Finite element analysis of knee and ankle joint during gait based on motion analysis

Park, Sangbaek,Lee, Seungju,Yoon, Jeongro,Chae, Soo-Won Elsevier 2019 Medical engineering & physics Vol.63 No.-

<P><B>Abstract</B></P> <P>Contact pressures in the articular cartilage during gait affect injuries and the degenerative arthritis of knee and ankle joints. However, only contact forces at the knee and ankle joints during gait can be estimated by using a rigid body dynamic model. The contact pressure distribution can be obtained quantitatively for a static posture by using finite element (FE) analysis in most cases. The purpose of this study is to develop a new method to obtain the contact pressure distribution at the knee and ankle joints during gait by integrating FE analysis with rigid body dynamic analysis. In this method, a reference FE model of the lower extremity is constructed first and is then transformed to each stance phase of the gait obtained from dynamic analysis by using homogeneous transformation. The muscle forces and ground reaction force (GRF) during gait obtained from the dynamic analysis were used as loading conditions for FE analysis. Finally, the contact pressure distribution at the tibia plateau cartilage and talus cartilage were estimated at the 1st peak, mid-stance, and the 2nd peak at the same time. The present method can provide the contact pressure distribution at the knee and ankle joints over the entire gait.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A new method that integrates FE analysis with rigid body dynamic analysis is proposed. </LI> <LI> Interface program with self-written codes is developed to apply the results of motion analysis to the FE analysis. </LI> <LI> Coordinate system matching OpenSim model and FE model is performed to transform the FE model. </LI> <LI> Contact pressure distribution at the knee and ankle joints can be obtained according to the desired stance phase. </LI> </UL> </P>

요부 변성 후만증 환자의 보행 전후 골반경사각의 변화

김환정,김하용,성환일,박건영,박재국,서동욱,최원식,이한철,강종원 대한척추외과학회 2009 대한척추외과학회지 Vol.16 No.2

연구계획: 후향적 연구 연구목적: 요부 변성 후만증으로 진단받은 환자에 대하여 보행 전후 단순 방사선 검사와 보행 분석 검사를 통한 골반 경사각의 변화를 분석함으로써 그 유용성에 대하여 알아보고자 하였다. 대상 및 방법: 척추 시상면 불균형으로 진단받고 수술 받은 32명의 환자 중 다발성 압박 골절이 있거나, 척추 수술을 받은 과거력이 있는 경우, 슬관절이나 고관절의 퇴행성 질환으로 수술을 받은 경우 및 표지자를 정위치에 설치하기 어려운 고도 비만 환자를 제외한 요부 변성 후만증 18예를 대상으로 하였다. 이들 환자군의 평균 연령은 64세(56~72 세)이었고, 남자가 2명, 여자가 16명이었다. 환자들의 방사선학적 평가 및 보행 분석 검사를 시행하였다. 방사선학적 으로 골반 경사각을 측정하였고, 보행 분석 자료는 보행의 선형 지수와 운동 형상학 데이터를 구하였다. 결과: 평균 보행 속도(Walking velocity)는 80.7 cm/s로 정상군에 비교하여 65%로 크게 감소하였다. 평균 분속수 (cadence)는 108.7(steps/min, 정상의 106%), 평균 활보장(Stride length)은 89.3 cm(정상의 61%), 양발 간격(Step Width) 은 평균 11.2 cm (정상의 94%)로 측정되었고, 보행 속도 감소의 원인은 분속수가 감소해서가 아니라 환자의 활보장 이 감소하였기 때문이었다. 보행 분석 검사에서 측정한 보행 전 골 반 경사각은 평균 -1.3±8.0˚로 전방경사 8예, 후방 경사 10예 였으며, 보행 중 측정한 골반 경사각은 평균 12.5±8.2˚(14.1±8.4~10.8±8.4˚)로 전방경사가 17예, 후방경 사 1예로 측정되어 통계학적으로 의미있는 차이를 보였으며(p<0.05), 상관관계 계수는 -0.88로 매우 유의한 상관 관 계를 보였다. 결론: 비록 통계학적인 유의성은 없었지만 보행 전과 15분 보행 후 촬영한 단순 방사선 검사에서 골반이 전방으로 경 사되는 경향을 보였으며, 보행 분석 검사에서는 보행 도중 골반 신전 근육의 피로가 증가함에 따라 골반이 전방 경사 되는 것을 통계학적으로 확인할 수 있었다. 따라서 요부 변성 후만증 환자에서 골반 경사각의 동적인 변화를 보기 위 해서는 보행 분석 검사가 유용하리라 사료된다. Study Design: This is a retrospective study. Objectives: We wanted to verify the value of radiography and gait analysis to analyze the changes of the pelvic tilt before and after gait in the patients with LDK. Summary of Literature Review: Patients with lumbar degenerative kyphosis show dynamic changes that are closely associated with the motion of pelvis. Materials and Methods: We analyzed 18 lumbar degenerative kyphosis patients who didn’t have multiple vertebral compressio fractures, a past history of spinal surgery or surgery for degenerative arthritis of the knee or hip, and obesity which causes marker errors on the gait analysis. Pelvic tilt was statistically evaluated by utilizing radiographs and dynamically utilizing the gait analysis. The linear parameters of the gait cycle and the kinematic data were obtained from the gait analysis. Results: The LDK patients’ mean walking velocity was 80.7 cm/s, and it was largely decreased to 65% of the normal value. The cause of the decreased walking velocity was a decrease of stride length, and not a decrease of cadence. The mean static pelvic tilt in the gait analysis was -1.3±8.0˚, and there were 8 cases of anterior tilt and 10 cases of posterior tilt. The mean pelvic tilt during gait was 12.5±8.2˚, and there were 17 cases of anterior tilt and 1 case of posterior tilt. It was statistically significant difference (p<0.05) between the mean static pelvic tilt in gait analysis and the mean pelvic tilt during gait and the Pearson’s correlation coefficient was -0.88. Conclusions: Though there was no statistical significance, we observed anterior pelvic rotation after gait on the radiographs. As fatigue of the pelvic extensor muscles increases during gait, anterior pelvis tilt increases with statistical significance on the gait analysis. Therefore, we feel gait analysis is useful for evaluating the dynamic change of the pelvic tilt in patients with LDK.

