[Purpose] To assess the agreement between our custom Bluetooth IS system and the gold standard MOCAP system during gait. Bluetooth inertial movement sensors (IS) allow for real-time movement analysis with fewer restrictions than optoelectrical motion capture systems (MOCAP) and more accessibility than wireless IS systems. [Participants and Methods] We collected simultaneous Bluetooth IS and MOCAP data for 16 young participants walking at a self-selected speed. Sensors were placed on the right thigh and shank. Segment angles and stride length were calculated and compared between systems using Pearson’s correlation coefficients (R), intra-class correlation coefficients (ICC), root mean square errors (RMSE), limits of agreement (LOA), and Bland-Altman plots. [Results] R values ranged from 0.371–0.715; ICC values ranged from 0.263–0.770. RMSE was 0.369 m for stride length and ranged from 6.85–13.07° in segment angles. Limits of agreement were −0.01–0.66 m for stride length and ranged from −27.71–20.53° in segment angles. [Conclusion] The Bluetooth IS system showed moderate agreement with MOCAP. Bluetooth IS could be used for reliable gait analysis with fewer space requirements and more portability than wireless IS or MOCAP systems. Bluetooth IS could be used outside of the clinic for real-time monitoring of gait during daily life.

[Purpose] Few studies have assessed the reliability of muscle strength measurement using a hand-held dynamometer, specifically in Japanese young children. This study aims to investigate the reliability, minimal detectable change and measurement error in knee extension muscle strength measurements in young children using a hand-held dynamometer. [Participants and Methods] The study participants comprised 36 kindergarten-enrolled children of 3–6 years age. An experienced physiotherapist measured their isometric knee extension strength. Appropriate orientation and practices were performed prior to measurement. The same physiotherapist took the muscle measurements twice; and the maximum value was used as the muscle strength value. The measurements were repeated at intervals of approximately 30 min to verify reproducibility. [Results] The initial isometric knee extension strength was 10.6 ± 3.3 kgf and the Intra-class correlation coefficient (1,1) was 0.765. The standard error of measurement was 1.6 kgf and the minimal detectable change was 4.4 kgf. No significant systematic errors were observed. [Conclusion] Isometric knee extension strength measurement using a hand-held dynamometer in young children has good reliability with a low risk of systematic errors.

[Purpose] The quality of physical functions was evaluated prospectively in older females over a 5 year period to identify the physical functions that are more likely to consistently decline or be maintained in females aged 65‒74 years and more than 75 years. [Participants and Methods] Physical functions, including grip strength, walking speed, and balance, were measured for older females aged 65–74 years group and more than 75 years group from 2015 to 2019. T-scores of the physical performances were calculated to analyze the changes in the physical functions over 5 years. [Results] Based on the T-scores, physical functions in terms of the 5-m walking speed, timed up-and-go test, and functional reach test, improved from 2015 to 2019 in the 65–74 group, whereas all physical functions consistently deteriorated in the older than 75 group. [Conclusion] There was no significant decline of the physical functions in both groups; however, the T-score variations for physical functions during the 5 year observation period differed in each group.

[Purpose] We aimed to examine the effects of pain-related catastrophic thoughts and anxiety/depression on pain intensity and quality of life (QOL), and how these effects (relationships) vary with pain location, in outpatients with chronic pain. [Participants and Methods] We recruited 14 participants with low back pain (2 males and 12 females) and 14 with knee joint pain (3 males and 11 females). We used the following evaluation tools: the visual analog scale (to evaluate pain intensity), pain catastrophizing scale (in which scores are categorized into helplessness, rumination, and magnification), Hospital Anxiety and Depression Scale (for psychodynamic evaluation), and a questionnaire for QOL evaluation. [Results] There was no difference in pain intensity between the groups. The “low back pain” group showed a positive correlation between pain intensity and anxiety, while the “knee pain” group showed a positive correlation between pain intensity and helplessness. The “low back pain” group showed a negative correlation between health in QOL assessment items and helplessness, and between health and magnification. However, in the “knee pain” group, there was a negative correlation between health and rumination, between health and anxiety, and between positive mental attitude and magnification. [Conclusion] Mental status varied depending on the pain location, regardless of the intensity of the pain. This suggests that a psychological approach dependent on pain location is needed during physical therapy.

