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Abstract This study aims to investigate the influence of lumbar spine disorders on the development of asymmetric hallux valgus (HV). Data from the fifth survey of the Osteoarthritis/Osteoporosis Against Disability (ROAD) study, a nationwide prospective study in Japan, were analyzed. HV severity was categorized into 4 grades based on the radiographic HV angle, and asymmetric HV was defined as having at least one HV on either side, with a difference of two or more severity grades between the left and right. Controls were matched from both the Normal group (without HV on both sides) and the Symmetric group (HV on at least one side with a difference of one or less severity grades). Univariate analysis assessed lumbar conditions, and multinomial logistic regression analysis explored the association between lumbar spine disorders and asymmetric HV. Among 1997 participants, 27 had asymmetric HV. Univariate analysis revealed a higher incidence of L5 spondylolisthesis and scoliosis in the Asymmetric group. Multinomial logistic regression analysis revealed that scoliosis independently increased the likelihood of asymmetrical HV (Odds ratio [OR] = 3.586, 95%Confidence interval [CI] 1.111–11.582), but showed no significant impact on symmetrical HV (OR 0.910, 95% CI 0.355–2.334). Asymmetric HV is rare but may be associated with lumbar spine disorders, particularly scoliosis.

Abstract Osteoporosis, vertebral fractures, and spinal degenerative diseases are common conditions that often coexist in older adults. This study aimed to determine the factors influencing low back pain and its impact on activities of daily living (ADL) and physical performance in older individuals with multiple comorbidities. This cross-sectional study was part of a large-scale population-based cohort study in Japan, involving 1009 participants who underwent spinal magnetic resonance imaging (MRI) to assess cervical cord compression, radiographic lumbar spinal stenosis, and lumbar disc degeneration. Vertebral fractures in the thoracolumbar spine were evaluated using sagittal MRI with a semi-quantitative method. Bone mineral density was measured using dual-energy X-ray absorptiometry. Low back pain, Oswestry Disability Index (ODI), and physical performance tests, such as one-leg standing time, five times chair-stand time, maximum walking speed, and maximum step length, were assessed. Using clinical conditions as objective variables and image evaluation parameters as explanatory variables, multiple regression analysis showed that vertebral fractures were significantly associated with low back pain and ODI. Vertebral fractures and osteoporosis significantly impacted physical performance, whereas osteoporosis alone did not affect low back pain or ODI. Our findings contribute to new insights into low back pain and its impact on ADL and physical performance.

Abstract Pain is a global health problem that leads to sedentary behavior and tends to cause negative emotion. In contrast, exercise is widely recommended for a health promotion, while pain often worsens with physical activity. Although exercise therapy is often prescribed to people with pain, the mechanisms of exercise effect on pain remains unclear. In this study, we tried to identify a universal association factor between regular exercise and pain intensity utilizing a cross-sectional web-based survey involving 52,353 adult participants from a large national study conducted in Japan. Using principal component analysis, we uncovered a mediation model of exercise effect on pain through psychological components. Analyses were performed in half of the population with pain (n = 20,330) and validated in the other half (n = 20,330), and showed that high-frequency exercise had a significant association with reduction in pain intensity. We also found Negative Affect and Vigor, two psychological components, are fully associating the exercise effect on pain (indirect effect = − 0.032, p

Abstract Femoroacetabular impingement has increasingly been recognized as a cause of primary hip osteoarthritis; however, its epidemiological indications remain unclear. We aimed to clarify the epidemiological indications and factors associated with cam deformity in a large-scale population-based cohort in Japan. Overall, 1480 participants (2960 hips) (491 men, 989 women; mean age, 65.3 years) analyzed in the third survey of the Research on Osteoarthritis/Osteoporosis Against Disability study were included. The α angle and spinopelvic parameters (lumbar lordosis, sacral slope, pelvic tilt, and pelvic incidence) were radiographically measured. Cam deformity was defined as α angle ≥ 60°. Overall, the cam deformity prevalence was 147/2960 (5.0%). Cam deformity prevalence tended to increase with age; in the univariate analysis, a higher percentage of men was observed in the group with cam deformity than in the group without it. No relationship was observed between cam deformity and hip pain. Factors associated with α angle were examined via multiple regression analysis for each gender; α angle was significantly associated with age and BMI in each gender. The α angle and PT were correlated in women. Thus, α angle and cam deformity prevalence increase with age in Japanese individuals. Accordingly, cam deformity can be considered a developmental disease.

Objective: Considering the joint space width and osteophyte area (OPA) of the knee joints of Japanese adults, this study elucidated the ten-year trends in medial minimum joint space width (mJSW) and OPA using data of two independent cohorts from a population-based cohort study. Methods: The baseline survey of the Research on Osteoarthritis/Osteoporosis Against Disability study was conducted from 2005 to 2007; 2975 participants (1041 men, 1934 women) completed all knee osteoarthritis (OA) examinations. The fourth survey was performed from 2015 to 2016; distinct 2445 participants (764 men, 1681 women) completed identical examinations. The medial mJSW and medial tibial OPA were measured bilaterally using an automated system. Results: The mean medial mJSW (standard deviation) was 3.22 (0.96) mm and 2.65 (0.95) mm at baseline and 3.81 (1.20) mm and 3.13 (1.15) mm in the fourth survey for men and women, respectively. The mean medial mJSW in the fourth survey was significantly greater in both men and women in all age groups than at baseline (p ​

Abstract Background and Aim To date, no randomized trials have compared the efficacy of 7‐day vonoprazan, amoxicillin, and metronidazole triple therapy (VAM) versus 7‐day vonoprazan, amoxicillin, and clarithromycin triple therapy (VAC) as a first‐line treatment for Helicobacter pylori eradication. This study was performed to compare the efficacy of VAM and VAC as first‐line treatments. Methods This prospective multicenter randomized trial was performed in Japan and involved 124 H. pylori‐positive patients without a history of eradication. Patients without antibiotic resistance testing of H. pylori were eligible. The patients were randomized to receive either VAC (vonoprazan 20 mg + amoxicillin 750 mg + clarithromycin 200 or 400 mg twice a day) or VAM (vonoprazan 20 mg + amoxicillin 750 mg + metronidazole 250 mg twice a day) for 7 days, with stratification by age and sex. Eradication success was evaluated using the 13C‐urea breath test. We evaluated safety using patient questionnaires (UMIN000025773). Results The intention‐to‐treat and per‐protocol eradication rates of VAM were 91.3% (95% confidence interval [CI], 82.0–96.7%) and 92.6% (95% CI, 83.7–97.6%), respectively, and those of VAC were 89.1% (95% CI, 77.8–95.9%) and 96.1% (95% CI, 86.5–99.5%), respectively. No significant difference was observed between VAM and VAC in either analysis (P = 0.76 and P = 0.70, respectively). Abdominal fullness was more frequent in patients who received VAM than VAC. Conclusions These findings suggest that VAM as a first‐line treatment in Japan can be categorized as grade B (intention‐to‐treat cure rate of 90–95%) and have potential as a first‐line national insurance ‐approved regimen.

Abstract Some older adults with spinal deformity maintain standing posture via pelvic compensation when their center of gravity moves forward. Therefore, evaluations of global alignment should include both pelvic tilt (PT) and seventh cervical vertebra-sagittal vertical axis (C7-SVA). Here, we evaluate standing postures of older adults using C7-SVA with PT and investigate factors related to postural abnormality. This cross-sectional study used an established population-based cohort in Japan wherein 1121 participants underwent sagittal whole-spine radiography in a standing position and bioelectrical impedance analysis for muscle mass measurements. Presence of low back pain (LBP), visual analog scale (VAS) of LBP, and LBP-related disability (Oswestry Disability Index [ODI]) were evaluated. Based on the PT and C7-SVA, the participants were divided into four groups: normal, compensated, non-compensated, and decompensated. We defined the latter three categories as “malalignment” and examined group characteristics and factors. There were significant differences in ODI%, VAS and prevalence of LBP, and sarcopenia among the four groups, although these were non-significant between non-compensated and decompensated groups on stratified analysis. Moreover, the decompensated group was significantly associated with sarcopenia. Individuals with pelvic compensation are at increased risk for LBP and related disorders even with the C7-SVA maintained within normal range.

