined 4229 respondents aged 20-79 years who participated in the Pain Associated Cross-Sectional Epidemiological Survey in Japan. Outcomes were: 1) chronic pain prevalence, 2) multisite pain (≥3 sites) prevalence, and 3) multiple somatic symptoms (≥3 symptoms) among respondents with chronic pain related to the presence or absence of early-life adversity. Multivariable-adjusted odds ratios (ORs) were calculated with 95% confidence intervals using a logistic regression model including age, smoking status, exercise routine, sleep time, body mass index, household expenditure, and the full distribution of scores on the Mental Health Inventory-5. We further adjusted for pain intensity when we analyzed the data for respondents with chronic pain.

RESULTS

The prevalence of chronic pain was higher among respondents reporting the presence of early-life adversity compared with those reporting its absence, with multivariable ORs of 1.62 (1.22-2.15, p<0.01) in men and 1.47 (1.13-1.90, p<0.01) in women. Among women with chronic pain, early-life adversity was associated with multisite pain and multiple somatic symptoms; multivariable ORs were 1.78 (1.22-2.60, p<0.01) for multisite pain and 1.89 (1.27-2.83, p<0.01) for ≥3 somatic symptoms. No associations were observed between early-life adversity and chronic multisite pain or multiple somatic symptoms among men with chronic pain.

CONCLUSION

Early-life adversity may be linked to a higher prevalence of chronic pain among both sexes and to multisite pain and somatizing tendency among women with chronic pain.

Fear-avoidance beliefs are independently associated with the prevalence of chronic pain in Japanese workers

PURPOSE

Pain is a global public health problem with implications for both personal and social heath. Fear-avoidance beliefs (FABs) have been demonstrated to negatively impact and prolong pain in many Western countries, but little is known about the association between FABs and chronic pain (CP) in Asian countries, including Japan. We examined the relationship between FABs and CP in Japanese white-collar workers, a growing population with a high prevalence of CP.

METHODS

Questionnaires and company records were used to gather data from 433 Japanese white-collar workers. Data were related to experience of pain, participant sociodemographic/health/lifestyle characteristics, fear-avoidance beliefs [Tampa Scale for Kinesiophobia (TSK)], work-related psychosocial factors (Brief Job Stress Questionnaire), and depressive illness [Psychological Distress Scale (K6)]. Analysis of covariance and multilevel logistic regression modeling were used to analyze associations between the data while controlling for factors known to influence CP prevalence.

RESULTS

Prevalence rate of CP was 11.1% (48 of 433 persons). Adjusted odds ratios for participants with CP significantly increased in participants with high TSK scores, even after adjusting for factors known to influence CP prevalence.

CONCLUSION

We found a significant association between high TSK scores and CP in Japanese white-collar workers when controlling for other known factors that influence CP such as work-related psychosocial characteristics and depressive conditions. This finding suggests that FABs are independently associated with prevalence of CP.

The relationship between findings on magnetic resonance imaging and previous history of low back pain

The objective of this study was to evaluate the relationship between magnetic resonance imaging (MRI) findings and previous low back pain (LBP) in participants without current LBP. Current LBP was defined as LBP during the past month. Previous LBP was defined as a history of medical consultation for LBP. Ninety-one participants without current LBP were included. Sagittal T2-weighted MRI was used to assess the intervertebral space from T12/L1 to L5/S1. These images were classified into five grades based on the Pfirrmann grading system. Furthermore, we evaluated the presence of disk bulging, high-intensity zone, and spondylolisthesis. We compared the MRI findings between groups with (27 participants) and without (64 participants) previous LBP without current LBP. Intraobserver and interobserver kappa values were evaluated. Participants had an average age of 34.9 years; 47 were female and 44 were male; and their average body mass index was 21.8 kg/m². Compared to the group of participants without previous LBP, the group of participants with previous LBP had a significantly higher incidence of disk degeneration such as a Pfirrmann grade ≥3, disk bulging, and high-intensity zone in the analyses adjusted by age and sex. There were no significant differences in spondylolisthesis between the groups. An odds ratio of >10 was only found for Pfirrmann grade ≥3, ie, a Pfirrmann grade ≥3 was strongly associated with a history of previous LBP in participants without current LBP.

Development of the Japanese Version of the Leeds Assessment of the Neuropathic Symptoms and Signs Pain Scale: Diagnostic Utility in a Clinical Setting

OBJECTIVE

We aimed to assess the diagnostic utility of the linguistically validated Japanese version of the Leeds Assessment of Neuropathic Symptoms and Signs Pain Scale (LANSS-J) as a screening tool for neuropathic pain in the clinical setting.

