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BACKGROUND: Knee osteoarthritis (OA) impairs postural control and may affect how the lower limb joints are used for postural control. OBJECTIVE: To investigate how individuals with knee OA use lower limb joints for static postural control. METHODS: Ten patients with knee OA and thirteen healthy controls performed quiet standing for 30 s. The standard deviation of the center of mass (COM) and lower limb joint motions in the anterior-posterior (AP) and medial-lateral (ML) planes were calculated from three-dimensional marker trajectories. Pearson’s correlation analysis and independent t-tests were conducted to investigate the relationship between COM and lower limb joint motion and to compare group difference, respectively. RESULTS: The AP hip angular velocity alone in the knee OA group and the AP hip and knee angular velocity in the control group were significantly correlated with the AP COM velocity. The ML hip angular velocity was significantly correlated with the ML COM velocity in both groups. The knee OA group exhibited a significantly larger standard deviation of AP COM velocity than the control group. CONCLUSIONS: Individuals with knee OA depended solely on the contribution of the hip to the AP COM velocity, which could not be successfully controlled by the knee.

Background: Associations between attention-deficit/hyperactivity disorder (ADHD) and chronic pain disorders, such as fibromyalgia, have been reported. However, associations between persistent chronic nonspecific low back pain (CNLBP) and ADHD have not yet been investigated. Objectives: This study aimed to investigate the positive rates of possible ADHD, as assessed by selfreported ADHD scales, in patients with persistent CNLBP, using data from self-reported questionnaires completed by patients and their families. This study also aimed to compare the self-reported scores obtained from existing standardized data for healthy individuals, and to examine whether the ADHD scale scores of patients with persistent CNLBP are associated with pain variables. Study Design: Cross-sectional study. Setting: The specialized pain clinic at our university hospital. Methods: This cross-sectional study included 60 consecutive patients with persistent CNLBP who were diagnosed with a possible somatic symptom disorder and were referred to a psychiatrist in our pain clinic. The Conners’ Adult ADHD Rating Scales (CAARS) self-report (CAARS-S) and observer-rated (CAARS-O) questionnaires were utilized. We investigated the CAARS scores, and the association between the CAARS subscale scores and pain variables (pain duration and pain Numeric Rating Scale) in patients with persistent CNLBP. Results: Of the 60 patients, 19 (31.7%) were positive on both CAARS-S and CAARS-O questionnaires (T-score > 65). The ADHD indices, which comprised subscales of the CAARS estimating the necessity of treatment for ADHD, were significantly higher in both male and female patients with persistent CNLBP than in the Japanese standardized sample (P < 0.005). CAARS-S hyperactivity/restlessness, CAARS-O hyperactivity/restlessness, and the Diagnostic and Statistical Manual of Mental Disorders, fourth edition hyperactive-impulsive symptom subscale scores also correlated with the pain intensity (P < 0.05). Limitations: In this study, ADHD tendency was evaluated using only a self-reported questionnaire. Hence in the future, accurate and precise assessments of ADHD symptoms using structured clinical interviews conducted by ADHD experts are warranted. Additionally, the study only included patients with persistent CNLBP. Therefore in the future, it will be valuable to investigate ADHD scale scores (e.g., CAARS) among patients with CNLBP and nonspecific low back pain with larger sample sizes. Conclusions: Our findings revealed that the subscale scores on an ADHD scale were considerably high in patients with persistent CNLBP. As a previous study of our clinical experience indicates that persistent CNLBP can be substantially relieved by administering ADHD medications, ADHD screening is warranted in the treatment of persistent CNLBP. Key words: Attention-deficit/hyperactivity disorder, neurodevelopmental disorders, chronic nonspecific low back pain, chronic pain, Conners’ Adult ADHD Rating Scales (CAARS), Numeric Rating Scale, pain duration, pain clinic, somatic symptom disorder

Objectives: To investigate the effects of pelvic and trunk lateral tilt-focused landing instructions on the knee abduction moment during the single-leg drop vertical jump task. Design: Descriptive laboratory study. Setting: Motion analysis laboratory. Participants: Fifteen young, healthy female participants. Main outcome measures: The participants performed 15 single-leg drop vertical jumps. Landing in-structions with self-video recordings were provided so that the participants' pelvis and trunk remained horizontal in the frontal plane. Pelvic, trunk and knee kinematics and kinetics were evaluated using a three-dimensional motion analysis system before and after the landing instructions. Results: The peak knee abduction moment significantly decreased postinstruction (preinstruction 22.6 +/- 15.3 Nm, postinstruction 17.9 +/- 15.4 Nm, P = 0.004), as did pelvic and trunk lateral tilt (P < 0.01). The knee abduction and internal rotation angles at initial contact significantly decreased postinstruction (P = 0.037, P = 0.007), with no significant change in the peak knee abduction and internal rotation angles from pre-to postinstruction. Conclusions: Landing instructions focused on pelvic and trunk lateral tilt are effective in decreasing the knee abduction moment during the single-leg drop vertical jump. Pelvic and trunk lateral tilt should be controlled to decrease the knee abduction moment during single-leg landing.

