scholarly journals Relationships between movements of the lower limb joints and the pelvis in open and closed kinematic chains during a gait cycle

2016 ◽  
Vol 51 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Zdenek Svoboda ◽  
Miroslav Janura ◽  
Patrik Kutilek ◽  
Eva Janurova
Keyword(s):  
Lower Limb ◽  
Gait Cycle ◽  
External Rotation ◽  
Body Height ◽  
Movement Pattern ◽  
Kinematic Chain ◽  
Lower Limbs ◽  
Initial Contact ◽  
3D Analysis ◽  
Kinematic Chains

AbstractLots of athletic skills performed during practice or competition are initiated by the legs, where athletes either walk or run prior to executing specific skills. Kinematic chains are used to describe the relationships between body segments and joints during movement. The aim of this study was to determine the relationships between movements of lower limb segments and the pelvis in open and closed kinematic chains while walking. The experimental group consisted of 32 males (age 23.3 ± 2.5 years, body mass 78.1 ± 8.7 kg, body height 182 ± 6 cm). For 3D analysis, an optoelectronic system Vicon MX (7 cameras, frequency 200 Hz) was used. Positioning of the segments was determined by the PlugInGait Model. Each participant executed five trials at speeds ranging from 1.38 to 1.52 m·s-1. The relationships between angle variables of the lower limbs and the pelvis in selected gait cycle phases were evaluated using STATISTICA software (version 10.0) and the Spearman correlation. The highest numbers of moderate and large correlations were found at opposite toe off, heel rise and initial contact for the sagittal and transversal planes in comparison to the frontal plane. The closed kinematic chain had a stronger impact on determining the movement pattern. The instructions or interventions focusing on closed kinematic chain alternation are more effective for changes in a movement pattern. The preferred limb initiates kinematics in the direction of propulsion, while the non-preferred limb in internal and external rotation.

Design of a Human Knee Reeducation Mechanism

2019 ◽  
Vol 11 (1) ◽  
pp. 42-53
Author(s):  
Allaoua Brahmia ◽  
Ridha Kelaiaia
Keyword(s):  
Lower Limb ◽  
Mechanical Design ◽  
Kinematic Chain ◽  
Lower Limbs ◽  
Kinematic Structure ◽  
Robotic Device ◽  
Human Knee ◽  
Kinematic Study ◽  
Rehabilitation Exercise ◽  
New Machine

Abstract To establish an exercise in open muscular chain rehabilitation (OMC), it is necessary to choose the type of kinematic chain of the mechanical / biomechanical system that constitutes the lower limbs in interaction with the robotic device. Indeed, it’s accepted in biomechanics that a rehabilitation exercise in OMC of the lower limb is performed with a fixed hip and a free foot. Based on these findings, a kinematic structure of a new machine, named Reeduc-Knee, is proposed, and a mechanical design is carried out. The contribution of this work is not limited to the mechanical design of the Reeduc-Knee system. Indeed, to define the minimum parameterizing defining the configuration of the device relative to an absolute reference, a geometric and kinematic study is presented.

scholarly journals Effects of Different Forms of Extrinsic Feedback on the Accuracy of Force Production and to Differentiate this Force in the Simple Cyclic Movements of the Upper and Lower Limb

2020 ◽  
Vol 72 (3) ◽  
pp. 39-56
Author(s):  
Stefan Szczepan ◽  
Zofia Wróblewska ◽  
Andrzej Klarowicz ◽  
Ryszard Błacha ◽  
Marek Rejman
Keyword(s):  
Lower Limb ◽  
Retention Test ◽  
Repeated Measures ◽  
Body Height ◽  
Force Production ◽  
Lower Limbs ◽  
Verbal Feedback ◽  
Physically Active ◽  
Cyclic Movements ◽  
Extrinsic Feedback

