Radiographic knee osteoarthritis severity has no impact on fall risk: the locomotive syndrome and health outcomes in the aizu cohort study (LOHAS): a cross-sectional study.

BACKGROUND: To investigate factors that have an impact on the risk of falls and determine whether radiographic knee osteoarthritis (KOA) is a factor involved in falls independent of knee pain, psychological factors, and physical function. METHODS: A cross-sectional analysis was conducted on 1083 subjects for the 2009 Locomotive Syndrome and Health Outcomes in the Aizu Cohort Study (LOHAS). A logistic regression analysis was performed to examine the relationship between radiographic KOA and fall history. RESULTS: Fall history was significantly associated with the severity of knee pain. Compared to subjects with no knee pain, the odds ratio (OR) was 1.53 times higher in the subjects with mild knee pain (95% confidence interval [CI]: 1.04-2.25), 1.69 times higher in those with moderate knee pain (95%CI: 1.03-2.79), and 2.98 times higher in those with severe knee pain (95%CI: 1.67-5.30). In subjects with depression, the OR was 1.91 (95%CI: 1.25-2.92), and in those with decreased mobility, the OR was 1.70 (95%CI: 1.08-2.69). Age, gender, knee crepitus, BMI, OLST, and sleeping pill use were not significantly associated with fall risk. In a multivariate analysis, radiographic KOA severity was not significantly associated with fall risk (OR 0.81, 95%CI 0.44-1.50 in mild OA; OR 1.10, 95%CI 0.57-2.14 in severe OA). CONCLUSION: Knee pain, decreased mobility, and depression, but not the radiographic KOA severity, were significantly associated with a fall risk. Regardless of the individual's radiographic KOA severity, the risk of falls may be reduced by treating his/her knee pain, mobility problems, and/or psychological factors.

Gender Diversity of the Japanese Society for Spine Surgery and Related Research Annual Meetings from 2013 to 2022.

Introduction: There are no reports that have examined the annual trends of the percentage of women who are members of the Japanese Society for Spine Surgery and Related Research (JSSR) or their roles at annual meetings. Furthermore, the status of gender diversity in the JSSR remains unclear. This study aims to identify gender diversity in the JSSR by quantifying the role of women at annual meetings over the past decade. Methods: We performed a retrospective review to explore gender role in the JSSR annual meeting by examining the meeting programs for 2013-2022. The gender ratios were surveyed each year for the following: (1) first authors of general application abstracts (oral and poster), (2) meeting guest speakers, (3) meeting moderators, and (4) program editors of the abstracts. We also investigated the availability of gender equality symposiums. Results: The percentage of women applying (1.1%-2.1%) and those who were invited as participants [guest speaker (0%-0.9%), moderator (0%-5.8%), and program editor (0%-0.6%)] at the annual JSSR meetings was low, with no significant increase over the past decade. In addition, there has never been a symposium promoting gender equality at the annual JSSR meeting. Conclusions: Our findings suggest that a strong and active role for institutional leaders and senior members to support the scholarly activities of women spine surgeons is important for adopting gender diversity in the JSSR academia. The absence of gender equality symposiums and the few invited women participants at the JSSR annual meeting may be due to a lack of gender diversity awareness among conference organizers or unconscious gender bias. Monitoring the role of women in the JSSR annual meetings may solve the gender diversity problem.

Differences in macrophage expression in induced membranes by fixation method - Masquelet technique using a mouse's femur critical-sized bone defect model.