Abstract Background While fear of movement is an important predictor of pain and disability in osteoarthritis (OA), its impact on patients with hip OA remains uncertain. This study aimed to determine whether fear of movement, evaluated by the Tampa Scale for Kinesiophobia (TSK)-11, and pain catastrophizing, evaluated by the Pain Catastrophizing Scale (PCS), were associated with quality of life (QOL) in patients with hip OA. Methods This cross-sectional study was conducted between November 2017 and December 2018. Ninety-one consecutively enrolled patients with severe hip OA were scheduled for primary unilateral total hip arthroplasty. The EuroQOL-5 Dimensions questionnaire was used to measure general QOL. The Japanese Orthopedic Association Hip Disease Evaluation Questionnaire was used to assess disease-specific QOL. The covariates included age, sex, body mass index (BMI), pain intensity, high pain catastrophizing (PCS ≥ 30), and high kinesiophobia (TSK-11 ≥ 25). Variables were subjected to multivariate analysis using each QOL scale. Results In multiple regression analysis, pain intensity, high pain catastrophizing, and BMI were independently correlated with the disease-specific QOL scale. High pain catastrophizing, pain intensity, and high kinesiophobia were independently correlated with the general QOL scale. Conclusions High pain catastrophizing (PCS ≥ 30) was independently associated with disease and general QOL scales. High kinesiophobia (TSK-11 ≥ 25) was independently associated with the general QOL scale in preoperative patients with severe hip OA.

Abstract The molecular pathophysiology underlying lumbar spondylosis development remains unclear. To identify genetic factors associated with lumbar spondylosis, we conducted a genome-wide association study using 83 severe lumbar spondylosis cases and 182 healthy controls and identified 65 candidate disease-associated single nucleotide polymorphisms (SNPs). Replication analysis in 510 case and 911 control subjects from five independent Japanese cohorts identified rs2054564, located in intron 7 of ADAMTS17, as a disease-associated SNP with a genome-wide significance threshold (P = 1.17 × 10–11, odds ratio = 1.92). This association was significant even after adjustment of age, sex, and body mass index (P = 7.52 × 10–11). A replication study in a Korean cohort, including 123 case and 319 control subjects, also verified the significant association of this SNP with severe lumbar spondylosis. Immunohistochemistry revealed that fibrillin-1 (FBN1) and ADAMTS17 were co-expressed in the annulus fibrosus of intervertebral discs (IVDs). ADAMTS17 overexpression in MG63 cells promoted extracellular microfibrils biogenesis, suggesting the potential role of ADAMTS17 in IVD function through interaction with fibrillin fibers. Finally, we provided evidence of FBN1 involvement in IVD function by showing that lumbar IVDs in patients with Marfan syndrome, caused by heterozygous FBN1 gene mutation, were significantly more degenerated. We identified a common SNP variant, located in ADAMTS17, associated with susceptibility to lumbar spondylosis and demonstrated the potential role of the ADAMTS17-fibrillin network in IVDs in lumbar spondylosis development.

Abstract Background To date, no interventional trial has assessed the efficacy and safety of vonoprazan and high‐dose (500 mg four times daily, 2000 mg/day) amoxicillin dual therapy in terms of Helicobacter pylori eradication. We explored whether this was an appropriate first‐line treatment. Methods This prospective, dual‐center, single‐arm interventional study was performed in Japan. Twenty H. pylori‐positive patients lacking any eradication history were treated with vonoprazan 20 mg twice daily and amoxicillin 500 mg four times daily (qid) for 7 days. Eradication was evaluated using a stool H. pylori antigen test. We evaluated safety using patient questionnaires. This study was registered in the jRCT database (jRCT031200128). Results The intention‐to‐treat and per‐protocol eradication rates were 90% (95% confidence interval [CI] 68.3–98.8%, n = 20) and 94.4% (95% CI 72.7–99.9%, n = 18) respectively. No significant adverse event was recorded. Conclusion Vonoprazan/high‐dose amoxicillin dual therapy can be a safe standard first‐line therapy. We are now undergoing a randomized controlled trial comparing dual therapy and vonoprazan‐based triple therapy.

Introduction: Long fusion surgery for adult spinal deformity may restrict activities of daily living due to lumbar stiffness. While the Lumbar Stiffness Disability Index (LSDI) can help assess lumbar stiffness, in Asia the external validity of this questionnaire has not been sufficiently examined. We performed the psychometric evaluation and external validation of the Japanese version of the LSDI (LSDI-J). Methods: Fifty consecutive patients (14 males and 36 females; mean age 70.6 years) who underwent lumbar fusion surgery at our institution a minimum of one year after surgery and who visited the outpatient clinic between April and May 2019, were surveyed using the LSDI-J. The mean number of fusion levels was 4.4. Cronbach's alpha coefficients were calculated for internal consistency, and the intraclass correlation coefficient (ICC) was calculated to evaluate reliability. External validity was assessed by comparisons with the Oswestry Disability Index (ODI), the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), and the lumbar range of motion (LROM) with LSDI-J scores. Results: Cronbach's alpha coefficient was 0.652 overall, and 0.849 after excluding Question 10 due to a low response rate. The ICC was 0.824 overall and 0.851 after excluding Question 10. The correlation with the ODI was 0.684, and the correlation coefficients with each domain of the JOABPEQ ranged from −0.590 to −0.413, indicating moderate correlation. However, LROM and the LSDI-J were not correlated (r=−0.055, P=0.734). Conclusions: The LSDI-J may not be suitable in Japan because there was no correlation with LROM, the most important factor for external validity. It may be necessary to investigate why the LSDI-J did not apply to the Japanese population in terms of lower limb function. Alternatively, a unique method may be needed to assess lumbar stiffness disability that is more suitable for actual clinical practice in Japan.

Introduction: Adult spinal fusion surgery improves lumbar alignment and patient satisfaction. Adult spinal deformity surgery improves saggital balance not only lumbar lesion, but also at hip joint coverage. It was expected that hip joint coverage rate was improved and joint stress decreased. However, it was reported that adjacent joint disease at hip joint was induced by adult spinal fusion surgery including sacroiliac joint fixation on an X-ray study. The mechanism is still unclear. We aimed to investigate the association between lumbosacral fusion including sacroiliac joint fixation and contact stress of the hip joint. Methods: A 40-year-old woman with intact lumbar vertebrae underwent computed tomography. A three-dimensional nonlinear finite element model was constructed from the L4 vertebra to the femoral bone with triangular shell elements (thickness, 2 mm; size, 3 mm) for the cortical bone's outer surface and 2-mm (lumbar spine) or 3-mm (femoral bone) tetrahedral solid elements for the remaining bone. We constructed the following four models: a non-fusion model (NF), a L4-5 fusion model (L5F), a L4-S1 fusion model (S1F), and a L4-S2 alar iliac screw fixation model (S2F). A compressive load of 400 N was applied vertically to the L4 vertebra and a 10-Nm bending moment was additionally applied to the L4 vertebra to stimulate flexion, extension, left lateral bending, and axial rotation. Each model's hip joint's von Mises stress and angular motion were analyzed. Results: The hip joint's angular motion in NF, L5F, S1F, and S2F gradually increased; the S2F model presented the greatest angular motion. Conclusions: The average and maximum contact stress of the hip joint was the highest in the S2F model. Thus, lumbosacral fusion surgery with sacroiliac joint fixation placed added stress on the hip joint. We propose that this was a consequence of adjacent joint spinopelvic fixation. Lumbar-to-pelvic fixation increases the angular motion and stress at the hip joint.