Background Abdominal draw-in maneuver (ADIM) has been recommended to achieve appropriate trunk muscle response for patients with non-specific chronic low back pain (CLBP). However, it has remained unclear whether the intervention with ADIM could change the trunk muscle response to sudden release from loading, which is considered to contribute mechanical circumstances to low back pain. The purpose of the present study was to investigate the effects of the intervention with ADIM on electromyography (EMG) activities of trunk muscles following sudden release from loading. Methods Seventeen subjects with non-specific CLBP participated. Subjects resisted trunk flexion or extension loading in semi-seated position, and then the loading was suddenly released. EMG recordings of 6 trunk muscles were acquired using a wireless surface EMG system. Onset and offset times were calculated from the EMG data. The intervention with ADIM was provided for 4 weeks. The onset and offset times were compared between pre- and post-intervention with ADIM. Results At the post-intervention, the onset of trunk flexors following release from trunk flexion loading became significantly earlier than pre-intervention (P = 0.028). The offset of flexors following release from trunk extension loading of post-intervention was significantly earlier than that of pre-intervention (P = 0.001). Conclusions We showed that the intervention with ADIM changed the EMG activity of trunk flexors in response to sudden release from loading. These results suggest a possibility that ADIM might be effective to improve the neuromuscular control of trunk flexors for the treatment of young patients with non-specific CLBP.

Objectives To investigate the prevalence and characteristics of chronic ankle instability (CAI) and copers among collegiate athletes as identified by criteria for research (CAI-R and copers-R) and for clinical practice (CAI-C and copers-C). Design Cross-sectional study. Setting University. Participants Collegiate athletes (n = 507). Main outcome measures Participants were assessed by questionnaires based on the International Ankle Consortium guidelines. The percentages of participants with CAI-R, CAI-C, copers-R and copers-C were calculated, respectively. Demographic and injury data were statistically compared between CAI-R and copers-R groups. Results The data of 470 participants was retained after exclusions. Of these, the prevalence of CAI-R (10.0%) was only half of that of CAI-C (19.8%), and that of copers-R and copers-C was about 5%. Seventy percent of unclassifiable participants had recurrent ankle sprains. CAI was most common in basketball, while copers were less prevalent in basketball, judo, rugby and gymnastics. The age at the initial injury was significantly younger in the CAI-R participants than in the copers-R. Conclusions The type of sport and the age at the initial injury may be associated with developing CAI. The standard criteria may not capture the entire clinical CAI population, therefore, care should be taken when applying the research to clinical practice.

Background A therapeutic target for patients with chronic musculoskeletal pain is the improvement of quality of life (QOL). A multidisciplinary approach to pain management is implemented at the Pain Management Center, Hoshi General Hospital, Japan. We consistently evaluate not only biological pain factors but also pain levels, psychosocial factors associated with pain, and QOL using questionnaires. The study aim was to explore the factors affecting QOL in patients with chronic musculoskeletal pain. Methods Subjects were 166 patients attending checkups at our pain management center from April 2015 to March 2020 who had valid questionnaire responses. We evaluated age, scores on the Brief Pain Inventory (BPI), Pain Catastrophizing Scale, Pain Disability Assessment Scale (PDAS), Hospital Anxiety and Depression Scale, Pain Self-Efficacy Questionnaire (PSEQ), EuroQol Five Dimensions Questionnaire, and Athens Insomnia Scale (AIS). Descriptive statistics were calculated for the 166 patients’ scores. Pearson’s product-moment coefficient correlations were calculated to examine associations among the variables. Subsequent multiple regression analysis, in which QOL was the dependent variable, resulted in a coefficient of determination (R2) of 0.58, indicating strong relationships among the variables (p p

Introduction Multidisciplinary pain management is a useful method for treating chronic musculoskeletal pain. Currently, few facilities in Japan offer multidisciplinary pain treatment, especially in the inpatient setting. We implemented a multidisciplinary pain management program based on International Association for the Study of Pain recommendations. This study described our initial efforts in implementing the program, and reported 3- and 6-month follow-up results. Materials and methods Our pain management team included orthopedic surgeons, psychiatrists, nurses, physical therapists, clinical psychologists, pharmacists, and nutritionists. The 3-week inpatient pain management program comprised exercise therapy, psychotherapy, and patient education. We evaluated patients using the Brief Pain Inventory (BPI), Pain Catastrophizing Scale (PCS), Pain Disability-Assessment Scale (PDAS), Hospital Anxiety and Depression Scale (HADS), Pain Self-Efficacy Questionnaire (PSEQ), EuroQol Five Dimensions (EQ-5D), and physical examinations (flexibility, muscle endurance, walking ability, and physical fitness). Statistical analyses were performed using paired t-tests and Wilcoxon matched-pairs signed-rank sum tests with Bonferroni correction after the Friedman test. Results Data for 23 patients were analyzed before and immediately after the program. Statistically significant improvements were seen in BPI, PCS, PDAS, HADS, PSEQ, EQ-5D, flexibility, muscle endurance, walking ability, and physical fitness. Eight patients were also assessed 3 and 6 months after the program. PCS (rumination and helplessness) scores and flexibility showed significant improvement at 3 and 6 months. Significant improvement was seen in PDAS and HADS (anxiety) scores and muscle endurance at 6 months, and in PSEQ scores immediately and at 3 and 6 months. Conclusion Our inpatient pain management program can improve patients' physical function and ability to cope with chronic musculoskeletal pain, which supports improved quality of life. Our program is currently being expanded to better assist patients with chronic musculoskeletal pain.

