Osteoporosis, spinal degenerative disorders, and their association with low back pain, activities of daily living, and physical performance in a general population.

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.

Prevalence and distribution of Schmorl node and endplate signal change, and correlation with disc degeneration in a population-based cohort: the Wakayama Spine Study.

PURPOSE: Degenerative spinal conditions, including disc degeneration (DD), Schmorl nodes (SN), and endplate signal changes (ESC), are pervasive age-associated phenomena that critically affect spinal health. Despite their prevalence, a comprehensive exploration of their distribution and correlations is lacking. This study examined the prevalence, distribution, and correlation of DD, SN, and ESC across the entire spine in a population-based cohort. METHODS: The Wakayama Spine Study included 975 participants (324 men, mean age 67.2 years; 651 women, mean age 66.0 years). Magnetic resonance imaging (MRI) was used to evaluate the intervertebral space from C2/3 to L5/S1. DD was classified using Pfirrmann's system, ESC was identified by diffuse high-intensity signal changes on the endplates, and SN was defined as a herniation pit with a hypointense signal. We assessed the prevalence and distribution of SN, ESC, and DD across the entire spine. The correlations among these factors were examined. RESULTS: Prevalence of ≥ 1 SN over the entire spine was 71% in men and 77% in women, while prevalence of ≥ 1 ESC was 57.9% in men and 56.3% in women. The prevalence of ESC and SN in the thoracic region was the highest among the three regions in both sexes. Positive linear correlations were observed between the number of SN and DD (r = 0.41, p < 0.001) and the number of ESC and DD (r = 0.40, p < 0.001), but weak correlations were found between the number of SN and ESC (r = 0.29, p < 0.001). CONCLUSION: The prevalence and distribution of SN and ESC over the entire spine were observed, and correlations between SN, ESC, and DD were established. This population-based cohort study provides a comprehensive analysis of these factors.

Endplate Deficits and Posterior Wall Injury Are Predictive of Prolonged Back Pain after Osteoporotic Vertebral Body Fracture.

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.

Psychological Predictors of Satisfaction after Lumbar Surgery for Lumbar Spinal Stenosis.

STUDY DESIGN: A retrospective study of prospectively collected clinical data. PURPOSE: To identify preoperative psychological factors associated with patient satisfaction after surgery for lumbar spinal stenosis (LSS). OVERVIEW OF LITERATURE: Associations between depressive symptoms, anxiety, and worse surgical outcome or patient dissatisfaction have been reported in LSS patients. However, the influence of preoperative pain catastrophizing and fear-avoidance beliefs on postoperative satisfaction is not well understood. METHODS: LSS patients who underwent decompression surgery with or without fusion were included. Clinical outcomes were measured before surgery and 6 months postoperatively using the Zurich Claudication Questionnaire (ZCQ); Visual Analog Scale (VAS) of low back pain, leg pain, and leg numbness; Japanese Orthopaedic Association Back Pain Evaluation Questionnaire; and the Medical Outcomes Study 36-item Short-Form General Health Survey (SF-36). The Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale, and Pain Anxiety Symptoms Scale were used to evaluate psychological status before surgery. Patients were classified as satisfied or dissatisfied with surgery based on a ZCQ satisfaction subscale cutoff score of 2.5. RESULTS: The satisfied and dissatisfied groups contained 128 and 29 patients, respectively. Six months postoperatively, outcome scores for the dissatisfied group were unchanged or worse than preoperative scores (p>0.05). Multivariate logistic regression analysis showed significant associations between dissatisfaction and preoperative low back pain VAS score ≥ median (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.10-0.74; p=0.01), preoperative mental health SF-36 score ≥ median (OR, 0.26; 95% CI, 0.08-0.89; p=0.03), and preoperative anxiety HADS score ≥ median (OR, 3.95; 95% CI, 1.16-13.46; p=0.03). CONCLUSIONS: Preoperative less severe low back pain, lower mental health, and higher anxiety are associated with patient dissatisfaction with lumbar surgery, not depression, pain catastrophizing, or fear-avoidance beliefs. Pre- and postoperative psychological status should be assessed carefully and managed appropriately.