Abstract The relationship between acetabular dysplasia and spino-pelvic alignment remains unclear. The aim of this study was to clarify the association between acetabular dysplasia and spino-pelvic alignment, based on a large-scale population-based cohort in Japan. From the third survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study, 1,481 participants (491 men and 990 women; mean age, 65.3 years) were analyzed. Center-edge (CE) angle and spino-pelvic parameters (lumbar lordosis, LL; sacral slope, SS; pelvic tilt, PT; pelvic incidence, PI) were measured radiographically. Acetabular dysplasia was defined as a CE angle

Abstract Background Airway complications are the most serious complications after anterior cervical decompression and fusion (ACDF) and can have devastating consequences if their detection and intervention are delayed. Plain radiography is useful for predicting the risk of dyspnea by permitting the comparison of the prevertebral soft tissue (PST) thickness before and after surgery. However, it entails frequent radiation exposure and is inconvenient. Therefore, we aimed to overcome these problems by using ultrasonography to evaluate the PST and upper airway after ACDF and investigate the compatibility between X-ray and ultrasonography for PST evaluation. Methods We included 11 radiculopathy/myelopathy patients who underwent ACDF involving C5/6, C6/7, or both segments. The condition of the PST and upper airway was evaluated over 14 days. The Bland–Altman method was used to evaluate the degree of agreement between the PST values obtained using radiography versus ultrasonography. The Pearson correlation coefficient was used to determine the relationship between the PST measurement methods. Single-level and double-level ACDF were performed in 8 and 3 cases, respectively. Results PST and upper airway thickness peaked on postoperative day 3, with no airway complications. The Bland–Altman bias was within the prespecified clinically nonsignificant range: 0.13 ± 0.36 mm (95% confidence interval 0.04–0.22 mm). Ultrasonography effectively captured post-ACDF changes in the PST and upper airway thickness and detected airway edema. Conclusions Ultrasonography can help in the continuous assessment of the PST and the upper airway as it is simple and has no risk of radiation exposure risk. Therefore, ultrasonography is more clinically useful to evaluate the PST than radiography from the viewpoint of invasiveness and convenience.

Introduction: Osteoporotic vertebral compression fracture (OVCF) in the elderly is a major public health concern. This retrospective case-control study aimed to determine the difference in interobserver reliability between radiography, magnetic resonance imaging (MRI), and computed tomography (CT), respectively, and whether CT radiological findings can predict prolonged back pain at 2 weeks after OVCFs. Methods: Patients were divided into the prolonged back pain group or the recovered back pain group depending on the numerical rating scale at 2 weeks after admission. Radiography, MRI, and CT images were classified on the basis of conventions described by previous classifications. Interobserver reliability was calculated on images rated by two board-certified spine surgeons. Multivariate logistic regression models were used to evaluate whether the presence or absence of anterior wall injury, endplate deficit, posterior wall injury, lateral wall injury, or intervertebral disc deficit on CT was predictive of prolonged back pain. Results: Of the 130 patients, 89 cases (68.5%) involved prolonged back pain at 2 weeks after admission. Neither average age (79.8 vs. 80.1 years, respectively) nor duration to initial consultation (9.4 vs. 6.4 days, respectively) differed significantly between the prolonged and recovered back pain groups. Interobserver reliability was 0.51, 0.77 (0.67-0.86), and 0.82 (0.72-0.92) for radiography, MRI, and CT, respectively. After adjusting for confounding factors such as age, sex, duration to initial consultation, and extent of OVCF, the multivariate analysis showed that the presence of endplate deficit and posterior wall injury was a significant predictive factor for prolonged back pain (odds ratio [OR] 8.5, area under the curve (AUC); 0.79 and OR 2.5, AUC 0.72), respectively. Conclusions: Good reliability assessments of CT-based evaluations were noted. After a detailed novel CT evaluation at initial presentation, the presence of an endplate deficit and posterior wall injury was the significant risk factor for prolonged back pain at 2 weeks after an OVCF.

Abstract Background There has been a paucity of literature revealing the discrepancy between self-recognition about hallux valgus (HV) and radiographically-evaluated foot configuration. Knowing this discrepancy will help to make a comparative review of the findings of previous literatures about epidemiological studies about the prevalence of HV. Questions/purposes (1) Is there a discrepancy between radiographically-assessed and self-recognized HV in the general population? (2) What factors affect the self-recognition of HV in the general population? Methods The fifth survey of the Research on Osteoarthritis/Osteoporosis against Disability study involved 1996 participants who had undergone anterior-posterior radiography of bilateral feet and answered a simple dichotomous questionnaire on self-recognition of HV. Measurements of the HV angle (HVA), interphalangeal angle of the hallux (IPA), and intermetatarsal angle between 1st and 2nd metatarsals (IMA) were performed using radiographs. Radiographic diagnosis of HV was done using the definition of hallux valgus angle of 20° or more. After univariate comparison of the participant backgrounds and radiographic measurements between participants with or without self-recognition of HV, multivariable logistic regression analysis was conducted in order to reveal independent factors affecting self-recognition. Results Significant difference was found between the prevalence of radiographically-assessed and self-recognized HV (29.8% vs. 16.5%, p

Abstract Background Posterior pedicle screw fixation without fusion has been commonly applied for thoracolumbar burst fracture. Implant removal is performed secondarily after bone union. However, the occurrence of secondary kyphosis has recently attracted attention. Secondary kyphosis results in poor clinical outcomes. The purpose of this was to determine predictors of kyphosis after implant removal following posterior pedicle screw fixation without fusion for thoracolumbar burst fracture. Methods This retrospective study reviewed 59 consecutive patients with thoracolumbar burst fracture who underwent implant removal following posterior pedicle screw fixation without fusion. Inclusion criteria were non-osteoporotic fracture and T11-L3 burst fracture. Old age, sex, initial severe wedge deformity, initial severe kyphosis, and vacuum phenomenon were examined as factors potentially associated with final kyphotic deformity (defined as kyphotic angle greater than 25°) or loss of correction. Logistic regression analysis was performed using propensity score matching. Results Among the 31 female and 28 male patients (mean age 38 years), final kyphotic deformity was found in 17 cases (29%). Multivariate analysis showed a significant association with the vacuum phenomenon. Loss of correction was found in 35 cases (59%) and showed a significant association with the vacuum phenomenon. There were no significant associations with other factors. Conclusions The findings of this study suggest that the vacuum phenomenon before implant removal may be a predictor of secondary kyphosis of greater than 25° after implant removal following posterior pedicle screw fixation without fusion for thoracolumbar burst fracture, but that old age, sex, initial severe kyphosis, and initial severe wedge deformity may not be predictors.

Abstract Studies have suggested a relationship between sagittal spinal malalignment and low back pain (LBP). The current study investigated the relationship of spinal alignment with LBP and physical performance in 1491 individuals who attended the second follow-up visit of the Wakayama Spine Study. The sagittal vertical axis at C7 (C7 SVA) was measured by a spine surgeon. The occurrence of LBP within one month, pain intensity, Oswestry Disability Index (ODI), and physical performance (grip strength, 6-m walking time, chair stand test, one-leg standing test) were also evaluated. LBP in the previous month was determined using ODI, and indicators of physical performance were measured. The mean C7 SVA was 11.0 ± 42.7 mm and was significantly greater in older participants (p

Objective: The trends in prevalence of hip osteoarthritis (OA) over a 10-year period among Japanese men and women were investigated using the data from the Research on Osteoarthritis/osteoporosis Against Disability study. Design: We analyzed the data of 2924 baseline survey participants (1026 men, 1898 women) aged 40–89 years (mean 70.7 years) residing in urban, mountainous, and coastal communities who were surveyed in 2005–2007. We compared these data with that of 2347 participants (726 men, 1621 women) aged 40–89 years (mean 69.2 years) from the fourth survey in 2015–2016. The fourth survey invited participants to attend follow-ups for baseline survey and recruited new participants. After scoring the radiographs using the Kellgren/Lawrence (K/L) grading system, hip OA was defined as a K/L score ≥2. Results: The prevalence of radiographic hip OA was 18.4% and 14.4% in the baseline survey, and 16.0% and 10.7% in the fourth survey among men and women, respectively. Among the participants aged 40–69 years, the prevalence of radiographic hip OA was significantly lower during the fourth survey than during the baseline survey. Whereas, among elderly men aged 70–79 years, radiographic hip OA was significantly less prevalent during the baseline survey than during the fourth survey. From the logistic regression analysis results, radiographic hip OA was significantly less prevalent during the fourth survey than during the baseline survey (odds ratio: 0.55, 95% confidence interval: 0.46–0.65). Conclusion: At a 10-year interval, the prevalence of radiographic hip OA shows an improving trend.