[Purpose] This study aimed to verify the utility of an image analysis freeware in the evaluation of thoracolumbar spine and hip joint movements during sit-to-stand movement and show the importance of separately analyzing the movements of the thoracolumbar spine and the hip joint. [Participants and Methods] We used a two-dimensional image analysis freeware to analyze the kinematics of the thoracolumbar spine and the hip joint during sit-to-stand movements in seven healthy young males. We further examined the usefulness of the freeware by verifying the concordance of its angle measurements with those of a three-dimensional motion analysis device. Moreover, we evaluated joint coordination of the thoracolumbar spine with hip joint movements in pregnant female before and after delivery by measuring the relative phase angle. [Results] The trunk angle and relative phase angle between the thoracolumbar spine and the hip joint obtained using the two different analytical methods were fairly consistent. In the analysis of the pregnant female, the degree of thoracolumbar flexion prior to hip flexion tended to decrease. Similarly, the degree of hip extension tended to decrease during pregnancy. [Conclusion] This study shows that a two-dimensional image analysis freeware could be useful and meaningful in the calculation of thoracolumbar spine and hip joint movements and in the detection of synergistic patterns of these entities during sit-to-stand movement.

[Purpose] Rotating hinge knee prostheses are often used in primary total knee arthroplasty. However, the biomechanics resulting from this treatment remain unexplored. This cross-sectional study compared patient data on gait kinetics and kinematics to assess the efficacy of primary total knee arthroplasty using a rotating hinge knee or other prostheses. [Participants and Methods] Thirty-three participants were assigned to the following groups: rotating hinge knee (n=7); cruciate-retaining prosthesis (n=7); untreated osteoarthritis (n=10); and young adults as a reference group (n=9). Participant data on biomechanical and spatiotemporal parameters were analyzed. [Results] The postoperative course of the rotating hinge knee group was not significantly longer than that of the cruciate-retaining prosthesis group. The knee varus angle and adduction moment of the rotating hinge knee group were significantly smaller than those of the untreated osteoarthritis group. Gait kinetics and kinematics were not different between the rotating hinge knee and cruciate-retaining prosthesis groups. [Conclusion] Participants who had undergone primary total knee arthroplasty with a rotating hinge knee prosthesis had worse preoperative conditions and demonstrated a similar postoperative gait as those who had undergone total knee arthroplasty with other prostheses. Our findings may be used to tailor rehabilitation programs for participants who have undergone total knee arthroplasty with a rotating hinge knee implant.

[Purpose] We aimed to clarify the characteristics of age-related changes based on the body composition data of old and super-old nursing home residents. [Participants and Methods] This cross-sectional study included 53 female nursing home residents aged 75 years and above (mean age: 89.4 years; standard deviation: 5.6 years). They were divided into the old and super-old groups. The old group consisted of 24 participants aged between 75 and 89 years (mean age: 84.4 years; standard deviation: 3.7 years). The super-old group consisted of 29 participants aged 90 years and above (mean age: 93.5 years; standard deviation: 2.7 years). The parameters such as phase angle, skeletal muscle mass index, skeletal muscle mass, body fat percentage, body mass index, and Barthel index were examined in the two groups. The relationship between age and phase angle was determined, and the partial correlation coefficient was analyzed using the items for which a significant difference was found between the two groups as adjustment variables. [Results] The overall phase angle was 3.2 degrees, and that of the super-old group alone was 2.6 degrees. Age-related difference was observed in the phase angle and Barthel index. A significant correlation of −0.53 was observed between age and phase angle. The Barthel index-adjusted partial correlation coefficient between age and phase angle was −0.35. [Conclusion] The results of this study indicated that phase angle is an indicator of physical condition associated with aging in female nursing home residents aged 75 to 100 years.

[Purpose] To demonstrate the reduction of lumbar hyperlordosis, sacral base angle and anterior thoracic translation posture in an 11-year-old female. [Participant and Methods] A pediatric patient presented with lumbar hyperlordosis and underwent Chiropractic BioPhysics^® treatment protocols to reduce her spinal deformity and correlated symptoms. Symptoms included thoracolumbar, hip, knee and ankle pains and lower extremity weakness. Radiographs confirmed lumbar hyperlordosis, increased sacral base angle and a forward translated thoracic posture. Spinal traction as well as corrective exercises and spinal manipulative therapy was performed over an 11-month period. [Results] After 57 treatments, there was a 13.4° reduction in L1-L5 lordosis, an 11.8° reduction in sacral base angle and a 13.8 mm reduction in anterior thoracic translation. The improved structural changes correlated with improved symptoms. [Conclusion] Lumbar hyperlordosis can be reduced in pediatric patients presenting with hyperlordosis and associated symptomatology. Routine radiography may be warranted in the diagnosis of lumbar spine deformities in pediatrics. Further research into the non-surgical reduction of lumbar spine hyperlordosis is needed.

The authors would like to apologize for the mistakes in PARTICIPANTS AND METHODS.

In line 3 of PARTICIPANTS AND METHODS (p 427) “approval number: 14014” should have been “approval number: 17006”.

In line 5 of PARTICIPANTS AND METHODS (p 427) 32 elderly patients (8 males, 26 females) should have been 32 elderly patients (8 males, 24 females).