Associations between psychological factors and daily step count in patients with lumbar spinal stenosis.

BACKGROUND: Body mass index, pain, female sex, and age have been reported as predictors of physical activity in patients with lumbar spinal stenosis (LSS). However, no reports have examined the psychological factors associated with physical activity in people with LSS. PURPOSE: To use psychological assessments to identify the factors associated with physical activity measured as daily step count in people with LSS. METHODS: Seventy-one patients who received outpatient physical therapy were included. All patients completed the following scales at baseline: Zurich Claudication Questionnaire; self-paced walking test (SPWT); numerical rating scale of low back pain, leg pain, and leg numbness; Hospital Anxiety and Depression Scale (HADS); Pain Catastrophizing Scale; Pain Anxiety Symptoms Scale (PASS-20); and Tampa Scale for Kinesiophobia. Physical activity was measured using a pedometer as the average number of daily steps. RESULTS: Daily step count was significantly associated with age, number of stenoses, severity of stenosis at L3-L4, walking distance on the SPWT, PASS-20 total score, cognitive anxiety, escape/avoidance, fear, and HADS depression score (p < .05). Multiple regression analysis showed that age, severity of stenosis at L3-L4, walking distance on the SPWT, and PASS-20 fear predicted daily step count (r2 = 0.414). CONCLUSION: Older age, fewer stenoses, less severe stenosis at L3-L4, lower walking capacity, higher anxiety, and fear-avoidance beliefs about pain and depression are more closely associated with lower daily step count than are back and leg pain. Assessment and treatment of psychological factors might help to increase physical activity in patients with LSS.

Supervised physical therapy versus unsupervised exercise for patients with lumbar spinal stenosis: 1-year follow-up of a randomized controlled trial.

OBJECTIVE: To compare the 1-year outcomes of patients with lumbar spinal stenosis treated with supervised physical therapy or unsupervised exercise. DESIGN: A single-center randomized controlled trial with concealed allocation, blinded assessor and intention-to-treat analysis. SETTING: Spine care center. SUBJECTS: A total of 86 patients presenting with symptoms of neurogenic claudication caused by lumbar spinal stenosis. INTERVENTIONS: The physical therapy group received supervised physical therapy sessions twice a week for 6 weeks and home exercise program. The home exercise group received 6-week home exercise program only. MAIN MEASURES: The primary outcome was symptom severity on the Zurich claudication questionnaire at 1 year. Secondary outcomes included physical function, pain, health-related quality of life and the surgery rate after 1 year. RESULTS: At 1 year, more patients in the physical therapy group than in the home exercise group achieved minimum clinically important differences in Zurich claudication questionnaire symptom severity (60.5% vs 32.6%; adjusted odds ratio [AOR] 4.3, [95% CI [1.5-12.3], P = 0.01); Zurich claudication questionnaire physical function (55.8% vs 32.6%; AOR 3.0 [1.1-8.1], P = 0.03); SF-36 bodily pain (48.8% vs 25.6%; AOR 2.8 [1.1-7.3], P = 0.03), and SF-36 general health (20.9% vs 7.0%; AOR 6.1 [1.1-33.0], P = 0.04). The surgery rate at 1 year was lower in the physical therapy than in the home exercise group (7.0% vs 23.3%; AOR 0.2 [0.04-0.9] P = 0.04). CONCLUSIONS: Supervised physical therapy produced greater improvements in symptom severity and physical function than unsupervised exercise and was associated with lower likelihood of receiving surgery within 1 year.

Influence of Sarcopenia on the Effect of Exercise Therapy for Elderly Patients with Chronic Low Back Pain.

