Gait & posture最新文献

{"title":"Investigation of the knee angular velocity proprioceptive behavior as the joint velocity increases","authors":"Ioanna Katsaveli, Anthi Kellari, Zacharias Dimitriadis, Ioannis Poulis, Asimakis Kanellopoulos","doi":"10.1016/j.gaitpost.2023.07.116","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.116","url":null,"abstract":"Proprioception plays a crucial role to coordinated movement, which is fundamental for daily activities, exercise, and sports. The proprioceptive perception of joint angular velocity sense has received little attention in terms of research, unlike joint position sense, which has been thoroughly studied (1). The present research was conducted in order to investigate the behavior of the proprioceptive ability to comprehend and reproduce low-to-medium angular velocities in the knee joint in a healthy population. The investigation of the proprioceptive behavior regarding the accuracy of the knee joint angular velocity replication, in different joint angular velocities. 43 young healthy individuals (23 men and 20 women, mean age 20.84 yrs) participated in the present research, and were measured in 5 angular joint velocities, 30o/s, 45o/s, 60o/s, 75o/s and 90o/s, and in a randomized order, by using the “Biodex System 3 pro” isokinetic dynamometer. Five passive demonstration trials were followed by five active replications. The subjects were blindfolded during the whole procedure and they were blinded to the results, as were the examiners. Only the last 3 replication attempts were used to calculate the average velocity achieved, since the first two were considered as familiarization trials. The subjects appear to have reproduced the angular velocity of 30o/s more accurately. There is a statistically significant error in the replication of the rest of the velocities, incrementally increasing as the joint angular velocity increased. The lowest angular velocity of 30o/s showed the less significant replication error, both in absolute value (6.0o/s) and as a percentage (20.0%) of the targeted velocity, while 90o/s had the biggest one (34.9o/s and 38.8%, respectively). Something noteworthy was that the majority of the volunteers tend to undershoot the target velocities. Specifically, the number of subjects that undershoot (in comparison to the sample size) were 28/43, 38/43, 40/43, 41/43 and 43/43 for 30o/s, 45o/s, 60o/s, 75o/s and 90o/s respectively. The present study showed that as the joint angular velocity increases, and the brain cannot be informed on time about the joint motion state and is forced to predict it, the replication error increases. Regarding the unknown in the literature undershooting phenomenon observed in the present study, it seems that as the joint velocity increases and cannot be predicted with accuracy, the brain, from the spectrum of the possible predicted ones, always choses to replicate it with one of those with the lower values. This phenomenon may be an interesting conservative behavior of the brain, as the high joint angular velocities seem to be related with injuries.","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"“I’d go slow and hope I don’t fall” Exploring lived experiences of children with cerebral palsy walking in challenging environments","authors":"Rebecca Louise Walker, Thomas D O'Brien, Gabor J Barton, Bernie Carter, David M Wright, Richard J Foster","doi":"10.1016/j.gaitpost.2023.07.263","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.263","url":null,"abstract":"Children with cerebral palsy (CwCP) experience regular falls [1] but their lived experiences of how falls occur in the real-world are unknown. Understanding real-world causes of falls by listening to perspectives of children and parents is vital, since typical walking analyses are carried out over level-ground and therefore overlooks everyday challenges to balance [2]. Walk-along interviews can generate rich insights into children’s everyday life by discussing experiences while walking [3]. This abstract presents findings from ‘The Walk-Along Project’, a novel qualitative investigation using walk-along interviews to explore lived experiences of CwCP. The Walk-Along Project aimed to determine the challenging walking environments (e.g. uneven surfaces) that increase fall-risk. What types of challenging environments affect fall-risk in CwCP, based on their lived experiences? Twelve CwCP (GMFCS I to III, 6 diplegia, 6 hemiplegia, 12±3 years old) and their parents participated in an outdoor walk-along interview lasting approximately 25 minutes. During each walk-along interview participants discussed previous fall experiences and everyday ‘challenging’ environments (likely to cause a fall) that they commonly encounter. Chest-mounted cameras (Kaiser Baas X450) and clip on microphones (RODE GO II) captured walking environments and conversations. Data from microphones were matched to video