Objective To investigate the effects of knee flexion angle on peak torque, rate of torque development (RTD) during isometric contraction and hamstring flexibility after hamstring strain injury (HSI). Design Cross-sectional. Setting Controlled laboratory research. Participants Fourteen male athletes with a history of HSI and 14 athletes without HSI (controls). Main outcome measures: Hamstring flexibility was evaluated using active knee extension test. Isometric knee flexion peak torque and RTD were determined at 30°, 60°, and 90° of knee flexion measured by an isokinetic dynamometer. Results Individuals with a history of HSI had statistically significant, moderate deficits in isometric peak torque at 30° of knee flexion (P = 0.037; effect size = 0.55) in the HSI limb than in the uninjured limb, but not at 60° and 90° of knee flexion. In the control group, no significant differences in isometric peak torque at any angle were found between limbs. No differences in peak RTD and flexibility were found between limbs in both groups. Conclusions Isometric peak torque at 30° of knee flexion was lower in the injured limb than in the uninjured limb. Isometric strength deficits after HSI tended to be affected by lengthened hamstring angles.

Changes in working styles and physical activities, and an increase in psychological stress during the coronavirus disease 2019 (COVID-19) pandemic, may have affected pain conditions among workers with pain, however, these associations are still poorly understood. Therefore, we conducted a web-based, cross-sectional study to investigate these changes among Japanese workers suffering from pain. A total of 1941 workers who were aged 20–64 years and suffered from body pain within 4 weeks prior to the study were included. Information was collected using a self-reported questionnaire between July and August 2020. Among the respondents, 15% reported that their pain worsened during the COVID-19 pandemic. Approximately half of the workers claimed to have decreased physical activity (47%) and increased psychological stress (47%) during the pandemic. Multivariable logistic regression analyses found that telework (odds ratio 2.27, 95% confidence interval 1.68–3.06), decreased physical activity (3.18, 2.38–4.27), and increased psychological stress (2.16, 1.64–2.84) were associated significantly with pain augmentation. The group of workers who participated in telework and had decreased physical activity comprised the highest proportion of those with augmented pain. Our findings suggest that measures, which consider physical activities, psychological aspects, and working styles, to alleviate pain may be required for the working population in the future.

In order to investigate the presence (and amount) of the water (ice) molecules in the regolith 1 to 1.5 m below the lunar surface, a compact neutral particle mass spectrometer is under development. This neutral particle mass spectrometer is designed to install on a Moon rover, and it will perform mass analysis of neutral gas generated in the heating chamber. This mass spectrometer not only aims to measure the amount of water molecules included in the lunar regolith but also identify the atoms, molecules and their isotopes up to mass number 200 with mass resolution as high as 100.The mass spectrometer under development is a reflectron that is a Time-Of-Flight mass spectrometer. A standard reflectron consists of an ion source, ion acceleration part, free flight part, ion reflection part and an ion detector. Ionized neutral particles are accelerated in the two-stage ion acceleration part by a pulsed high voltage whose pulse timing is used as a start signal. The accelerated ions enter into the free flight part and reflected in the single-stage ion reflection part. Reflected ions again fly through the free flight part and detected by a detector. Ion mass is determined by the time difference between the start signal and the particle detection.In order to increase the mass resolution as much as possible within the allocated volume, we have decided to modify the standard reflectron by adding a second reflector that enables triple reflections and doubles the flight length. This newly designed triple-reflection TOF mass spectrometer can be operated also as a standard reflectron by changing the electric field configuration. Since the triple-reflection reduces the detection efficiency while increasing the mass resolution, the single reflection mode is used as a complementary mode where the detection efficiency is higher while the mass resolution is lower.