INTRODUCTION: Sarcopenia, a condition characterized by decreased skeletal muscle mass, has increasingly been attracting attention in Japan, which has an aged society. The association between chronic low back pain (CLBP) and muscle mass is important. This study aimed to investigate the effect of exercise therapy for CLBP with or without sarcopenia. METHODS: This study was a prospective cohort study. Patients who were aged >65 years during 2017-2018 and had CLBP, with pain lasting >12 weeks and pain intensity being ≥3, were included in the study. The patients were divided into two groups: sarcopenia (S) and nonsarcopenia (NS) groups. The numerical rating scale (NRS) for pain intensity, Roland-Morris Disability Questionnaire (RMDQ), Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), Hospital Anxiety and Depression Scale (HADS), trunk muscle strength, a European Quality of Life instrument, and an NRS of treatment satisfaction were assessed. All patients underwent a high-intensity exercise therapy during 2 weeks of hospitalization and were followed up for 1 and 3 months. RESULTS: Twenty-eight patients with CLBP were included. The prevalence rate of sarcopenia was 42.9%. The NRS and RMDQ scores and gait function were clinically improved at the end points in all patients with or without sarcopenia. Moreover, high treatment satisfaction was achieved. The quality of life, treatment satisfaction, psychological disorder subscale score of the JOABPEQ, and HADS score tended to be lower in the S group than in the NS group. CONCLUSIONS: Our short-term exercise therapy was effective for low back pain, disability, and gait disturbance in elderly patients with CLBP with or without sarcopenia. However, the prevalence of sarcopenia was high in elderly patients with CLBP. Although low back pain and disability in patients in the S group were improved by exercise therapy, their quality of life and treatment satisfaction might be lower than those of patients without sarcopenia.

Clinical Features of Sarcopenia in Patients With Lumbar Spinal Stenosis.

STUDY DESIGN: Cross-sectional design. OBJECTIVE: To investigate the prevalence of sarcopenia and identify factors associated with sarcopenia in patients with lumbar spinal stenosis (LSS). SUMMARY OF BACKGROUND DATA: Patients with LSS have a higher prevalence of sarcopenia compared with healthy older adults. However, the clinical features of sarcopenia in patients with LSS are poorly understood and the factors affecting sarcopenia in patients with LSS remain unclear. METHODS: Patients diagnosed with LSS based on clinical examination and magnetic resonance imaging findings, and referred to physical therapy, were enrolled. Muscle mass was measured using bioelectrical impedance using InBody S10. We collected a numerical rating scale (NRS) for back pain, the 36-Item Short-Form Survey (SF-36), the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), bone mineral density (BMD), and radiographic measurements of spinal alignment. Sarcopenia was defined according to the Asian Working Group for Sarcopenia guidelines and patients were classified into sarcopenia or nonsarcopenia groups. RESULTS: A total of 178 patients were enrolled: 35 in the sarcopenia group and 143 in the nonsarcopenia group. The prevalence of sarcopenia was 19.7%. The average percent of slip (% slip) among patients in the sarcopenia group was significantly higher compared with those in the nonsarcopenia group (P < 0.05). Body mass index (BMI), BMD, physical function as assessed by the SF-36, and gait disturbance as assessed by the JOABPEQ were significantly lower in the sarcopenia group compared with those in the nonsarcopenia group (P < 0.05). A trend was observed toward between-group differences in back pain on the NRS (P < 0.1). In the logistic regression analysis, significant associations were seen between sarcopenia and % slip (odds ratio 1.15, 95% CI 1.01-1.30). CONCLUSION: Patients with LSS and sarcopenia have a higher degree of slippage and lower BMI, BMD, and physical function, and reported more severe low back pain, compared with those without sarcopenia. LEVEL OF EVIDENCE: 4.

Therapeutic Advantages of Frequent Physical Therapy Sessions for Patients With Lumbar Spinal Stenosis.

