A pilot study on the functional outcome using markerless motion analysis tool and surface emg of nerve transfers for upper trunk brachial plexus injuries

INTRODUCTION@#Brachial plexus injuries (BPI) have devastating functional effects. Clinical outcomes of BPI reconstruction have been documented in literature; however, these do not use EMG and quantitative kinematic studies.@*OBJECTIVE@#This study aims to use a markerless motion analysis tool (KINECT) and surface EMG to assess the functional outcomes of adult patients with traumatic upper trunk BPI who have undergone nerve transfers for the shoulder and elbow in comparison to the normal contralateral limb.@*METHODS@#This is an exploratory study which evaluated three participants with BPI after nerve reconstruction. KINECT was used to evaluate the kinematics (range of motion, velocity, and acceleration) and the surface EMG for muscle electrical signals (root mean square, peak EMG signal, and peak activation time) of the extremities. The means of each parameter were computed and compared using t-test or Mann-Whitney U test.@*RESULTS@#Participant C, with the best clinical recovery, showed mostly higher KINECT and EMG values for the BPI extremity. There was a significant difference between the KINECT data of Participants A and B, with lower mean values for the BPI extremity. Most of the EMG results showed lower signals for the BPI extremity, with statistical significance.@*CONCLUSION@#The KINECT and surface EMG provide simple, cost-effective, quick, and objective assessment tools. These can be used for monitoring and as basis for formulating individualized interventions. A specific algorithm should be developed for the KINECT sensors to address errors in data collection. A fine needle EMG may be more useful in evaluating the muscles involved in shoulder external rotation.

Examination of Kinematic Factors during Single Leg Squatting Associated with the Occurrence of Re-injury after Anterior Cruciate Ligament Reconstruction / The Japanese Journal of Rehabilitation Medicine

Objective：This study aimed to determine the difference in knee joint range of motion (ROM) and coefficient of variation (CV) during preoperative single-leg squatting in patients who developed ipsilateral lower limb anterior cruciate ligament (ACL) re-injury months after ACL reconstruction and in those who did not have the injury.Methods：Participants included 38 patients with non-contact ACL injuries. All patients underwent single-leg squatting the day before ACL reconstruction. Knee joint ROM and CV were assessed during single-leg squatting using a three-dimensional motion analysis system. We investigated the occurrence of ACL reinjury in the ipsilateral lower limb approximately 30 months after ACL reconstruction. Knee joint ROM and CV were then compared between the postoperative and non-injury groups.Results：The postoperative injury and non-injury groups included 9 and 29 patients, respectively. The knee internal/external rotation ROM and CV of knee varus/valgus ROM were greater in the postoperative injury group than in the postoperative non-injury group.Conclusion：During single-leg squatting before ACL reconstruction surgery, the knee internal/external rotation ROM and CV of knee varus/valgus ROM were suggested to be points of evaluation when considering ACL re-injury prevention.

Differences in the Kinematic and Kinetic Characteristics between Successful and Failed Sit-to-stand Trials in Patients with Stroke / The Japanese Journal of Rehabilitation Medicine

Objects：Sit-to-stand (STS) interventions are frequently used as part of stroke rehabilitation. This study aimed to clarify the kinematic and kinetic characteristics of patients recovering from stroke, who have difficulties with STS movement.Method：The participants included 26 stroke patients who struggled to complete the STS maneuver. Using a 3D motion analysis system, the kinematic and kinetic parameters during STS were retrospectively analyzed and compared between failed and successful trials. The kinematic parameters of the trunk and lower limbs were obtained within the seat-off phases, and the kinetic indices of the lower limbs were obtained from measurements taken before and after the seat-off phase. The weight-bearing ratio on the unaffected side was calculated from the vertical ground reaction forces.Results：In the successful trials, analyses of the parameters revealed more forward tilting of the pelvic and thoracic regions, a further forward and downward shift of the center of mass, and larger hip and knee extension moments than those of the failed trials. However, there was no difference in the weight-bearing ratio on the non-paralyzed side.Conclusion：This study revealed that the kinematic and kinetic properties of the STS maneuver differed between successful and failed trials among patients with stroke. The study therefore provides useful information for clinical evaluation and rehabilitation.