INTRODUCTION: Masquelet's induced membrane technique (MIMT) is an emerging method for reconstructing critical-sized bone defects. However, an incomplete understanding of the underlying biological and physical processes hinders further optimization. This study investigated the effect of different bone-defect fixation methods on macrophage expression in an induced membrane using a novel mouse plate-fixed Masquelet model. METHODS: Mice were divided into Plate-fixed Masquelet (P-M), Intramedullary-fixed Masquelet (IM-M), Plate-fixed Control (P-C), and Back subfascial (B) groups. In the P-M and IM-M groups, a polymethylmethacrylate (PMMA) spacer was implanted into a 3 mm bone defect, while the defect in the P-C group remained unfilled. In group B, a spacer was inserted under the back fascia to examine membrane formation caused by a simple foreign body reaction. Tissues were collected at 1, 2, and 4 weeks postoperatively. Hematoxylin and eosin (H&E) staining and immunohistochemistry (CD68 and CD163: macrophage markers) were performed to assess macrophage expression within the membrane. qPCR was performed to measure the expression of CD68, CD163, and fibroblast growth factor 2 (FGF2). RESULTS: Four weeks post-operation, the P-M group presented with minimal callus growth, whereas the IM-M group exhibited vigorous growth. The P-M and IM-M groups displayed a tri-layered membrane structure, which is consistent with the results of previous studies. The IM-M group had significantly thicker membranes, whereas the P-M group exhibited higher expression levels of CD68, CD163, and FGF2. Group P-C showed no osteogenesis, whereas group B maintained a thin, cell-dense membrane structure. The P-M group consistently showed higher gene expression levels than the P-C and P-B groups. CONCLUSION: This study introduced a mouse plate fixation model for MIMT. The induced membranes could be adequately evaluated in this model. Induced membranes are formed by foreign body reactions to PMMA spacers; however, their properties are clearly different from those of simple foreign body reaction capsules and granulation tissues that infiltrate bone defects, suggesting that they are more complex tissues. The characteristics and expression of macrophages within these induced membranes varied according to the bone defect fixation method.

Assessment of Lumbar Spinal Stenosis as a Risk Factor for Development of Sleep Disorder: The Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS).

Purpose: Insomnia has been reported to coexist with various musculoskeletal disorders. Although lumbar spinal stenosis (LSS) is the most frequently operated on spinal disease, the causal relationship between LSS and development of sleep disorders remains unclear due to lack of longitudinal studies. This study aimed to determine whether LSS was a risk factor for developing new sleep disorders, primarily insomnia, using a prospective cohort of community residents. Patients and Methods: This study was a prospective cohort study. Participants aged ≥65 years from the "Locomotive Syndrome and Health Outcomes in Aizu Cohort Study (LOHAS)" conducted in 2008 formed our study population. LSS was diagnosed using the self-administered, self-reported history questionnaire, a validated diagnostic support tool for LSS. Sleep disorder was investigated using a questionnaire during the 2-year follow-up. The impact of LSS on sleep disorder onset was analyzed after adjusting for potential confounders, such as age, sex, obesity, hypertension, diabetes, depression, and smoking habits, using propensity score matching. Results: Of the 489 participants who were followed up for two years, 38 (7.8%) had newly developed a sleep disorder in 2010. After adjusting for confounding factors, a comparison of 133 participants each in the control and LSS groups showed significantly higher frequency of new-onset sleep disorders (19 [14.3%] in the LSS group versus 6 [4.5%] in the control group). Conclusion: LSS was found to be an independent risk factor for sleep disorders.

Preoperative factors affecting the two-year postoperative patient-reported outcome in single-level lumbar grade I degenerative spondylolisthesis.

