Epidemiology of the locomotive syndrome: The research on osteoarthritis/osteoporosis against disability study 2005-2015

Locomotive syndrome and depressive symptoms: A cross-sectional study in middle-aged women

OBJECTIVE

Evidence for an association between locomotive syndrome (LS) and depression is lacking in middle-aged women. This study aimed to investigate the relationship between LS severity and depressive symptoms in community-dwelling middle-aged women.

METHODS

This cross-sectional study included 1520 middle-aged women (mean age 52 ± 6 years). LS severity was evaluated using the 25-question Geriatric Locomotive Function Scale questionnaire and motor function test. Depressive symptoms were assessed using the Zung self-rating depression scale. Multiple logistic regression analyses were performed to determine the association between depressive symptoms and LS severity, adjusting for potential confounding factors.

RESULTS

LS severity, as evaluated through both questionnaires and motor function tests, was significantly associated with depressive symptoms (self-rating depression scale  ≥ 40 points) in middle-aged women. The relationship between LS and depressive symptoms was only significant when assessed through the 25-question Geriatric Locomotive Function Scale questionnaire rather than the motor function tests. Additionally, a stepwise association was observed between pain severity, as assessed by the 25-question Geriatric Locomotive Function Scale, and the prevalence of depressive symptoms.

CONCLUSIONS

LS severity is significantly associated with depressive symptoms in community-dwelling middle-aged women, suggesting the need for additional mental status assessment in participants with LS and concurrent pain.

The effects of nonpharmacological sleep hygiene on sleep quality in nonelderly individuals: A systematic review and network meta-analysis of randomized controlled trials

The prevalence of locomotive syndrome naturally increases with age, but approximately half of nonelderly individuals also meet the criteria for locomotive syndrome, suggesting that even younger people need to pay attention to their own health status. Sleep is important for physical, cognitive, and psychological health. Some individuals with poor sleep quality may be at risk of developing negative health status. Although the effects of sleep hygiene strategies for elderly individuals have been well investigated, optimal nonpharmacological sleep hygiene strategies for improving sleep quality in nonelderly individuals has not been identified. We conducted a systematic review and network meta-analysis (NMA) of randomized controlled trials aimed to elucidate the effects of various nonpharmacological interventions on sleep quality in nonelderly individuals and to identify the optimal intervention. Cochrane Central Register of Controlled Trials, Medline, Cumulative Index to Nursing and Allied Health Literature, Physiotherapy Evidence Database, and Scopus were comprehensively searched. We identified 27 studies focusing on the effects of various nonpharmacological sleep hygiene strategies in nonelderly individuals, and 24 studies were applied into NMA. The present results showed that resistance training was the most effective intervention for improving sleep quality in nonelderly individuals. In addition, this study revealed the effects of nonpharmacological interventions, such as physical activity, nutritional intervention, as well as exercise interventions. This is the first report that utilized NMA to compare the effects of various nonpharmacological interventions on sleep quality in nonelderly individuals.

Changes in Health-Related Quality of Life by Patient Education and Rehabilitation Based on a Behavior Change Program in Knee Osteoarthritis

OBJECTIVE

The purpose of this study was to examine how rehabilitation and patient education for knee osteoarthritis improves health-related quality of life (HRQOL) and to identify factors influencing HRQOL.

METHODS

Between May 2020 and March 2022, 30 patients with osteoarthritis of the knee were treated conservatively and rehabilitated with a patient education program. The patient education program was based on the health belief model by Sedlak et al., and patient education using pamphlets was provided during the rehabilitation intervention. The survey items were patient basic information, instrumental activities of daily living (ADL) (FAI), fear of falling (FES), degree of depression (GDS), HRQOL (SF-8), knee function assessment (JOA score), and X-ray classification (K-L classification), and the survey method was a self-administered questionnaire at the start of rehabilitation, 1 month after the intervention, and at the end of the rehabilitation intervention. We examined factors affecting the physical component summary (PCS) and mental component summary (MCS) of HRQOL scores.

RESULTS

JOA score, FES, FAI, GDS, and SF-8 improved significantly (p<0.01). MCS was also negatively correlated with FES and age (r=-0.486, -0.368). Sex was extracted as a factor for PCS as a factor affecting HRQOL (p<0.01). MCS was extracted with FES as a factor (p=0.046).

CONCLUSION

A rehabilitation intervention incorporating patient education in osteoarthritis of the knee showed improvement in HRQOL and may be useful for improving depression, fear of falling, and instrumental ADL.

TPX2 upregulates MMP13 to promote the progression of lipopolysaccharide-induced osteoarthritis

Purpose

This study seeks to identify potential clinical biomarkers for osteoarthritis (OA) using bioinformatics and investigate OA mechanisms through cellular assays.

Methods

Differentially Expressed Genes (DEGs) from GSE52042 (four OA samples, four control samples) were screened and analyzed with protein-protein interaction (PPI) analysis. Overlapping genes in GSE52042 and GSE206848 (seven OA samples, and seven control samples) were identified and evaluated using Gene Set Enrichment Analysis (GSEA) and clinical diagnostic value analysis to determine the hub gene. Finally, whether and how the hub gene impacts LPS-induced OA progression was explored by in vitro experiments, including Western blotting (WB), co-immunoprecipitation (Co-IP), flow cytometry, etc.

Result

Bioinformatics analysis of DEGs (142 up-regulated and 171 down-regulated) in GSE52042 identified two overlapping genes (U2AF2, TPX2) that exhibit significant clinical diagnostic value. These genes are up-regulated in OA samples from both GSE52042 and GSE206848 datasets. Notably, TPX2, which AUC = 0.873 was identified as the hub gene. In vitro experiments have demonstrated that silencing TPX2 can alleviate damage to chondrocytes induced by lipopolysaccharide (LPS). Furthermore, there is a protein interaction between TPX2 and MMP13 in OA. Excessive MMP13 can attenuate the effects of TPX2 knockdown on LPS-induced changes in OA protein expression, cell growth, and apoptosis.

Conclusion

In conclusion, our findings shed light on the molecular mechanisms of OA and suggested TPX2 as a potential therapeutic target. TPX2 could promote the progression of LPS-induced OA by up-regulating the expression of MMP13, which provides some implications for clinical research.

Reliability and validity tests of the Chinese version of the Geriatric Locomotive Function Scale (GLFS-25) in tumor survivors

Objective

To evaluate the reliability and validity of the Chinese-translated Geriatric Locomotive Function Scale (GLFS-25) for the assessment of locomotive syndrome (LS) in individuals surviving malignancies.

Methods

393 tumor survivors at a general hospital in China were recruited. The Chinese version of GLFS-25 was utilized to conduct a cross-sectional survey to ascertain the tool's efficacy in measuring LS in this cohort. The scale's validity was examined through content, structural and discriminant validity assessments, while its reliability was investigated by determining the internal consistency (via Cronbach's α coefficient) and test-retest reliability (via intragroup correlation coefficient, ICC).

Results

The Chinese-adapted GLFS-25 demonstrated a robust scale-level content validity index of 0.94, while item-level content validity indices ranged from 0.83 to 1.00 across individual items. The suitability of the scale for structural validity assessment was confirmed via exploratory factor analysis, yielding a Kaiser-Meyer-Olkin measure of 0.930 and a significant Bartlett's test of sphericity (χ2 = 3217.714, df = 300, P < 0.001). Subsequent confirmatory factor analysis (CFA) extracted four distinct factors: Social Activity Engagement, Daily Living Ability, Pain Experience and Physical Mobility. These factors accounted for 72.668 % of the variance, indicating substantial construct validity for measuring LS among this population. CFA supported the model's fit with the following indices: χ2/df = 1.559, RMSEA = 0.077, GFI = 0.924, CFI = 0.941, NFI = 0.919, and TLI = 0.933. The factor loadings for the four factors ranged from 0.771 to 0.931, indicating the items corresponding to the four factors effectively represented the constructs they were designed to measure. The correlation coefficients among the four factors were between 0.306 and 0.469, all lower than the square roots of the respective AVEs (0.838-0.867). This suggests a moderate correlation among the four factors and a distinct differentiation between them, indicating the Chinese version of the GLFS-25 exhibits strong discriminant validity in Chinese tumor survivors. Reliability testing revealed a high Cronbach's α coefficient for the overall scale at 0.961, with the subscales yielding coefficients of 0.751, 0.836, 0.930, and 0.952. The overall ICC was determined to be 0.935, with subscale ICCs ranging from 0.857 to 0.941, reinforcing the scale's reliability in this context.

Conclusions

The Chinese version of the GLFS-25 exhibits strong reliability and validity for the assessment of LS in tumor survivors. It may serve as a diagnostic tool for LS, contributing to the prevention and management of musculoskeletal disorders and enhancing the prognosis for this patient population.

Safety and feasibility of in-hospital autonomous transportation using a driverless mobility for patients with musculoskeletal disorders: preliminary clinical study to achieve mobility as a service in medical care

BACKGROUND

Recent advancements in and the proliferation of autonomous mobility technology, such as intelligent wheelchairs, have made it possible to provide mobility services for patients with reduced mobility due to musculoskeletal disorders. In the present study, we conducted a preliminary clinical study to assess the safety and feasibility of in-hospital autonomous transportation using a driverless mobility (wheelchair) for patients with musculoskeletal disorders.