Differences in the Kinematic and Kinetic Characteristics between Successful and Failed Sit-to-stand Trials in Patients with Stroke / The Japanese Journal of Rehabilitation Medicine

Objects：Sit-to-stand (STS) interventions are frequently used as part of stroke rehabilitation. This study aimed to clarify the kinematic and kinetic characteristics of patients recovering from stroke, who have difficulties with STS movement.Method：The participants included 26 stroke patients who struggled to complete the STS maneuver. Using a 3D motion analysis system, the kinematic and kinetic parameters during STS were retrospectively analyzed and compared between failed and successful trials. The kinematic parameters of the trunk and lower limbs were obtained within the seat-off phases, and the kinetic indices of the lower limbs were obtained from measurements taken before and after the seat-off phase. The weight-bearing ratio on the unaffected side was calculated from the vertical ground reaction forces.Results：In the successful trials, analyses of the parameters revealed more forward tilting of the pelvic and thoracic regions, a further forward and downward shift of the center of mass, and larger hip and knee extension moments than those of the failed trials. However, there was no difference in the weight-bearing ratio on the non-paralyzed side.Conclusion：This study revealed that the kinematic and kinetic properties of the STS maneuver differed between successful and failed trials among patients with stroke. The study therefore provides useful information for clinical evaluation and rehabilitation.

Utilização de sensores inerciais no teste timed up and go: uma revisão narrativa / Use of inertial sensors in the timed up and go test: a narrative review

O teste funcional Timed Up and Go (TUG) é amplamente utilizado para avaliar o risco de queda, através do equilíbrio e mobilidade, por ser de fácil aplicação e boa reprodutibilidade na prática clínica. Porém, o TUG ainda possui algumas limitações, pois se concentra no tempo total em que o teste é realizado. Uma proposta de avaliação é através da utilização de sensores inerciais, baseados na tecnologia de sistemas microeletromecânicos, e vem sendo muito utilizados para análise do movimento humano. Logo, o objetivo desse estudo foi realizar uma revisão narrativa sobre o uso dos sensores inerciais nas medidas temporais e cinemáticas do TUG e suas subfases. Metodologia: Essa revisão narrativa foi realizada nas bases de dados PubMed, CENTRAL, BVS e PEDro, por meio do vocabulário MeSH entre o período de maio a junho de 2020. Os critérios de inclusão foram estudos que utilizaram sensores inerciais para avaliação de medidas temporais e cinemáticas do TUG e suas subfases. Resultados: Foram incluídos 11 artigos de um total de 2305 achados. Desses, 5 utilizaram os sensores de smartphones. Não houve padronização em relação à quantidade utilizada, nem à fixação e posicionamento. Os sensores conseguiram mostrar diferenças no TUG e suas subfases nas medidas temporais e cinemáticas nos diferentes grupos avaliados. Considerações Finais: Sensores inerciais são capazes de avaliar medidas temporais e cinemáticas do TUG e de suas subfases, mostrando serem ferramentas confiáveis. Entretanto, mesmo obtendo resultados satisfatórios, necessita-se de mais estudos abrangendo uma população maior.

The Timed Up and Go (TUG) functional test is widely used to assess the risk of falling through balance and mobility since it is easy to apply and presents good reproducibility in clinical practice. However, the TUG test still has some limitations, as it focuses on the total time the test is performed. A proposal for evaluation is the use of inertial sensors, based on the microelectromechanical system technology, which has been widely used for the analysis of human movement. Therefore, the objective of this study was to carry out a narrative review on the use of inertial sensors in the temporal and kinematic measurements of TUG and its subphases. Methodology: This narrative review was carried out in the PubMed, CENTRAL, BVS, and PEDro databases using the MeSH vocabulary between the period of May to June 2020. The inclusion criteria were studies using inertial sensors to evaluate temporal and kinematic measurements of the TUG and its subphases. Results: A total of 11 articles were selected from 2305 hits. From these, five (5) used smartphone sensors. There was no standardization regarding the quantity used, nor their fixation and positioning. The sensors were able to show differences in the TUG and its subphases in the temporal and kinematic measurements in the different groups evaluated. Final Considerations: Inertial sensors are capable of evaluating temporal and kinematic measurements of the TUG and its subphases, showing that they are reliable tools. Nevertheless, although satisfactory results were obtained, further studies are needed covering a larger population.