Background: The choice of operative method for lumbar spinal stenosis with Meyerding grade I degenerative spondylolisthesis remains controversial. The purpose of this study was to identify the preoperative factors affecting the 2-year postoperative patient-reported outcome in Meyerding grade I degenerative spondylolisthesis. Methods: Seventy-two consecutive patients who had minimally invasive decompression alone (D group; 28) or with fusion (DF group; 44) were enrolled. The parameters investigated were the Japanese Orthopaedic Association back pain evaluation questionnaire as patient-reported assessment, and L4 slippage (L4S), lumbar lordosis (LL), and lumbar axis sacral distance (LASD) as an index of sagittal alignment for radiological evaluation. Data collected prospectively at 2 years postoperatively were examined by statistical analysis. Results: Sixty-two cases (D group; 25, DF group; 37) were finally evaluated. In multiple logistic regression analysis, preoperative L4S and LASD were extracted as significant preoperative factors affecting the 2-year postoperative outcome. Patients with preoperative L4S of 6 mm or more have a lower rate of improvement in lumbar spine dysfunction due to low back pain (risk ratio=0.188, p=.043). Patients with a preoperative LASD of 30 mm or more have a higher rate of improvement in lumbar dysfunction due to low back pain (risk ratio=11.48, p=.021). The results of multiple logistic analysis by operative method showed that there was a higher rate of improvement in lumbar spine dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more in DF group (risk ratio=172.028, p=.01). Conclusions: Preoperative L4S and LASD were extracted as significant preoperative factors affecting patient-reported outcomes at 2 years postoperatively. Multiple logistic analyses by the operative method suggested that DF may be advantageous in improving lumbar dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more.

Potential influencing factor on health-related quality of life in Japanese with knee osteoarthritis: the Locomotive syndrome and Health outcome in Aizu cohort Study (LOHAS).

PURPOSE: Several studies have investigated the factors that influence health-related quality of life in patients with knee osteoarthritis (KOA). This study aimed to identify and investigate the degree of involvement of potential factors influencing health-related quality of life (HRQOL) in an aged population with or without KOA. METHODS: This multi-centered study included 651 participants who underwent health checkups in rural areas of Japan in 2010. The association between three component summary score of short-form 12 (physical component summary; PCS, mental component summary; MCS, and role-social component summary; RCS) and covariates were investigated using multiple linear regression model and calculated the scaled estimated regression coefficient. RESULTS: Decreasing mobility, severity of knee pain, high pain-related self-efficacy (PSE), older age, high functional self-efficacy (FSE), and female gender had significant effect on PCS (p < 0.05). However, radiographic KOA had no influence on PCS. Presence of depression and body mass index had a significant influence on the MCS (p < 0.05). Decreasing mobility, presence of depression, PSE and older age had significant influence on the RCS (p < 0.05). CONCLUSION: Our study results showed that physical, mental, and role/social QOL were affected by different influencing factors. Physical QOL was strongly influenced by subjective pain, physical performance, and self-efficacy, whereas radiographic KOA had no such effect. Depressive mood is associated with both mental and role/social QOL. The role/social QOL was predominantly affected by physical function and pain-related self-efficacy. Taking measure to improving functional ability and mental status might be the key factor to improve HRQOL in patient with KOA. LEVEL OF EVIDENCE: Level 3: Epidemiologic cross-sectional study (prognostic study).

Relationship between dysphagia and motor function in community-dwelling older people.

AIM: Dysphagia is a problem typically associated with aging. The aim was to investigate the relationship between dysphagia and motor function using a simple assessment method that can be performed in the community setting, and to promote the early detection and prevention of dysphagia. METHODS: Data from the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS) were used. Those aged ≥65 years were included. Motor function was assessed using a grip strength test, single limb standing test (SLS), and timed up and go test (TUG). Swallowing function was assessed using the Japanese version of the 10-item Eating Assessment Tool (EAT-10). The association between motor function and swallowing function was analyzed. RESULTS: In total, 1732 participants were included. In logistic regression modes in which grip strength, SLS, and TUG results were included separately, the odds ratio for dysphagia increased by 1.08 (P = 0.001) for each 1-kg decrease in grip strength, and increased by 1.15 (P < 0.001) for each 1-s increase in TUG time. No association was found for SLS. In the model in which grip strength and TUG were included simultaneously, the odds ratio for dysphagia increased by 1.06 (P = 0.01) in grip strength, and increased by 1.11 (P = 0.009) in TUG time. CONCLUSION: Our results suggest that skeletal muscle strength and dynamic balance function are associated with dysphagia in community-dwelling older people. Geriatr Gerontol Int 2023; 23: 603-608.

Relationship between lumbar facet joint osteoarthritis and comorbidities: A cross-sectional study in the Japanese community.