footage, manually transcribed and analysed in NVivo using interpretive description[4]. Environments that could or have previously caused a fall were identified by CwCP and photographed during walk-along interviews (Fig. 1). Any uneven surface that could cause a trip or balance disturbance was suggested as challenging, such as tactile paving: “I’d probably trip over it because it is bumpy” (child, aged 13) Unseen grass potholes were reported to cause most falls based on past experiences. Falls were also more likely when combined with sensory distractions (e.g. seeing/hearing nearby people/friends): “So like if I am walking in this direction and am looking at [people playing nearby] football I could go like that…[demonstrates trailing foot tripping on a raised grid]” (child, aged 16) Download : Download high-res image (167KB)Download : Download full-size image Children described things they do to reduce fall-risk, including being careful, avoiding places or walking slower: “I would just go slow on a grass surface and hope that I don’t fall” (Child, aged 8) Younger children evidenced receiving more parental intervention when walking in challenging environments (e.g. “watch your step”). In comparison, older children reported having better awareness of what could cause a fall compared to when they were younger. The Walk-Along Project provides novel insight beyond what is currently known about the types of challenging environments that increase fall-risk in CwCP. Both environmental (uneven surfaces) and sensory (everyday distractions) challenges contribute heavily to daily fa","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of the number of labelled frames on the accuracy of 2D markerless pose estimation (DeepLabCut) during treadmill walking","authors":"Maud Van Den Bogaart, Maaike M. Eken, Rachel H.J. Senden, Rik G.J. Marcellis, Kenneth Meijer, Pieter Meyns, Hans M.N. Essers","doi":"10.1016/j.gaitpost.2023.07.254","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.254","url":null,"abstract":"Gait analysis is imperative for tailoring evidence-based interventions in individuals with and without a physical disability.1 The gold standard for gait analysis is optoelectronic three-dimensional motion analysis, which requires expertise, is laboratory based, and requires expensive equipment, which is not available in all settings, particularly in low to middle-income countries. New techniques based on deep learning to track body landmarks in simple video recordings allow recordings in a natural environment.2,3 Deeplabcut is a free and open-source toolbox to track user-defined features in videofiles.4,5 What is the minimal number of additional labelled frames needed for good tracking accuracy of markerless pose estimation (DeepLabCut) during treadmill walking? An increasing number of videos (1, 2, 5, 10, 15 and 20 videos) from typically developed adults (mean age = 50.7±17.3 years) were included in the analysis. Participants walked at comfortable walking speed on a dual-belt instrumented treadmill (Computer Assisted Rehabilitation Environment (CAREN), Motekforce Link, Amsterdam, The Netherlands). 2D video recordings were conducted in the sagittal plane with a gray-scale camera (50 Hz, Basler scA640-74gm, Basler, Germany). Using the pre-trained MPII human model (ResNet101; pcut-off = 0.8) in DeepLabCut, the following joints and anatomical landmarks were tracked unilaterally (left side): Ankle, knee, hip, shoulder, elbow and wrist (chin and forehead were excluded). An increasing number of frames was labeled per video (1 and 5 frames per video) and added to the pre-trained MPII human model, which was then retrained till 500.000 iterations. 95% of the labelled frames were used for training, 5% for testing. For each scenario with an increasing number of videos and manually labelled frames, the train and test error was calculated. Good tracking accuracy was defined as an error smaller then the diameter of a retroreflective marker (= 1.4 cm). The results of the train and test pixel errors are presented in Fig. 1 for 11 different scenarios. When the number of videos increased to 5 videos with 1 or 5 labelled frames, the train pixel error reduced to 1.11 and 1.16 pixels, respectively (corresponding to an error of < 1 cm). From labelling at least 20 frames, the test pixel error was less then 5 pixels (corresponding to an error of < 3 cm).Download : Download high-res image (91KB)Download : Download full-size image A good tracking accuracy (error < 1 cm) in the training set was achieved from 5 additionally labeled videos. The tracking accuracy for the test dataset remained constant (≈ 2-3 cm) from labelling 20 frames or more. Further research is needed and ongoing to determine the optimal number of training iterations and additional labelled videos and frames for good test and train tracking accuracy (< 1.4 cm). This optimal setup will then be used to