METHODS

Patients with neuropathic pain or nociceptive pain who were 20 to 85 years of age were included. Sensitivity and specificity using the original cutoff value of 12 were assessed to evaluate the diagnostic utility of the LANSS-J. Sensitivity and specificity with possible cutoff values were calculated, along with area under the receiver operating characteristic curve. We then evaluated agreement regarding assessment of the LANSS-J by two investigators. We used the intraclass correlation coefficient (ICC) for the total score and Cohen's kappa coefficient for each item.

RESULTS

Data for patients with neuropathic pain (n = 30) and those with nociceptive pain (n = 29) were analyzed. With a cutoff of 12, the sensitivity was 63.3% (19/30) and the specificity 93.1% (27/29). Sensitivity improved substantially with a cutoff of ≤ 11 (≥ 83.3%, 25/30). High specificity (93.1%, 27/29) was sustained with a cutoff of 9 to 12. The ICC for the total score was 0.85, indicating sufficient agreement. Kappa coefficients ranged from 0.68 to 0.84.

CONCLUSIONS

The LANSS-J is a valid screening tool for detecting neuropathic pain. Our results suggest that employing the original cutoff value provides high specificity, although a lower cutoff value of 10 or 11 (with its high specificity maintained) may be more beneficial when pain attributed to neuropathic mechanisms is suspected in Japanese patients.

Efficacy of a trunk orthosis with joints providing resistive force on low back load during level walking in elderly persons

PURPOSE

The effects of lumbosacral and spinal orthoses on low back pain and gait are not exactly clear. We previously developed a trunk orthosis with joints providing resistive force on low back load to decrease such load, and confirmed its positive effects during level walking in healthy young adults. Therefore, we aimed to determine the efficacy of this trunk orthosis during level walking in healthy elderly subjects.

METHODS

Fifteen community-dwelling elderly subjects performed level walking at a self-selected speed without an orthosis, with our orthosis, and with a lumbosacral orthosis. Kinematic and kinetic data were recorded using a three-dimensional motion analysis system, and erector spinae activity was recorded by electromyography.

RESULTS

When comparing the three conditions, our orthosis showed the following effects: it decreased the peak extension moment, increased the peak flexion moment, decreased the lateral bending angle, increased the peak thoracic extension angle, and had significantly lower erector spinae activity and significantly larger peak pelvic forward tilt angles.

CONCLUSION

Our orthosis with joints providing resistive force decreased low back load and modified trunk and pelvis alignments during level walking in healthy elderly people.

Diagnosing Discogenic Low Back Pain Associated with Degenerative Disc Disease Using a Medical Interview

Purposes

To evaluate the usefulness of our original five questions in a medical interview for diagnosing discogenic low back pain (LBP), and to establish a support tool for diagnosing discogenic LBP.

Materials and Methods

The degenerative disc disease (DDD) group (n = 42) comprised patients diagnosed with discogenic LBP associated with DDD, on the basis of magnetic resonance imaging findings and response to analgesic discography (discoblock). The control group (n = 30) comprised patients with LBP due to a reason other than DDD. We selected patients from those who had been diagnosed with lumbar spinal stenosis and had undergone decompression surgery without fusion. Of them, those whose postoperative LBP was significantly decreased were included in the control group. We asked patients in both groups whether they experienced LBP after sitting too long, while standing after sitting too long, squirming in a chair after sitting too long, while washing one’s face, and in the standing position with flexion. We analyzed the usefulness of our five questions for diagnosing discogenic LBP, and performed receiver operating characteristic (ROC) curve analysis to develop a diagnostic support tool.

Results

There were no significant differences in baseline characteristics, except age, between the groups. There were significant differences between the groups for all five questions. In the age-adjusted analyses, the odds ratios of LBP after sitting too long, while standing after sitting too long, squirming in a chair after sitting too long, while washing one’s face, and in standing position with flexion were 10.5, 8.5, 4.0, 10.8, and 11.8, respectively. The integer scores were 11, 9, 4, 11, and 12, respectively, and the sum of the points of the five scores ranged from 0 to 47. Results of the ROC analysis were as follows: cut-off value, 31 points; area under the curve, 0.92302; sensitivity, 100%; and specificity, 71.4%.

Conclusions

All five questions were useful for diagnosing discogenic LBP. We established the scoring system as a support tool for diagnosing discogenic LBP.