BACKGROUND: Few epidemiological studies have evaluated associations between lumbar facet joint (LFJ) osteoarthritis (OA) and comorbidities. This study aimed to investigate the prevalence of LFJ OA in a Japanese community population and associations between LFJ OA and underlying diseases, including lower extremity OA. METHODS: This epidemiological cross-sectional study evaluated LFJ OA in 225 Japanese community residents (81 males, 144 females; median age, 66 years) using magnetic resonance imaging (MRI). LFJ OA from L1-L2 to L5-S1 was evaluated using a 4-grade classification. Associations between LFJ OA and comorbidities were examined using multiple logistic regression analyses adjusting for age, sex, and body mass index. RESULTS: Prevalences of LFJ OA were 28.6% at L1-L2, 36.4% at L2-L3, 48.0% at L3-L4, 57.3% at L4-L5, and 44.2% at L5-S1. Males were significantly more likely to have LFJ OA at several spinal levels (L1-L2 45.7% vs 18.9%, p < 0.001; L2-L3 46.9% vs 30.6%, p < 0.05; L4-L5 67.9% vs 51.4%, p < 0.05). LFJ OA was present in 50.0% of residents <50 years old, 68.4% at 50-59 years old, 86.3% at 60-69 years old, and 85.1% at ≥70 years old. Multiple logistic regression analysis showed no associations between LFJ OA and comorbidities. CONCLUSIONS: The prevalence of LFJ OA as evaluated by MRI was >85% at ≥60 years old and highest at the L4-L5 spinal level. Males were significantly more likely to have LFJ OA at several spinal levels. Comorbidities were not associated with LFJ OA.

How long will it take to reach the gender diversity goal for orthopaedics in Japan?

BACKGROUND: In Japan, orthopaedics is one of the medical fields with the lowest proportion of women. This study analyses the change in gender diversity over the past decade and estimates the time required to achieve the 30% gender diversity goal, according to the critical mass in Japan in 2020. METHODS: We investigated the demographic composition of orthopaedic surgeons in 2020 by age group, the gender ratio of the main clinical fields from 2010 to 2020, and estimated the time required for the bottom 10 (i.e., least diverse) medical departments in Japan to reach the proportion of 30% women. We used simple linear regression analyses to clarify the number of years. RESULTS: In 2020, the population pyramid of orthopaedic surgeons showed that those in their 50s were the largest component with 24.1%, followed by those in their 40s and 30s with 22.3% and 19.4%, respectively. The percentage of women orthopaedic surgeons increased slightly from 4.1% in 2010 to 5.7% in 2020. This means that to achieve the proportion of 30% women at the current annual increase rate, orthopaedics would require up to 160 years, cardiovascular 149 years, and neurosurgery 135 years. CONCLUSION: Contrary to the recent increase in the number of women physicians, there has been only a slight increase in the number of women orthopaedic surgeons over the past decade. Moreover, the number of young male orthopaedic surgeons has decreased. As current orthopaedic surgeons age and retire, Japan will soon face an overall shortage of orthopaedic surgeons. Issues that must still be addressed in Japanese orthopaedics include educating men and women about gender diversity and bias, changing stereotypes about surgical lifestyles, improving work-life balance, and diligent and collaborative efforts at both the individual and community levels.

Generalization of a clinical diagnosis support tool for lumbar spinal stenosis: Can the ankle brachial pressure index be replaced by palpation of the posterior tibial artery in the lumbar spinal stenosis diagnostic support tool? (DISTO project).