validate DeepLabCut to measure joint centres and angles during walking with respect to the gold standard.","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Delphi Process is being applied to objectify the systematic use of EMG in therapy of Cerebral Palsy","authors":"Robert Reisig, Mehrdad Davoudi, Marco Götze, Firooz Salami, Sebastian Wolf","doi":"10.1016/j.gaitpost.2023.07.208","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.208","url":null,"abstract":"Cerebral Palsy (CP) is a neurodevelopmental disorder that affects motor function and coordination. While there is no curative treatment, various methods, surgical and conservative, can be used to optimize patients' physical performance. [1] Treatment planning involves physical examination, imaging, and gait analysis. [2] Despite being the only method apart from physical examination to assess muscle weakness and spasticity, the role of EMG data in decision-making is little understood. [3] However, it can be efficient to perform and could substantially improve treatment decision trees. [4] This Delphi Process complements a data driven approach with identical research goals so that findings of both can be integrated. How can EMG enhance diagnostic and therapeutic methods for patients with CP? Our objectives include identifying key EMG data features that advance decision-making processes and determining the most appropriate and impactful descriptors for data evaluation. Additionally, present-day utilization is being investigated. A Delphi Process is being employed, engaging an initial panel of 53 experts in gait analysis. Of these, 44 have agreed to continue their participation in the project. These experts were selected based on their affiliation with ESMAC and referrals from other participants. In the first round, panelists were asked about their current or past use of EMG in gait analysis for patients with CP. Questions covered the topics effectiveness, reliability, assessed muscles, data processing, decision-making processes involving EMG data, use of normative data, and descriptors being used to evaluate EMG. Participants will receive the evaluated results from the previous rounds and may base their decisions on this information. The second round is scheduled to begin by the end of April 2023. The third round is planned for completion and evaluation before ESMAC in September 2023. The Delphi Process is currently underway, and the first round has been completed. 90% of participants found EMG information in the context of CP to be at least somewhat helpful, and 79% considered it at least somewhat reliable. While at least 32% of participants rely solely on raw data, more than 21% solely use enveloped data. The muscles predominantly used for decision processes are rectus femoris and tibialis anterior. Statistic assessed musclesDownload : Download high-res image (86KB)Download : Download full-size image The most widespread descriptors used include 'delayed,' 'prolonged,' 'premature,' 'cocontraction,' 'out of phase,' 'absent,' 'early' and 'continuous. Current results show predominant consensus about helpfulness and reliability of EMG data in the context of CP. Simultaneously, there seem to be two major approaches in data evaluation – one using raw data and the other using envelopes. In future rounds of the process we aim to collect treatment decision trees from experts which are based on EMG data – may they be driven by experience or evidence – and tr","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Movement tracking and action classification for human behaviour under threat in virtual reality","authors":"Ulises Daniel Serratos Hernandez, Jack Brookes, Samson Hall, Juliana K. Sporrer, Sajjad Zabbah, Dominik R. Bach","doi":"10.1016/j.gaitpost.2023.07.230","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.230","url":null,"abstract":"Understanding and characterising human movements is complex due to the diversity of human actions and their inherent inter, intra, and secular variability. Traditional marker-based, and more recently, some marker-less motion capture (MoCap) systems have demonstrated to be reliable tools for movement analysis. However, in complex experimental set ups involving virtual reality (VR) and free movements (as in [1]), accuracy and reliability tend to decrease due to occlusion, sensor blind spots, marker detachment, and other artifacts. Furthermore, when actions are less distinct, e.g., fast walk and slow run, current classification methods tend to fail when actions overlap, which is expected as even researchers struggle to manually label such actions. Can current marker-less MoCap systems, pose estimation (PE) algorithms, and advanced action classification (AC) methods: (1) accurately track participant movements in VR; (2) cluster participant actions. The experiment consisted of avoiding threats (Fig. 1A) whilst collecting fruit in VR environments (n=29 participants, 5x10m area), see [1]. The Unity® software [2], based on the Unity Experiment Framework [3], was used to create the VR experiment, which was streamed through an HTC vive pro (HTC Corporation) VR headset. Movements were recorded using 5 ELP cameras (1280×720 @120 Hz) synchronised with the Open Broadcaster Software® (OBS) [4]. Openpose [5] was employed for PE (Fig. 1B). Euclidean distances, and angular positions, velocities, and accelerations were derived from cartesian positions. Finally, Uniform Manifold Approximation and Projection (UMAP) was used to embed high-dimensional features into a low-dimensional space, and Hierarchical Density Based Spatial Clustering of Applications (HDBSCAN) was used for classification (see Fig. 1E), similar to B-SOiD [6]. Participants were virtually killed by the threat in 223 episodes, for which the participants’ last poses were estimated. After applying UMAP and HDBSCAN, 5 pose clusters were found (see Fig. 1C-D), which depict: (a) stand up, picking fruit with slow escape; (b) stand up, arms extended and slow escape; (c) long retreat at fast speed; (d) short retreat at medium speed; (e) crouching and picking fruit; (x) 4% unlabelled. Fig. 1. (A) VR-threat, (B) Participant estimated 3D-pose, (C) Pose clusters, (D) Cluster examples, (E) Methodology.Download : Download high-res image (176KB)Download : Download full-size image Marker-less MoCap and PE methods were mostly successful for participants’ last poses. However, in some cases, and during exploration, tracking was lost due to occlusion and sensor blind spots. The results from the AC methods are an indication of the potential use of unsupervised methods to find participant actions under threat in VR. Nevertheless, such clustering is rather general, and had some AC errors, which could not be quantified as further work is needed to understand and define where the threshold of overlapping actions occurs. The re","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validity and reliability of the portable Kforce plates system with the use of a smartphone application for measuring countermovement jump","authors":"George Plakoutsis, Dimitrios Zapantis, Eirini-Maria Panagiotopoulou, Eleftherios Paraskevopoulos, Maria Papandreou","doi":"10.1016/j.gaitpost.2023.07.201","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.201","url":null,"abstract":"Physical fitness is of great importance to several sports and also, in the context of public health. Several training methods such as plyometric jump training are routinely used by athletes for promoting performance. The countermovement jump (CMJ) is one of the most implemented method for testing lower limb mechanical abilities. The purpose of the present study was to examine the validity and reliability of the KForce plates system with the concurrent use of 'My Jump 2' application for measuring CMJ. Is KForce plates system a valid and reliable tool for measuring CMJ? Thirty-four collegiate athletes, twenty-two males and twelve females (age=21.6±5.7), volunteered to participate in the present study. Each participant performed three maximal CMJs while standing on a portable force platform. The jumps were recorded with a portable KForce plates system and a concurrent validated application ‘My Jump 2’ through iPhone 13 at the same time. Each participant repeated the testing procedure after seven days in order to assess the reliability of the measurements (ICC). Systematic bias between sessions and tools was evaluated using paired t-test and Bland-Altman analysis. High test-retest reliability (ICC > 0.87) was observed for all measures (jump height and jump time) in-between conditions. Very large correlations in the sample were observed between KForce plates system and My Jump 2 app for CMJ (jump height, r = 1.000, p = 0.001) and CMJ (jump time, r = 0.999, p = 0.001). The Bland-Altman’s plot illustrates limits of agreement between KForce plates system and My Jump 2 app where the majority of the data are within the 95% CIs. The results of the current study suggest that the KForce plates system was proven a valid and reliable tool for measuring jump performance in physically active adults.","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of two different exercise programs on gait in children with scoliosis diagnosed Juvenile Idiopathic Arthritis","authors":"Eylül Pınar Kısa, Gökçe Leblebici, Ela Tarakcı, Özgür Kasapçopur","doi":"10.1016/j.gaitpost.2023.07.126","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.126","url":null,"abstract":"","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association between the occurrence of falls and winning and losing in the final tournament of wheelchair basketball at Paralympic games","authors":"Rami Mizuta, Noriaki Maeda, Junpei Sasadai, Reia Shimizu, Akira Suzuki, Makoto Komiya, Kazuki Fukui, Tsubasa Tashiro, Shogo Tsutsumi, Yukio