STUDY DESIGN: A retrospective study of a randomized clinical trial and a prospective study of patients with lumbar spinal stenosis (LSS). OBJECTIVE: The aim of this study was to identify the effects of the number of physical therapy (PT) sessions on clinical outcomes of patients with LSS. SUMMARY OF BACKGROUND DATA: Supervised PT for patients with LSS has been reported to lead to better short-term outcomes in terms of disability and leg pain than unsupervised exercise. However, no studies have investigated the relationship between the number of PT sessions and the therapeutic effects in patients with LSS. METHODS: All patients received exercise therapy for 6 weeks. Included were 43 patients receiving supervised PT twice a week (P2 group), 38 patients receiving supervised PT once a week (P1 group), and 43 patients receiving a home exercise program alone (HE group). Clinical outcomes were measured using the Zurich Claudication Questionnaire (ZCQ), a numerical rating scale (NRS) of back pain and leg pain, the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) at baseline and at 6 weeks. RESULTS: At 6 weeks, the P2 group showed significant improvements in ZCQ physical function, back and leg pain on the NRS compared with the P1 group (P < 0.05). Compared with the HE group, the P2 group showed significant improvements in ZCQ symptom severity and physical function, back and leg pain on the NRS, and JOABPEQ gait disturbance (P < 0.05). There were no significant differences in mean changes after 6 weeks between the P1 and HE groups. CONCLUSION: Six weeks of supervised PT twice a week resulted in significant short-term improvements in symptom severity, physical function, back and leg pain, and gait disturbance compared with once a week and/or home exercise alone. Patients with LSS should be treated with intensive and supervised exercise programs to obtain maximum benefit of exercise therapy. LEVEL OF EVIDENCE: 3.

Supervised physical therapy vs. home exercise for patients with lumbar spinal stenosis: a randomized controlled trial.

BACKGROUND CONTEXT: Exercise has been reported to improve short-term outcomes for patients with LSS in terms of disability and back and leg pain. However, no studies have compared supervised exercise with unsupervised exercise or quantified physical activity using a pedometer to confirm compliance with a home exercise program. PURPOSE: To compare the effectiveness of supervised physical therapy (PT) with unsupervised exercise for patients with lumbar spinal stenosis (LSS). STUDY DESIGN/SETTING: A single-center, open-label, randomized controlled trial. PATIENT SAMPLE: Patients presenting with symptoms of neurogenic claudication caused by LSS, which was confirmed by magnetic resonance imaging. OUTCOME MEASURES: The primary outcome was improvement in symptom severity scores on the Zurich Claudication Questionnaire (ZCQ) at 6 weeks. Secondary outcomes included physical function on the ZCQ, self-paced walking test (SPWT) performance, pain indicated using a numerical rating scale (NRS), and the number of daily steps measured by pedometer. METHODS: Patients with LSS were randomized to a PT group, who performed supervised PT twice a week for 6 weeks, or a home exercise (HE) group. PT sessions included manual therapy, individually tailored stretching and strengthening exercises, cycling, and body weight-supported treadmill walking. RESULTS: Forty-three patients were randomly allocated to the PT group and 43 patients to the HE group. Compared with the HE group, the PT group had greater percentage of responders achieving minimum clinically important difference in ZCQ symptom severity (difference for percentage between groups [95%confidence interval], 30.2% [9.1-48.6], p=.01), ZCQ physical function (32.6% [11.6-50.6], p<.01), walking distance on the SPWT (39.5% [18.8-56.7], p<.01), leg pain on the NRS (34.9% [13.9-52.7], p<.01), and number of daily steps (25.6% [4.9-43.9], p=.01). CONCLUSIONS: Supervised PT for patients with LSS resulted in significant short-term improvements in symptom severity, physical function, walking distance, pain, and physical activity compared with unsupervised exercise.

Prevalence of Facet Effusion and Its Relationship with Lumbar Spondylolisthesis and Low Back Pain: The Wakayama Spine Study.

INTRODUCTION: Facet effusion represents a magnetic resonance imaging finding suggesting accumulation of fluid in the facet joint, potentially predictive of lumbar spondylolisthesis and low back pain. However, its prevalence and epidemiological characteristics in the general population remain unclear, because previous studies only included patients or volunteers. The aim of the present study was to investigate the prevalence of facet effusion in the general population and to describe its potential relationship with spondylolisthesis and low back pain. MATERIAL AND METHODS: Our study enrolled 808 participants from the Wakayama Spine Study who underwent magnetic resonance imaging investigations in supine position. Facet effusion was defined as a measurable, curvilinear, high-intensity signal within the facet joint, closely matching that of cerebrospinal fluid on the axial T2 images. We used standing lateral radiographs to diagnose L4 spondylolisthesis. RESULTS: We found that the prevalence of facet effusion in the lumbar spine was 34.3%, which did not differ significantly between men and women (p=0.13) and did not tend to increase with age, either in men (p=0.81) or in women (p=0.65). Additionally, we found no significant association between facet effusion and low back pain (odds ratio, 1.04-1.49; 95% confidence interval, 0.57-2.64; p=0.17-0.85), or between facet effusion and L4 spondylolisthesis (odds ratio, 1.55; 95% confidence interval, 0.80-2.86; p=0.17). In a subset of participants with L4 spondylolisthesis, we also noted that facet effusion was not significantly associated with low back pain (odds ratio, 1.26; 95% confidence interval, 0.37-4.27; p=0.70). DISCUSSION: This is the first study of facet effusion employing a population-based cohort, and the findings are thus expected to accurately describe the relationship between facet effusion and low back pain in the general population. We are planning a follow-up survey of the Wakayama Spine Study cohort to clarify the natural history of facet effusion and its relationship with clinical symptoms.