BACKGROUND: The Japanese Society for Spine Surgery and Related Research previously developed a diagnostic support tool for lumbar spinal stenosis (LSS-DST). Using the LSS-DST, general physicians can identify potential cases of LSS. However, in the LSS-DST, measurement of the ankle brachial pressure index (ABI) is required to exclude peripheral artery lesions in the lower limbs. We can expect further application of the LSS-DST if we can identify a simpler and easier method than ABI measurement. Therefore, in this large-scale, multicenter, cross-sectional study, we verified whether palpation of the posterior tibial (PT) artery could be used instead of ABI in the LSS-DST. METHODS: This survey was conducted at 2177 hospitals and included 28,883 participants. The sensitivity and specificity of the original LSS-DST method using the ABI and that of the LSS-DST ver2.0 with PT artery palpation were assessed to screen their ability for diagnosing LSS, using the physicians' final diagnosis based on the patients' history, physical examination and radiographic findings as the gold standard. RESULTS: The sensitivity and specificity [95%CI] of the LSS-DST were 88.2% [87.5, 88.8] and 83.9% [83.4, 84.5], respectively, whereas the sensitivity and specificity of the LSS-DST ver2.0 were 87.7% [87.0, 88.3] and 78.3% [77.7, 78.9], respectively, indicating that LSS-DST ver2.0 is a useful screening tool for LSS with good sensitivity. CONCLUSION: When the item of ABI in the LSS-DST is replaced by palpation of the PT artery (LSS-DST ver2.0), its sensitivity is maintained as a screening tool for LSS. LEVEL OF EVIDENCE: Level 3.

Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of lumbar spinal stenosis, 2021 - Secondary publication.

BACKGROUND: The Japanese Orthopaedic Association (JOA) guideline for the management of lumbar spinal stenosis (LSS) was first published in 2011. Since then, the medical care system for LSS has changed and many new articles regarding the epidemiology and diagnostics of LSS, conservative treatments such as new pharmacotherapy and physical therapy, and surgical treatments including minimally invasive surgery have been published. In addition, various issues need to be examined, such as verification of patient-reported outcome measures, and the economic effect of revised medical management of patients with lumbar spinal disorders. Accordingly, in 2019 the JOA clinical guidelines committee decided to update the guideline and consequently established a formulation committee. The purpose of this study was to describe the formulation we implemented for the revision of the guideline, incorporating the recent advances of evidence-based medicine. METHODS: The JOA LSS guideline formulation committee revised the previous guideline based on the method for preparing clinical guidelines in Japan proposed by the Medical Information Network Distribution Service in 2017. Background and clinical questions were determined followed by a literature search related to each question. Appropriate articles based on keywords were selected from all the searched literature. Using prepared structured abstracts, systematic reviews and meta-analyses were performed. The strength of evidence and recommendations for each clinical question was decided by the committee members. RESULTS: Eight background and 15 clinical questions were determined. Answers and explanations were described for the background questions. For each clinical question, the strength of evidence and the recommendation were both decided, and an explanation was provided. CONCLUSIONS: The 2021 clinical practice guideline for the management of LSS was completed according to the latest evidence-based medicine. We expect that this guideline will be useful for all medical providers as an index in daily medical care, as well as for patients with LSS.

Lumbar spinal stenosis is a risk factor for the development of dementia: locomotive syndrome and health outcomes in the Aizu cohort study.

PURPOSE: It remains unclear whether musculoskeletal diseases are risk factors for dementia development. This prospective cohort study of community-dwelling residents aimed to clarify the impact of lumbar spinal stenosis (LSS) on dementia development. METHODS: We included participants aged ≥ 65 years from the Locomotive Syndrome and Health Outcomes in the Aizu cohort study. LSS was diagnosed using the validated LSS diagnostic support tool. Dementia development between 2008 and 2015 was investigated using official long-term care insurance certification data. We analysed the effects of LSS on dementia development after adjusting for potential confounders, like age, sex, diabetes, depressive symptoms, hip and knee joint osteoarthritis, daily activity, and smoking habit. RESULTS: We included 1220 patients in the final analysis. The incidence of dementia was significantly higher in the LSS group [48 of 444 (10.8%)] than in the control group [34 of 776 (4.4%)]. Multivariable analysis using multiple imputations revealed that the confidence interval for the adjusted odds ratio of LSS for dementia development was 1.87 (95% confidence interval; 1.14-3.07). CONCLUSION: We clarified that LSS is an independent risk factor for dementia development. Our findings suggest the importance of considering the risk of dementia in the decision-making process for the treatment of LSS.