Background: Lateral trunk obliquity during landing is one of the characteristics of anterior cruciate ligament (ACL) injuries in female athletes. Knee biomechanics during landing with lateral trunk obliquity may be different between female and male subjects. The purpose of the present study was to compare kinetics and kinematics in female subjects during landing with lateral trunk obliquity with those in male subjects.Methods: Fifteen female (age 22.0 ± 1.6 years) and 15 male subjects (age 21.7 ± 1.1 years) participated in this study. The subjects performed a single-leg landing from a 30-cm-high box. Subjects were instructed to keep inclining their trunk to landing leg side at 15° from vertical line. Kinetics and kinematics of their hip and knee joints were analyzed using a three-dimensional motion analysis system with a force plate and compared between female and male subjects.Results: There were no significant differences in the angle of the laterally inclined trunk at initial contact (IC) and at the time of peak vertical ground reaction force (VGRF) (P = 0.341, 0.363). The peak VGRF was smaller in female subjects than male subjects (P = 0.047). Hip adduction moment at the time of peak VGRF was significantly larger in female subjects than male subjects (P = 0.042). Hip external rotation of female subjects at IC was significantly larger than that of male subjects (P = 0.012). There were no differences in knee moments or kinematics between female and male subjects.Conclusions: The findings of the present study indicated that female athletes are considered to avoid excessive knee abduction moment during landing with lateral trunk obliquity by kinematic and kinetic changes in their hip joint. Therefore, sports-medicine specialists should take more notice of kinematics and kinetic behaviors around hip joint in order to prevent noncontact ACL injuries for female athletes.

GEO-X (GEOspace X-ray imager) is a 50 kg-class small satellite to image the global Earth’s magnetosphere in X-rays via solar wind charge exchange emission. A 12U CubeSat will be injected into an elliptical orbit with an apogee distance of ∼40 Earth radii. In order to observe the diffuse soft X-ray emission in 0.3-2 keV and to verify X-ray imaging of the dayside structures of the magnetosphere such as cusps, magnetosheaths and magnetopauses which are identified statistically by in-situ satellite observations, an original light-weight X-ray imaging spectrometer (∼10 kg, ∼10 W, ∼10×10×30 cm) will be carried. The payload is composed of a ultra light-weight MEMS Wolter type-I telescope (∼4×4 deg2 FOV

The present study aimed to clarify the mechanisms of postural control during standing in older adults and document the mechanisms of age-related motor control based on changes in muscle activities.A total of 26 healthy male adults (older adult group, ≥65-78 years: n = 16; younger adult group, 20-23 years: n = 10) participated in this study. Ground reaction force and kinematic data of the lower limbs (hip, knee, and ankle), and electromyographic data from 6 postural muscles on the right side were recorded and quantified for each motor phase during rapid voluntary center of pressure (COP) shift.Although hip strategy was more frequently observed in older adults than in young adults (56.3% vs. 20.0%), no muscle activity of hip agonists was observed in some (31.3%) older adults. Furthermore, older adults had a statistically significant delay in the inhibition of postural muscles during anticipatory postural adjustments (p 0.05). After the onset of COP motion, the co-contraction time between agonists and antagonists was significantly prolonged in the older adults than in the younger adults (p 0.05), and the reciprocal muscle pattern was unclear in the older adults. Prior to the termination of movement, agonist activity continued longer in the older adult group than in the younger adult group; that is, inhibition was insufficient in the older adult group.A series of postural strategies during the voluntary movement task were altered in older adults, and this was significantly related not only with the activation but also the inhibition of postural muscles.

Accepted: 2018-04-25, 資料番号: SA1180021000

Naoto Takahashi,1,2 Satoshi Kasahara,1,2 Shoji Yabuki1,2 1Department of Pain Medicine, Fukushima Medical University School of Medicine, Fukushima, 2Pain Management Center, Hoshi General Hospital, Koriyama, Japan Introduction: Multidisciplinary pain management is a useful method to treat chronic musculoskeletal pain. Few facilities in Japan administer a multidisciplinary pain management program, especially an inpatient program. Therefore, we implemented a multidisciplinary pain management program in our hospital based on biopsychosocial factors guided by the recommendations of the International Association for the Study of Pain. The purpose of this study is to describe our inpatient pain management program for Japanese patients, which uses the biopsychosocial method of pain self-management. Materials and methods: Fourteen patients with intractable chronic musculoskeletal pain, who were implemented a multidisciplinary pain management program in our hospital, were studied using the evaluation of the pain and associated factors and physical function. Results: Significant improvement in outcomes were seen in the brief pain inventory, the pain catastrophizing scale (rumination, magnification, and helplessness), the pain disability assessment scale, the hospital anxiety and depression scale (anxiety and depression), the pain self-efficacy questionnaire, the EuroQol five dimensions questionnaire, and muscle endurance and physical fitness. We found no statistically significant differences in static flexibility or walking ability. Conclusion: We developed an inpatient chronic pain management program for Japanese patients. Our results suggest that our program improves chronic musculoskeletal pain coping mechanisms, and that the program can improve patients’ quality of life and some physical function. This inpatient pain management program is being expanded to better help intractable chronic musculoskeletal pain patients. Keywords: chronic musculoskeletal pain, multidisciplinary pain management, biopsychosocial model, inpatient pain management program