Biomechanical Analysis of Chinese Male Cross-Country Skiers with Double Poling Technique on Uphill Terrain during Long Distance Classical Race / 医用生物力学

Objective By making biomechanical analysis of double poling (DP) technique on uphill terrain used by Chinese male cross-country (XC) skiers, to characterize biomechanical differences in DP for skiers at different levels, and determine the influence from motion techniques of skiers on their sports performance. Methods Twenty-four male XC skiers who participated in the 15 km classical race at the Beishan ski resort in Jilin, China, on Sept. 11-12, 2019 were selected in this study. On the basis of their race performance, they were divided into faster skiing group (n=12) and slower skiing group (n=12). The kinematic variables of the skiers were obtained by three-dimensional (3D) shooting, and the differences in cycle characteristics, action phases and key technique variables for skiers in two groups were analyzed. Results Faster skiers had a faster DP velocity. There was a positive correlation between swing distance and velocity. The swing distance was positively correlated with average angular velocity of elbow extension in poling phase, average angular velocity of shoulder extension in swing phase, and range of motion (ROM) of shoulder abduction. The swing distance was negatively correlated with extension of the elbow in poling phase. All the above variables showed statistical differences between faster and slower skiers. Conclusions For a long distance competition, the difference in DP velocity on uphill terrain was mainly casued by the difference in swing distance, which originated from the swing phase. Faster skier had a longer swing distance. The differences in the swing distance came mainly from the shoulder and elbow joints. Therefore, slower XC skiers in China should strengthen muscle strength of the upper limbs, especially the shoulder and elbow joint strength. More forward body leaning and larger hip and knee flexion angle at pole plant might help the skier to cover more distance.

Analysis and Diagnosis on Backhand Twist Technique of Leading Men’s Player of National Table Tennis Team / 医用生物力学

Objective To make analysis and diagnosis on backhand twist technique used by player A, who is the leading men’s player of national table tennis team, so as to provide references for improving his backhand twist technique. Methods The three-dimensional kinematics test and analysis were used. The backhand twist techniques of player A and those of player B who has good backhand twist techniques were compared by quantitative data and picture analysis. Results At the stage of swinging racket backward, the racket swing amplitude, shoulder angle and wrist angle of player A were significantly smaller than those of player B. The roll angle of trunk of player A was significantly larger than that of player B. At the stage of swinging and hitting the ball, the shoulder angle, elbow angle of player A were significantly bigger than those of player B, while the increasing amplitude of shoulder angle and elbow angle, as well as the changing amplitude in roll angle of trunk of Lin Guoyuan were significantly smaller than those of player B. At the stage of swinging racket forward, the shoulder angle and elbow angle of player A were significantly bigger than those of player B. The increasing amplitude of shoulder angle and elbow angle, as well as the roll angle of trunk and its changing amplitude of player A were significantly smaller than those of player B. Conclusions The racket swing amplitude of player A was smaller, and the distance between the racket and the ball of player A was close at the end of swinging racket backward stage. During swinging and hitting the ball stage, the hitting point was far from the body, the shoulder joint was not stable enough to support, so that the wrist was used more. The center of gravity was not enough to force forward, and the outburst power was not concentrated. At swinging racket forward stage, player A’s braking was not active enough, which affected the stability of hitting the ball. At hitting the ball stage, the torsion of the trunk was smaller, and the waist power was not concentrated. On the basis of unaffecting the forehand outburst power, player A should slightly adjust his backhand twisting technique, or appropriately increase the the racket swing amplitude and torsion of the body. In the process of hitting the ball, the sequence of outburst power was the waist, the forearm and the wrist.

Progress on in vivo ankle biomechanics based on dual fluoroscopic imaging technology / 生物医学工程学杂志

The technical deficiencies in traditional medical imagining methods limit the study of

Progress in Knee Joint Motion Analysis after Anterior Cruciate Ligament Reconstruction / 医用生物力学