BackgroundArtificial intelligence–assisted interactive health promotion systems are useful tools for the management of musculoskeletal conditions. ObjectiveThis study aimed to explore the effects of web-based video patient education and strengthening exercise therapy, using a mobile messaging app, on work productivity and pain in patients with chronic low back pain (CLBP) receiving pharmacological treatment. MethodsPatients with CLBP were randomly allocated to either the exercise group, who received education and exercise therapy using a mobile messaging app, or the conventional group. For patient education, a web-based video program was used to provide evidence-based thinking regarding the importance of a cognitive behavioral approach for CLBP. The exercise therapy was developed in accordance with the recommendations for alignment, core muscles, and endogenous activation, including improvement of posture and mobility for proper alignment, stimulation and/or strengthening of deep muscles for spinal stability, and operation of intrinsic pain for the activation of endogenous substances by aerobic exercise. Both groups continued to receive the usual medical care with pharmacological treatment. The end points were changes in work productivity, pain intensity, quality of life, fear of movement, and depression. The observation period for this study was 12 weeks. An analysis adjusted for baseline values, age at the time of consent acquisition, sex, and willingness to strengthen the exercise therapy was performed. ResultsThe exercise and conventional groups included 48 and 51 patients, with a mean age of 47.9 years (SD 10.2 years; n=27, 56.3% male patients) and 46.9 years (SD 12.3 years; n=28, 54.9% male patients) in the full analysis set, respectively. No significant impact of these interventions on work productivity was observed in the exercise group compared with the conventional group (primary end point: Quantity and Quality method; 0.062 vs 0.114; difference between groups −0.053, 95% CI −0.184 to 0.079; P=.43). However, the exercise group showed consistently better trends for the other end points than did the conventional group. Compared with the conventional group, the exercise group showed a significant improvement in the symptoms of low back pain (3.2 vs 3.8; difference between groups −0.5, 95% CI −1.1 to 0.0; P=.04), quality of life (EuroQoL 5 Dimensions 5 Level: 0.068 vs 0.006; difference between groups 0.061, 95% CI 0.008 to 0.114; P=.03), and fear of movement at week 12 (−2.3 vs 0.5; difference between groups −2.8, 95% CI −5.5 to −0.1; P=.04). ConclusionsThis study suggests that patient education and strengthening exercise therapy using a mobile messaging app may be useful for treating CLBP. This study does not reveal the effect of therapeutic interventions on CLBP on work productivity. Thus, further research is required to assess work productivity with therapeutic interventions. Trial RegistrationUniversity Hospital Medical Information Network Clinical Trials Registry UMIN000041037; https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000046866

Abstract To evaluate the characteristics of the spinopelvic parameters on radiography in patients with sacroiliac joint pain (SIJP). Two hundred fifty patients were included and divided into the SIJP group (those diagnosed with SIJP based on physical findings and response to analgesic periarticular injections; n = 53) and the non-SIJP group (those with low back pain [LBP] because of other reasons; n = 197). We compared their demographic characteristics and spinopelvic parameters using radiography. All differences found in the patients’ demographic characteristics and spinopelvic parameters were analyzed. More female participants experienced SIJP than male participants (P = 0.0179). Univariate analyses revealed significant differences in pelvic incidence (PI) (P = 0.0122), sacral slope (SS) (P = 0.0034), and lumbar lordosis (LL) (P = 0.0078) between the groups. The detection powers for PI, SS, and LL were 0.71, 0.84, and 0.66, respectively. Logistic regression analyses, after adjustment for age and sex, revealed significant differences in PI (P = 0.0308) and SS (P = 0.0153) between the groups, with odds ratios of 1.03 and 1.05, respectively. More female participants experienced SIJP than male participants. Higher PI and SS values were related to SIJP among LBP patients.

Abstract Pistol grip deformity (PGD) may be the main factor in femoroacetabular impingement development. This study aimed to clarify the epidemiological indices and factors related to PGD in Japanese people. This population-based cohort study included 1575 local Japanese residents. PGD, center edge angle, and joint space width were measured radiographically. We investigated the relationship between PGD and spino-pelvic parameters. Factors associated with PGD were examined using multiple logistic regression analysis, with the presence/absence of PGD as an objective variable, and sex, age, body mass index (BMI), and the presence/absence of hip pain or spino-pelvic parameters as explanatory variables. In the entire cohort, 4.9% (10.6% men, 2.1% women) had PGD on at least one side. A trend was observed between PGD and increasing age in both men and women (men: p

In this study, we examined machine extraction of polymer data from tables in scientific articles. The extraction system consists of five processes: table extraction, data formatting, polymer name recognition, property specifier identification, and data extraction. Tables were first extracted in plain text. XML versions of scientific articles were used, and the tabular forms were accurately extracted, even for complicated tables, such as multi-column, multi-row, and merged tables. Polymer name recognition was performed using a named entity recognizer created by deep neural network learning of polymer names. The preparation cost of the training data was reduced using a rule-based algorithm. The target polymer properties in this study were glass transition temperature (Tg), melting temperature (Tm), and decomposition temperature (Td), and the specifiers were identified using partial string matching. Through these five processes, 2,181 data points for Tg, 1,526 for Tm, and 2,316 for Td were extracted from approximately 18,000 scientific articles published by Elsevier. Nearly half of them were extracted from complicated tables. The F-scores for the extraction were 0.871, 0.870, and 0.841, respectively. These results indicate that the extraction system created in this study can rapidly and accurately collect large amounts of polymer data from tables in scientific literature.

BackgroundSurgery for intertrochanteric fractures using intramedullary hip nails (IHNs) is among the most common surgical procedures in the orthopedic field. Although IHNs provide good overall outcomes, they sometimes cause complications, such as loss of reduction and cut-out. Here, we investigated the usefulness of IHNs with an anterior offset (Best Fit Nail® [BFN]) in maintaining fragment reduction and ensuring proper lag screw position compared with conventional non-offset nails (Proximal Femoral Nail Antirotation® [PFNA]), using postoperative computed tomography (CT).MethodsFifty consecutive patients with intertrochanteric fractures who underwent surgery with BFNs (BFN group) and 50 patients who underwent surgery with PFNAs (PFNA group) were retrospectively analyzed. Indices evaluated by postoperative CT were displacement distance of proximal fragment relative to distal fragment, reduction status (intramedullary, anatomical, and extramedullary types), lag screw direction, and angle between lag screw and femoral neck axis (deviation angle).ResultsMedian [interquartile range] displacement distance was significantly smaller in the BFN group (0 [0, 0] mm) compared with the PFNA group (5.2 [3.6, 7.1] mm) (pConclusionsIntertrochanteric fracture surgery using offset BFNs exhibited significantly smaller displacement distance, better reduction status, and higher frequency of no deviation with central lag screw position, compared with surgery using non-offset PFNAs.

Objectives This prospective study aimed to determine the association between radiographic lumbar spinal stenosis (LSS) and the quality of life (QOL) in the general Japanese population. Methods The severity of radiographic LSS was qualitatively graded on axial magnetic resonance images as follows: no stenosis, mild stenosis with ≤1/3 narrowing, moderate stenosis with a narrowing between 1/3 and 2/3, and severe stenosis with > 2/3 narrowing. Patients less than 40 years of age and those who had undergone previous lumbar spine surgery were excluded from the study. The Oswestry Disability Index (ODI), which includes 10 sections, was used to assess the QOL. One-way analysis of variance was performed to determine the statistical relationship between radiographic LSS and ODI. Further, logistic regression analysis adjusted for gender, age, and body mass index was performed to detect the relationship. Results Complete data were available for 907 patients (300 men and 607 women; mean age, 67.3±12.4 years). The prevalence of severe, moderate, and non-mild/non-radiographic were 30%, 48%, and 22%, respectively. In addition, the mean values of ODI in each group were 12.9%, 13.1%, and 11.7%, respectively, and there was no statistically significant difference between the three groups in logistic analysis (P = 0.55). In addition, no significant differences in any section of the ODI were observed among the groups. However, severe radiographic LSS was associated with low back pain in the "severe" group as determined by logistic analysis adjusted for gender, age, and body mass index (odds ratio: 1.53, confidence interval: 1.13–2.07) compared with the non-severe group. Conclusion In this general population study, severe radiographic LSS was associated with low back pain (LBP), but did not affect ODI.