Objective The generic STarT Back 5-item screening tool (STarT-G) is used to manage chronic pain in the lower back and elsewhere. This study evaluated the validity of the Japanese version of this generic screening tool. Materials and methods Japanese participants between the ages of 20 and 64 years completed online surveys regarding pain. Survey reliability was assessed with internal consistency, as calculated using Cronbach's alpha coefficients. Spearman's correlation coefficients were used to evaluate concurrent validity between the STarT-G score and standard reference questionnaires. Associations between STarT-G scores and the presence of a disability due to chronic pain (DCP) were analyzed using receiver operator characteristic (ROC) curves. Results Analyses ultimately included data obtained from 52,842 Japanese participants (54.4% male) with a mean (standard deviation) age of 47.7 (9.4) years. Approximately 1.5% of participants had DCP, and the mean STarT-G score was 1.2 (1.4). The Cronbach's alpha coefficient was 0.71, indicating an acceptable reliability. The STarT-G score moderately correlated with the pain numerical rating scale (NRS) score (Spearman's correlation coefficient: r = 0.34). When the STarT-G threshold was set at 4, the sensitivity and specificity of the DCP predictive model were 65.8% and 82.4%, respectively, and the area under the ROC was 0.808. Conclusion The STarT-G was internally consistent and was able to distinguish between subjects with and without a DCP. Therefore, the STarT-G can reliably be used in the Japanese population to identify patients with DCP.

Aims: To investigate rates of attention-deficit hyperactivity disorder (ADHD) in patients with chronic pain attending a pain clinic, the effects of a screening measure for ADHD in patients with chronic pain, and the effects of ADHD drugs on both pain and ADHD symptoms. Methods: We retrospectively surveyed 110 patients with chronic pain visiting the Anesthesiology and Pain Relief Center at the University of Tokyo in Japan, who had also consulted a psychiatrist, between April 2012 and July 2015. Results: Of the total of 110 patients with chronic pain, 35 (31.8%) were also diagnosed with ADHD, and the average Wender Utah Rating Scale (WURS) score among the ADHD patients was 39.0 ± 22.1 (n = 25). Only 36.0% of these patients exceeded the cutoff value, suggesting that 64.0% of the patients with ADHD were not identified by screening with the WURS. Twenty-six patients initiated treatment with ADHD medication, with dosage adjustment completed in 21. Of these 21 patients 20 (95.0%) had improved ADHD symptoms. Improved pain symptoms were observed in 14 patients (66.6%), with a reduction in the pain numerical rating scale of 64.7% ± 30.1%. Conclusions: This is the first study investigating the comorbidity of ADHD and chronic pain at pain clinics showing a high level of comorbidity and amelioration of pain and ADHD symptoms with treatment. Careful interpretation is required when the WURS is used to screen patients with chronic pain.

For older adults, falls often occur when transitioning from motion to a complete stop, as the motor control required during this phase is very complex and challenging. The purpose of this study was to clarify the effect of aging on the motor control required to terminate motion. Twenty-five healthy older adults (aged65 years) and 25 healthy young adults (20-23 years) performed a rapid stopping task while standing on a force plate. The rapid stopping task was conducted by analyzing center of pressure (COP) on the force plate during a visually guided tracking experiment. To assess the ability to terminate motion, we measured the velocity waveform for the COP, along with the reaction, propulsion, braking, and total movement times. Both the reaction and movement times of the older-adult group were significantly longer than those of the younger-adult group (all, p 0.05). There was no significant difference between the groups in regard to the initial backward propulsion time; however, in the subsequent sequence of backward braking, forward propulsion, and backward braking, all times were longer in the older-adult group than in the younger-adult group (p 0.05). Our results show that the series of time delays shown by older adults when initiating and terminating motion is due to not only delayed reactions but also delayed stopping. Furthermore, our findings suggest that older adults have not only a diminished propulsion ability but also a diminished braking ability.

Clinical anesthesiologists, particularly residents, work in stressful environments. However, evidence-based physiological and psychological tests to evaluate stress are still lacking. In this single-center study of 33 residents, we investigated the relationship between heart rate variability (HRV), which had the potential to screen residents’ stress levels using Holter electrocardiography (ECG) and psychological mood as assessed by the Profile of Mood States (POMS) questionnaire. HRV analysis revealed 2 findings. Firstly, standard deviation of the average of 5-min normal-to-normal R–R intervals (SDANN) was significant lower than that of same-aged healthy volunteers (69.3 ± 27.9 vs. 137.0 ± 43.0 ms, P

著者人数: 14名, Accepted: 2018-05-01, 資料番号: SA1180022000

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

Preventing fall-related injuries is becoming a priority as the world population ages. This study's purpose was to examine the effect of aging on vertical postural control in the community-dwelling elderly. Thirty-six elderly individuals and twenty-two healthy young adults were asked to shift their centers of pressure (COPs) as far as possible while standing. The COP position, angle of each lower leg joint, and postural muscle activities were measured using a force plate, three-dimensional motion analyzer, and electromyogram, respectively. The vertical position of the center of mass (COM) was also measured to assess the change in vertical postural control. The backward COP shift in the elderly group was significantly smaller than that in the young group, and both the forward and backward COM shifts were significantly smaller in elders relative to those in youths. The COM position in the elderly group during the backward COP shift was also significantly lower than that in the young group. Knee and ankle joint movements differed between the two groups during the backward COP shift. Factor analysis indicated that dorsal and ventral muscle groups were involved in the COP shift. Specifically, the relationship between the biceps femoris muscle and the voluntary COP shift was reinforced in the elderly group. These findings suggest that the vertical postural strategy changes in the elderly during the backward COP shift.