A comparative study of gait characteristics associated with and without degenerative lumbar spondylolisthesis in patients with lumbar spinal stenosis.

BACKGROUND: Reported characteristics of DS include forward slippage of the superior lumbar relative to the inferior lumbar, lumbar instability, increased lumbar lordotic angle, and high body mass index (BMI). However, to our knowledge, only static measurements were conducted in previous studies, and no dynamic observations exist. In this crosssectional study, the gait of patients with and without DS in LSS was compared, and their characteristics were examined using a three-dimensional motion analysis system. METHODS: In total, 42 patients with LSS were included. Lumbar lordosis angle, sacral tilt angle, lumbar slip rate determined from X-ray images, the Zurich Claudication Questionnaire (ZCQ), the visual analog scale (VAS), and BMI were evaluated. U-COM length was the distance between the upper center of mass (COM) and the body's COM, while L-COM length was the distance between the lower COM and the COM. Each DS and Non-DS group evaluation was compared using the Mann-Whitney U-test. Additionally, multivariate analysis was performed using factors with significant differences as explanatory variables and with or without DS as the target variable. RESULTS: Lumbar lordotic angle was significantly higher in the DS group and there was a significant difference between U-COM and L-COM lengths in the sagittal planes at heel contact (HC) and toe-off (TO). L-COM length at HC and TO was a significant variable when the lumbar lordotic angle was adjusted as a confounding factor in multivariate analysis. CONCLUSIONS: The U-COM and L-COM lengths in the DS group were both extended and the line connecting each COM was inclined backward on the sagittal plane at HC and TO during gait. Our study showed that L-COM length was associated with or without DS.

Diffuse idiopathic skeletal hyperostosis is associated with lumbar spinal stenosis requiring surgery.

Factors related to the onset and progression of lumbar spinal stenosis (LSS) have not yet been identified. Diffuse idiopathic skeletal hyperostosis (DISH) increases mechanical loading on the non-fused lumbar levels and may therefore lead to LSS. This cross-sectional study aimed to identify associations between LSS and DISH. This study included 2363 consecutive patients undergoing surgery for LSS and 787 general inhabitants without symptoms of LSS as participants of the population-based cohort study, Research on Osteoarthritis/Osteoporosis Against Disability. Standing whole-spine radiographs were used to diagnose DISH based on the criteria proposed by Resnick and Niwayama. The prevalence of DISH showed a significant step-wise increase among asymptomatic inhabitants without radiographic LSS, asymptomatic inhabitants with radiographic LSS, and patients with LSS requiring surgery (14.4, 21.1, and 31.7%, respectively; p < 0.001). The distribution of DISH was similar between the groups, but the lower thoracic and upper-middle lumbar spine regions were more frequently involved in patients with LSS requiring surgery. Multivariate analysis indicated that DISH was an independent associated factor for LSS requiring surgery (adjusted odds ratio 1.65; 95% confidence interval 1.32-2.07) after adjustment for age, sex, body mass index, and diabetes mellitus. Among patients with LSS requiring surgery, a higher occurrence of stenosis at the upper lumbar levels and multi-level stenosis were observed in patients with DISH requiring surgery than in patients without DISH. In conclusion, DISH is independently associated with LSS requiring surgery. The decrease in the lower mobile segments by DISH may increase the onset or severity of LSS.