A recent trend in Japan is the increasing number of older patients with diabetes. Treatment for diabetes mellitus in older patients involves a wide variety of strategies, not only for better glycemic control, but also for the prevention and improvement of locomotive syndrome, sarcopenia, and frailty. Previous studies have shown that tele-guidance treatment interventions are effective for weight loss and increase in physical activity, but their effects on locomotive syndrome, sarcopenia, and glycemic control have not been examined. The objective of this study is to assess the efficacy of tele-guidance for intensive therapeutic interventions for diabetes mellitus in older patients, carried out by a qualified physical therapist with diabetes-specific qualifications and knowledge. This multi-center study, including 6 hospitals in Japan, is a prospective, parallel-group, single-blinded, randomized controlled trial. A total of 78 patients will be registered based on our preliminary studies. Patients aged 65–89 years with type 2 diabetes mellitus will be assigned randomly to intensive intervention and control groups. The effectiveness of 6 months of intervention will be verified by a physical therapist. The primary outcome measure will be the change in isometric knee extension force (KEF), whereas the secondary outcomes will be changes in skeletal muscle mass, motor function, glycemic control, and satisfaction with the treatment. When prescribing exercise therapy to older patients with diabetes mellitus, the various risks associated with exercise should be taken into consideration. Therefore, this study has been designed to establish the efficacy of intensive physiotherapy programs in older patients with diabetes mellitus. Provided that this study shows the effectiveness of tele-guidance in improving physical function and glycemic control, it can be a new intervention strategy for exercise therapy in older diabetes patients.

Abstract Background MRI scanning has revolutionized the clinical diagnosis of lumbar spinal stenosis (LSS). However, there is currently no consensus as to how best to classify MRI findings which has hampered the development of robust longitudinal epidemiological studies of the condition. We developed and tested an automated system for grading lumbar spine MRI scans for central LSS for use in epidemiological research. Methods Using MRI scans from the large population-based cohort study (the Wakayama Spine Study), all graded by a spinal surgeon, we trained an automated system to grade central LSS in four gradings of the bone and soft tissue margins: none, mild, moderate, severe. Subsequently, we tested the automated grading against the independent readings of our observer in a test set to investigate reliability and agreement. Results Complete axial views were available for 4855 lumbar intervertebral levels from 971 participants. The machine used 4365 axial views to learn (training set) and graded the remaining 490 axial views (testing set). The agreement rate for gradings was 65.7% (322/490) and the reliability (Lin’s correlation coefficient) was 0.73. In 2.2% of scans (11/490) there was a difference in classification of 2 and in only 0.2% (1/490) was there a difference of 3. When classified into 2 groups as ‘severe’ vs ‘no/mild/moderate’. The agreement rate was 94.1% (461/490) with a kappa of 0.75. Conclusions This study showed that an automated system can “learn” to grade central LSS with excellent performance against the reference standard. Thus SpineNet offers potential to grade LSS in large-scale epidemiological studies involving a high volume of MRI spine data with a high level of consistency and objectivity.

Abstract Background High prevalence of low back pain (LBP) in nurses has been reported globally. Ergonomic factors and work-related psychosocial factors have been focused on as risk factors. However, evidence on the role of fear-avoidance beliefs (FABs) concerning LBP in nurses is lacking. This study examined LBP prevalence and the association between FABs and chronic disabling LBP that interfered with work and lasted ≥ 3 months. Methods Female nurses (N = 3066; mean age = 35.8 ± 10.6 years) from 12 hospitals in Japan participated. A self-reported questionnaire was used to collect information on sociodemographics, LBP, work-related factors, and psychological distress. FABs about physical activity were assessed using a subscale from the FAB Questionnaire (score range = 0–24). The participants were asked to choose one of four statements regarding their LBP in the past 4 weeks: 1) I did not have LBP, 2) I had LBP without work difficulty, 3) I had LBP with work difficulty but without requiring absence from work, and 4) I had LBP requiring absence from work. If the participant had LBP in the past 4 weeks, it was also inquired if the LBP had lasted for ≥ 3 months. Chronic disabling LBP was defined as experiencing LBP with work difficulty in the past 4 weeks which had lasted for ≥ 3 months. In the nurses who had experienced any LBP in the past 4 weeks, we examined the association between FABs and experiencing chronic disabling LBP using multiple logistic regression models adjusting for pain intensity, age, body mass index, smoking status, psychological distress, hospital department, weekly work hours, night shift work, and the12 hospitals where the participants worked. Results Four-week and one-year LBP prevalence were 58.7 and 75.9%, respectively. High FABs (≥ 15) were associated with chronic disabling LBP (adjusted odds ratio = 1.76, 95% confidence interval [1.21–2.57], p = 0.003). Conclusions LBP is common among nurses in Japan. FABs about physical activity might be a potential target for LBP management in nurses. Trial registration UMIN-CTR UMIN000018087. Registered: June 25, 2015.

Abstract Background Antimicrobial prophylaxis (AMP) is one of the most important measures for preventing surgical site infections (SSIs); however, controversies remain regarding its adequate duration. Although the World Health Organization and the Center for Disease Control and Prevention do not recommend additional AMP after closure, the American Society of Health-System Pharmacists and the Musculoskeletal Infection Society permit the use of postoperative AMP, but recommend discontinuation within 24 h. Similarly, the Japanese Society of Chemotherapy and the Japan Society for Surgical Infection also permit AMP within 24–48 h after various orthopaedic procedures. In these guidelines, recommendations regarding AMP duration were weak due to a relative lack of evidence, and currently, there is no high-quality evidence comparing AMP use within 24 h versus 24–48 h regarding orthopaedic procedures. Urinary tract infection (UTI) and respiratory tract infection (RTI) are also important health care-associated infections (HAIs) faced after surgery. Although AMP duration may affect these HAIs, its effects have not been well evaluated. Methods We have organized a multicenter, prospective, cluster pseudo-randomized controlled trial to examine the non-inferiority of shorter AMP duration (within 24 h) against longer duration (24–48 h) in preventing postoperative HAIs. Participating facilities will be divided into two groups. In Group 24, AMP will be discontinued within 24 h after surgery. In Group 48, AMP will be discontinued within 24–48 h after surgery. The group allocation will be switched every 2 months until the targeted recruitment (500 participants per group) is met. The primary outcome will be the cumulative incidence of all HAIs (SSI, UTI, RTI, and other infectious diseases), which require antibiotic therapies within 30 days after surgery. In addition to mortality and cardiovascular events, prolonged hospitalization (> 30 days) and the rate of antibiotic resistance rate of SSI pathogens will also be evaluated. Outcomes will be evaluated within 30–180 days after surgery in person by the surgeon, by mail, or by telephone survey. Data will be analyzed by a statistician not engaged in data collection. Discussion This study may provide valuable information for developing future recommendations for adequate AMP duration after clean orthopaedic surgery. Trial registration UMIN000030929, registered January 22, 2018.

Introduction: Chronic low back pain (CLBP), defined as low back pain persisting for at least 3 months, leads to limitations in the activities of daily living and decreased quality of life. Individualized self-exercise education could be a preferable treatment option, especially in community-dwelling people with CLBP. Previous studies, however, did not directly compare the effects of therapist-led self-exercise education and material-only education, and there are only a few studies investigating the effects of low-dose (comprising a few sessions) self-exercise education on CLBP. We present a protocol of community-based, randomized study to evaluate the effects of low-dose (comprising a few sessions), therapist-led self-exercise education on CLBP. Methods: Forty-eight participants with CLBP (men and women, aged 40-74 years) will be allocated to therapeutic self-exercise education programs, either a therapist-led group (2-week therapist's consultation and material use) or material-only group (material use only), in a randomized controlled trial. Pain intensity (NRS, numeric rating scale), pain disability (RDQ, Roland-Morris disability questionnaire), pain self-efficacy (PSEQ, pain self-efficacy questionnaire), and quality of life score (EQ-5D, European quality of life-5 dimensions) will be measured at baseline and at 4, 12, and 24 weeks. We will apply a repeated-measures design with mixed-effect models to estimate group differences from the baseline. Ethics/Trial registration number: The protocol was approved by the Ethics Committees of the Osaka Center for Cancer and Cardiovascular Disease Prevention and Osaka University. The trial registration number is registered on the University Hospital Medical Information Network (UMIN000024537).