Temporal and Spatial Gait Feature Extraction of Healthy Subjects using Principal Component Analysis

Hayoon Lee,Wiha Choi,Sehoon Oh 제어로봇시스템학회 2020 제어로봇시스템학회 국제학술대회 논문집 Vol.2020 No.10

Gait is an important human motion that is essential for performing various daily activities. Thus, gait analysis provides valuable information on the functional ability of human. However, gait is a complex motion with lots of measurements to consider during analysis. This study aims to derive latent and compound gait features of healthy subjects in temporal and spatial aspects. Force plates are used to measure ground reaction forces and moments of healthy subjects in medial-lateral, anterior-posterior, and vertical direction during stance phase. Principal component analysis (PCA), which is a method of dimension reduction, was applied to the force plate measurements to extract latent features of gait. The compound temporal and spatial gait features, which synthesize the force plate measurements, are derived from principal component analysis and their meanings are discussed using the shapes of the features. Also, the implications of principal components on gait are discussed through the comparison between the principal components and the previous studies on the force plate measurements of gait. Extraction of latent and compound gait features of healthy subjects will provide further understanding of human gait and gait analysis methods.

파킨슨병 환자에서 보행동결과 인지기능의 연관성

박희경,유종윤,이숙정,김성렬,김미정,권미선,이재홍,이명종,정선주 대한치매학회 2009 Dementia and Neurocognitive Disorders Vol.8 No.1