METHODS

From January to February 2022, 51 patients with musculoskeletal disorders exhibiting gait disturbance who presented to our institution were included in the present study. Driverless mobility rides were conducted over a straight-line distance of 100 m from the orthopaedic outpatient reception to the payment counter after the outpatient consultation. We assessed the quality of life using an EQ-5D-5 L index and pain using a VAS score before riding the mobility to investigate the patient's condition. After the ride, a questionnaire survey was conducted to assess patient satisfaction on a 5-point scale. In addition, adverse events during the mobility ride were investigated.

RESULTS

Overall satisfaction levels showed that 44 out of 51 (86%) patients rated the level as 3 or higher. There were no significant differences in the level of satisfaction based on the cause of disorders or EQ-5D-5 L Index. Among 19 patients who rated the level of satisfaction as 2-3, the ratio of postoperative patients and those with pain tended to be higher (p < 0.05). While 26 of 51 (51%) patients reported moments of feeling unsafe during the mobility ride, no actual adverse events, such as collisions, were observed.

CONCLUSIONS

An in-hospital autonomous transportation service using a driverless mobility for patients with musculoskeletal disorders demonstrated high satisfaction levels and was safe with no severe adverse events observed. The expansion of autonomous mobility deployment is expected to achieve mobility as a service in medical care.

Hybrid Closed Wedge High Tibial Osteotomy Maintains the Leg Length After Surgery Compared With Open Wedge High Tibial Osteotomy

BACKGROUND

This study aimed to assess the changes in leg length following open wedge high tibial osteotomy (OWHTO) and hybrid closed wedge high tibial osteotomy (h-CWHTO) and whether the change in leg length was associated with preoperative radiographic factors and the change in planned opening or closing width.

METHODS

We retrospectively evaluated the data of patients who underwent OWHTO (n=57) and h-CWHTO (n=31) between 2016 and 2019. Standing full-length anteroposterior radiographs were obtained preoperatively and one year postoperatively. Changes in the lower leg and tibial length were measured using radiography, and the planned opening or closing width was decided via operative planning. Flexion contracture was examined preoperatively and one year postoperatively using a goniometer, and the correlation factors and changes in leg length were analyzed using Spearman's rank correlation.

RESULTS

In the OWHTO group, the lower leg was significantly longer by a mean of 6.0±8.7 mm compared to that preoperatively (p<0.01); however, no significant difference was observed in the h-CWHTO group (mean, -0.56±11.6 mm) (p=0.788). In the OWHTO group, flexion contracture did not improve after surgery, however, in the h-CWHTO group, flexion contracture significantly improved from -7.1±7.0 degrees to -4.7±6.2 degrees postoperatively (p<0.01). No radiographic factors or bone opening or closing width were associated with changes in leg length in both groups.

CONCLUSION

OWHTO led to a significant elongation of the lower leg while leg length was maintained post-h-CWHTO. However, the changes in leg length following both OWHTO and h-CWHTO were not predictable from preoperative radiographic factors or changes in bone width.

Risk factors for progression of the severity of locomotive syndrome: A two-year longitudinal observational study

BACKGROUND

The risk factors for progression of severity of locomotive syndrome (LS) remain unclear.

METHODS

We conducted a longitudinal observational study of 1148 community-dwelling residents (median age, 68.0 years old; 548 males, 600 females) from 2016 to 2018. LS was assessed by the 25-question Geriatric Locomotive Function Scale (GLFS-25), and total scores of ≤6 points, 7-15 points, 16-23 points, and ≥24 points were diagnosed as non-LS, LS-1, LS-2, and LS-3, respectively. If the LS severity in 2018 was higher than in 2016, the case was defined as progression of LS severity; otherwise, it was defined as non-progressive LS. We compared the age, gender, body mass index, smoking status, alcohol consumption, living situation, car use, chronic musculoskeletal pain, comorbidities, metabolic syndrome, physical activity, and LS severity in 2016 between the progression and non-progression groups. Furthermore, a multivariate logistic regression analysis was performed to elucidate the risk factors for progression of LS severity.

RESULTS

Participants in the progression group had a significantly older age, a lower rate of car use, a higher rate of low back pain, a higher rate of hip pain, a higher rate of knee pain, a higher GLFS-25 total score, and a higher rate of LS-2 than those in the non-progression group. The multivariate logistic regression analysis revealed that older age, female gender, higher body mass index (≥25.0 kg/m2), presence of low back pain, and presence of hip pain were risk factors for the progression of LS within two years.

CONCLUSIONS

To prevent the progression of LS severity, related prophylaxis strategies should be implemented, especially for individuals with the above-mentioned characteristics. Further longitudinal studies with a longer observation period are necessary.

Temporal validation of a clinical prediction rule for distinguishing locomotive syndromes in community-dwelling older adults: A cross-sectional study from the DETECt-L study

Objectives

Clinical prediction rules are used to discriminate patients with locomotive syndrome and may enable early detection. This study aimed to validate the clinical predictive rules for locomotive syndrome in community-dwelling older adults.

Methods

We assessed the clinical prediction rules for locomotive syndrome in a cross-sectional setting. The age, sex, and body mass index of participants were recorded. Five physical function tests-grip strength, single-leg standing time, timed up-and-go test, and preferred and maximum walking speeds-were measured as predictive factors. Three previously developed clinical prediction models for determining the severity of locomotive syndrome were assessed using a decision tree analysis. To assess validity, the sensitivity, specificity, likelihood ratio, and post-test probability of the clinical prediction rules were calculated using receiver operating characteristic curve analysis for each model.

Results

Overall, 280 older adults were included (240 women; mean age, 74.8 ± 5.2 years), and 232 (82.9%), 68 (24.3%), and 28 (10.0%) participants had locomotive syndrome stages ≥ 1, ≥ 2, and = 3, respectively. The areas under the receiver operating characteristics curves were 0.701, 0.709, and 0.603, in models 1, 2, and 3, respectively. The accuracies of models 1 and 2 were moderate.

Conclusions

These findings indicate that the models are reliable for community-dwelling older adults.

Association between Obesity and Short-Term Patient-Reported Outcomes following Total Knee Arthroplasty: A Retrospective Cohort Study in Japan

Background: This study investigated the association between obesity and short-term patient-reported outcomes after total knee arthroplasty (TKA). Methods: The primary outcomes were the Western Ontario and McMaster Universities Osteoarthritis Index's (WOMAC) pain and function scores. Data were collected preoperatively and 2 and 4 weeks after surgery. Patients were stratified into three groups based on body mass index (BMI): normal weight (BMI < 24.99 kg/m2), overweight (25 ≤ BMI < 29.99 kg/m2), and obese (BMI ≥ 30 kg/m2). The associations between BMI and the WOMAC pain and function scores were assessed using generalized linear mixed models. Results: Among the 102 patients (median age: 75.0, women [85.3%]), 29.4%, 48.0%, and 22.5% were normal weight, overweight, and obese, respectively. The mean pain and function scores at baseline were similar across the BMI-stratified groups (p = 0.727 and 0.277, respectively). The pain score significantly improved 2 weeks post-surgery (p = 0.001). The function score improved significantly 4 weeks post-surgery (p < 0.001). The group and group-by-time interaction effects lacked statistical significance. Conclusions: All patients statistically and clinically showed relevant pain reduction and functional improvement shortly after TKA, irrespective of their obesity status. These data may help healthcare professionals discuss the expectations of pain amelioration and functional improvement with TKA candidates.

Validating Knee Varus Alignment Measurements Using Markerless Motion Capture

This study aimed to determine the validity of specific knee varus alignment measurement methods. We measured the femorotibial angle (FTA) using radiography and optical motion capture and validated the FTA measurement using markerless motion capture. The subjects included 34 legs of 19 patients with knee osteoarthritis (OA). One-way analysis of variance and multiple comparison tests were used to compare the FTA values between the Kellgren-Lawrence classification (KL) and Pearson's correlation coefficient for validity. The analysis showed that the FTA measured by markerless motion capture had a significant correlation to the FTA measured by radiography (r = 0.869, p < 0.01) and significantly increased with increasing KL (p < 0.05). These results indicate that markerless motion capture is a valid outcome measure for varus alignment in patients with knee OA.

Readability and quality of online patient resources regarding knee osteoarthritis and lumbar spinal stenosis in Japan

BACKGROUND

This study aimed to quantify the readability and quality of online patient resources on knee osteoarthritis and lumbar spinal stenosis in Japan.

METHODS

Three search engines (Google, Yahoo, and Bing) were searched for the terms knee osteoarthritis and lumbar spinal stenosis. The first 30 websites of each search were screened. Duplicate websites and those unrelated to the searched diseases were excluded. The remaining 125 websites (62 on knee osteoarthritis, 63 on lumbar spinal stenosis) were analyzed. The text readability was assessed using two web-based programs (Obi-3 and Readability Research Lab) and lexical density. Website quality was evaluated using the DISCERN score, Clear Communication Index, and Journal of American Medical Association benchmark criteria.

RESULTS

Readability scores were high, indicating that the texts were difficult to understand. Only 24 (19%) and six (5%) websites were classified as average difficulty readability according to Obi-3 and Readability Research Lab, respectively. The overall quality of information was low, with only four (3%) being rated as having sufficient quality based on the Clear Communication Index and Journal of American Medical Association benchmark criteria. None of the websites satisfied the DISCERN quality criteria.

CONCLUSIONS

Patient information on Japanese websites regarding knee osteoarthritis and lumbar spinal stenosis were difficult to understand. Moreover, the quality of the websites was insufficient. Orthopaedic surgeons should contribute to the creation of high-quality easy-to-read websites to facilitate patient-physician communication.