Anterior cruciate ligament (ACL) deficiency is a common clinical injury that seriously affects the function of the knee. Although ACL reconstruction (ACLR) can rebuild the structure of the ACL, it does not restore the normal kinematics and dynamics of the knee. In recent years, motion analysis has been widely applied in sports science and rehabilitation. In clinics, motion analysis is mainly applied to the evaluation of clinical outcomes of the ACLR knee. It is also a scientific objective tool to assess the potential risk factors of secondary injury and early onset of osteoarthritis after ACLR. In-depth understanding of the knee functional kinematics and kinetics after ACLR will significantly improve the efficacy of current ACL deficiency treatment and rehabilitation regime. This paper reviewed studies of the knee joint motion analysis after ACLR in the past decade. The current knowledge of the ACLR knee motion from studies using optical motion capture and biplanar fluoroscopic imaging system based tracking technique was synthesized. Clinical studies have reported that regardless of the type of graft and surgical technique of the ACLR, the postoperative knee still exhibits abnormal kinematics in functional tasks, but the relationship between early-onset OA and the biomechanical changes in the ACLR knee remains unknown. Restoring the rotational stability of the knee is still one of the biggest challenges in clinical ACLR surgery. Future studies should explore the impact of ACLR on the biomechanical mechanisms of the knee joint through an appropriate research design and long-term follow-up, and help clinicians and physiotherapists to develop more effective interventions.

Proposal of accuracy analysis of indoor tracking systems in basketball / Proposta de análise de precisão de sistemas de rastreamento interno em basquetebol

ABSTRACT The development of tracking technology caused a exponentially grow-up of research into this topic. The use of standardized methodologies is useful to contrast data of different studies. On the other hand, a low-cost reference system is needed. For this reason, the main aim of the present research is the description of a specific protocol to accuracy assessment of tracking location in indoor conditions in basketball. It can resume in three steps with detailed and easily procedures in the method section. The accuracy analysis method presented can report the centimeter of accuracy in each coordinate that the tracking system measure. A standardized protocol to evaluate the location on indoor conditions in basketball will provide to the sport science professionals a useful tool to analyze the accuracy and reliability of all tracking system, being the results can compare both within and between-court.

RESUMO O desenvolvimento da tecnologia de rastreamento causou um crescimento exponencial das pesquisas sobre esse tópico. O uso de metodologias padronizadas é útil para contrastar dados de diferentes estudos. Por outro lado, é necessário um sistema de referência de baixo custo. Por este motivo, o principal objetivo da presente pesquisa é a descrição de um protocolo específico para avaliação da acurácia do rastreamento de localização em condições internas no basquete. Pode retomar em três etapas com procedimentos detalhados e fáceis na seção do método. O método de análise de precisão apresentado pode relatar o centímetro de precisão em cada coordenada medida pelo sistema de rastreamento. Um protocolo padronizado para avaliar a localização em condições internas no basquetebol fornecerá aos profissionais de ciências do esporte uma ferramenta útil para analisar a precisão e a confiabilidade de todo o sistema de rastreamento, sendo que os resultados podem ser comparados dentro e entre as quadras.

Variations in shoulder loading due to differences in the site of stepping foot contact during baseball pitching - Comparison between flat ground and mound conditions - / 体力科学

This study examined variations in shoulder loading due to differences in the site of stepping foot contact during baseball pitching, while comparing flat ground and mound conditions. Measurement was performed, involving 10 right-handed pitchers who belonged to university baseball clubs, under original flat ground and mound conditions. Pitching movements were classified into 3 categories: [normal], [narrow], and [outside]. Through 3-dimensional motion analysis using a motion capture system, the following results were obtained: 1. The pitching velocity was significantly higher in the [normal] compared with [narrow] and [outside] conditions and under the mound compared with flat ground condition. 2. The peak torque of the shoulder internal rotation was markedly lower in the [narrow] compared with [normal] condition. There were no significant differences between the [normal] and [outside] conditions or between the flat ground and mound conditions. 3. The posterior, superior, and inferior shearing forces, as well as the proximal traction force, which influence the humeral head of the shoulder, were markedly greater in the [normal] compared with [narrow] and [outside] conditions. The anterior and posterior shearing forces and proximal traction force were significantly greater under the mound compared with flat ground conditions. Based on the results, the internal rotation torque of the shoulder, as well as the shearing and traction forces influencing the humeral head of the shoulder, may vary due to differences in the site of stepping foot contact during baseball pitching and between flat ground and mound conditions. The former may also be useful to prevent pitching-related shoulder injuries.