BackgroundMusculoskeletal symptoms such as neck and shoulder pain/stiffness and low back pain are common health problems in the working population. They are the leading causes of presenteeism (employees being physically present at work but unable to be fully engaged). Recently, digital interventions have begun to be used to manage health but their effectiveness has not yet been fully verified, and adherence to such programs is always a problem. ObjectiveThis study aimed to evaluate the improvements in musculoskeletal symptoms in workers with neck/shoulder stiffness/pain and low back pain after the use of an exercise-based artificial intelligence (AI)–assisted interactive health promotion system that operates through a mobile messaging app (the AI-assisted health program). We expected that this program would support participants’ adherence to exercises. MethodsWe conducted a two-armed, randomized, controlled, and unblinded trial in workers with either neck/shoulder stiffness/pain or low back pain or both. We recruited participants with these symptoms through email notifications. The intervention group received the AI-assisted health program, in which the chatbot sent messages to users with the exercise instructions at a fixed time every day through the smartphone’s chatting app (LINE) for 12 weeks. The program was fully automated. The control group continued with their usual care routines. We assessed the subjective severity of the neck and shoulder pain/stiffness and low back pain of the participants by using a scoring scale of 1 to 5 for both the intervention group and the control group at baseline and after 12 weeks of intervention by using a web-based form. We used a logistic regression model to calculate the odds ratios (ORs) of the intervention group to achieve to reduce pain scores with those of the control group, and the ORs of the subjective assessment of the improvement of the symptoms compared to the intervention and control groups, which were performed using Stata software (version 16, StataCorp LLC). ResultsWe analyzed 48 participants in the intervention group and 46 participants in the control group. The adherence rate was 92% (44/48) during the intervention. The participants in the intervention group showed significant improvements in the severity of the neck/shoulder pain/stiffness and low back pain compared to those in the control group (OR 6.36, 95% CI 2.57-15.73; P

Abstract Background The aim of this study was to investigate the correlation between radiographic measurement in lumbar spine and clinical information including symptoms or results of functional testing using a baseline data of longitudinal cohort study. Methods A total of 314 elderly subjects were recruited from 5 orthopedic clinics or affiliated facilities. Data for the present investigation were collected via an interviewer-administered questionnaire, which included questions on past medical history, drug history, pain area. And also results of functional testing and X-ray imaging of the lumbar spine were collected. Analysis was carried out to determine any correlation between results of X-ray imaging of the lumbar spine and other collected data, and sorted regarding Akaike Information Criterion (AIC). The correlations among these variables and odds ratio were also analyzed. Results T12/L1% disc height showed a minimum AIC value with buttock pain (− 4.57) and history of vertebral fracture (− 4.05). The L1/L2, L2/L3, and L3/L4% disc height had a minimal AIC value with knee pain (− 4.11, − 13.3, − 3.15, respectively), and odds ratio of knee pain were 3.5, 3.8, and 2.7, respectively. Conclusions Correlation was recognized between the T12/L1% disc height and both buttock pain and previous vertebral fractures, and the L1/L2, L2/L3, and L3/L4% disc height showed a correlation with knee pain. Especially the L2/L3% disc height and knee pain had a strong correlation. It was suggested that these findings may provide additional basis to the concept that lumbar spinal lesion associates with knee pain clinically.

Abstract Background Schwannomas are well-encapsulated, benign neoplasms, and enucleation is a standard operation procedure. The incidence of neurological complications after surgical treatment for schwannomas of the extremities varies, and there is no consensus concerning predictive factors for complications. The aim of this study was to elucidate predictive factors for complications after surgical treatment of schwannomas that develop in the major nerves of the extremities. Methods A total of 139 patients with 141 schwannomas arising in major nerves were retrospectively analyzed. Data regarding preoperative clinical features, the postoperative neurological complications, and clinical course of complications, with a median follow-up period of 2 months (range, 0.5–96), were obtained. Predictive factors for complications were statistically analyzed. Results Postoperative complications occurred in 49 lesions (34.8%), including 42 with sensory disturbance and 8 with motor weakness. In univariate analysis, older age, tumors originating from the upper extremity, and major motor nerve involvement were associated with a higher complication rate (p = 0.03, p = 0.003, and p = 0.001, respectively). In multivariate analysis, major motor nerve involvement was an independent predictive factor for postoperative complications (p = 0.03). Almost all complications gradually improved, but 6 out of 8 patients with motor weakness did not show full recovery at the final follow-up. Conclusions Schwannomas originating from major motor nerves can lead to a higher risk for postoperative complications.

Introduction: We previously reported that transplantation of hepatic cell sheets from human bone marrow-derived mesenchymal stem cells (BM-MSCs) with hexachlorophene, a Wnt/β-catenin signaling inhibitor, ameliorated acute liver injury. In a further previous report, we identified IC-2, a newly synthesized derivative of the Wnt/β-catenin signaling inhibitor ICG-001, as a potent inducer of hepatic differentiation of BM-MSCs. Methods: We manufactured hepatic cell sheets by engineering from human BM-MSCs using the single small molecule IC-2. The therapeutic potential of IC-2-induced hepatic cell sheets was assessed by transplantation of IC-2- and hexachlorophene-treated hepatic cell sheets using a mouse model of acute liver injury. Results: Significant improvement of liver injury was elicited by the IC-2-treated hepatic cell sheets. The expression of complement C3 was enhanced by IC-2, followed by prominent hepatocyte proliferation stimulated through the activation of NF-κB and its downstream molecule STAT-3. Indeed, IC-2 also enhanced the expression of amphiregulin, resulting in the activation of the EGFR pathway and further stimulation of hepatocyte proliferation. As another important therapeutic mechanism, we revealed prominent reduction of oxidative stress mediated through upregulation of the thioredoxin (TRX) system by IC-2-treated hepatic cell sheets. The effects mediated by IC-2-treated sheets were superior compared with those mediated by hexachlorophene-treated sheets. Conclusion: The single compound IC-2 induced hepatic cell sheets that possess potent regeneration capacity and ameliorate acute liver injury. Keywords: Hepatic cell sheets, Mesenchymal stem cells, Liver regeneration, Wnt/β-catenin signal inhibitor, Acute liver failure

Abstract Background The patient-rated Core Outcome Measures Index (COMI) assesses the multidimensional impact of back problems on the sufferer. The brevity and comprehensibility of the tool make it practical for use in clinical and research settings. Although the COMI has been cross-culturally adapted in various languages worldwide, there is currently no Japanese version. The aim of this study was to develop a Japanese version of the COMI by: (1) performing a cross-cultural adaptation of the English version and (2) evaluating the psychometric properties of the Japanese version of the COMI in Japanese volunteers with chronic back problems. Methods The English version of the COMI was cross-culturally adapted for the Japanese language using established guidelines. The pre-final version was pilot-tested in five Japanese-speaking patients with low back pain (LBP) and a history of spine surgery. The psychometric properties of the Japanese COMI were tested in a group of 1052 individuals with chronic LBP (LBP ≥3 months), aged 20–69 years, who were recruited through a web-based survey. The psychometric properties that were evaluated included convergent and known-group validity, using the following reference questionnaires: EuroQol 5 Dimension, Roland Morris Disability Questionnaire, Short Form 8™ Health Survey, and the Keele STarT Back Screening Tool. Results The pre-final version of the cross-culturally adapted Japanese COMI was completed without any major problems of understanding or acceptability. For the evaluation of its psychometric properties, tests for convergent validity showed moderate correlations between COMI items and the respective reference questionnaires for symptom-specific well-being [− 0.33–−0.48] and disability domains [0.48] and strong correlations (> 0.5) for the other domains and the COMI summary score. The analysis of known-group validity showed a linear trend for the COMI score in relation to prognostic risk (P

Abstract Background Microendoscopic foraminotomy has been reported to be effective for the treatment of cervical radiculopathy, using outcome measurement scores such as the neck disability index (NDI) and numerical rating scale (NRS). However, the scores for spine surgery do not always reflect the true subjective satisfaction of the patient. The purpose of this study was to evaluate factors related to subjective satisfaction following microendoscopic foraminotomy for cervical radiculopathy. Methods The subjects consisted of consecutive patients who underwent microendoscopic foraminotomy for cervical radiculopathy. Patient background information and operative data were collected. The NDI, the NRS score for the neck, upper back, and arm, and the EuroQOL-5D (EQ-5D) were assessed preoperatively and 1 year postoperatively. Postoperative subjective satisfaction was also assessed as a direct evaluation of satisfaction, and willingness to undergo the same operation if needed was assessed as an indirect evaluation. Results A total of 42 patients were included in this study. The mean age was 52.9 ± 11.8 years; 19.0% were female and 81.0% were male. The operation time for one level was 57.7 min and the estimated blood loss was minimal in most cases. All NDI, NRS, and EQ-5D scores improved significantly postoperatively. Univariate analyses revealed that the factors related to subjective satisfaction were younger age, non-smoking status, high preoperative NDI score, and low postoperative NRS score for the arm. Factors related to the willingness to undergo the same operation if needed were high preoperative NDI scores, high preoperative NRS scores for the arm, and low preoperative EQ-5D scores. Conclusions Factors related to subjective satisfaction following microendoscopic foraminotomy include younger age, non-smoking status, high preoperative NDI score, high preoperative NRS score for the arm, low preoperative EQ-5D score, and a low postoperative NRS score for the arm.