Can the measurement of Locomo Age improve motivation for exercise in fitness club users?

AIM

In 2022, the Japanese Orthopaedic Association developed "Locomo Age," which can be used to measure mobility. The potential effects of measuring Locomo Age on motivation to exercise are yet to be explored. This study aimed to determine whether the measurement of Locomo Age improved motivation for exercise.

METHODS

In total, 90 fitness club users (17 men and 73 women) were enrolled in the study. The participants performed the locomotive syndrome risk test. These results were entered on a smartphone website, and their Locomo Age was automatically calculated. Questionnaires about impressions of Locomo Age and changes in motivation for exercise after measuring Locomo Age were surveyed.

RESULTS

The mean Locomo Age of the participants was 84.4 ± 8.5 years, which was significantly higher than their actual age (75.9 ± 7.2 years, P < 0.001). Questionnaires showed that 55 participants (61.1%) felt that their Locomo Age was higher than expected; 42 participants (46.7%) had increased motivation for exercise, and only two participants (2.2%) had decreased motivation. The rate of improvement in motivation for exercise was higher in the group of participants who reported having an older Locomo Age than they expected compared with that of the group with a Locomo Age that was the same as they expected (P < 0.05).

CONCLUSIONS

The measurement of Locomo Age improved the motivation for exercise. This result remained true even when the Locomo Age was higher than expected, as it did not decrease the participants' motivation. Locomo Age allows for the comprehension of participants' mobility without medical knowledge. Geriatr Gerontol Int 2023; ••: ••-••.

Clinical characteristics of locomotive syndrome categorised by the 25-question Geriatric Locomotive Function Scale: a systematic review

OBJECTIVES

The purpose of this study was to compile the currently available evidence on the clinical characteristics of the locomotive syndrome (LS) categorised by the 25-question Geriatric Locomotive Function Scale (GLFS-25) and clarify its clinical usefulness for assessing mobility function.

DESIGN

Systematic review.

DATA SOURCES

The PubMed and Google Scholar were searched for the relevant studies on 20 March 2022.

ELIGIBILITY CRITERIA

We included relevant peer-reviewed articles, available in English language, on clinical LS characteristics categorised with the GLFS-25.

DATA EXTRACTION AND SYNTHESIS

Pooled ORs or mean differences (MDs) of the LS groups were calculated and compared with the non-LS groups for each clinical characteristic.

RESULTS

In total, 27 studies that involve 13 281 participants (LS, n=3385; non-LS, n=9896) were examined in this analysis. Older age (MD 4.71; 95% (CI) 3.97 to 5.44; p<0.00001), female gender (OR 1.54; 95% CI 1.38 to 1.71; p<0.00001), higher body mass index (MD 0.78; 95% CI 0.57 to 0.99; p<0.00001), osteoporosis (OR 1.68; 95% CI 1.32 to 2.13; p<0.0001), depression (OR 3.14; 95% CI 1.81 to 5.44; p<0.0001), lower lumbar lordosis angle (MD -7.91; 95% CI -10.08 to -5.74; p<0.00001), higher spinal inclination angle (MD 2.70; 95% CI 1.76 to 3.65; p<0.00001), lower grip strength (MD -4.04; 95% CI -5.25 to -2.83; p<0.00001), lower back muscle strength (MD -15.32; 95% CI -23.83 to -6.81; p=0.0004), lower maximum stride (MD -19.36; 95% CI -23.25 to -15.47; p<0.00001), higher timed up-and-go (MD 1.36; 95% CI 0.92 to 1.79; p<0.00001), lower one-leg standing time (MD -19.13; 95% CI -23.29 to -14.97; p<0.0001) and slower normal gait speed (MD -0.20; 95% CI -0.22 to -0.18; p<0.0001) were found to be associated with LS. No significant differences were noted in other clinical characteristics between the two groups.

CONCLUSIONS

GLFS-25 is clinically useful for assessing mobility function according to the evidence available on the clinical characteristics of LS categorised by the GLFS-25 questionnaire items until.

Evaluation of Sit-to-Stand Movement in Older Adults with Locomotive Syndrome Using the Nintendo Wii Balance Board

Standing up from a chair is a mechanically demanding daily motion, and its biomechanics represent motor performance. In older adults with locomotive syndrome (LS), sit-to-stand (STS) movement with adequate postural control is essential to prevent falls. This study evaluated the characteristics of dynamic balance during STS movement on older adults with LS. A total of 116 participants aged ≥65 years were divided into Non-LS, LS stage 1, and LS stage 2 groups using the LS risk test. The participants were instructed to stand on the Nintendo Wii Balance Board as quickly as possible, and the STS movement was quantified using the vertical ground reaction force (VGRF) and center of pressure (CoP). The STS score, which represented dynamic balance, was significantly different among the groups (p < 0.001). The rate of VGRF development was significantly lower in the LS stages 1 and 2 than in the Non-LS group (p < 0.001). On the other hand, the total distance of the CoP path did not differ among the groups (p = 0.211). These findings indicated a reduction of postural control in older adults with LS. The STS score emphasized the importance of balance training to prevent falls in older adults with LS.

The prevalence of locomotive syndrome and its associated factors in patients with Type 2 diabetes mellitus

OBJECTIVES

We investigated the prevalence of locomotive syndrome (LS) and related musculoskeletal diseases [osteoarthritis (OA), lumbar spondylosis, and spinal alignment] in Type 2 diabetes mellitus (DM) patients.

METHODS

Clinical data were collected from 101 patients (55 males; 46 females) admitted to our hospital for diabetes education from October 2018 to April 2021. Patients underwent full-spine and whole-legs standing radiography and physical measurements (10-m walking and grip strength tests and three LS risk tests).

RESULTS

The estimated prevalence of LS was 86.1% (Stage 1: 44.5%, Stage 2: 41.6%), lumbar spondylosis was 11.9%, and hip, knee, and ankle OA were 16.9%, 51.5%, and 12.9%, respectively. Multiple logistic regression analysis identified grip strength [odds ratio (OR) = 0.89, confidence interval (CI) = 0.83-0.94], diabetic retinopathy (OR = 5.85, CI = 1.64-20.78), knee OA (OR = 3.34, CI = 1.11-10.02), and a sagittal vertical axis >40 mm (OR = 3.42, CI = 1.13-10.39) as significantly associated risk factors for worsening LS in Type 2 DM patients.

CONCLUSIONS

This study clarified the epidemiological indicators of LS and associated factors in DM patients. Exercise therapy and DM management are effective strategies to reduce the occurrence and progression of LS.

Prevalence of osteoporosis and incidence of related fractures in developed economies in the Asia Pacific region: a systematic review

Robust data on osteoporosis in the Asia Pacific region could improve healthcare decision-making. Osteoporosis affects 10-30% of women aged 40 + , and up to 10% of men in 7 developed economies in Asia Pacific. Fractures affect 500-1000 adults aged 50 + per 100,000 person-years. Policymakers and clinicians must address this problem.

PURPOSE

Osteoporosis and associated fractures result in considerable morbidity, loss of productivity, early mortality, and increased healthcare expenses. Many countries in the Asia Pacific (AP) region, especially middle- and higher-income economies, are faced with aging and increasingly sedentary populations. It is critical to consolidate and analyze the available information on the prevalence and incidence of the disease in these countries.

METHODS

We systematically reviewed articles and gray literature for Australia, China, Hong Kong, Japan, Singapore, South Korea, and Taiwan. We searched PubMed, ScienceDirect, JSTOR, Cochrane, Google Scholar, and other databases for data published 2009-2018. We included articles with prevalence or incidence estimates for adults with osteoporosis or related fractures.

RESULTS

All locations had data available, but of widely varying quantity and quality. Most estimates for osteoporosis prevalence ranged from 10 to 30% for women ages 40 and older, and up to 10% for men. Osteoporotic fracture incidence typically ranged between 500 and 1000 per 100,000 person-years among adults aged 50 and older. Both outcomes typically increased with age and were more common among women.

CONCLUSION

Osteoporosis and associated fractures affect significant portions of the adult population in developed economies in the AP region. Governments and healthcare systems must consider how best to prevent and diagnose osteoporosis, and manage affected individuals, to reduce healthcare costs and mortality associated with fractures.

Projected numbers of knee and hip arthroplasties up to the year 2030 in Japan

BACKGROUND

The aging population is a risk factor for an increase in osteoarthritis, leading to a potential increase in the number of arthroplasties worldwide. This study aimed to calculate the projected numbers of knee and hip arthroplasties in Japan until 2030 using national health insurance claim data.

METHODS

Data on the numbers of knee and hip arthroplasties performed in Japan between 2014 and 2018 were obtained from the National Database of Health Insurance Claims and Specific Health Checkups of Open Data Japan. Demographic data were obtained from the National Institute of Population and Social Security Research. Collected data were categorized into three age subgroups (40-64, 65-74, and ≥75 years) for each sex. Projections were based on the Poisson regression model.

RESULTS

The number of knee arthroplasties in Japan in 2030 was projected to be 4052 for men aged 40-64 years, 6942 for men aged 65-74 years, 14,986 for men aged ≥75 years, 7092 for women aged 40-64 years, 22,957 for women aged 65-74 years, and 58,340 for women aged ≥75 years. The number of hip arthroplasties in Japan in 2030 was predicted to be 8936 for men aged 40-64 years, 9005 for men aged 65-74 years, 5972 for men aged ≥75 years, 27,327 for women aged 40-64 years, 36,416 for women aged 65-74 years, and 37,011 for women aged ≥75 years.