Background: Freezing of gait (FOG) in Parkinson’s disease (PD) is a unique motor symptom, representing the breakdown of essential components of gait. We aimed to study the correlation between FOG and cognitive functions, particularly focusing on frontal and parietal functions, in patients with PD. Methods: We prospectively studied 25 patients with PD, including 15 PD patients with freezing (PDF) and 10 PD patients without freezing (PDNF). Gait analysis was performed with 3-dimensional gait analysis system that includes six cameras. The frequency of freezing episodes per one cycle, total step numbers per one cycle, and total time of one gait cycle were evaluated. All patients were evaluated with K-MMSE, Montreal Cognitive Assessment-Korean (MoCA-K), and Rey Complex Figure Test (RCFT). Results: In PDF, there was significant improvement in total step number, total time, gait velocity, cadence, and stride length after using visual cue. For auditory cue, in PDF, there was significant improvement in total step number, total time, freezing number, and cadence. FOG in PD was associated with some aspects of frontal dysfunction. However, there was no significant correlation between gait features and other cognitive tests, including total scores of K-MMSE, MoCA-K, and RCFT, in both PDF and PDNF. Conclusions: FOG in PD was significantly improved by external cues. FOG in PD was associated with some aspects of frontal dysfunction, which warrants for further investigations in detail. Background: Freezing of gait (FOG) in Parkinson’s disease (PD) is a unique motor symptom, representing the breakdown of essential components of gait. We aimed to study the correlation between FOG and cognitive functions, particularly focusing on frontal and parietal functions, in patients with PD. Methods: We prospectively studied 25 patients with PD, including 15 PD patients with freezing (PDF) and 10 PD patients without freezing (PDNF). Gait analysis was performed with 3-dimensional gait analysis system that includes six cameras. The frequency of freezing episodes per one cycle, total step numbers per one cycle, and total time of one gait cycle were evaluated. All patients were evaluated with K-MMSE, Montreal Cognitive Assessment-Korean (MoCA-K), and Rey Complex Figure Test (RCFT). Results: In PDF, there was significant improvement in total step number, total time, gait velocity, cadence, and stride length after using visual cue. For auditory cue, in PDF, there was significant improvement in total step number, total time, freezing number, and cadence. FOG in PD was associated with some aspects of frontal dysfunction. However, there was no significant correlation between gait features and other cognitive tests, including total scores of K-MMSE, MoCA-K, and RCFT, in both PDF and PDNF. Conclusions: FOG in PD was significantly improved by external cues. FOG in PD was associated with some aspects of frontal dysfunction, which warrants for further investigations in detail.

가상현실환경에서 정상성인의 거울보행이 보행특성에 미치는 영향

이재호 대한통합의학회 2022 대한통합의학회지 Vol.10 No.3

Purpose : The study aims to see the effects of virtual reality and non-virtual reality in a normal person’s mirror walk on gait characteristics. Methods : Twenty male adults (Age; 27.8±5.8) took part in the study. The subjects attached reflection markers for motion analysis, and walked aware of the virtual reality environment with mirrors wearing goggles showing them virtual environments. After gait in a virtual environment, the subjects walked in a non-virtual environment with mirrors a certain distance away after taking a five minute break. To prevent the order effect cause by the experiential difference of gait order, ten subjects were chosen randomly into groups and the order was differentiated. In each gait, infrared camera was used to detect motion and the position of the markers were saved real time. Results : Comparison between virtual and non-virtual reality mirror walks showed that the movable range of leg joints (ankle, knee and hip joint), body joints (sacroiliac, atlantoaxial joint), arm joints (shoulder, wrist joint) showed meaningful differences. Temporal characteristics showed that virtual gaits speed were slower, and the cycle time and double limb support time of the gaits were longer. Furthermore, spacial characteristics showed that virtual gaits were shorter in steps length and strides length, the stride width longer and center of movement horizontally longer. Conclusion : The reduction in joint movement in virtual reality is due to adverse effects on balance and efficiency during gait. Also, the change in temporal-spatial characteristics of gait would be due to change in gait mechanisms for balance, showing that virtual gaits are more demanding than the other. However, the subject group is a normal group with no abnormality in gait ability and balance ability, and it is not clear whether the decrease in performance is the result of environment or fear. Therefore it is necessary to understand whether the subject group's improvement and fear affect the result in future studies.