[Purpose] The aim of this study was to quantitatively investigate gender differences in trunk muscle strength and activity and to verify the two proposed field tests for screening the muscle strength of trunk flexors by use of surface EMG (sEMG). [Subjects and Methods] Fifty-four healthy young volunteers participated in this study and RA strength was evaluated using the curl-up (CU) and double-leg-lower (DLL) tests. All muscle activity that occurred in the upper and lower RA sites during the two tests was recorded using sEMG. The sEMG data were then normalized using the maximum voluntary contraction. To investigate the validity of the two tests, the ratio of muscle activity between the upper and lower RA sites was calculated. [Results] The reliability of the CU and the DLL tests were estimated using the intraclass correlation coefficient and the values ranged from 0.84?0.96 and 0.93?0.98, respectively. Muscle activity was significantly higher in females than in males in all tests except one of the DLL tests. The activity ratio with respect to each muscle grade was constant between the CU and the DLL tests. [Conclusion] Our results indicate that trunk muscle activity is affected by gender, and the tests should be selected according to purpose.

Accepted: 2010-03-23, 資料番号: SA1002696000

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

[Purpose] To quantitatively investigate whether the muscle grades of the Curl-up (CU) and Double-leg-lowering (DLL) test show any electromyographic changes in the upper and lower rectus abdominis (RA) as trunk flexors. [Methods] The muscle activities of both the upper and lower RA in thirty healthy young males were recorded during each muscle grade task of two tests. The percentages of maximum voluntary contractions (%MVC) of the upper and lower RA were compared between each muscle grade and test. The %MVC ratios of the upper and lower RA were calculated to investigate the contribution of each muscle site in two tests. [Results] Although there were significant electromyographic differences among muscle grades in the CU test, there was no significant difference in the DLL test. The %MVC from both sites in the CU test were significantly larger in all muscle grades than in the DLL test. However, the %MVC ratio was consistently ~1.0 in both tests and the contribution of each muscle site did not differ. [Conclusion] These findings suggest that the three grading tasks used in this manual muscle testing procedure may be insufficient to objectively detect muscle weakness in the trunk flexors. The grading criterion for trunk flexors may need remediation.

From the viewpoint of plasma particle measurements in the radiation belt, background noise is a serious problem. High-energy particles penetrating the sensor shielding generate spurious signals, and their count rate often can be comparable to the true signals. In order to attenuate such background noise during medium-energy (5–83 keV) electron measurements, we propose the double energy analyses (DEA) method. DEA is conducted by a combination of an electrostatic analyser (ESA) and avalanche photo-diodes (APDs); ESA and APD independently determine the energy of each incoming particle. By using the DEA method, therefore, the penetrating particles can be rejected when the two energy determinations are inconsistent; spurious noise are caused only when the deposited energy at an APD is by chance consistent with the measured energy by ESA. We formulate the noise count rate and show the advantage of DEA method quantitatively.

With two electron beam sources, we have tested two new Hamamatsu [Hamamatsu Photonics K.K., Shizuoka, Japan 〈 http://www.hamamatsu.com/ 〉 ] avalanche photodiodes (APDs) of spl 3988 and spl 6098 to detect electron beams up to 100 keV. Though our previous results showed the effectiveness and the advantage of an APD to measure 2–40 keV electrons, its upper limit was not high enough to detect so-called medium-energy electrons. In addition to the limitation of its detectable range, the response at different energies was also not linear. These newly developed APDs, which have thicker depletion-layers, provide full coverage of this missing range along with a good linearity. The depletion-layer thickness was increased to 140 μ m for both APDs, the dead-layer of spl 3988 became 10 times thicker than that of spl 6098. The thin-surface dead-layer and thick depletion-layer of spl 6098 allows the detection of electrons from 3 keV up to 100 keV with a good linearity and with an excellent energy resolution of 4 keV at 100-keV electrons. The wide dynamic range from 3 keV to 100 keV of those APDs will increase their appeal in detecting electrons for space plasma research.