Abstract Background: This study aimed to assess the accuracy of force production by the limbs and to identify the ability to differentiate this force during a progressively increasing value, in response to different types of extrinsic feedback. Material and methods: The study involved nineteen healthy and physically active boys and girls aged 12.82±0.34 years, body height 157.05±9.02 cm, and body mass 44.89±7.89 kg. The tasks were to perform a series of right and left upper limb pulls and pushes with increasing force using the levers of the kinesthesiometer and a series of lower limb presses on the pedal of the kinesthesiometer. The tasks were completed in three feedback conditions: no feedback, sound feedback, verbal feedback, and the retention test was used. To assess the level of accuracy of force production, the novel index of force production accuracy (FPAIndex) was used. Results: The outcomes expressing the value of FPAIndex on the point scale indicated that the highest level of kinesthetic differentiation was observed when no feedback was provided (1.17 points), and the lowest kinesthetic differentiation was recorded when verbal feedback was provided (3.33 points). However, they were devoid of statistical value. The repeated-measures analysis of variance ANOVA with the Tukey post-hoc test (HSD) indicated a significant lowest (p=0.0402) level of accuracy of FPA (x̄ 36.12±18.29 [N]) only for the act of left lower limb press (LL PRESS) in the retention test, while no feedback was provided to the subjects. Conclusions: The results of this study showed that verbal and sound extrinsic feedback did not affect the accuracy of force production by the upper and lower limbs and the ability to differentiate this force in simple movements among children.

scholarly journals Dysfunctional muscle activities and co-contraction in the lower-limb of lumbar disc herniation patients during walking

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Wei Wang ◽  
Hui Wei ◽  
Runxiu Shi ◽  
Leitong Lin ◽  
Lechi Zhang ◽  
...  
Keyword(s):  
Lumbar Disc Herniation ◽  
Disc Herniation ◽  
Lower Limb ◽  
Gait Cycle ◽  
Lumbar Disc ◽  
Lower Limbs ◽  
Heel Strike ◽  
Control Group ◽  
Double Support ◽  
Support Phase

AbstractThis study aimed to investigate lower-limb muscle activities in gait phases and co-contraction of one gait cycle in patients with lumbar disc herniation (LDH). This study enrolled 17 LDH patients and 17 sex- and age-matched healthy individuals. Bilateral muscle activities of the rectus femoris (RF), biceps femoris long head (BL), tibialis anterior (TA), and lateral gastrocnemius (LG) during walking were recorded. The gait cycle was divided into four phases by the heel strike and top off according to the kinematics tracks. Root mean square (RMS), mean frequency (MF), and co-contraction of surface electromyography signals were calculated. The LDH patients showed enhanced BL RMS during the single support phase (SS), second double support phase, and swing phase (SW) as well as decreased MF of RF during SS and of TA and LG during SW (p < 0.05). The co-contraction of the TA-LG was increased in LDH patients than in the control group (p < 0.05). Positive correlations were observed between TA-LG co-contraction (affected side, r = 0.557, p = 0.020; contralateral side, r = 0.627, p = 0.007) and the Oswestry disability index scores in LDH patients. LDH patients have increased BL firing rate and insufficient motor unit recruitment in specific phases in the lower limbs during walking. Dysfunction in LDH patients was associated with immoderate intermuscular co-contraction of the TA-LG during walking.

scholarly journals Design and Simulation Analysis of a Robot-Assisted Gait Trainer with the PBWS System

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Jiancheng (Charles) Ji ◽  
Yufeng Wang ◽  
Guoqing Zhang ◽  
Yuanyuan Lin ◽  
Guoxiang Wang
Keyword(s):  
Lower Limb ◽  
Degrees Of Freedom ◽  
Gait Cycle ◽  
Simulation Analysis ◽  
The Elderly ◽  
Lower Limbs ◽  
Robot Assisted ◽  
Limb Rehabilitation ◽  
Gait Trainer ◽  
Lower Limb Rehabilitation