Serum levels of matrix metalloproteinase-3 and autoantibodies related to rheumatoid arthritis in the general Japanese population and their association with osteoporosis and osteoarthritis: the ROAD study.

To purpose of this study was to reveal the mean levels and positive proportion of serological markers related to rheumatoid arthritis, and clarify their relationship with osteoporosis and hand osteoarthritis (OA). A total of 1546 participants from the third survey of the research on osteoarthritis/osteoporosis against disability study were enrolled in the current study. Using participant blood samples, the levels of anti-cyclic citrullinated protein (CCP) antibody, rheumatoid factor (RF), matrix metalloproteinase-3 (MMP-3), C-reactive protein (CRP), and high-sensitivity CRP (hsCRP) were measured. Subjects with higher than normal levels were defined as being positive. Osteoporosis was defined according to the recommendations set by World Health Organization criteria in 1994. Radiographic hand OA was evaluated using the modified Kellgren-Lawrence (KL) scale. The positive proportion of anti-CCP antibody, RF, MMP-3, CRP, and hsCRP was 1.8, 7.1, 15.0, 6.7, and 6.4%, respectively. MMP-3 was associated with age, and was significantly higher in men than in women. Positive MMP-3 was not significantly related to osteoporosis or severe hand OA (KL grade ≥3) after adjustment for other factors including age, sex, and body mass index. The results from this study clarified the values and positive proportion of RA-related markers and revealed their relationship with osteoporosis and hand OA.

MRI-defined paraspinal muscle morphology in Japanese population: The Wakayama Spine Study.

OBJECTIVE: This study aimed to establish sex- and age-dependent distributions of the cross sectional area and fatty infiltration ratio of paraspinal muscles, and to examine the correlation between paraspinal muscle degeneration and low back pain in the Japanese population. METHODS: In this cross-sectional study, data from 796 participants (241 men, 555 women; mean age, 63.5 years) were analyzed. The measurement of the cross sectional area and fatty infiltration ratio of the erector spinae and multifidus from the level of T12/L1 to L4/5 and psoas major at the level of T12/L1 was performed using axial T2-weighted magnetic resonance imaging. Multivariate logistic regression analysis was used to estimate the association between fatty infiltration of the paraspinal muscles and the prevalence of low back pain. RESULTS: The cross sectional area was larger in men than women, and tended to decrease with age, with the exception of the erector spinae at T12/L1 and L1/2 in women. The fatty infiltration ratio was lower in men than women, except for multifidus at T12/L1 in 70-79 year-olds and psoas major in those less than 50 years-old, and tended to increase with age. Logistic regression analysis adjusted for age, sex, and body mass index showed that the fatty infiltration ratio of the erector spinae at L1/2 and L2/3 was significantly associated with low back pain (L1/2 level: odds ratio, 1.05; 95% confidence interval, 1.005-1.104; L2/3 level: odds ratio, 1.05; 95% confidence interval, 1.001-1.113). CONCLUSION: This study measured the cross sectional area and fatty infiltration ratio of paraspinal muscles in the Japanese population using magnetic resonance imaging, and demonstrated that the fatty infiltration ratio of the erector spinae in the upper lumbar spine was significantly associated with the presence of low back pain. The measurements could be used as reference values, which are important for future comparative studies.

Minimally invasive decompression surgery for lumbar spinal stenosis with degenerative scoliosis: Predictive factors of radiographic and clinical outcomes.