CONCLUSION

The numbers of knee and hip arthroplasties are expected to continue to increase over the next 10 years in Japan in most age groups. These findings are useful for future healthcare resource planning to meet the demand for knee and hip arthroplasties.

Concurrent Validity Between Potential Screening Tests for Early Mobility Decline in Independent Community Dwellers

BACKGROUND AND PURPOSE

Standardized screening tests that detect early mobility decline, regardless of etiology, are needed for healthy aging. The locomotive syndrome (LS) tests are designed to identify stages of mobility decline and inform appropriate levels of intervention. The long-term goal of this research is to develop standardized mobility screening tests that can be used across health care settings and throughout a patient's lifespan to guide appropriate medical care. As the first step in this process, this study examines the concurrent validity between the reference and the LS tests.

METHODS

This cross-sectional study examined correlations between the LS functional tests and a set of reference tests and the ability to differentiate the 3 stages of mobility decline. The reference tests included the stair-climbing test, the 30-second chair rise test, the 6-minute walk test, the Global Physical Health (GPH) portion of the PROMIS, and the Lower Extremity Functional Scale (LEFS). The LS tests included the Stand-Up Test, the 2-Step Test, and the 25-question Geriatric Locomotive Function Scale (25-GLFS). A total of 115 community dwellers of 61.2 years old on average (±10.0 years), with n = 71 (61%) older than 60 years, voluntary participated in this prospective study. Nonparametric analyses of variance and correlations were used to examine the concurrent validity.

RESULTS AND DISCUSSION

Performance-based tests were significantly correlated (| r | = 0.38-0.61, P < .001) with LS tests. The LEFS was correlated with all LS tests, but the GPH was only correlated with the 25-GLFS. Also, significant differences were found in reference test scores between the 3 LS stages ( P < .05).

CONCLUSIONS

The LS tests and reference tests demonstrated significant correlations, and participants performed significantly worse on reference tests as LS severity increased. Given these results, it is possible that the LS standardized tests may play an important role in mobility screening. Future research should investigate feasibility, sensitivity, and specificity of these tests.

Association between Locomotive Syndrome and Physical Activity in Long-Term Inpatients of Psychiatric Care Wards in Japan: A Preliminary Study

The aim of this cross-sectional study was to determine the status of locomotive syndrome (LS) and the level of physical activity (PA) in long-term inpatients in a psychiatric care ward and to investigate the association between the severity of LS and the level of PA. The study participants consisted of 25 patients aged 55 years or older who had been admitted to a psychiatric care ward for more than one year. The participants’ LS stage was determined and their level of PA was measured using an accelerometer. We also analyzed the correlations between the LS stage test results, level of PA, and values for each assessment item. The LS stage test showed that 84.0% of the participants were at stages 3. The participants’ mean step count was 3089.8 ± 2346.5 steps. The participants’ mean sedentary time was 349.7 ± 68.9 min, which is more than 70% of the total measuring time. Overall, the results indicate that LS stage was significantly correlated to age, ADL, and level of PA. Patients who stay in a psychiatric care ward experience declining motor functioning and lack PA. Deterioration of motor functioning is associated with lack of PA, suggesting the need for physical intervention.

Association between serum insulin-like growth factor 1 and locomotive syndrome in community-dwelling older people

Background

Locomotive syndrome (LS) is a condition in which mobility decreases, and it is known as a risk factor for elderly persons needing care in connection with sarcopenia and frailty. Prevention or delay of the onset of these diseases is important for preventing the need for care, and identification of biomarkers as indicators for appropriate intervention is useful. The present study aimed to clarify whether the serum insulin-like growth factor 1 (IGF-1) level, which has been reported to be related to sarcopenia and frailty, is related to LS.

Methods

The study participants were 133 elderly people living in a rural area in Japan. LS was assessed using Locomo-25, which is a self-administered questionnaire, and LS was defined as a Locomo-25 score ≥ 7 points. Serum IGF-1 and albumin levels were measured. A self-completed medical history questionnaire was used.

Results

On multiple linear regression analysis, age, IGF-1, osteoporosis, and osteoarthritis were significantly associated with the Locomo-25 score. The receiver-operating characteristic curve analysis of the IGF-1 level showed a threshold value of 82.0 ng/mL for discriminating non-LS and LS. The logistic regression analysis adjusted for osteoporosis, osteoarthritis, and the propensity score estimated from sex, age, and BMI showed that the odds ratio (OR) of the IGF-1 level for LS was 1.019 (95% confidence interval [CI], 1.002–1.039; p = 0.027), and the OR of IGF-1 ≤ 82 ng/mL for LS was 2.275 (95% CI 0.993–5.324; p = 0.052).

Conclusions

The present findings suggest that osteoporosis and osteoarthritis were associated with early LS, and a decrease of the serum IGF-1 level was a significant independent factor for early LS.

Risk Factors that Hinder Locomotive Syndrome Improvement Following Surgery for Musculoskeletal Diseases in Older Patients: A Multicenter Prospective Study

OBJECTIVES

This study aimed to evaluate preoperative and postoperative locomotive syndrome (LS) in older adults undergoing surgical treatment for musculoskeletal diseases of the lumbar spine and lower extremities and identify risk factors that impede LS improvement after surgery.

METHODS

: The baseline evaluation included 471 patients 65 years or older (276 in the pre-old age [65-74 years] group; 195 in the old age [75 years or older] group) and examined the preoperative and postoperative LS data. The second evaluation performed to identify risk factors, including anthropometric measurements, comorbidity, and frailty, that hinder LS improvement after surgery included 378 patients with preoperative LS stage 3.

RESULTS

Preoperatively, 80% of the patients had LS stage 3; this rate decreased to 40% postoperatively. Half of the patients exhibited postoperative LS improvement. The LS improvement rate was higher in the pre-old age group than in the old age group. According to the multiple logistic regression analysis, old age, high body mass index, weak hand grip strength, and high 5-factor modified frailty index score were significant risk factors that hinder LS improvement after surgery.

CONCLUSIONS

Aging, obesity, weak muscle strength, and frailty can hinder LS improvement in older patients who undergo surgery.

Association between Daily Physical Activity and Locomotive Syndrome in Community-Dwelling Japanese Older Adults: A Cross-Sectional Study

This study aimed to evaluate the association between locomotive syndrome (LS) and daily physical activity (PA) in community-dwelling older adults. This cross-sectional study included 80 healthy Japanese older adults (40 men and 40 women; age: 60-79 years). Habitual daily PA was evaluated using a triaxial wrist accelerometer. Participants were divided into two groups based on the results of the two-step test, stand-up test, and 25-question geriatric locomotive function scale. Binomial logistic regression analysis was conducted to examine the statistical relationships between daily PA and category of LS, adjusting for age from adjusted odds ratio (adjusted OR) with the 95 percent confidence intervals (95%CI) and bootstrap 95%CI. The mean step count and time spent on moderate to vigorous physical activity (MVPA) were significantly higher among non-LS participants than among LS participants in women, but not in men. Logistic regression analyses indicated that spending longer than 28 min/day on MVPA was significantly associated with a lower likelihood of LS relative to short time category under 28 min/day in women (adjusted OR = 0.12, 95%CI = 0.02-0.59, bootstrap 95%CI = 0.01-0.43), but not in men. This study suggests that in community-dwelling older women, those with higher MVPA had lower odds of LS, and daily MVPA was associated with LS, but not in men. Therefore, the associations between LS and daily physical activity were partly dependent on sex differences.

Epidemiology of locomotive syndrome using updated clinical decision limits: 6-year follow-ups of the ROAD study

INTRODUCTION

Locomotive syndrome (LOCOMO) is defined by the Japanese Orthopaedic Association (JOA) as a condition requiring nursing care due to a decline in mobility resulting from musculoskeletal disorders. In 2020, the JOA announced the new definition of LOCOMO stage 3 and revision of clinical decision limits in stages of LOCOMO. However, there are few reports on the epidemiological indices of LOCOMO. This prospective cohort study aimed to investigate the prevalence, incidence, and association of poor prognosis with LOCOMO stages.

MATERIALS AND METHODS

The third survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study was conducted during 2012-2013, examining a population-based cohort of 1575 participants (513 men and 1062 women, mean age 65.6 years). Three LOCOMO risk tests were performed, and patients were classified into LOCOMO stages 0, 1, 2, and 3. They were followed up for 6 years, and identical examination of LOCOMO was performed in 3- and 6-year follow-ups. Data on patients' prognoses, including disability and death, were collected.

RESULTS

The prevalence of LOCOMO stages 1, 2, and 3 was 41.3, 14.9, and 11.6%, respectively. The incidence of LOCOMO stages 1, 2, and 3 were 83.7, 23.0, and 18.6 per 1000 person-years, respectively. Compared with LOCOMO stage 0, logistic regression analysis showed that LOCOMO stage 3 significantly increased the risk of disability and mortality. In addition, each value of LOCOMO risk tests for LOCOMO stage 3 increased the risk of poor prognosis.

CONCLUSION

LOCOMO stage 3 is a sensitive indicator of future disability and mortality.