The comparison of joint kinematic error using the absolute and relative coordinate systems for human gait

임용훈,최안렬,민경기,금동혁,최창현,문정환,이상식 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.1

Minimizing artifacts from skin movement is vital for acquiring more accurate kinematic data in human movement analysis. There are several stages that cause skin movement artifacts and these stages depend on the selection of the reference system, the error reduction method and the coordinate system in clinical gait analysis. Due to residual errors, which are applied to the Euler and Bryant angle methods in each stage, significant cumulative errors are generated in the motion analysis procedure. Thus, there is currently a great deal of research focusing on reducing kinematic errors through error reduction methods and kinematic error estimations in relation to the reference system. However, there have been no studies that have systematically examined the effects of the selected coordinate system on the estimation of kinematic errors, because most of these previous studies have been mainly concerned with the analysis of human movement using only the human models that are provided in the commercial 3D motion capture systems. Therefore, we have estimated the differences between the results of human movement analyses using an absolute coordinate system and a relative coordinate system during a gait, in order to establish which system provides a more accurate kinematic analysis at the ankle joint. Six normal adult subjects with no neurological or orthopedic conditions, lower extremity injuries, or recent history of lower extremity surgery were used in this study. The analysis was conducted at a walking speed of 1.35m/s. For the clinical estimation, we used a cardinal plane based on the segmental reference system and the differences were plotted on the planes. From this analysis, when a relative coordinate system was in the gait analysis, the average kinematic error occurring during the gait was determined to be 13.58mm, which was significantly higher than the error generated with an absolute coordinate system. Therefore, although the relative coordinate system can also be used to calculate the ankle joint center during the clinical gait analysis, the absolute coordinate system should be employed in order to obtain more accurate joint kinematic data. In addition, the results from this study can be used as a basis to select an appropriate coordinate system with regards to the diagnostic accuracy level required for various kinds of gait disorders.

A Gait Analysis Using Smart Phone Images of the Knee Joint Angle and Stride Length

J. H. Jang(장재훈),C. J. Lim(임창주),K. H. Song(송기호),S. T. Chung(정성택) 한국재활복지공학회 2013 재활복지공학회논문지 Vol.7 No.2

다양한 신경계 및 근골격계 질환이 있을 때 나타나는 증상으로 보행변화가 일어나며, 이에 대한 보행분석은 병의 진행 정도를 판단하는 데 매우 중요하다. 대부분의 보행분석 방법으로는 고가의 장비 사용과 공간의 제약을 받고 있다. 본 연구는 스마트 폰을 이용한 촬영 영상과 보행궤적 분석 프로그램을 사용하여, 보행 시 슬관절 각도의 변화와 활보장 측정을 바탕으로 보행분석을 진행하였다. 보행분석에 필요한 실험은 건강한 성인남성 7명을 대상으로 진행하였으며, 오른쪽 및 왼쪽 무릎관절 각도 및 활보장에 대한 데이터를 이용하여 보행분석이 이루어졌다. 본 연구에서 얻어진 보행분석은 기존의 보행분석 연구들과 비교하여 유사한 결과를 획득하였다. 여기서 제안한 방법을 이용한다면 고가의 장비와 공간의 제약없이 보행 분석을 할 수 있을 것이다. Various types of disease in the nervous and musculoskeletal system can change gait, and the gait analysis is very important in determining the progression of the disease. Most methods of analyzing gait are subject to high-priced equipment and spatial restrictions. This study used smart phone images and the walking track analysis program to make a comparative analysis with the existing gait analysis on the basis of the stride length measurements and the changes in the knee joint angle for walking. The test necessary to analyze gait was conducted in seven healthy men, and data about the angle of right and left knee joints and stride length were used to analyze gait. The gait analysis in this study obtained the similar results to the existing ones. The use of the methods suggested in this study will enable gait analysis to be made without high-priced equipment and spatial restrictions.