Validity study of Coda Motion Analysis System for measuring cervical lateral flexion in normal adults / 中国骨伤

OBJECTIVE@#To investigate the validity of Coda Motion Analysis System for measuring cervical lateral flexion in normal adults in order to explore a new measuring tool for clinical and research practice.@*METHODS@#A total of 43 participants were involved in the study. Cervical range of lateral flexion were measured with Coda Motion Analysis System and "gold standard" X-ray simultaneously. The validity and agreement were assessed using the scatter diagram, the Pearson correlation coefficient and limits of agreement.@*RESULTS@#Cervical range of lateral flexion measured by Coda Motion Analysis System had no statistical differences with those measured by X-ray(>0.05). The Coda Motion Analysis System demonstrated a very good linear relation with the X-ray measurements in cervical range of right lateral flexion, left flexion and total lateral flexion, and the Pearson correlation coefficients were 0.72, 0.85 and 0.90 respectively.@*CONCLUSIONS@#Coda Motion Analysis System showed good validity for measuring cervical lateral flexion in normal adults. Because the reliability of Coda Motion Analysis System was established previously, the results of this study suggest that the system has the potential to be used to measure cervical lateral flexion in clinical and research practice.

Construcción del registro de observación para el análisis del movimiento Fundamentado en la teoría de laban1 / Development Of An Observation Instrument For Recording Movement Analysis Based On Laban's Theory / Construção do registro de observação para a análise do movimento Fundamentado na teoría de laban

Resumen Barnet-López, S., Arbonés-García, M., Pérez-Testor, S. y Guerra-Balic., M. (2017). Construcción del registro de observación para el análisis del movimiento fundamentado en la teoría de Laban. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 15(2), 1-21. En este artículo se describe el proceso de construcción de un Registro de Observación inspirado en el Análisis del Movimiento de Laban (ROAM) en personas con Discapacidad Intelectual (DI). La aplicación del ROAM permite obtener una medida objetiva y estandarizada sobre las tendencias generales de movimiento de la persona, además de poder utilizarse en observaciones pre y post intervenciones y así conocer los cambios de movimiento del individuo. El del ROAM se desarrolló en varias fases, en la primera de las cuales se identificaron los elementos básicos para el registro y se realizaron diversas versiones del ROAM mediante la técnica de jueces expertos. En las fases posteriores se realizó el estudio exploratorio, utilizando el registro para evaluar dos sesiones de danza movimiento terapia en un grupo de adultos con DI. Los resultados muestran que el ROAM presenta unos buenos índices de validez de contenido y de fiabilidad inter e intra observadores (0.72), por tanto, el ROAM permitió analizar las características generales del movimiento de las personas con DI que participaron en el estudio exploratorio.

Abstract Barnet-López, S., Arbonés-García, M., Pérez-Testor, S. & Guerra-Balic., M. (2017). Development of an Observation Instrument for Recording Movement Analysis based on Laban's Theory. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 15(2), 1-21. This paper describes the development process of an observation record inspired in Laban's Movement Analysis (ROAM) for Intellectually Disabled (ID) people. An objective and standardized measurement of a person's general movement tendencies can be obtained from ROAM, in addition to making observations before and after an intervention, therefore learning about movement changes of an individual. The design of ROAM was developed in several stages: for the first one, basic elements were identified for the record and different versions of ROAM were created using the expert judges technique. Later stages involved an exploratory study, where two sessions of movement-dance therapy were evaluated in a group of ID adults using the record. Our results show that ROAM exhibits good indexes for content validity as well as intra- and inter-observer reliability (0.72). Thus, we conclude that ROAM allowed us to analyze the general movement characteristics of intellectually disabled individuals participating in this exploratory study.

Resumo Barnet-López, S., Arbonés-García, M., Pérez-Testor, S. & Guerra-Balic., M. (2017). Construção do registro de observação para a análise do movimento fundamentado na teoría de Laban. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 15(2), 1-21. Neste artigo se descreve o processo de construção de um Registro de Observação inspirado na Análise do Movimento de Laban (ROAM) em pessoas com Deficiência Intelectual (DI). A aplicação do ROAM permite obter uma medida objetiva e padronizada sobre as tendências gerais de movimento da pessoa, além de ser possível sua utilização em observações pré e pós intervenções e assim conhecer as mudanças de movimento do indivíduo. O desenho do ROAM foi desenvolvido em várias fases, na primeira das quais se identificaram os elementos básicos para o registro e realizaram diversas versões de ROAM através da técnica de juízes peritos. Nas fases posteriores foi realizado o estudo exploratório, utilizando o registro para avaliar duas sessões de dança movimento terapia em um grupo de adultos com DI. Os resultados mostram que o ROAM apresenta alguns bons índices de validade de conteúdo e de fiabilidade inter e intraobservadores (0,72), portanto, o ROAM permitiu analisar as características gerais do movimento das pessoas com DI que participaram no estudo exploratório.