The impact of depression among chronic low back pain patients in Japan

Background

Chronic low back pain (CLBP) is associated with significant disability and reductions in health related quality of life (HRQoL), which can negatively impact overall function and productivity. Depression is also associated with painful physical symptoms, and is often present in patients with chronic pain. However, the incremental burden associated with depression or symptoms of depression among CLBP patients is not well understood. The objective of this study was to investigate the impact of depression on HRQoL in CLBP and to assess the relationship between depression and work impairment and healthcare use among CLBP patients in Japan.

Methods

Data were extracted from the 2014 Japan National Health and Wellness Survey (N = 30,000). CLBP was defined by report of diagnosed low back pain ≥3 months duration. Depression was assessed using the Patient Health Questionnaire (PHQ-9). Measurements assessed included pain, HRQoL, labor force participation, work productivity and healthcare utilization. Patients with depression (PHQ-9 ≥ 10) were compared to patients without depression (PHQ-9 < 10) using t-tests for continuous and count variables and chi-square for categorical variables, which were followed by generalized linear models adjusted for covariates. The association between presenteeism and other patient outcomes and characteristics was analysed using nonparametric correlations (Spearman’s rho).

Results

Depressed CLBP patients had significantly more severe pain and higher levels of pain compared with patients without depression (P < 0.001). Depression was associated with worse HRQoL in CLBP patients. Presenteeism, overall work impairment and activity impairment were 1.8, 1.9 and 1.7 times as high, respectively, among those with depression relative to those without depression. CLBP patients with depression had almost twice as many healthcare provider visits in 6 months than those without depression. The pattern of results remained consistent after adjustment for sociodemographic and general health characteristics. Analysis also indicated presenteeism was closely related to overall work impairment (rho = 0.99).

Conclusions

Depression among CLBP patients in Japan was associated with higher pain scores and lower HRQoL scores, as well as lower labor productivity and increased healthcare use. Screening for depression in CLBP patients should be an essential part of CLBP patient care.

The Association between the Cross-Sectional Area of the Dural Sac and Low Back Pain in a Large Population: The Wakayama Spine Study

OBJECTIVE

The purpose of this study was to evaluate the relations between the degree of encroachment, measured as the cross-sectional area of the dural sac, and low back pain in a large population.

METHODS

In this cross-sectional study, data from 802 participants (247 men, 555 women; mean age, 63.5 years) were analyzed. The measurement of the cross-sectional area of the dural sac from the level of L1/2 to L4/5 was taken using axial T2-weighted images. The minimum cross-sectional area was defined as the cross-sectional area of the dural sac at the most constricted level in the examined spine. Participants were divided into three groups according to minimum cross-sectional area measurement quartiles (less than the first quartile, between the first and third quartiles, and greater than the third quartile). A multivariate logistic regression analysis was used to estimate the association between the minimum cross-sectional area and the prevalence of low back pain.

RESULTS

The mean minimum cross-sectional area was 117.3 mm2 (men: 114.4 mm2; women: 118.6 mm2). A logistic regression analysis adjusted for age, sex, body mass index, and other confounding factors, including disc degeneration, showed that a narrow minimum cross-sectional area (smaller than the first quartile) was significantly associated with low back pain (odds ratio, 1.78; 95% confidence interval, 1.13-2.80 compared to the wide minimum cross-sectional area group: minimum cross-sectional area greater than the third quartile measured).

CONCLUSION

This study showed that a narrow dural sac cross-sectional area was significantly associated with the presence of low back pain after adjustment for age, sex, and body mass index. Further investigations that include additional radiographic findings and psychological factors will continue to elucidate the causes of low back pain.

Psychometric Assessment of the Japanese Version of the Zurich Claudication Questionnaire (ZCQ): Reliability and Validity

Purpose

The Zurich Claudication Questionnaire (ZCQ) is a self-administered measure to evaluate symptom severity, physical function, and surgery satisfaction in lumbar spinal stenosis (LSS). The purpose of this study is to assess the psychometric properties of the Japanese ZCQ in LSS patients.

Methods

LSS patients who are scheduled to undergo surgery were recruited from 12 facilities. Responses to several questionnaires, including the Japanese ZCQ; the visual analogue scale (VAS) to evaluate the degree of pain in the buttocks/legs, numbness in the buttocks/legs, and low back pain; the Oswestry Disability Index (ODI); and the SF-36v2, were collected before surgery and again 3 months after surgery (the post-surgery ZCQ was administered twice for test-retest reliability). For reliability, test-retest reliability was evaluated using the intra-class coefficient (ICC) and internal consistency was evaluated using Cronbach’s alpha coefficient. Concurrent validity was assessed using Spearman’s correlation coefficients between the Japanese ZCQ and other questionnaires. Effect size (ES) and standard response mean were calculated for responsiveness. All analyses were performed individually for the Japanese ZCQ symptom, function, and satisfaction domains.