〔目的〕胸部あるいは腰部コルセットの圧迫による呼吸機能への影響を調べた。〔対象〕健常成人男性6名（28.2±5.3 [SE]歳）。〔方法〕締め付け圧を調整出来る胸部コルセットと腰部コルセットを別々に装着し，締め付け圧0 mmHg, 20 mmHg，40 mmHg, 60 mmHgの条件で肺気量分画を測定した。〔結果〕胸部コルセット装着は，締め付け圧が増加すると肺活量，予備呼気量，全肺気量は減少した。1回換気量も減少したが有意差はなく，呼吸数の増加で分時換気量が維持されていた。全肺気量，肺活量，予備呼気量，努力性肺活量の減少は胸部コルセット締め付け圧＝40 mmHgからみられた。なお，残気量は締め付け圧に関係なく影響しなかった。一方，腰部コルセット装着は締め付け圧に関係なく予備呼気量を除く他の肺気量分画に影響しなかった。〔結語〕胸部コルセットを使用する場合は，コルセットが呼吸運動を抑制する危険性を考慮すべきである。

It is still unclear how rehabilitative intervention assists recovery from strokes. In order to address this question, we made an animal model to examine the recovery process after experimental strokes. The forelimb movements in 2 monkeys retrieving food from a well were analyzed with a videotape recording. A small infarction by coagulation of blood vessels was made in the forelimb areas after mapping of the primary motor areas. The recovery process was evaluated by measuring the time required for taking food. We used the modified Kluver board with the small diameter in order to restrict the monkeys' compensatory movements such as pronation or supination. After the infarction, the monkeys could not use their impaired hands for the first 2 days. Failure to retrieve food and compensatory movements such as involvement of other joints were often observed during the first week. However, the forelimb function of both monkeys showed no significant impairments on the 6th week, compared to the results before the infarction. Throughout the experiments, the monkeys showed no supination or pronation of the forearm. These results suggest that this animal model with the modified Kluver board may be useful for the evaluation of motor deficit.

The smooth-pursuit system moves the eyes in space accurately to track slowly moving objects of interest despite visual inputs from the moving background and/or vestibular inputs during head movements. Recently, our laboratory has shown that young primates exhibit asymmetric eye movements during vertical pursuit across a textured background; upward eye velocity gain is reduced. To further understand the nature of this asymmetry, we performed three series of experiments in young monkeys. In Experiment 1, we examined whether this asymmetry was due to an un-compensated downward optokinetic reflex induced by the textured background as it moves across the retina in the opposite direction of the pursuit eye movements. For this, we examined the monkeys’ ability to fixate a stationary spot in space during movement of the textured background and compared it with vertical pursuit across the stationary textured background. We also examined gains of optokinetic eye movements induced by downward motion of the textured background during upward pursuit. In both task conditions, gains of downward eye velocity induced by the textured background were too small to explain reduced upward eye velocity gains. In Experiment 2, we examined whether the frame of reference for low-velocity, upward pursuit was orbital or earth vertical. To test this, we first applied static tilt in the roll plane until the animals were nearly positioned on their side in order to dissociate vertical or horizontal eye movements in the orbit from those in space. Deficits were observed for upward pursuit in the orbit but not in space. In Experiment 3, we tested whether asymmetry was observed during head-free pursuit that requires coordination between eye and head movements. Asymmetry in vertical eye velocity gains was still observed during head-free pursuit although it was not observed in vertical head velocity. These results, taken together, suggest that the asymmetric eye movements during vertical pursuit are specific for upward, primarily eye pursuit in the orbit.

The ERG (Exploration of energization and Radiation in Geospace) is Japanese geospace exploration project. The project focuses on relativistic electron acceleration mechanism of the outer belt and dynamics of space storms in the context of the cross-energy coupling via wave-particle interactions. The project consists of the satellite observation team, the ground-based network observation team, and integrated-data analysis/simulation team. The satellite was launched on December 20 2016 and has been nicknamed, "Arase". This paper describes overview of the project and future plan for observations.