Abstract Background Knee pain is common and related to knee osteoarthritis. However, there is a discrepancy between knee pain and radiographic osteoarthritis. In the general population, knee pain is associated with psychological and cognitive factors, which would be one explanation for the discrepancy. Limited evidence demonstrates that somatization is associated with knee pain. This study examined the association between disability due to knee pain and a high somatising tendency. Methods Japanese adults (aged 20–64 years) who had experienced knee pain in the past four weeks were included in this study (n = 14,695, 50% women). Data were extracted from a large internet survey. Somatising tendency was assessed using the Somatic Symptom Scale-8 (SSS-8). Disability due to knee pain was categorized into three levels: 1) knee pain without difficulty with activities of daily living (ADL), 2) knee pain with ADL difficulty but without requiring sick leave, and 3) knee pain requiring sick leave. The association between ≥ high somatising tendency (SSS-8 score ≥ 12) as well as very high somatising tendency (SSS-8 score ≥ 16) and disability due to knee pain was examined using logistic regression models adjusted for age, sex, body mass index, depressive symptoms, education level, regular exercise, chronicity of knee pain (≥3 months), osteoarthritis, rheumatoid arthritis, and fibromyalgia. Results Greater disability due to knee pain was associated with a higher odds ratio for ≥ high somatising tendency (adjusted odds ratio (aOR) = 2.36 [2.10–2.66] in group 2 vs. group 1, aOR = 3.23 [2.66–3.92] in group 3 vs. group 1). Stronger associations were found for a very high somatising tendency (aOR = 2.80 [2.42–3.23] in group 2 vs. group 1, aOR = 4.51 [3.64–5.58] in group 3 vs. group 1). Conclusions Somatization may play a role in disability due to knee pain in the general adult population with knee pain, similar to the role of somatization in low back pain.

Abstract Background Although the efficiency of conservative management for lumbar spinal stenosis (LSS) has been examined, different conservative management approaches have not been compared. We have performed the first comparative trial of three types of conservative management (medication with acetaminophen, exercise, and acupuncture) in Japanese patients with LSS. Methods Patients with L5 root radiculopathy associated with LSS who visited our hospital for surgical treatment were enrolled between December 2011 and January 2014. In this open-label study, patients were assigned to three treatment groups (medication, exercise, acupuncture) according to the visit time. The primary outcomes were Zurich claudication questionnaire (ZCQ) scores before and after 4 weeks of treatment. Least square mean analysis was used to assess the following dependent variables in the treatment groups: changes in symptom severity and physical function scores of the ZCQ and the ZCQ score of patient’s satisfaction after treatment. Results Thirty-eight, 40, and 41 patients were allocated to the medication, exercise, and acupuncture groups, respectively. No patient underwent surgical treatment during the study period. The symptom severity scores of the ZCQ improved significantly after treatment in the medication (p = 0.048), exercise (p = 0.003), and acupuncture (p = 0.04) groups. The physical function score improved significantly in the acupuncture group (p = 0.045) but not in the medication (p = 0.20) and exercise (p = 0.29) groups. The mean reduction in the ZCQ score for physical function was significantly greater for acupuncture than for exercise. The mean ZCQ score for treatment satisfaction was significantly greater for acupuncture than for medication. Conclusions Acupuncture was significantly more effective than physical exercise according to the physical function score of the ZCQ and than medication according to the satisfaction score. The present study provides new important information that will aid decision making in LSS treatment. Trial registration This study was registered with the UMIN Clinical Trials Registry ( UMIN000006957 ).

Dietary habits are of considerable interest as a modifiable factor for the maintenance of muscle health, especially sarcopenia. The present study aimed to investigate the association between dietary intake and sarcopenia prevalence in community-dwelling Japanese subjects. This cross-sectional study was conducted using data from the fifth survey of the Research on Osteoarthritis/Osteoporosis against Disability (ROAD) study, and 1345 participants (437 men and 908 women) aged ≥60 years were included in the analysis. Sarcopenia was determined by the definition of the Asian Working Group for Sarcopenia established in 2014, and dietary intake was assessed with the brief-type self-administered diet history questionnaire. Overall, 77 subjects (5.7%) were identified as having sarcopenia, 5.0% of men and 6.1% of women. Multiple logistic regression analysis showed that the odds ratios of sarcopenia for the dietary intake of vitamin E (α-tocopherol, 0.14 (CI 0.04–0.49), β-tocopherol (0.24, CI 0.07–0.78), γ-tocopherol (0.28, CI 0.09–0.87), and fats (fat 0.27, CI 0.08–0.96; monounsaturated fatty acids, 0.22, CI 0.07–0.72, polyunsaturated fatty acids, 0.28, CI 0.09–0.89) at the highest quantile were significantly lower compared with those at the lowest quantile. Therefore, higher dietary intakes of vitamin E and fats would be associated with a lower prevalence of sarcopenia.

Objectives: To determine standard reference values for isometric knee extension force using a cohort of Japanese type 2 diabetic patients without diabetic polyneuropathy. Methods: Patient data were collected from the Multicenter Survey of the Isometric Lower Extremity Strength in Type 2 Diabetes study and compared with previously published data of healthy control subjects. In total, we enrolled 898 patients with type 2 diabetes aged 30–87 years, who did not have diabetic polyneuropathy. The control group included 510 healthy subjects aged 30–88 years. Maximum isometric knee extension force (KEF) values were obtained by using a hand-held dynamometer with belt stabilization. In addition, KEF (kgf) was adjusted for bodyweight (kg) to calculate %KEF. Results: KEF and %KEF decreased with age in both patients with diabetes and healthy control subjects. The mean values of KEF and %KEF in patients with diabetes were reduced by 9.7% and 20.8%, respectively, in males, and by 11.6% and 23.0%, respectively, in females compared to the values in healthy control subjects. Conclusion: KEF and %KEF in patients with type 2 diabetes without diabetic polyneuropathy may reduce by approximately 10% and 20%, respectively, compared to these values in healthy control subjects. This study provides reference values for isometric KEF with respect to sex in a population covering a wide age range.

Background and objectives: Global sagittal imbalance with lumbar hypo-lordosis can cause low back pain (LBP) during standing and/or walking. This condition has recently been well-known as one of the major causes of reduced health-related quality of life (HRQOL) in elderly populations. Decrease in disc space of anterior elements and an increase in the spinous process height of posterior elements may both contribute to the decrease in lordosis of the lumbar spine. To correct the sagittal imbalance, the mainstream option is still a highly invasive surgery, such as long-segment fusion with posterior wedge osteotomy. Therefore, we developed a treatment that is partial resection of several spinous processes of thoraco-lumbar spine (PRSP) and lumbar extension exercise to improve the flexibility of the spine as postoperative rehabilitation. Materials and Methods: Consecutively, seven patients with over 60 mm of sagittal vertical axis (SVA) underwent PRSP. The operation was performed with several small midline skin incisions under general anesthesia. After splitting the supraspinous ligaments, the cranial or caudal tip of the spinous process of several thoraco-lumbar spines was removed, and postoperative rehabilitation was followed to improve extension flexibility. Results: The average follow-up period was 13.0 months. The average blood loss and operation time were 11.4 mL and 47.4 min, respectively. The mean SVA improved from 119 to 93 mm but deteriorated in one case. The mean numerical rating scale of low back pain improved from 6.6 to 3.7 without any exacerbations. The mean Oswestry Disability Index score was improved from 32.4% to 19.1% in six cases, with one worsened case. Conclusions: We performed PRSP and lumbar extension exercise for the patients with LBP due to lumbar kyphosis. This minimally invasive treatment was considered to be effective in improving the symptoms of low back pain and HRQOL, especially of elderly patients with lumbar kyphosis.