Results

Data from 180 LSS patients were used in this analysis. The ICCs were 0.81, 0.89, and 0.88 and Cronbach’s alpha coefficients were 0.78, 0.84, and 0.92 for the Japanese ZCQ symptom, function, and satisfaction domains, respectively. Regarding the concurrent validity, strong correlations (±0.5) were demonstrated between the Japanese ZCQ domains and the VAS leg pain, ODI, and SF-36v2 physical functioning or bodily pain, whereas correlations were approximately 0.3 in scales measuring other symptoms that are less related to symptom, function, or satisfaction domains. ESs showed high values for the ZCQ symptom and function domains (-1.73 for both).

Conclusions

These psychometric assessments demonstrate that the Japanese ZCQ is a psychometrically reliable and valid measure in LSS. The Japanese ZCQ can evaluate both multi-dimensional aspects and the level of surgery satisfaction.

Descriptive Epidemiology of Somatising Tendency: Findings from the CUPID Study

Somatising tendency, defined as a predisposition to worry about common somatic symptoms, is importantly associated with various aspects of health and health-related behaviour, including musculoskeletal pain and associated disability. To explore its epidemiological characteristics, and how it can be specified most efficiently, we analysed data from an international longitudinal study. A baseline questionnaire, which included questions from the Brief Symptom Inventory about seven common symptoms, was completed by 12,072 participants aged 20-59 from 46 occupational groups in 18 countries (response rate 70%). The seven symptoms were all mutually associated (odds ratios for pairwise associations 3.4 to 9.3), and each contributed to a measure of somatising tendency that exhibited an exposure-response relationship both with multi-site pain (prevalence rate ratios up to six), and also with sickness absence for non-musculoskeletal reasons. In most participants, the level of somatising tendency was little changed when reassessed after a mean interval of 14 months (75% having a change of 0 or 1 in their symptom count), although the specific symptoms reported at follow-up often differed from those at baseline. Somatising tendency was more common in women than men, especially at older ages, and varied markedly across the 46 occupational groups studied, with higher rates in South and Central America. It was weakly associated with smoking, but not with level of education. Our study supports the use of questions from the Brief Symptom Inventory as a method for measuring somatising tendency, and suggests that in adults of working age, it is a fairly stable trait.

Influence of work-related psychosocial factors on the prevalence of chronic pain and quality of life in patients with chronic pain

OBJECTIVES

Working is a common cause of chronic pain for workers. However, most of them need to continue working despite the pain in order to make a living unless they get a sick leave or retirement. We hypothesised that the therapeutic effect of vocational rehabilitation may depend on psychosocial factors related to the workplace. To test this hypothesis, we examined the association of work-related psychosocial factors with the prevalence of chronic pain or health-related quality of life (HRQoL) among workers with chronic pain.

METHODS

We examined 1764 workers aged 20-59 years in the pain-associated cross-sectional epidemiological survey in Japan. The outcomes were (1) chronic pain prevalence among all workers and (2) low Euro QoL (EQ-5D <0.76; mean value of the current study) prevalence among workers with chronic pain according to the degree of workplace social support and job satisfaction. Workplace social support and job satisfaction were measured using the Brief Job Stress Questionnaire. Multivariable-adjusted ORs were calculated using a logistic regression model including age, sex, smoking, exercise, sleep time, work hours, body mass index, personal consumption expenditure, intensity of pain and the presence of severe depressive symptoms.

RESULTS

Chronic pain prevalence was higher among males reporting job dissatisfaction compared with those reporting job satisfaction. No difference was observed among women. Chronic pain prevalence did not differ between workers of either sex reporting poor workplace social support compared with those reporting sufficient support. Among workers with chronic pain, low HRQoL was more frequent in those reporting job dissatisfaction. Similarly, low HRQoL was more frequent in patients with chronic pain reporting poor social support from supervisors or co-workers compared with patients reporting sufficient support.

CONCLUSIONS

Work-related psychosocial factors are critical for HRQoL in patients with chronic pain.

Effect of pelvic forward tilt on low back compressive and shear forces during a manual lifting task

[Purpose] To examine the effect of an instruction to increase pelvic forward tilt on low back load during a manual lifting task in the squat and stoop postures. [Subjects] Ten healthy males who provided informed consent were the subjects. [Methods] Kinetic and kinematic data were captured using a 3-dimensional motion analysis system and force plates. Low back compressive and shear forces were chosen as indicators of low back load. The subjects lifted an object that weighed 11.3 kg, under the following 4 conditions: squat posture, stoop posture, and these lifting postures along with an instruction to increase pelvic forward tilt. [Results] In the squat posture, the instruction to increase pelvic forward tilt reduced the low back compression and shear forces. [Conclusion] The present results suggest that a manual lifting task in the squat posture in combination with an instruction to increase pelvic forward tilt can decrease low back compression and shear forces, and therefore, might be an effective preventive method for low back pain in work settings.