There is ongoing controversy regarding the most appropriate surgical treatment for lumbar spinal stenosis (LSS) with concurrent degenerative lumbar scoliosis (DLS): decompression alone, decompression with limited spinal fusion, or long spinal fusion for deformity correction. The coexistence of degenerative stenosis and deformity is a common scenario; Nonetheless, selecting the appropriate surgical intervention requires thorough understanding of the patients clinical symptomatology as well as radiographic parameters. Minimally invasive (MIS) decompression surgery was performed for LSS patients with DLS. The aims of this study were (1) to investigate the clinical outcomes of MIS decompression surgery in LSS patients with DLS, and (2) to identify the predictive factors for both radiographic and clinical outcomes after MIS surgery. 438 consecutive patients were enrolled in this study. Inclusion criteria was evidence of LSS and DLS with coronal curvature measuring greater than 10°. The Japanese Orthopaedic Association (JOA) score, JOA recovery rate, low back pain (LBP), and radiographic features were evaluated preoperatively and at over 2 years postoperatively. Of the 438 patients, 122 were included in final analysis, with a mean follow-up of 2.4 years. The JOA recovery rate was 47.6%. LBP was significantly improved at final follow-up. Cobb angle was maintained for 2 years postoperatively (p = 0.159). Clinical outcomes in foraminal stenosis patients were significantly related to sex, preoperative high Cobb angle and progression of scoliosis (p = 0.008). In the severe scoliosis patients, the JOA recovery was 44%, and was significantly depended on progression of scoliosis (Cobb angle: preoperation 29.6°, 2-years follow-up 36.9°) and mismatch between the pelvic incidence (PI) and the lumbar lordosis (LL) (preoperative PI-LL 35.5 ± 21.2°) (p = 0.028). This study investigated clinical outcomes of MIS decompression surgery in LSS patients with DLS. The predictive risk factors of clinical outcomes were severe scoliosis, foramina stenosis, progressive scoliosis and large mismatch of PI-LL.

Classification of High Intensity Zones of the Lumbar Spine and Their Association with Other Spinal MRI Phenotypes: The Wakayama Spine Study.

INTRODUCTION: High intensity zones (HIZ) of the lumbar spine are a phenotype of the intervertebral disc noted on MRI whose clinical relevance has been debated. Traditionally, T2-weighted (T2W) magnetic resonance imaging (MRI) has been utilized to identify HIZ of lumbar discs. However, controversy exists with regards to HIZ morphology, topography, and association with other MRI spinal phenotypes. Moreover, classification of HIZ has not been thoroughly defined in the past and the use of additional imaging parameters (e.g. T1W MRI) to assist in defining this phenotype has not been addressed. MATERIALS AND METHODS: A cross-sectional study of 814 (69.8% females) subjects with mean age of 63.6 years from a homogenous Japanese population was performed. T2W and T1W sagittal 1.5T MRI was obtained on all subjects to assess HIZ from L1-S1. We created a morphological and topographical HIZ classification based on disc level, shape type (round, fissure, vertical, rim, and enlarged), location within the disc (posterior, anterior), and signal type on T1W MRI (low, high and iso intensity) in comparison to the typical high intensity on T2W MRI. RESULTS: HIZ was noted in 38.0% of subjects. Of these, the prevalence of posterior, anterior, and both posterior/anterior HIZ in the overall lumbar spine were 47.3%, 42.4%, and 10.4%, respectively. Posterior HIZ was most common, occurring at L4/5 (32.5%) and L5/S1 (47.0%), whereas anterior HIZ was most common at L3/4 (41.8%). T1W iso-intensity type of HIZ was most prevalent (71.8%), followed by T1W high-intensity (21.4%) and T1W low-intensity (6.8%). Of all discs, round types were most prevalent (anterior: 3.6%, posterior: 3.7%) followed by vertical type (posterior: 1.6%). At all affected levels, there was a significant association between HIZ and disc degeneration, disc bulge/protrusion and Modic type II (p<0.01). Posterior HIZ and T1W high-intensity type of HIZ were significantly associated with disc bulge/protrusion and disc degeneration (p<0.01). In addition, posterior HIZ was significantly associated with Modic type II and III. T1W low-intensity type of HIZ was significantly associated with Modic type II. CONCLUSIONS: This is the first large-scale study reporting a novel classification scheme of HIZ of the lumbar spine. This study is the first that has utilized T2W and T1W MRIs in differentiating HIZ sub-phenotypes. Specific HIZ sub-phenotypes were found to be more associated with specific MRI degenerative changes. With a more detailed description of the HIZ phenotype, this scheme can be standardized for future clinical and research initiatives.