Urabe","doi":"10.1016/j.gaitpost.2023.07.158","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.158","url":null,"abstract":"Falls occur frequently in wheelchair basketball games [1]. A fall during a game not only increases the risk of injury but can also delay the player's participation in the next play, which will affect the outcome of the game. This study aimed to explore the relationship between falls and winning or losing in wheelchair basketball games, and to clarify the importance of fall prevention. Is there a relationship between the number or the situation of falls occurring in wheelchair basketball competitions and the winning/losing of games? This study was a cross-sectional video analysis study. We watched official match videos of the Tokyo 2020 Paralympic wheelchair basketball final tournament and analyzed the occurrence of falls in a total of 20 games [2]. The analysis items included the number of falls, the classification of the faller, playing time when falling, playing phase, contact with another player, foul judgement, location of the fall, shooting motion, ball retention, and time passing after a fall. Then, we classified the falls into two groups: falls that occurred in the winning team and the losing team. The number of falls was compared between the winning and losing teams, and the analysis items were compared between the groups using chi-square tests and cross-tabulation tables. The significance level was set at 0.05. Table 1 showed the results of the comparison of fall situation characteristics in winning teams and losing teams. A total of 326 falls were observed, of which 138 occurred on the winning teams and 188 on the losing teams. There was a significant difference between winning and losing teams in the classification of fallers (p=0.005). Also, a significant difference was found in the playing time of the game when falls occurred (p=0.024). There were no significant differences between the winning and losing teams in the other items related to fall situation. This study is the first report to clarify the relationship between the occurrence of falls in wheelchair basketball and the winning and losing of a game. Falls of 4-4.5 players, with relatively good trunk control [3], occurred twice as often in the losing team as in the winning team. Then, the number of falls of the losing team increased in the latter half of the game. The occurrence of many falls in the losing team may be related to their lack of chair work skills in the 4-4.5 classification to avoid falls, and physical factors such as fatigue. While falls need to be prevented in all players and situations, this study indicated the need to address fall prevention to win games, especially in the 4-4.5 classification and in the latter half of the game.","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A reference frame alignment method for the consistent interpretation of kinematic signals","authors":"Ariana Ortigas Vasquez, William R. Taylor, Barbara Postolka, Pascal Schütz, Allan Maas, Matthias Woiczinski, Thomas M. Grupp, Adrian Sauer","doi":"10.1016/j.gaitpost.2023.07.187","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.187","url":null,"abstract":"Kinematic analysis involves calculating signals from optical/inertial datapoints to represent the relative movement of joint segments. The exact choice of local segment frame orientation and position has been shown to drastically influence the shape and magnitude of the associated kinematic signals, making the consistent interpretation of the underlying motion a challenge [1,2]. Despite attempts to standardise the reporting of these signals [3], a lack of consensus around joint coordinate frame definitions remains. An approach capable of accommodating different analytical methods and reconciling these differences in frame alignment, while ensuring consistent interpretations, is therefore crucial. Given sets of kinematic data, can mathematical optimisation be leveraged to achieve a consistent interpretation of the underlying movement patterns, independent of joint axis definitions? Here, we assess a REference FRame Alignment MEthod (REFRAME) on the in vivo moving-fluoroscopy-based knee kinematics of 10 healthy subjects (5 trials of stair descent each) [4]. Using three methods of defining the flexion/extension axis (cylindrical axis (CA), functional flexion axis (FFA), and transepicondylar axis (TEA)), three different femoral frames were defined for each trial, in addition to a single tibial frame [1]. Rotations of the tibia relative to the femur were calculated, alongside translational positions of the femoral origins in the tibial frame. By implementing REFRAME (as a constrained nonlinear minimisation of ab/adduction and int/external rotation root-mean-square, in addition to all translation variances), local frames were repositioned and reorientated, to derive a set of \"REFRAMEd\" signals. Fig. 1 - Knee kinematics (rotations[°]: tibia relative to femur; translations[mm]: femur relative to tibia) during a sample stair descent trial, using three different primary axes, before (raw) and after REFRAME. (CA and FFA partially covered by TEA) Download : Download high-res image (294KB)Download : Download full-size image Across all subjects and trials, before REFRAME implementation, the maximum absolute differences between kinematic signals representing the same underlying movement, but derived using different joint axis approaches, reached 1.61° for flexion/extension, 12.00° for ab/adduction, and 12.02° for int/external rotation, in addition to 2.28 mm for mediolateral, 10.60 mm for anteroposterior, and 12.23 mm for proximodistal translations. After REFRAME, maximum differences peaked at 0.78°, 0.08° and 0.08° for flexion/extension, ab/adduction and int/external rotation, respectively; For translations, values peaked at 0.24 mm, 0.10 mm and 0.13 mm in the mediolateral, anteroposterior and proximodistal directions. Moreover, the three signals converged after REFRAME optimisation (Fig1). For each underlying movement pattern, the analysis approach (method of axis definition) affected the characteristics of the kinematic signals. By implementing REFRAME, tibi","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135298854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Idiopathic clubfoot patients produce less ankle power during hopping when compared to typically developing children","authors":"Saskia Wijnands, Lianne Grin, Lianne van Dijk, Arnold Besselaar, Marieke van der Steen, Benedicte Vanwanseele","doi":"10.1016/j.gaitpost.2023.07.268","DOIUrl":"https://doi.org/10.1016/j.gaitpost.2023.07.268","url":null,"abstract":"Idiopathic clubfoot patients show deviations in their gait patterns and other motor activities [1–4]. One of the most challenging motor activities for clubfoot patients is hopping on one leg [4–6]. Difficulty with one-leg-hopping might result from limitations in ankle mobility and plantarflexor force production in clubfoot patients [7]. This hypothesis has however not yet been investigated with detailed three-dimensional motion analysis. What are the differences in ankle power and mobility during walking and one-leg-hopping in clubfoot patients and typically developing children of 5-to-9 years old? Motion analysis was performed in 14 typically developing children (TDC) and 15 Ponseti- treated clubfoot patients of 5-to-9-year-old. Motion analysis during walking and one-leg-hopping was performed using an extended Helen-Hayes model. Spatiotemporal, kinematic, and kinetic data was collected using two integrated force plates (AMTI OR6-7) and four cameras (Codamotion CX1). For clubfoot patients, data from the most affected leg and for TDC, data from the preferred leg was used for further processing. Stride and hop length were calculated based on heel marker displacement, which was divided by stride and hop time to provide velocity. Average group data was computed for TDC and clubfoot patients, and compared using Mann-Withney U tests (p<0.05). Data from one clubfoot patient was excluded from the data analysis of one-leg-hopping, as the patient was unable to perform consecutive hops. No differences were found in spatiotemporal, kinematic, and kinetic parameters during walking between TDC and clubfoot patients (Table 1). During one-leg-hopping, however, differences were found between clubfoot patients and TDC (Table 1). Clubfoot patients showed lower peak ankle power generation (4.25 ± 1.46 W/kg) and absorption (4.65 ± 2.47 W/kg). Furthermore, clubfoot patients showed a lower peak ankle moment (1.60 ± 0.49 N/kg) and a lower velocity during one-leg-hopping. Also, a trend where clubfoot patients showed a smaller hop length was observed (p = 0.085). No differences were found in ankle range of motion during hopping.Download : Download high-res image (164KB)Download : Download full-size image During one-leg-hopping, clubfoot patients absorbed and generated less power at the ankle joint when compared to TDC. These results might indicate that clubfoot patients have a less effective stretch-shortening mechanism of the plantarflexor muscles. This could be due to different elastic properties of the muscle complex, inherent to their pathology [8]. Subsequently, there might be less stored energy that contributes to the ankle power generation. Additionally, the lower ankle moment might indicate that the force-generating capacity of clubfoot patients might be lower, resulting in a lower ankle power generation. This might have resulted in the lower hopping velocity that was seen in clubfoot patients. These results provide insight in the problems clubfoot patients have d","PeriodicalId":94018,"journal":{"name":"Gait & posture","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135299041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}