Psychometric Properties of the Japanese Version of the STarT Back Tool in Patients with Low Back Pain

Background and Objective

The STarT Back Tool uses prognostic indicators to classify patients with low back pain into three risk groups to guide early secondary prevention in primary care. The present study aimed to evaluate the psychometric properties of the Japanese version of the tool (STarT-J).

Methods

An online survey was conducted among Japanese patients with low back pain aged 20–64 years. Reliability was assessed by examining the internal consistency of the overall and psychosocial subscales using Cronbach’s alpha coefficients. Spearman’s correlation coefficients were used to evaluate the concurrent validity between the STarT-J total score/psychosocial subscore and standard reference questionnaires. Discriminant validity was evaluated by calculating the area under the curves (AUCs) for the total and psychosocial subscale scores against standard reference cases. Known-groups validity was assessed by examining the relationship between low back pain-related disability and STarT-J scores.

Results

The analysis included data for 2000 Japanese patients with low back pain; the mean (standard deviation [SD]) age was 47.7 (9.3) years, and 54.1% were male. The mean (SD) STarT-J score was 2.2 (2.1). The Cronbach’s alpha coefficient was 0.75 for the overall scale and 0.66 for the psychosocial subscale. Spearman’s correlation coefficients ranged from 0.30 to 0.59, demonstrating moderate to strong concurrent validity. The AUCs for the total score ranged from 0.65 to 0.83, mostly demonstrating acceptable discriminative ability. For known-groups validity, participants with more somatic symptoms had higher total scores. Those in higher STarT-J risk groups had experienced more low back pain-related absences.

Conclusions

The overall STarT-J scale was internally consistent and had acceptable concurrent, discriminant, and known-groups validity. The STarT-J can be used with Japanese patients with low back pain.

Can standing back extension exercise improve or prevent low back pain in Japanese care workers?

BACKGROUND

We suggested a standing back extension exercise 'One Stretch' based on the McKenzie method, to examine the ability to improve or prevent low back pain (LBP) in Japanese care workers.

METHODS

We conducted a single-center, non-randomized, controlled study in Japan. Care workers in an intervention group received an exercise manual and a 30-minute seminar on LBP and were encouraged with a group approach, while care workers in a control group were given only the manual. All care workers answered questionnaires at the baseline and end of a 1-year study period. The subjective improvement of LBP and compliance with the exercise were evaluated.

RESULTS

In all, 64 workers in the intervention group and 72 in the control group participated in this study. More care workers in the intervention group exercised regularly and improved or prevented LBP than in the control group (P = 0·003 and P<0·0001, respectively). In the intervention group, none had a first medical consultation or were absent from disability for LBP by the end of the study period.

CONCLUSION

The exercise 'One Stretch' would be effective to improve or prevent LBP in care workers. Our group approach would lead to better compliance with the exercise.

Predictive Factors for Subjective Improvement in Lumbar Spinal Stenosis Patients with Nonsurgical Treatment: A 3-Year Prospective Cohort Study

Objective

To assess the predictive factors for subjective improvement with nonsurgical treatment in consecutive patients with lumbar spinal stenosis (LSS).

Materials and Methods

Patients with LSS were enrolled from 17 medical centres in Japan. We followed up 274 patients (151 men; mean age, 71 ± 7.4 years) for 3 years. A multivariable logistic regression model was used to assess the predictive factors for subjective symptom improvement with nonsurgical treatment.

Results

In 30% of patients, conservative treatment led to a subjective improvement in the symptoms; in 70% of patients, the symptoms remained unchanged, worsened, or required surgical treatment. The multivariable analysis of predictive factors for subjective improvement with nonsurgical treatment showed that the absence of cauda equina symptoms (only radicular symptoms) had an odds ratio (OR) of 3.31 (95% confidence interval [CI]: 1.50–7.31); absence of degenerative spondylolisthesis/scoliosis had an OR of 2.53 (95% CI: 1.13–5.65); <1-year duration of illness had an OR of 3.81 (95% CI: 1.46–9.98); and hypertension had an OR of 2.09 (95% CI: 0.92–4.78).

Conclusions

The predictive factors for subjective symptom improvement with nonsurgical treatment in LSS patients were the presence of only radicular symptoms, absence of degenerative spondylolisthesis/scoliosis, and an illness duration of <1 year.