Purpose: Joint pain is the most common symptom of osteoarthritis (OA); however, its mechanism remains unclarified. The present study investigated hindlimb motion during locomotion on the treadmill using a three-dimensional (3D) motion analysis system with high-speed cameras to evaluate whether this method can be used as an indication of joint pain in a mouse model of surgically induced OA. Methods: We resected the medial meniscus and medial collateral ligament in 8-week old C57BL/6 male mice and performed locomotion recording 6 months post-operatively. Additionally, we performed the same recording after oral administration of the selective cyclooxygenase-2 inhibitor to determine whether alteration of the parameters were associated with joint pain. Results: OA development, characterized by cartilage degeneration and osteophyte formation, was markedly enhanced in the OA group. There was no significant difference between the sham and OA groups in basic gait parameters, including stance duration, swing duration and gait cycle. However, when we divided the gait cycle into four phases and calculated the joint ranges of motion in each phase, the range of motion of the knee joint during the stepping-in phase and the swing duration were significantly decreased in the OA group. These significant differences between the sham and OA groups were diminished by the oral administration of a selective cyclooxygenase-2 inhibitor to the OA group. Conclusion: The present method may be useful to evaluate joint pain in experimental mice and contribute to elucidating the molecular mechanisms of pain in the OA knee joint in combination with genetically modified mice.

BACKGROUND:Although poor standing posture is a known cause of low back pain, the mechanisms involved are unclear. The aim of this study was to clarify the kinetic and posture angle features of standing posture that might influence low back pain. METHODS:Sixty-seven young men were enrolled in this cross-sectional case-control study and were categorized according to whether they did or did not have low back pain. Habitual standing posture was assessed in each group, using a three-dimensional motion analysis system, force plates, and a spinal mouse. Kinetic and posture angle factors were compared between participants with and without low back pain. The relationship between specific features of standing posture and low back pain was analyzed using logistic regression. RESULTS:The intervertebral disc compressive force and the low back moment were significantly greater in the group with low back pain than in the group without low back pain. The intervertebral disc compressive force was the factor most strongly associated with low back pain during static standing. CONCLUSIONS:Logistic regression analysis identified intervertebral disc compressive force as an independent variable associated with low back pain. This finding suggests that increased intervertebral disc compressive force may promote development of low back pain in standing posture.

Depression is a relevant risk factor for low back pain and is associated with the outcomes of low back pain. Depression also often overlaps with somatisation. As previous studies have suggested that somatisation or a higher somatic symptom burden has a role in the outcomes of low back pain, the aim of the present cross-sectional study was to examine whether somatic symptom burden was associated with health-related quality of life in individuals with chronic low back pain independent of depression. We analyzed internet survey data on physical and mental health in Japanese adults aged 20-64 years with chronic low back pain (n = 3,100). Health-related quality of life was assessed using the EuroQol five dimensions (EQ-5D) questionnaire. Somatic symptom burden and depression were assessed using the Somatic Symptom Scale-8 (SSS-8) and the Patient Health Questionnaire-2 (PHQ-2), respectively. SSS-8 score was categorized as no to minimal (0-3), low (4-7), medium (8-11), high (12-15), and very high (16-32). The association between SSS-8 and EQ-5D was examined using linear regression models, adjusting for depression and other covariates, including age, sex, BMI, smoking, marital status, education, exercise, employment, and the number of comorbid diseases. A higher somatic symptom burden was significantly associated with a lower health-related quality of life independent of depression and the number of comorbid diseases (regression coefficient = 0.040 for SSS-8 high vs. very high and 0.218 for non to minimal vs. very high, p trend

OBJECTIVE:Patients with lumbar spinal stenosis (LSS) who have radiographically similar degrees of stenosis may not necessarily exhibit equivalent symptoms. As part of a cross-sectional study, we examined factors associated with symptomatic LSS (sLSS) in the general population of Japan. METHODS:We evaluated 968 participants (men, 319; women, 649) between 2008 and 2010. Orthopedic surgery specialists diagnosed sLSS using interview results, medical examinations, and imaging findings. LSS was radiographically graded using a 4-level scale. Additionally, we examined basic anthropometry, smoking habits, alcohol consumption, ankle-brachial index values (ABI), and glycosylated hemoglobin (HbA1c) levels. We grouped patients with moderate and severe radiographic LSS, and compared the indicated factors on the basis of the presence/absence of sLSS. Data were evaluated using multiple logistic regression analyses. RESULTS:Radiographically, 451 participants had moderate and 288 severe stenosis. Clinically, 92 participants were diagnosed with sLSS, including 36 with moderate and 52 with severe stenosis. In the moderate stenosis group, participants with sLSS had significantly higher rates of diabetes mellitus (DM) and lower ABIs than did non-LSS participants. Although sLSS participants tended to be older (p = 0.19), there were no significant differences in the sex distribution, body mass index values, or in the percentages of participants who were drinkers/smokers. In the severe stenosis group, there were no differences in any of the evaluated factors. Multiple logistic regression showed that DM (odds ratio [OR], 3.92; 95% confidence interval [CI], 1.52-9.34]) and low ABI (1 SD = 0.09; OR, 1.36; 95% CI, 1.04-1.81) were significantly associated with LSS in the moderate stenosis group. CONCLUSIONS:DM and low ABIs are significantly associated with sLSS in patients with moderate radiographic stenosis. Neither factor is associated with sLSS in patients with severe stenosis. Notably, the effects of intrinsic factors on symptomology may be masked when anatomic stenosis is severe.

Surgical site infection (SSI) is a significant complication after spinal surgery and is associated with increased hospital length of stay, high healthcare costs, and poor patient outcomes. Accurate identification of risk factors is essential to develop strategies to prevent wound infections. The aim of this prospective multicenter study was to determine the independent factors associated with SSI in posterior lumbar surgeries without fusion (laminectomy and/or herniotomy) for degenerative diseases in adult patients. From July 2010 to June 2014, we conducted a prospective multicenter surveillance study in adult patients who developed SSI after undergoing lumbar laminectomy and/or discectomy in ten participating hospitals. Detailed patient and operative characteristics were prospectively recorded using a standardized data collection format. SSI was based on the Centers for Disease Control and Prevention definition. A total of 4027 consecutive adult patients were enrolled, of which 26 (0.65%) developed postoperative SSI. Multivariate regression analysis indicated two independent factors. An operating time >2 h (P = 0.0095) was a statistically significant independent risk factor, whereas endoscopic tubular surgery (P = 0.040) was a significant independent protective factor. Identification of these associated factors may contribute to surgeons' awareness of the risk factors for SSI and could help counsel the patients on the risks associated with lumbar laminectomy and/or discectomy. Furthermore, this study's findings could be used to develop protocols to decrease SSI risk. To the best of our knowledge, this is the first prospective multicenter study that identified endoscopic tubular surgery as an independent protective factor against SSI after lumbar posterior surgery without fusion.

Objective: We aimed to compare the efficacies of rehabilitation with the hybrid assistive limb and conventional rehabilitation after total knee arthroplasty. Materials and methods: A total of 37 consecutive patients who underwent primary total knee arthroplasty for knee osteoarthritis were enrolled. Seven patients withdrew from the study after randomization, and 30 patients (hybrid assistive limb group: n = 16; conventional group: n = 14) completed the randomized controlled trial. Patients in the hybrid assistive limb group underwent ten 20-min rehabilitation sessions with the hybrid assistive limb as well as 20-min conventional sessions over the course of 2 weeks, whereas patients in the conventional group received ten 40-min conventional sessions during the same period. The primary outcome measure was walking speed, whereas the secondary outcome measures included quadriceps strength and knee pain assessed using a numerical rating scale. The outcome measures were evaluated prior to surgery and on postoperative weeks 1, 2, and 3. Results: In the early postoperative period, rehabilitation after total knee arthroplasty with the hybrid assistive limb resulted in a significantly greater improvement in walking speed (weeks 1 and 2: p = 0.045), quadriceps strength (weeks 1 and 2; weeks 1 and 3: p