스마트폰 영상을 이용한 슬관절 각도 및 활보장에 대한 보행분석

장재훈,임창주,송기호,정성택 한국재활복지공학회 2013 재활복지공학회논문지 Vol.7 No.2

Various types of disease in the nervous and musculoskeletal system can change gait, and the gait analysis is very important in determining the progression of the disease. Most methods of analyzing gait are subject to high-priced equipment and spatial restrictions. This study used smart phone images and the walking track analysis program to make a comparative analysis with the existing gait analysis on the basis of the stride length measurements and the changes in the knee joint angle for walking. The test necessary to analyze gait was conducted in seven healthy men, and data about the angle of right and left knee joints and stride length were used to analyze gait. The gait analysis in this study obtained the similar results to the existing ones. The use of the methods suggested in this study will enable gait analysis to be made without high-priced equipment and spatial restrictions. 다양한 신경계 및 근골격계 질환이 있을 때 나타나는 증상으로 보행변화가 일어나며, 이에 대한 보행분석은 병의 진행 정도를 판단하는 데 매우 중요하다. 대부분의 보행분석 방법으로는 고가의 장비 사용과 공간의 제약을 받고 있다. 본 연구는 스마트 폰을 이용한 촬영 영상과 보행궤적 분석 프로그램을 사용하여, 보행 시 슬관절 각도의 변화와 활보장 측정을 바탕으로 보행분석을 진행하였다. 보행분석에 필요한 실험은 건강한 성인남성 7명을 대상으로 진행하였으며, 오른쪽 및 왼쪽 무릎관절 각도 및 활보장에 대한 데이터를 이용하여 보행분석이 이루어졌다. 본 연구에서 얻어진 보행분석은 기존의 보행분석 연구들과 비교하여 유사한 결과를 획득하였다. 여기서 제안한 방법을 이용한다면 고가의 장비와 공간의 제약없이 보행 분석을 할 수 있을 것이다.

임상 물리치료사의 경험에 따른 시각적 보행 분석의 신뢰도 연구

이인희,Lee, In-Hee 대한물리치료학회 2013 대한물리치료학회지 Vol.25 No.4

Purpose: Visual gait analysis plays a pivotal role in determining the important gait problem of patients. A few studies have been published and have received little attention regarding visual gait analysis on patients with orthopedic problems. The purposes of this study were to investigate the difference of reliability levels according to experience of clinical physical therapists. Methods: Thirty-five clinical physical therapists, 5 high experienced, 15 experienced, and 15 inexperienced, were recruited and individually evaluated these videotaped gait patterns of the participants, and filled up the structured gait analysis form. The gait of nine participants was videotaped. Reliability levels were calculated by the Intraclass Correlation Coefficients (ICC). Results: The inter-rater reliability of high experienced group (ICC=0.56; 95% CI: 0.50-0.62) was comparable to that of the experienced raters (ICC=0.48; 95% CI: 0.43-0.53) and inexperienced group (ICC=0.42; 95% CI: 0.38-0.46). High experienced group reached a higher inter-rater reliability level. The average intra-rater reliability of the high experienced group was 0.70 (ICCs ranging from 0.54 to 0.82). The experienced group reached an average intra-rater reliability of 0.61 (ICCs ranging from 0.47 to 0.81). The inexperienced group attained average ICC values of 0.53 (ICCs ranging from 0.30 to 0.74). Conclusion: Use of a structured gait analysis form as described in this study was found to be moderately reliable. Clinical experience appears to increase the reliability of visual gait analysis.

정상 성인의 운동역학적 보행분석

김건,윤나미,Kim, Geon,Yoon, Na-Mi 대한물리치료학회 2009 대한물리치료학회지 Vol.21 No.2

Purpose: This study reports the basic reference data of the specific gait parameters for Korean normal adults. Methods: The basic gait parameters were extracted from 73 Adults (35 men and 38 women), 18 to 33 years of age, using a Vicon MX motion analysis system. The segment kinetics, such as joint moment and power, was analyzed at the hip, knee and ankle. Results: The motion patterns are typically associated with a specific phase of the gait cycle. The temporal-spatial gait parameters of Korean normal adults, such as cadence, walking speed, stride length, single support and double support, were similar to the other western reference data. The kinetic parameters of Korean normal adults, such as joint moments of force, joint mechanical power generation or absorption and ground reaction forces, were also similar to other western reference datasets. Conclusion: This study demonstrates that objective gait analysis can be used to document the gait patterns of normal healthy adults. The techniques of 3-dimensional temporal-spatial gait parameters and kinematic parameters analysis can provide a detailed biomechanical description of a normal and pathological gait.