Relationship between thigh muscle cross-sectional areas and single leg stand-up test in Japanese older women

In older adults, the quantitative decline of the quadriceps femoris is associated with the augmentation of difficulty in the execution of a stand-up task. However, it is unclear whether the cross-sectional areas (CSAs) of individual thigh muscles differ between older adults who can stand up from a 40-cm-height chair on a single leg and those who cannot. To investigate this, the present study determined the CSAs of individual mid-thigh muscles in 67 Japanese women aged 60–77 years by using a magnetic resonance imaging method. Participants were asked to stand up from a 40-cm-height chair on a single leg, and those who could and could not stand up without leaning back and maintain a standing posture for 3 seconds on a single leg were allocated into the successful group (SG, n = 40) and unsuccessful group (USG, n = 27), respectively. Only the CSA of the adductors (sum of the adductor longus and adductor magnus) was significantly smaller in USG compared to SG. When CSA was expressed relative to the two-third power of body mass, the values for the four heads of the quadriceps femoris and biceps femoris long head, as well as the adductors, were significantly lower in USG than in SG. The current results indicate that in terms of the value relative to body mass, the reduced CSAs of the adductors and biceps femoris long head, as well as the four heads of the quadriceps femoris, are associated with the failure of attempts to stand up from a 40-cm-height chair on a single leg in older women. This may be due to the anatomical function of the two muscle groups, which contributes to hip extension movement involved in transitioning from a sitting position to a standing position during the stand-up task.

Frequency-Response Relationship Between Exercise and Locomotive Syndrome Across Age Groups: Secondary Analysis of a Nationwide Cross-Sectional Study in Japan

OBJECTIVES

This study aimed to clarify the frequency-response relationship between exercise habits and locomotive syndrome in different age groups.

METHODS

We analyzed 8,681 independent community dwellers who participated in a nationwide cross-sectional locomotive syndrome study. Participants were divided into young (20-39 years), middle (40-64 years), and old (≥ 65 years) groups. The presence of locomotive syndrome was evaluated using the locomotive syndrome risk tests. Exercise habits were assessed by exercise frequency (almost every day/sometimes/occasionally/never). The association between locomotive syndrome and exercise was assessed using the multiple logistic regression analysis adjusted for participant characteristics for each age category.

RESULTS

Overall, 3,528 (41%) participants had locomotive syndrome. In the old group, the risk of locomotive syndrome was lower with an increased exercise frequency. However, this dose-response relationship was not found in the young group. The proportion of locomotive syndrome was lower even in participants who occasionally exercised (1-3 days/month) than those who never exercise in the young and middle age groups.

CONCLUSIONS

Regular exercise reduced the risk of locomotive syndrome not only in middle and older adults but also in young adults. Moreover, increasing exercise frequency may provide benefits for locomotive syndrome prevention, especially among older adults.

Development of locomotive syndrome in elderly population after COVID-19 outbreak: A population-based cross-sectional study with over 12,000 participants

BACKGROUND

Restrictions during the coronavirus disease 2019 (COVID-19) pandemic have decreased physical activity levels, which may result in locomotive syndrome. This study evaluated the change in locomotive syndrome prevalence and associated risk factors among an elderly population before and after a coronavirus outbreak.

METHODS

This written self-administered cross-sectional survey was conducted in conjunction with the coronavirus disease vaccination program in Habikino City, Japan. Participants who were aged ≥65 years completed the five-question Geriatric Locomotive Function Scale before and during the pandemic. The diagnosis of locomotive syndrome and its stage was based on the Geriatric Locomotive Function Scale score: stage 1 (2-3 points), 2 (4-5 points), and 3 (≥6 points). Data on lifestyle changes, including regular exercise, during the pandemic were collected.

RESULTS

This study included 12,197 participants (36.7% of the city's total elderly residents). The prevalence of locomotive syndrome increased from 41.3% to 47.1% after the outbreak. In total, 765 (6.3% of overall population) and 295 (9.5% of the participants who had stages 1-2 before the pandemic) participants developed locomotive syndrome and stage 3 locomotive syndrome, respectively. The multivariate logistic regression analysis indicated that a decrease in exercise was significantly associated with the onset of locomotive syndrome (all stages) (odds ratio = 2.5, p < 0.001) and locomotive syndrome stage 3 (odds ratio = 2.6, p < 0.001).

CONCLUSIONS

Extrapolation of the study's findings to the entire population of Japan suggests that approximately 2 million elderly individuals might develop locomotive syndrome after the coronavirus outbreak. Additionally, 10% of the participants with mild-moderate locomotive syndrome before the pandemic may develop severe locomotive syndrome after the outbreak. The greatest risk factor for new-onset or worsening locomotive syndrome was a decrease in daily exercise. Thus, there is an urgent need for adequate exercise guidelines during the coronavirus pandemic, especially for the elderly population.

Effect of combined locomotor training and aerobic exercise on increasing handgrip strength in elderly with locomotive syndrome: A randomised controlled trial

Background

Elderly with the locomotive syndrome is at high risk for fall and fractures. Thus multimodal therapy is needed to minimize the risk.

Objective

Analyzing the effect of combined locomotor training and aerobic exercise on muscle strength in elderly with locomotive syndrome stage 1.

Methods

This study used a pre-test and post-test design with 20 participants (treatment group = 10 participants and control group = 10 participants). The treatment group was given combined locomotor training and aerobic exercise, while the control group was only given aerobic exercise for eight weeks. Locomotor training was provided three times/week with progressive increase of set and repetition at each activity. Meanwhile, aerobic exercise was given seven times/week for 30 min per session. Participants were examined for muscle strength (handgrip strength) before and after the intervention. The analysis included paired t-test and an independent t-test with a p-value <0.05.

Results

The participants' mean age was 73.85 ± 4.75 years, with treatment group = 75.4 ± 4.88 years and control group = 72.3 ± 4.30 years (t = 1.508; 95% CI = −1.220 – 7420; p = 0.149). The HGS values in the treatment group were 13.89 ± 5.27 (pre-test) and 19.06 ± 4.54 (post-test; t = 11.765; 95% CI = −6.164 to −4.176; p < 0.001). Meanwhile, the HGS values in the control group at pre-test and post-test were 11.27 ± 2.17 and 13.03 ± 2.54, respectively (t = 2.057; 95% CI = −1.600 – 0.076; p = 0.070). The ΔHGS values of treatment and control group were 5.17 ± 1.39 and 1.76 ± 2.07, respectively (t = 4.329; 95% CI = 1.755–5.065; p < 0.001).

Conclusion

Combined locomotor training and aerobic exercise have increased muscle strength, as proven by increased handgrip strength.

•

Combined locomotor training and aerobic exercise minimize fall risk and fracture in the elderly.

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Combined locomotor training and aerobic exercise are effective for the management of locomotive syndrome stage 1.

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Combined locomotor training and aerobic exercise reduce the GLFS-25 score.

Mass spectrometry-based proteomics identify novel serum osteoarthritis biomarkers

Background

Osteoarthritis (OA) is a slowly developing and debilitating disease, and there are no validated specific biomarkers for its early detection. To improve therapeutic approaches, identification of specific molecules/biomarkers enabling early determination of this disease is needed. This study aimed at identifying, with the use of proteomics/mass spectrometry, novel OA-specific serum biomarkers. As obesity is a major risk factor for OA, we discriminated obesity-regulated proteins to target only OA-specific proteins as biomarkers.

Methods

Serum from the Osteoarthritis Initiative cohort was used and divided into 3 groups: controls (n=8), OA-obese (n=10) and OA-non-obese (n=10). Proteins were identified and quantified from the liquid chromatography–tandem mass spectrometry analyses using MaxQuant software. Statistical analysis used the Limma test followed by the Benjamini-Hochberg method. To compare the proteomic profiles, the multivariate unsupervised principal component analysis (PCA) followed by the pairwise comparison was used. To select the most predictive/discriminative features, the supervised linear classification model sparse partial least squares regression discriminant analysis (sPLS-DA) was employed. Validation of three differential proteins was performed with protein-specific assays using plasma from a cohort derived from the Newfoundland Osteoarthritis.

Results

In total, 509 proteins were identified, and 279 proteins were quantified. PCA-pairwise differential comparisons between the 3 groups revealed that 8 proteins were differentially regulated between the OA-obese and/or OA-non-obese with controls. Further experiments using the sPLS-DA revealed two components discriminating OA from controls (component 1, 9 proteins), and OA-obese from OA-non-obese (component 2, 23 proteins). Proteins from component 2 were considered related to obesity. In component 1, compared to controls, 7 proteins were significantly upregulated by both OA groups and 2 by the OA-obese. Among upregulated proteins from both OA groups, some of them alone would not be a suitable choice as specific OA biomarkers due to their rather non-specific role or their strong link to other pathological conditions. Altogether, data revealed that the protein CRTAC1 appears to be a strong OA biomarker candidate. Other potential new biomarker candidates are the proteins FBN1, VDBP, and possibly SERPINF1. Validation experiments revealed statistical differences between controls and OA for FBN1 (p=0.044) and VDPB (p=0.022), and a trend for SERPINF1 (p=0.064).

Conclusion

Our study suggests that 4 proteins, CRTAC1, FBN1, VDBP, and possibly SERPINF1, warrant further investigation as potential new biomarker candidates for the whole OA population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02801-1.

Systemic Chronic Diseases Coexist with and Affect Locomotive Syndrome: The Nagahama Study

OBJECTIVES

The concept of locomotive syndrome was proposed to highlight older adults who require nursing care services due to the malfunctioning of their locomotive organs. With the coming of a super-aging society, there is a growing need to understand relation between systemic chronic diseases and locomotive syndrome.