To the Editor: The role played by the brain's dopamine system in pain control has garnered attention in recent years.1 Herein, we report 4 cases of long-term chronic pain (pain disorder [DSM-IV-TR]) that improved dramatically following administration of a low dose of aripiprazole, a partial dopamine agonist. None of these 4 patients satisfied the DSM-IV-TR diagnostic criteria for schizophrenia. Case 1. Mr A, a 42-year-old man, had a chief complaint of chronic head and neck pain that had persisted for 10 years and was refractory to administration of morphine 70 mg/d. He visited our department in December 2008 and was diagnosed with pain disorder and pervasive developmental disorder. Although fluvoxamine treatment was started, with the dosage gradually increased to 200 mg/d, it was ineffective and the pain exacerbated. Upon switching to aripiprazole 3 mg/d, the pain improved dramatically, and the patient was able to discontinue morphine. After increasing the dose to 6 mg/d, the patient became able to go fishing for the first time in a few years, and his motivation increased. Case 2. Mr B, a 35-year-old man, had chronic back and leg pain that had persisted for 15 years and particularly worsened following sexual intercourse. He had visited over 20 medical institutions in the past and had not responded to antidepressants. He visited our department in March 2009 and was diagnosed with pain disorder. Pain disappeared after initiation of aripiprazole 2 mg/d, and the patient's passion for his work in computer software development improved. As aripiprazole was effective in the treatment of pain disorder in Cases 1 and 2, we subsequently also used it for Cases 3 and 4, and it was effective. Below are concise descriptions of Cases 3 and 4. Case 3. Ms C, an 83-year-old woman, had developed Parkinson's disease and back and leg pain (pain disorder) 4 years before. She visited our department in August 2009. Pain improved following administration of aripiprazole 3 mg/d, and the patient began going out rather than staying home as she had been, and her level of activity improved. Case 4. Ms D, a 68-year-old woman, had developed pain at the top of the head (pain disorder) a year before she visited our department in October 2009. Pain disappeared after we added aripiprazole 2 mg/d to sertraline 100 mg/d, and the patient's motivation toward housework improved. These 4 patients were characterized by reduction of pain and improved motivation following low-dose aripiprazole administration. Dopamine plays a role in pain processing via μ opioids.1 Dopamine-related diseases often exhibit pain-related symptoms. For example, pain is a common complaint among patients with Parkinson's disease,2 and those with schizophrenia are known to have a reduced pain sensitivity.3 In other words, the degree of dopamine system activation is inversely proportional to the degree of pain. These 4 cases suggest that aripiprazole, a dopamine system stabilizer, may be a therapeutic option for chronic pain.

This study assessed the relationship of each movement direction on the lumbar spine and on the pelvis in regards to lumbar-pelvic coordination in the sitting position. Lumbar and pelvic motions were recorded using a flexible electrogoniometer in 12 healthy subjects during two different tasks in the sitting position. The coordination of the lumbar spine and pelvis was evaluated using the ratio of lumbar and pelvic angles (L/P ratio hereafter) in three motion phases. There were significant differences in the L/P ratio values between during the "forward bending" and "rising from a forward flexed position" phases (P0.01). The L/P ratio value ( approximately -0.7) was consistent during the movement from an erect to a slumped sitting position as the lumbar spine and pelvis moved in opposing directions. This study shows that lumbar-pelvic coordination occurs in the sitting position. Lumbar-pelvic coordination is confirmed even if the movement tasks are different in the sitting position, and these findings show that aspects of a particular movement are dependent on the given movement task. These findings may provide greater insight into the kinematic changes involved in lumber-pelvic coordination, and help clinicians implement sitting exercises conducive to the independence of the patient.

Background: A reaching movement is an important action in daily life. When a reaching movement is directed to a target placed at a distance greater than arm length in standing, a driving or braking force must be created to initiate and to terminate whole body movement (Tyler and Karst, 2004). Therefore, the central nervous system activates postural muscles at an appropriate timing and subsequent initiates joint motion in lower limb. Though it is well known that motor components such as the peak velocity of arm movements improve through reaching training, it remains unclear how postural components improve. Purpose: The repeated reaching training is widely adopted as one of rehabilitation programs on a clinical treatment. However, changes in postural control during reaching training have been rarely reported. Therefore, the purpose of this study is to investigate change in muscle activity and joint angle of lower limbs through repeated reaching training in standing posture. Methods: Fifteen healthy subjects (23± 2 years) participated. All subjects provided written informed consent, as approved by the ethics committee of Hokkaido University Faculty of Health Sciences. Subjects performed reaching to a small target placed in the nearly maximum reach distance as quickly as possible. One hundred trials of reaching with right arm were repeated for three consecutive days and they were examined again after discontinuing training for one day. The surface electromyography (EMG) of tibialis anterior (TA) and gastrocnemius (GAS) was recorded. Kinematic data were collected using a three-dimensional motion analysis system. The integrated EMG (IEMG) were calculated for driving phase (from the reaching onset to the time when hand velocity was maximal) and braking phase (from the time when hand velocity was maximal to termination time of reaching). Hip, knee, and ankle joint angles were calculated. Mean value of the parameters in the first 10 trials on the first training day were compared with those of the other 10 trials on the first training day, and with those of the first 10 trials on the other training day using one-way repeated measure ANOVA and a post-hoc test. The significance level was set at p< 0.05. Results: On the first day, the normalized IEMG of the right TA in driving phase (p< 0.01) and the left GAS in braking phase (p< 0.01) significantly increased through repeated reaching training. Also, the maximum ankle dorsiflexion angle in driving phase (p< 0.05) and the maximum hip flexion angle in braking phase (p< 0.05) significantly increased. Training effects on these parameters were retained after a two-day rest period. Conclusion(s):We found that changes in postural control occurred in both driving and braking phase during a repetitive reaching task. Training effects were retained after subjects discontinued training. These results suggest postural learning not only to initiate thewhole body forwardmovement but also to terminate the movement occur during a repetitive reaching task. Implications:A better understanding of the postural control mechanism during repetitive reaching training is useful for physical therapy practices.