Upper extremity temporospatial parameters and kinematics of Filipino track and field paralympians during wheelchair Propulsion: An analysis using a Kinect-based markerless motion analysis system

@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> The potential of a low-cost, novel Kinect?-based markerless motion analysis system as a tool to measure temporospatial parameters, joint and muscle kinematics, and hand trajectory patterns during the propulsion and recovery phase of wheelchair propulsion (WCP) was determined.</p><p style="text-align: justify;"><strong>METHODS:</strong>Twenty (20) adult male track and field paralympians,(mean age = 36 ± 8.47) propelled themselves on a wheelchair ergometer system while their upper extremity motion was recorded by two Kinect? cameras and processed.</p><p style="text-align: justify;"><strong>RESULTS:</strong> The temporospatial parameters, joint kinematics, and hand trajectory patterns during the propulsion and recovery phase of each participant's WCP cycle were determined and averaged. Average cycle time was 1.45s ± 0.19, average cadence was 0.70 cycles/s ± 0.09, and average speed was 0.76m/s ± 0.32. Average shoulder flexion was 30.99° ± 28.38, average elbow flexion was 24.23° ± 12.25, and average wrist flexion was 12.82° ± 26.78. Eighty five percent (85%) of the participants used a semicircular hand trajectory pattern.</p><p style="text-align: justify;"><strong>CONCLUSION:</strong> The low-cost, novel Kinect?-based markerless motion analysis system had the potential to obtain measurable values during independent wheelchair propu

Imaging skills for transthoracic echocardiography in cardiology fellows: The value of motion metrics.

Background: Proficiency in transthoracic echocardiography (TTE) requires an integration of cognitive knowledge and psychomotor skills. Whereas cognitive knowledge can be quantified, psychomotor skills are implied after repetitive task performance. We applied motion analyses to evaluate psychomotor skill acquisition during simulator-based TTE training. Methods and Results: During the first month of their fellowship training, 16 cardiology fellows underwent a multimodal TTE training program for 4 weeks (8 sessions). The program consisted of online and live didactics as well as simulator training. Kinematic metrics (path length, time, probe accelerations) were obtained at the start and end of the course for 8 standard TTE views using a simulator. At the end of the course TTE image acquisition skills were tested on human models. After completion of the training program the trainees reported improved self-perceived comfort with TTE imaging. There was also an increase of 8.7% in post-test knowledge scores. There was a reduction in the number of probe accelerations [median decrease 49.5, 95% CI = 29-73, adjusted P < 0.01], total time [median decrease 10.6 s, 95% CI = 6.6-15.5, adjusted P < 0.01] and path length [median decrease 8.8 cm, 95% CI = 2.2-17.7, adjusted P < 0.01] from the start to the end of the course. During evaluation on human models, the trainees were able to obtain all the required TTE views without instructor assistance. Conclusion: Simulator-derived motion analyses can be used to objectively quantify acquisition of psychomotor skills during TTE training. Such an approach could be used to assess readiness for clinical practice of TTE.

Effects of leg length discrepancy on gait: An experimental study / 医用生物力学

Objective To simulate leg length discrepancy by unilateral increase in lower limb of normal person, analyze gait features in the case of leg length discrepancy and its effect on walking gait, so as to provide theoretical proofs for chronical musculoskeletal diseases in lower limb amputees due to leg length discrepency. Methods Leg length discrepancy was simulated by subjects wearing shoes to increase the unilateral height of one leg. The time-space parameters, ground reaction forces and joint angles of the subjects during normal walking gait and leg length discrepancy gait were obtained via the 3D motion capture system and the reaction force platform to make comparative analysis. Results Significant differences were found between leg length discrepancy gait and normal gait in terms of step length, stride time and single supporting period. In the case of leg length discrepancy gait, the ground reaction force of both feet significantly increased at heel-strike phase compared with normal gait, and obvious changes were observed in angles of hip, knee and ankle joints. Conclusions Leg length discrepancy is an important cause leading to gait abnormalities, and maybe a cause of leg joint diseases for trans-tibial amputees wearing prosthesis.