In response to the ever-increasing demand of lower limb rehabilitation, this paper presents a novel robot-assisted gait trainer (RGT) to assist the elderly and the pediatric patients with neurological impairments in the lower limb rehabilitation training (LLRT). The RGT provides three active degrees of freedom (DoF) to both legs that are used to implement the gait cycle in such a way that the natural gait is not significantly affected. The robot consists of (i) the partial body weight support (PBWS) system to assist patients in sit-to-stand transfer via the precision linear rail system and (ii) the bipedal end-effector (BE) to control the motions of lower limbs via two mechanical arms. The robot stands out for multiple modes of training and optimized functional design to improve the quality of life for those patients. To analyze the performance of the RGT, the kinematic and static models are established in this paper. After that, the reachable workspace and motion trajectory are analyzed to cover the motion requirements and implement natural gait cycle. The preliminary results demonstrate the usability of the robot.

A Technique to Detect Fatigue in the Lower Limbs

2014 ◽  
Author(s):  
Abdullatif A. Alwasel ◽  
Eihab M. Abdel-Rahman ◽  
Carl T. Haas
Keyword(s):  
Phase Space ◽  
Knee Joint ◽  
Lower Limb ◽  
Time History ◽  
Warning System ◽  
Kinematic Chain ◽  
Kinematic Parameter ◽  
Lower Limbs ◽  
Body Parts ◽  
Reconstructed Phase Space

As muscles fatigue, their passive and active mechanical properties change increasing the susceptibility of the human body to damage. The state-of-the-art technique for muscle fatigue detection, EMG signals, is cumbersome. This paper presents a technique to detect fatigue by tracking a kinematic parameter of the musculoskeletal system. The method uses the time-history of a single joint angle to detect fatigue in the lower limbs. A sensor is mounted to the knee joint to measure the knee flexion angle. Time delay embedding is used to track the orbit of knee joint motions in a reconstructed phase-space. The reconstructed phase-space allows us to obtain information about other body parts and joints of the lower limb in addition to the knee joint, since they are all connected in an open kinematic chain. Long-time drift in the orbit location and shape in phase-space is quantified and used as a measure of lower limb fatigue. The proposed technique presents a mobile, wireless, and cheap method to assess fatigue that can act as an early warning system for the lower limb.

Effect of Different Placement of Heel Rockers on Lower-Limb Joint Biomechanics in Healthy Individuals

2018 ◽  
Vol 108 (3) ◽  
pp. 231-235 ◽  
Author(s):  
Maedeh Farzadi ◽  
Zahra Safaeepour ◽  
Hoda Nabavi ◽  
Masumeh Bagherzadeh Cham ◽  
Mohammad Ebrahim Mousavi
Keyword(s):  
Range Of Motion ◽  
Lower Limb ◽  
Lower Limbs ◽  
Medial Malleolus ◽  
Initial Contact ◽  
Healthy Individuals ◽  
Peak Knee ◽  
Joint Biomechanics ◽  
Single Limb Support ◽  
Rocker Shoes

Background: Rocker shoes are commonly prescribed to healthy and pathologic populations to decrease stress on the lower limbs. An optimal rocker shoe design must consider both toe and heel rockers. Heel rockers are as effective as toe rockers in relieving foot plantar pressures. However, most studies have focused on the position of toe rockers. The aim of this study was to assess the effect of different heel rocker apex placements on lower-limb kinetics and kinematics. Methods: Eighteen healthy females participated in this study. Three pairs of rocker shoes with rocker apex positions anterior to the medial malleolus (shoe A), at the medial malleolus (shoe B), and posterior to the medial malleolus (shoe C) were fabricated and then compared with a flat shoe (shoe D). Kinetic and kinematic data were collected, and lower-extremity joint ranges of motion and moments were calculated. Results: Ankle range of motion was increased by shoe C (P = .04) during initial contact and by shoe A (P = .02) during single-limb support. Peak knee moment was significantly larger for shoes A and B (P &lt; .05) during single-limb support. Conclusions: Results showed that forward and backward shifting of the heel rocker apex could change the knee moment and ankle joint range of motion in the stance phase of gait. Therefore, placement of the heel rocker in a rocker-bottom shoe can be manipulated to promote the desired lower-limb motion, at least in healthy individuals.