Epidemiological Study of Lumbar Spinal Stenosis Symptoms: 10-Year Follow-Up in the Community.

BACKGROUND: Lumbar spinal stenosis (LSS) is one of the important health problems in an aging society because it can significantly impair quality of life (QOL) and active daily living (ADL). However, the natural history or long-term change of LSS symptoms is still unclear. The purpose of this study was to clarify the 10-year course of lumbar spinal stenosis (LSS) symptoms in community-dwelling residents of more than 1000 people with prospective data collection. METHODS: A total of 1149 subjects were analyzed for the time course of LSS symptoms for ten years. LSS symptoms were assessed using a questionnaire specially designed and validated to detect LSS symptoms without image information such as magnetic resonance imaging. RESULTS: The prevalence of positive LSS symptoms was about 16% in the initial survey and 10-year follow-up. Of the subjects who were LSS positive at the initial survey, 40% showed positive LSS symptoms at follow-up and 60% switched to negative LSS symptoms. According to the multivariable logistic regression analysis, severe depression and positive LSS symptoms were extracted as predictors of the presence of LSS symptoms after a 10-year follow-up. CONCLUSION: The statistical predictor of the presence of LSS symptoms at 10 years was the presence of LSS symptoms at the initial survey; however, 60% of those who were positive for LSS symptoms at the initial survey were not determined to have LSS symptoms at the 10-year follow-up. This was the same result as at the 1-year and 6-year follow-up.

Relationship between lumbar disc degeneration on MRI and low back pain: A cross-sectional community study.

PURPOSE: Although an association has been suggested between disc degeneration (DD) and low back pain (LBP), some DD is thought to be an age-related change unrelated to symptoms. Age-inappropriate DD, however, may be associated with LBP. The purpose of this study was to investigate whether there is a difference in LBP and LBP-related quality of life between age-appropriate and age-inappropriate DD, as assessed by magnetic resonance imaging (MRI). PARTICIPANTS AND METHODS: In this cross-sectional study, degenerative change in the lumbar intervertebral discs of 382 subjects (age range, 27-82 years) was evaluated by MRI. Degenerative Disc Disease (DDD) scores were assigned using the Schneiderman classification, as the sum of grades for all intervertebral levels (0-15). We classified subjects into three groups according to age and DDD score: Low DD (mild DD relative to age), Appropriate (age-appropriate DD), and High DD (severe DD relative to age). We compared the three groups in terms of LBP prevalence, LBP intensity, LBP-specific quality of life (QOL) according to the Roland-Morris Disability Questionnaire (RDQ), and the Short Form-36 Item Health Survey (SF-36). RESULTS: Of 382 subjects, there were 35% in the Low DD group, 54% in the Appropriate group, and 11% in the High DD group. There were no significant differences among the groups in terms of prevalence of LBP, LBP intensity, RDQ score, or SF-36 score. CONCLUSION: No association was found between age-inappropriate DD (Low or High DD group) and age-appropriate DD (Appropriate group) in terms of prevalence of LBP, LBP intensity, RDQ, or SF-36.

Impact of lumbar spinal stenosis on metabolic syndrome incidence in community-dwelling adults in Aizu cohort study (LOHAS).