METHODS

We analyzed the second-visit dataset of the Nagahama Study. The association analysis was performed to identify the chronic diseases that were risk factors associated with the occurrence and the progression of locomotive syndrome in both the cross-sectional and longitudinal studies.

RESULTS

Hypertension, stroke, coronary heart disease, rheumatoid arthritis, chronic renal failure, osteoporosis, anemia, and gastroesophageal reflux disease were independently correlated with locomotive syndrome through the deterioration of body pain, social activity, and cognitive function in the cross-sectional study. Multiple chronic diseases had additive effects and significantly increased the risk of locomotive syndrome. In the longitudinal study, osteoporosis and kidney disease were significantly correlated with the worsening of the total GLFS-25 score.

CONCLUSIONS

Locomotive syndrome coexisted with various systemic chronic diseases, especially cardiovascular diseases. Osteoporosis and kidney disease were significantly correlated with the progression of locomotive dysfunction. The management of various chronic diseases may be useful to prevent locomotive syndrome and vice versa.

Clinical prediction rule for locomotive syndrome in older adults: A decision tree model

BACKGROUND

No previous studies have proposed a clinical prediction rule that analyzes the factors related to the severity of locomotive syndrome. This study developed and assessed a clinical prediction rule for the severity of locomotive syndrome in older adults.

METHODS

A total of 186 patients were assessed using the locomotive syndrome risk test. Classification and regression tree methodologies were used to develop the clinical prediction rule. This study developed three prediction models based on the severity of the locomotive syndrome, of which Model 3 assessed the most severe condition. The following potential predictive factors were measured and entered into each model; single-leg standing time, grip strength, preferred and maximum walking time, and timed up and go test.

RESULTS

The single-leg standing test (≤59.4 or >59.4 s) was the best single discriminator for Model 1. Among those with a single-leg standing time >59.4 s, the next best predictor was grip strength (≤37.8 or >37.8 kg). In Model 2, the single-leg standing test was also the best single discriminator (≤12.6 or >12.6 s). Among those with a single-leg standing time ≤12.6, the next best predictor was TUG (≤7.9 or >7.9 s). Additionally, among those with a single-leg standing time >12.6, the next best predictor was single-leg standing time (≤55.3 or >55.3 s). In Model 3, predictive value in Model 2 was the best single discriminator (0 or 1). Among those with 1, the next best predictor was maximum walking time (≤3.75 or >3.75 s). The area under the receiver operating characteristic curves of Models 1, 2, and 3 were 0.737, 0.763, and 0.704, respectively.

CONCLUSIONS

A clinical prediction rule was developed to assess the accuracy of the models. These results can be used to screen older adults for suspected locomotive syndrome.

Proximal Branching of the Anterior Tibial Artery From the Popliteal Artery Increases the Risk of Vascular Injury During Total Knee Arthroplasty: A Retrospective Analysis Using Preoperative Magnetic Resonance Imaging and Intraoperative Findings

Introduction

Arterial injury following total knee arthroplasty (TKA) can be life-threatening. There are some anatomical variations in the popliteal artery (PA) and its branches. In most cases, the PA branches into the anterior tibial artery (ATA) and posterior tibial artery (PTA), which are usually distal to the height of tibial resection in TKA. However, some cases show that the PA branches into the ATA and PTA proximal to the height of tibial resection in TKA. This study aimed to assess the distance from the posterior cortex of the proximal tibia to the anterior wall of the PA or ATA at the height of the tibial cut line, during TKA in the distal and proximal branch groups.

Methods

129 patients (6 patients in the proximal branch group and 123 patients in the distal branch group) were enrolled for this study. For prediction of the distance from the posterior cortex of the proximal tibia to the anterior wall of the PA or ATA, preoperative sagittal and coronal magnetic resonance images and postoperative radiographs were evaluated.

Results

The distance between the posterior cortex of the proximal tibia and the anterior wall of the PA or ATA at the height of the tibial cut line was 1.8 ± 1.1 mm in the proximal branch group and 6.1 ± 2.6 mm in the distal branch group, which was significantly closer in the proximal group (P < .05).

Discussion

The rate of proximal branching was 4.7%. This study clarified that the proximal branching of the ATA from PA significantly decreased the distance between the posterior cortex of the proximal tibia and the anterior wall of the artery.

Conclusions

The proximal branch group has a high risk for arterial injury as the artery may be close to the saw, and appropriate retraction should be performed.

Locomotive Syndrome and Lumbar Spine Disease: A Systematic Review

Locomotive syndrome (LS) is defined based on the Loco-Check, 25-question Geriatric Locomotive Function Scale (GLFS-25), 5-question Geriatric Locomotive Function Scale (GLFS-5), Stand-Up Test, Two-Step Test, or a total assessment (i.e., positive for one or more of the GLFS-25, Stand-Up Test, and Two-Step Test). Lumbar spine disease has been reported to be one of the most common musculoskeletal disorders leading to LS. We therefore conducted a systematic review via PubMed, Google Scholar, Cochrane Library, Web of Science, and MEDLINE, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 26 studies were considered to be eligible for inclusion in this systematic review. The GLFS-25 showed an association with low back pain, sagittal spinopelvic malalignment, and lumbar spinal stenosis but not vertebral fracture. The GLFS-5 showed an association with low back pain and lumbar spinal stenosis. The Loco-Check and Two-Step Test showed an association with low back pain, sagittal spinopelvic malalignment, and lumbar spinal stenosis. The Stand-Up Test showed no association with lumbar spinal stenosis. The total assessment showed an association with low back pain and lumbar spinal stenosis. Furthermore, the GLFS-25, Two-Step Test, and total assessment were improved by spinal surgery for lumbar spinal stenosis. The current evidence concerning the relationship between LS and lumbar spine disease still seems insufficient, so further investigations are required on this topic.

Artificial intelligence model to identify elderly patients with locomotive syndrome: A cross-section study

BACKGROUND

Identifying elderly individuals with locomotive syndrome is important to prevent disability in this population. Although screening tools for locomotive syndrome are available, these require time commitment and are limited by an individual's ability to complete questionnaires independently. To improve on this limitation, we developed a screening tool that uses information on the distribution of pressure on the plantar surface of the foot with an artificial intelligence (AI)-based decision system to identify patients with locomotor syndrome. Herein, we describe our AI-based system and evaluate its performance.

METHODS

This was a cross-sectional study of 409 participants (mean age, 73.5 years). A foot scan pressure system was used to record the planter pressure distribution during gait. In the image processing step, we developed a convolutional neural network (CNN) to return the logit of the probability of locomotive syndrome based on foot pressure images. In the logistic regression step of the AI model, we estimated the predictor coefficients, including age, sex, height, weight, and the output of the CNN, based on foot pressure images.

RESULTS

The AI model improved the identification of locomotive syndrome among elderly individuals compared to clinical data, with an area under curve of 0.84 (95% confidence interval, 0.79-0.88) for the AI model compared to 0.80 (95% confidence interval, 0.75-0.85) for the clinical model. Including the footprint force distribution image significantly improved the prediction algorithm (the net reclassification improvement was 0.675 [95% confidence interval, 0.45-0.90] P < 0.01; the integrated discrimination improvement was 0.059 [95% confidence interval, 0.039-0.088] P < 0.01).

CONCLUSIONS

The AI system, which includes force distribution over the plantar surface of the foot during gait, is an effective tool to screen for locomotive syndrome.

Differences in the prevalence of locomotive syndrome and osteoporosis in Japanese urban and rural regions: The Kashiwara and Yakumo studies

OBJECTIVES

To clarify whether the prevalence of locomotive syndrome (LS) and osteoporosis differed according to region, gender, and physical functions in Japan.

METHODS

Data were collected in Kashiwara City (urban region) and Yakumo Town (rural region). Totally, 208 participants from the urban region and 782 participants from the rural region were included in this study. LS was assessed using the 25-item Geriatric Locomotive Function Scale and osteoporosis was assessed using a quantitative ultrasound. Physical functions were measured using grip strength and the 3-m timed up-and-go test. Differences between urban and rural regions were investigated using standardized incidence ratio and multivariate analysis.

RESULTS

The prevalence of LS and osteoporosis was 24.5% and 42.8% in the urban region and 10.9% and 28.8% in the rural region, respectively. The standardized incidence ratio of the urban region versus the rural region was 1.80 (95% confidence intervals [CI] = 1.35-2.39) for LS and 1.21 (95% CI = 1.32-2.43) for osteoporosis, showing that the prevalence of LS was significantly higher in the urban region. Multivariate analysis indicated that LS was significantly associated with the urban sample and timed up-and-go was significantly longer in the urban sample.

CONCLUSION

Regional differences may be considered when evaluating LS in health checkups. Understanding the results of this study may help reduce LS prevalence.

ActiveHip+: A feasible mHealth system for the recovery of older adults after hip surgery during the COVID-19 pandemic

OBJECTIVE

Half of older adults undergoing hip surgery do not recover their previous functional status. mHealth is a promising tool for rehabilitating older adults after hip surgery. This study aimed to test the feasibility of the ActiveHip+ mHealth system in older adults after hip surgery.

METHODS

Sixty-nine older adults who had undergone hip surgery and their family caregivers were recruited from hospitals in Spain and Belgium and used the ActiveHip+ mHealth system for 12 weeks. Assessments were made during hospital stay and 3 months after surgery. Feasibility assessment included: adoption (participation proportion), usage (access to the app), satisfaction with the app (Net Promoter Score) and user perception of the quality of the app (Mobile App Rating Scale). Clinical assessment included: patient-reported outcomes, such as functional status (Functional Independence Measure) and performance-based outcomes, such as physical fitness (Short Physical Performance Battery).