Human motion analysis: A review of its development and applications / 医用生物力学

Motion analysis is the science that quantitatively investigates human body movement. Motion analysis can help simplify human body motion when performing complex tasks, facilitate standardization of the movement and improve the efficiency of carrying out the tasks. Currently, motion analysis has been widely applied in many fields of the daily life, including medicine, sports science, rehabilitation, entertainment, etc. In clinics, motion analysis had been used in not only the diagnoses of various neuromusculoskeletal diseases and patient-specific treatment planning, but also in the evaluation of outcomes of medical devices such as orthopedic implants and rehabilitation equipment. Therefore, the development of accurate and user-friendly motion analysis techniques will greatly advance the orthopedic surgeries, rehabilitation applications, precision medicine and medical engineering research. This article briefly introduces the history of motion analysis science, typical motion capture technologies, and then discusses the clinical applications of contemporary motion analysis methods as well as its future development.

Problems in Defi ning the Angle of Shoulder Axial Rotation / The Japanese Journal of Rehabilitation Medicine

Angles of the shoulder joint are usually defined in each of the sagittal, coronal, and horizontal planes passing through the center of the shoulder joint. One of the problems with this method is the difficulty of describing some positions of the shoulder joint such as the anterolaterally elevated position. In 2005, the International Society of Biomechanics proposed a recommendation on definitions of joint coordinate systems including the shoulder based on Euler/Cardan angles, which have often been used for the purpose of research on shoulder joint movement in daily activities. With this definition, however, it still remains impossible to define the angle of axial rotation in the hanging down position. Also, Codman's paradox, the phenomenon where the rotation angle of the shoulder changes after motions without axial rotation of the arm, remains unsolved. To solve these problems, a new method to define the angle of shoulder axial rotation, the non-singular method, has been proposed. This review describes the history and the problems of the methods used to define shoulder angles, and presents this new method of definition.

Shoulder Joint Motion Analysis of Daily Living Activities Using a Global Coordinate System / The Japanese Journal of Rehabilitation Medicine

Objective : With clinical application in mind, we developed a method to measure the movement of a selected joint three-dimensionally as a conic domain (joint sinus cone). The method was applied to shoulder joint motion during daily living activities exercises in a group of hemiparetic poststroke patients. The results were compared to the exercise range of physically unimpaired persons. Methods : The subjects dressed in jackets and performed certain other tasks in a sitting position and the range of motion of the shoulder joint in three dimensions was measured using a 6-dimensional electromagnetic tracking system. Measurement results were analyzed with a plane display using a Lambert Azimuthal equal area. Results : This method was able to determine findings difficult to see with the naked eye, such as the narrow range of motion in a paralyzed shoulder joint and poor functionality also in the contralateral shoulder. Conclusion : The dressing measurement was achieved using magnetic measurement equipment. By displaying the results through a map projection it was possible to appreciate the whole range of the motion. Because this method facilitates the expression of complex joint exercise ranges, it will be useful in the analysis of daily behavior restrictions due to impairment.

Influences of lower limb muscle thickness on sprint motion in childhood / 体力科学

The purpose of this study was to determine the relationship in prepubertal children between lower limb muscle thickness, a quantitative index of lower limb muscle, and sprint motion, in order to clarify the effects of muscle mass development on sprint motion as well as differences in these effects due to sex and muscle location. Participants comprised 41 children in 8year-old (21 boys, 20 girls) in good health attending an elementary school in the city of Kitakyushu. Muscle thickness of the anterior thigh (MTa), posterior thigh (MTp), and calf (MTC) were measured using B-mode ultrasonography. Sprint abilities (sprint speed, stride length, and step frequency), kinematic indices relating to sprint motion and ground reaction force were also measured. Pearson product-moment correlation coefficients were calculated to determine relationships between measured variables. Effects of height and weight were eliminated, and stepwise multiple linear regression analysis was performed, using stride length and step frequency as dependent variables, and kinematic indices and ground reaction force as independent variables. In boys, posterior thigh muscle thickness and calf muscle thickness showed significant simple correlations with flying time/support time (FT/ST), which was selected as an explanatory variable for step frequency. However, no significant relationship was found between step frequency and sprint speed. The conclusion of these findings is that developing lower limb muscle mass affects sprint motion in 8-year-old boys, but does not directly lead to improved sprint speed. In girls, a significant relationship was found between posterior thigh muscle thickness and maximal leg swing velocity during the support phase (ωL), which was selected as an explanatory variable for step frequency, and a significant relationship was found between step frequency and sprint speed. Unlike boys, developing lower limb muscle mass in 8-year-old girls influences step frequency and is closely connected to sprint speed.