Metabolic syndrome and lumbar spinal stenosis (LSS) are common age-related diseases. However, the causal relationship between them remains unclear. This study aimed to identify the effects of LSS on metabolic syndrome incidence in community-dwelling adults. This prospective cohort study included participants of the Aizu cohort study (LOHAS) aged < 75 years as of 2008. Participants with metabolic syndrome at baseline were excluded. The primary outcome measure was metabolic syndrome incidence, and the main explanatory variable was the presence of LSS, as assessed by a self-reported questionnaire. A multivariate Cox proportional hazard regression model was used to estimate hazard ratios (HRs) for metabolic syndrome incidence during the 6-year follow-up period. Complete-case analyses were compared with the multiple imputation results. Among 1599 participants, 1390 complete cases were analyzed (mean [SD] age 62.3 [9.0] years; females, 734 [52.8%]). Among those participants, 525 (37.8%) developed metabolic syndrome during the follow-up of 3.89 [1.96] years. The presence of LSS was associated with developing metabolic syndrome (HR, 1.41; 95% confidence interval [CI] 1.02-1.95). Multiple imputation results showed similar trends of those having complete-case data (HR, 1.47; 95% CI 1.08-2.00). This finding suggests the importance of prevention and management of LSS in community settings.

The Relationship between Exercise-Induced Low Back Pain, the Fat Infiltration Rate of Paraspinal Muscles, and Lumbar Sagittal Balance.

Introduction: Exercise-induced low back pain (EILBP) is induced during anterior trunk tilting when walking or prolonged standing. In some elderly with chronic LBP, the pain is induced by EILBP. The paraspinal muscles play an important role in supporting the spine; therefore, a dysfunction of back muscles and kyphotic alignment are considered to be associated with EILBP. However, few reports are showing the relationship between EILBP and degenerative muscle changes. This study aimed to clarify the relationship between EILBP, degenerative changes of paraspinal muscles, and spinal alignment in an epidemiological study. Methods: A total of 324 subjects were included in the analysis. The presence of EILBP was determined through a medical interview and physical examination. The subjects underwent lumbar spine magnetic resonance image (MRI) and X-ray. The fat infiltration rate (FIR) of the multifidus, erector spinae, and psoas major were analyzed using MRI. For lumbar sagittal balance, L1 axis S1 distance (LASD) was measured using X-ray images. Multivariate logistic regression analysis was used to analyze the association between the presence of EILBP and FIR or LASD. Results: The prevalence of EILBP was 21% and it increased with age. The subjects with EILBP had statistically higher FIR of the multifidus, erector spinae, and psoas major than those without EILBP. There was a significant association between the presence of EILBP and higher FIR of the erector spinae at L1-2 and L5-S1 (p<0.05). However, there were no significant associations between EILBP and LASD. Conclusions: According to the results in this study, EILBP is not rare and the FIR of the erector spinae is associated with the presence of EILBP.

Diagnostic accuracy of the lumbar spinal stenosis-diagnosis support tool and the lumbar spinal stenosis-self-administered, self-reported history questionnaire.

Despite the applicability of the lumbar spinal stenosis (LSS)-diagnosis support tool (DST) and the LSS-self-administered, self-reported history questionnaire (SSHQ), their diagnostic accuracy has never been compared with that of the well-known North American Spine Society (NASS) clinical description of LSS. This study aimed to compare the diagnostic accuracy of the two diagnostic tools with that of the NASS guidelines' clinical description of LSS in a Japanese secondary care hospital setting. This multicenter cross-sectional study used data from the lumbar spinal stenosis diagnostic support tool (DISTO) project, which was conducted from December 1, 2011 to December 31, 2012. Japanese adults with low back pain (LBP) aged ≥20 years were consecutively included. The reference standard was LSS diagnosed by orthopedic physicians. The diagnostic accuracy of the two support tools was compared. Of 3,331 patients, 1,416 (42.5%) patients were diagnosed with LSS. The NASS clinical description of LSS had a sensitivity of 63.9% and specificity of 89.5%. The LSS-DST and LSS-SSHQ had sensitivities of 91.3% and 83.8% and specificities of 76.0% and 57.6%, respectively, with substantial improvements in sensitivity (P < 0.0001). Similar results were obtained when we limited included patients to those aged >60 years. These findings indicated that the LSS-DST and LSS-SSHQ were more sensitive in screening patients with LBP for a diagnosis of LSS than the NASS clinical description of LSS. This study strongly supports prioritizing the use of either of these two diagnostic support tools for screening.