RESULTS

The ActiveHip+ mHealth system obtained satisfactory feasibility results in both countries. In Spain, we observed 85% adoption, 64% usage, 8.86/10 in satisfaction with the app and 4.42/5 in perceived quality of the app. In Belgium, we observed 82% adoption, 84% usage, 5.16/10 in satisfaction with the app and 3.52/5 in app's perceived quality. The intervention had positive effects on levels of functional status, pain and physical fitness.

CONCLUSIONS

The ActiveHip+ mHealth system is a feasible tool to conduct the rehabilitation in older adults after hip surgery. Although the intervention seemed beneficial clinically, we do not recommend its implementation in clinical settings until appropriately designed randomised clinical trials confirm these results.

Prevalence of locomotive syndrome in Japanese patients more than 10 years after total hip arthroplasty: A cross-sectional cohort study

BACKGROUND

Locomotive syndrome (LS) is a high risk condition that requires nursing care. It is important to investigate the prevalence of and factors related to LS to maintain a healthy life expectancy for patients; however, only a few reports have focused on the relationship between LS and total hip arthroplasty (THA). The purpose of this study was to evaluate the prevalence of LS and to identify factors associated with LS in patients more than 10 years after THA.

METHODS

This is a cross-sectional cohort study. Patients were assessed via a mail survey that included items regarding demographic data, cardiometabolic and motor disorders, the incidence of falls, physical activity level, and the 25-question Geriatric Locomotive Function Scale (GLFS-25) questionnaire. LS was defined as having a score ≥16 on the GLFS-25, and the respondents were categorized into two groups: an LS group and a non-LS group. The prevalence of LS was calculated in each gender and age group. Differences in variables between the groups were determined using the unpaired t-test and chi-squared test.

RESULTS

A total of 593 patients were included in the study (mean age, 70.4 years; 525/593 females). According to the GLFS-25, 164 patients (27.7%; 21.1% men and 28.8% women) were classified as having LS, which increased with age. In addition, compared with the non-LS group, the LS group had a significantly higher prevalence of motor diseases, cardiometabolic diseases, and falls and significantly lower levels of activity.

CONCLUSION

These findings suggest that the prevalence of LS in patients more than 10 years after THA is 27.7%. The result suggest that the prevalence of LS in patients more than 10 years after THA is similar to the prevalence of LS in the general elderly population. Furthermore, LS is related to not only motor diseases but also cardiometabolic diseases.

Prevalence and associated factors of primary elbow osteoarthritis in the Japanese general elderly population: a Japanese cohort survey randomly sampled from a basic resident registry

BACKGROUND

The epidemiology of primary elbow osteoarthritis (PEOA) remains unknown. We aimed to evaluate the prevalence and associated factors of PEOA in a cross-sectional resident cohort from a municipal registry of a Japanese town.

METHODS

A total of 415 residents over 50 years of age were randomly sampled from a Japanese town and were adjusted for age and gender. Those with diseases that could potentially cause a secondary osteoarthritis of the elbow were excluded. The remaining 318 subjects (150 men and 168 women) underwent bidirectional radiography of the elbow. Subjects were diagnosed with PEOA if one of their elbows was Kellgren-Lawrence (KL) grade 2 or greater. In addition, motion pain and tenderness at the elbow were examined by orthopedic surgeons. Associated factors for the PEOA were statistically analyzed.

RESULTS

The prevalence of PEOA was 25.2% (male, 27.3%; female, 23.2%), and the prevalence of symptomatic PEOA was 0.9%. The age-stratified prevalence of PEOA was as follows: 50-59, 6.2% (male, 5.0%; female, 7.3%); 60-69, 15.4% (male, 17.5%; female, 13.7%); 70-79, 29.5% (male, 35.3%; female, 25.0%); and 80-89, 55.9% (male, 55.6%; female, 56.3%). Age and body mass index were revealed as associated factors that increased the prevalence of PEOA with KL grade 2 or greater. The use of vibrating tools was demonstrated as an independent associated factor that increased the prevalence of PEOA with KL grade 4 in addition to the 2 aforementioned factors.

CONCLUSIONS

The prevalence of PEOA in Japanese subjects was 25.2% for those aged 50-89 years with a mean age of 69.2 years, most of which was asymptomatic OA without motion pain or tenderness at the elbow. Age and body mass index increased the prevalence of PEOA with KL grade 2 or greater. The prevalence of PEOA increased with age, but the disease was self-accommodated by most people.

Prevalence of Locomotive Organ Impairment and Associated Factors among Middle-Aged and Older People in Nan Province, Thailand

While locomotive organ impairment among older people is attracting worldwide attention, this issue has not yet been widely investigated in Thailand. This study aimed to measure locomotive organ impairment prevalence and identify the determinants of locomotive function decline among middle-aged and older people in Nan Province, Thailand. This cross-sectional study included anthropometric measurements, a two-step test to investigate locomotive function, and a structured questionnaire to obtain socio-demographic and related information. Logistic regression analysis and multiple regression analysis were used to identify the determinants of locomotive organ impairment. The study participants were aged 50–87 years old (n = 165), and 71.5% of them had begun experiencing declining locomotive function; < 6 years of school education (adjusted odds ratio: 4.46), body mass index ≥25 kg/m² (AOR: 3.06), comorbidities (AOR: 2.55), and continuous walking for <15 min (AOR: 2.51) were identified as factors associated with locomotive organ impairment. Moreover, age, knee pain, anxiety about falling in daily life, and difficulty with simple tasks were identified as factors significantly associated with exacerbated locomotive organ impairment (p < 0.05). Appropriate interventions such as guidance or follow-up and recommendations for exercises are needed to prevent locomotive organ impairment and improve treatment.

Reciprocal relationship between locomotive syndrome and social frailty in older adults

AIM

States of vulnerability are multidimensional and become more prevalent with advancing age. These states and the causal relationships between them, merit thorough investigation. This study aimed to understand the reciprocal relationship between the constructs of the locomotive syndrome and social frailty among a community of older adults.

METHODS

This 2-year cohort study examined a community of older adults (≥75 years) consisting of 1177 members. Using Makizako's method, social frailty was deemed to be present if more than two out of five questions were answered negatively. Locomotive syndrome was measured with the Geriatric Locomotive Function Scale-25, which consists of 25 items measuring an individual's risk of developing locomotive syndrome; a total score of ≥16 identified the presence of locomotive syndrome. Possible reciprocal associations between locomotive syndrome and social frailty were assessed using Cox proportional hazards analyses.

RESULTS

A total of 748 older adults were analyzed in the following subgroups. Among 574 participants without social frailty at the baseline, the presence of locomotive syndrome at the baseline was associated with new-onset social frailty during the next 2 years, after adjusting for confounding factors (hazard ratio 1.76, 95% confidence interval 1.17-2.65). Conversely, the presence of social frailty among participants without locomotive syndrome in the baseline was not associated with new-onset locomotive syndrome.

CONCLUSION

The presence of locomotive syndrome was determined to be a risk factor for the onset of social frailty. Therefore, interventions that address the negative impact of locomotive syndrome are a first step toward addressing these vulnerable conditions. Geriatr Gerontol Int 2021; 21: 981-984.

Prevalence and physical characteristics of locomotive syndrome stages as classified by the new criteria 2020 in older Japanese people: results from the Nagahama study

Background

The Japanese Orthopaedic Association (JOA) proposed the concept of locomotive syndrome (LS) in 2007 for detecting high-risk individuals with mobility limitation. In 2020, the JOA revised the clinical decision limits and introduced LS stage 3, which carried the highest-risk for LS compared to the conventional stages, 1 and 2. The purpose of this study was to characterize the prevalence, comorbidities, and physical characteristics in each LS stage, as per the LS criteria 2020.

Methods

We analyzed 2077 participants (64.9% women; mean age, 68.3 ± 5.4 years) from the Nagahama Study aged ≥60 years. Participants were classified into 4 groups, non-LS and LS stages 1, 2, and 3, based on a 25-question Geriatric Locomotive Function Scale. The prevalence of comorbidities (sarcopenia, osteoporosis, diabetes mellitus, low back pain [LBP], and knee pain) were investigated. Physical characteristics were measured based on the physical performance tests including gait speed, five-times chair-stand, single-leg stand, and short physical performance battery; muscle strength tests including grip, knee extension, hip flexion, and abduction; and body-composition analysis including muscle quantity and quality. Differences in the prevalence of comorbidities between LS stages were tested using the chi-square test. The general linear model was performed for univariate and multivariate analyses with post-hoc test to compare the differences in physical characteristics among the LS stages.

Results

The prevalence of LS increased with age, and the mean prevalence of LS stages 1, 2, and 3 were 24.4, 5.5, and 6.5%, respectively. The prevalence of comorbidities, including sarcopenia, osteoporosis, LBP, and knee pain, increased with worsening LS stage. Physical performance tests were significantly different between LS stages 2 and 3; and muscle strength differed significantly between LS stages 1 and 2. Additionally, in terms of body composition analysis, muscle quality but not muscle quantity showed significant differences among all the LS stages.

Conclusions

Our findings suggest that muscle strengthening and dynamic training, including balance training in LS stage 1 and 2, respectively, were needed for preventing the LS progression. Individuals with LS stage 3 should perform dynamic training and muscle strengthening exercises while receiving treatment for comorbidities.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02440-2.