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

OBJECTIVE: The purpose of this study was to evaluate the relations between the degree of encroachment, measured as the cross-sectional area of the dural sac, and low back pain in a large population. METHODS: In this cross-sectional study, data from 802 participants (247 men, 555 women; mean age, 63.5 years) were analyzed. The measurement of the cross-sectional area of the dural sac from the level of L1/2 to L4/5 was taken using axial T2-weighted images. The minimum cross-sectional area was defined as the cross-sectional area of the dural sac at the most constricted level in the examined spine. Participants were divided into three groups according to minimum cross-sectional area measurement quartiles (less than the first quartile, between the first and third quartiles, and greater than the third quartile). A multivariate logistic regression analysis was used to estimate the association between the minimum cross-sectional area and the prevalence of low back pain. RESULTS: The mean minimum cross-sectional area was 117.3 mm2 (men: 114.4 mm2; women: 118.6 mm2). A logistic regression analysis adjusted for age, sex, body mass index, and other confounding factors, including disc degeneration, showed that a narrow minimum cross-sectional area (smaller than the first quartile) was significantly associated with low back pain (odds ratio, 1.78; 95% confidence interval, 1.13-2.80 compared to the wide minimum cross-sectional area group: minimum cross-sectional area greater than the third quartile measured). CONCLUSION: This study showed that a narrow dural sac cross-sectional area was significantly associated with the presence of low back pain after adjustment for age, sex, and body mass index. Further investigations that include additional radiographic findings and psychological factors will continue to elucidate the causes of low back pain.

Prevalence of hand osteoarthritis and its relationship to hand pain and grip strength in Japan: The third survey of the ROAD study.

OBJECTIVES: To examine the prevalence and pattern of hand osteoarthritis (HOA), and determine its relationship with grip strength and hand pain. METHODS: Among the participants of the third survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study, 507 Japanese men and 1028 Japanese women were included. Radiographs of both hands were graded for osteoarthritis (OA) using the modified Kellgren-Lawrence (KL) scale. HOA was defined as the presence of at least one affected joint. The absence or presence of subchondral erosion was also scored. RESULTS: The prevalence of HOA (KL grade ≥2) was 89.9% in men and 92.3% in women (p = 0.11), and it was significantly associated with age. OA in the distal interphalangeal (DIP) joint was the highest overall. After adjusting for age, sex, body mass index, and the residing area, both severity (KL grade ≥3) and erosion were significantly related to low grip strength and hand pain. With regard to the joint groups, severe OA in the DIP and first carpometacarpal joints were related to hand pain. CONCLUSION: This study showed a high prevalence of radiographic HOA and a significant relationship between hand pain and the severity of HOA, in addition to erosion.

Metabolic Syndrome Components Are Associated with Intervertebral Disc Degeneration: The Wakayama Spine Study.

OBJECTIVE: The objective of the present study was to examine the associations between metabolic syndrome (MS) components, such as overweight (OW), hypertension (HT), dyslipidemia (DL), and impaired glucose tolerance (IGT), and intervertebral disc degeneration (DD). DESIGN: The present study included 928 participants (308 men, 620 women) of the 1,011 participants in the Wakayama Spine Study. DD on magnetic resonance imaging was classified according to the Pfirrmann system. OW, HT, DL, and IGT were assessed using the criteria of the Examination Committee of Criteria for MS in Japan. RESULTS: Multivariable logistic regression analysis revealed that OW was significantly associated with cervical, thoracic, and lumbar DD (cervical: odds ratio [OR], 1.28; 95% confidence interval [CI], 0.92-1.78; thoracic: OR, 1.75; 95% CI, 1.24-2.51; lumbar: OR, 1.87; 95% CI, 1.06-3.48). HT and IGT were significantly associated with thoracic DD (HT: OR, 1.54; 95% CI, 1.09-2.18; IGT: OR, 1.65; 95% CI, 1.12-2.48). Furthermore, subjects with 1 or more MS components had a higher OR for thoracic DD compared with those without MS components (vs. no component; 1 component: OR, 1.58; 95% CI, 1.03-2.42; 2 components: OR, 2.60; 95% CI, 1.62-4.20; ≥3 components: OR, 2.62; 95% CI, 1.42-5.00). CONCLUSION: MS components were significantly associated with thoracic DD. Furthermore, accumulation of MS components significantly increased the OR for thoracic DD. These findings support the need for further studies of the effects of metabolic abnormality on DD.