Differences of 2-year longitudinal changes of locomotive syndrome among patients treated with thoracolumbar interbody fusion, total hip arthroplasty, and total knee arthroplasty for degenerative diseases

OBJECTIVES

To clarify the longitudinal changes in patients with preoperative Stage-3 locomotive syndrome (LS) according to different types of surgeries, we investigated the changes in the LS stage in patients who underwent surgery for degenerative musculoskeletal diseases.

METHODS

A prospective cohort study was conducted on 168 patients with degenerative diseases [46 spinal deformities treated with thoracolumbar interbody fusion (T/LIF), 86 hips with osteoarthritis treated with total hip arthroplasty (THA), and 36 knees with osteoarthritis treated with total knee arthroplasty (TKA)]. The results for the LS stage, stand-up test, two-step test, and 25-question Geriatric Locomotive Function Scale (GLFS-25) were evaluated preoperatively and at 6 months, 1 year, and 2 years postoperatively.

RESULTS

Preoperatively, most patients had Stage-3 LS (89.1, 90.8, and 80.6% in the T/LIF, THA, and TKA groups, respectively). At 2 years postoperatively, the Stage-3 LS improved in 41.5, 75.6, and 55.2% of patients in the T/LIF, THA, and TKA groups, respectively. All groups showed similar improvements in the two-step test. The THA group showed the best result in the GLFS-25.

CONCLUSIONS

LS stage improved in different patterns over 2 years postoperatively and the LS risk test revealed differences in postoperative movement ability according to the type of surgery.

Evaluation of locomotive syndrome in patients receiving surgical treatment for degenerative musculoskeletal diseases: A multicentre prospective study using the new criteria

OBJECTIVES

This study aimed to evaluate the condition of patients with locomotive syndrome (LS) and their improvement after undergoing surgery for degenerative musculoskeletal diseases using the new criteria, including stage 3.

METHODS

In total, 435 patients aged ≥40 years (167 middle-aged and 268 older) were divided into four groups based on the disease location: the lumbar (n = 118), hip (n = 191), knee (n = 80), and foot and ankle (n = 46) groups. Patients were evaluated by pre- and 1 year postoperative LS risk tests, including the stand-up test, two-step test, and 25-Question Geriatric Locomotive Function Scale.

RESULTS

The pre- and postoperative prevalence of LS stage 3 were 78% and 29%, respectively. The postoperative LS stage improved in 62% of patients (77% and 53% in the middle-aged and older groups, respectively). Overall, the knee group showed the worst results, and the foot and ankle groups showed the best pre- and postoperative results. The pre- and postoperative prevalence of LS stage 3 according to the 25-Question Geriatric Locomotive Function Scale were comparable to those based on the total assessment.

CONCLUSIONS

The new LS stage criteria are appropriate, and the 25-Question Geriatric Locomotive Function Scale is a good option for evaluating patients requiring surgery.

Locomotive syndrome in hemodialysis patients and its association with quality of life—a cross-sectional study

Background

Locomotive syndrome (LS) is defined as impairment of mobility function.

This study aimed to clarify LS and its association with quality of life in hemodialysis patients.

Methods

This is a cross-sectional study. The subjects were chronic kidney disease patients undergoing maintenance hemodialysis treatment. LS was assessed using two physical tests (two-step test, stand-up test) and one self-reported test (Geriatric Locomotive Function Scale-25). LS has two stages of severity; the beginning of the decline in mobility function is known as Locomo stage 1, and the progression of the decline of mobility function is known as Locomo stage 2. We used SF-36 to assess quality of life and examined their relationships with the Locomo stages. Chi-square test, Kruskal-Wallis test, Jonckheere-Terpstra test, and Mantel-Haenszel test were used for analysis. Multiple linear regression was used to model the cross-sectional association of Locomo stages with each component and summary score of SF-36.

Results

A total of 76 hemodialysis patients were included. The number of subjects with Locomo stage 1 and stage 2 were 19 (25%) and 53 (70%), respectively, while only four (5%) subjects did not have mobility dysfunction. Each component and summary score of the SF-36 for physical function, role emotional, physical component summary, and mental component summary were significantly associated with Locomo stages.

Conclusion

A high prevalence and severity of LS in hemodialysis patients was found, and the severity was associated with quality of life.

Teeth loss and its association with locomotive syndrome among patients visiting the outpatient department of a dental school in Mahbubnagar, India-A cross sectional study

Background:

Locomotive syndrome (LoS) is condition wherein mobility functions such as sit-to-stand or gait are declined due to locomotive organ impairment. The important risk factors for the LoS are ageing and physical factors. Physical factors are significantly associated with dental status.

Aim:

To investigate the relationships between teeth lost and locomotive syndrome.

Materials and method:

A cross sectional study was conducted among (45-90 years) individuals by using Loco Check List. Factors related to demographics (age, sex) and number of teeth lost were assessed. Pearson’s chi-square test, multiple logistic regression analysis were performed. p <0.05 was considered to be statistically significant.

Results:

Out of 322 subjects, majority of subjects (58.7%) had LoS. Locomotive syndrome was observed high significantly (78.0% P = 0.0000) among >60 years age group. Majority of the subjects with tooth loss more than 10 teeth (92.6%) had a locomotive syndrome followed by the subjects with tooth loss 1-10 teeth (52.1%). Multiple logistic regression analysis revealed Locomotive syndrome was significantly (P= 0.000) higher among older age groups (>60 years) when compared with the 45- 60 years age group (or = 0.732) and subject with more than 10 teeth lost when compared with others (or = .009, or = 0.105)

Conclusion:

Study indicates that older age and number of teeth lost affect the prevalence of locomotive syndrome. Hence, maintaining oral health is necessary to retain more number of teeth throughout life which reduces the risk of locomotive syndrome. (www.actabiomedica.it)

Empirical study of the 30-s chair-stand test as an indicator for musculoskeletal disorder risk of sedentary behaviour in Japanese office workers: a cross-sectional empirical study

Objectives

Sedentary behaviour among office workers and the risk of adverse health outcomes are public health problems. However, risk indicators for these outcomes require invasive biochemical examination. A proactive screening tool using a non-invasive, easy-to-use method is required to assess the risk focused on musculoskeletal health for primary prevention. However, middle-aged adults have insufficient awareness of musculoskeletal disorders. This study examined to determine whether the 30-s chair-stand test (CS-30) can be used as a proactive screening index for musculoskeletal disorder risk of sedentary behaviour in office workers.

Design

Cross-sectional study using self-administered questionnaires and physical measurements.

Setting

Four workplaces located in a metropolitan area of Japan.

Participants

431 Japanese office workers aged 20–64 years. 406 valid sets of results remained (valid response rate: 94.2%).

Primary and secondary outcome measures

Musculoskeletal function was measured using the CS-30, quadriceps muscle strength. Receiver operating characteristic curve analysis was used to determine the sensitivity, specificity and optimal cut-off value for the CS-30. The risk of future incidence of musculoskeletal disorders was calculated using current quadriceps muscle strength.

Results

In total participants, 47.0% were male and the mean sitting time in work duration was 455.6 min/day (SD=111.2 min). The mean lower limb quadriceps muscle strength was 444.8 N (SD=131.3 N). For the optimum cut-off value of 23 on the CS-30 for all participants, sensitivity was 0.809 and specificity was 0.231. For men, the optimum cut-off was 25, with a sensitivity of 0.855 and a specificity 0.172. For women, the optimum cut-off was 21, with a sensitivity of 0.854 and a specificity 0.275.

Conclusions

Sensitivity was high, but specificity was insufficient. The CS-30 may be a potential proactive screening index for musculoskeletal disorder risk of sedentary behaviour, in combination with other indicators.

Long-Term Pain Management and Health Care Resource Use Among an Employed Population in Japan with Knee Osteoarthritis Combined with Low Back Pain

Objective

Assess long-term comorbidity burden and pain management patterns among working-age patients with knee osteoarthritis (KOA) only without low back pain (LBP) (KOA-noLBP) and patients with KOA plus LBP (KOA+LBP) in Japan.

Methods

Retrospective claims data analyses were conducted on data from the Japan Medical Data Center (JMDC) database. Adult patients (≥40 years) with a diagnosis of knee osteoarthritis (KOA) (January 1, 2011–December 31, 2012) and 5 years of follow-up were evaluated. The first claim with a KOA diagnosis defined the index date. Longitudinal pain management patterns were assessed in both cohorts.

Results

Overall, 1,828 patients met study criteria (717 with KOA-noLBP; 1,111 with KOA+LBP). The mean age of patients with KOA-noLBP was 52.1 years, and that of patients with KOA+LBP was 53.1 years, with more females in the KOA+LBP cohort (49.4% vs. 55.0%). Regardless of cohort, >90% of patients received pharmacological intervention during the 5-year follow-up period. The most common regimen first received was either topical or oral nonsteroidal anti-inflammatory drugs. A higher mean number of pharmaceutical treatments were received by patients in the KOA+LBP cohort (3.6) than by patients in the KOA-noLBP cohort (2.7) during the follow-up period. Regardless of cohort, most of the direct medical cost was derived from medication.

Conclusion

This study demonstrates that a greater proportion of the JMDC population of working individuals with KOA were comorbid with LBP and received pain-related treatment in the long-term perspective relative to patients with KOA without LBP. Appropriate pain management for both KOA and LBP would be key for effective resource utilization in an aging society facing socioeconomic burdens