Development of a Lower Limb Orthosis to Form Neuromuscular Patterning

2014 ◽  
Author(s):  
Karla A. Camarillo–Gómez ◽  
Gerardo I. Pérez-Soto ◽  
Luis A. Torres-Rico
Keyword(s):  
Quality Of Life ◽  
Control System ◽  
Lower Limb ◽  
Gait Cycle ◽  
Lower Cost ◽  
Sagittal Plane ◽  
Lower Limbs ◽  
Human Gait

In this paper, a lower limb orthosis is proposed to form the human gait neuromuscular patterns in patients with myelomeningocele. The orthosis has two lower limbs of 2–DOF each which reduces the motion of the hip and knee to the sagittal plane. The orthosis are assembled in a back support which also supports the patients weight. The control system for the orthosis allows to reproduce in a repetitive, controlled and autonomous way the human gait cycle at different velocities according to the patient requirements; so that, the neuromuscular patterning can be supervised by a therapist. The development of these orthosis seeks to improve the quality of life of those infants with myelomenigocele and to introduce a lower cost Mexican technology with Mexican anthropometric dimensions.

KINEMATIC DIFFERENCES IN LUMBOPELVIC AND HIP MOVEMENT PATTERNS DURING A LOWER LIMB MOVEMENT TEST BETWEEN TWO GROUPS OF PEOPLE WITH LOW BACK PAIN

2017 ◽  
Vol 17 (02) ◽  
pp. 1750030 ◽  
Author(s):  
MEISSAM SADEGHISANI ◽  
MOHAMMAD JAFAR SHATERZADEH ◽  
MOHAMMAD TAGHI KARIMI ◽  
FRANCIS FATOYE ◽  
MARJAN AKBARI ◽  
...  
Keyword(s):  
Low Back Pain ◽  
Lower Limb ◽  
External Rotation ◽  
Movement Pattern ◽  
Low Back ◽  
Pelvic Rotation ◽  
Rotation Test ◽  
Lower Limb Movement ◽  
Hip Rotation ◽  
Movement Test

Increased lumbopelvic motion during limb movements’ tests was reported in low back pain (LBP) patients with and without rotational demand activities. The aim of this study was to compare lumbopelvic movement pattern between two groups of LBP patients with and without rotational demand activity during active hip external rotation test. A total of 39 patients with non-specific chronic LBP participated in this study. Patients were allocated into two groups, in first group 15 subjects (mean [Formula: see text] years) with rotational demand activities such as tennis, squash and golf, and in second group 24 subjects (mean [Formula: see text]) without rotational demand activities participated in current study. Kinematic data from lumbopelvic-hip region during active hip external rotation test (AHER) were collected by a 3D motion analysis system. Variables including range of motion (ROM) of hip external rotation, pelvic rotation, pelvic rotation during first half of hip rotation motion and timing of pelvic-hip movement were calculated by MATLAB software for both sides and after this, independent t-test was used to compare the variables between two groups of study. The mean lumbopelvic rotation in lower extremities tests for both sides and lumbopelvic rotation in the dominant limb external rotation test in the patients with rotational demand activities were significantly more than other group ([Formula: see text]). During dominant lower limb movement test, pelvic rotation in first half of movement and in patients with rotational activities was greater than in non-rotational group but hip rotation was statistically lesser than other group ([Formula: see text]). Other variables between the two groups were not significantly different ([Formula: see text]). The result of the study suggest that LBP patients who have rotational demand sports activities may move their lumbopelvic region in a greater magnitude during the AHER test than LBP people without rotational demand activities. Therefore, Lumbopelvic movement pattern in different groups of patients with LBP and based on their specific activities is different with each other.

Analysis of the activation modalities of the lower limb muscles during walking

2020 ◽  
Vol 28 (5) ◽  
pp. 521-532 ◽  
Author(s):  
Wei Li ◽  
Zhongli Li ◽  
Shuyan Qie ◽  
Huaqing Yang ◽  
Xuemei Chen ◽  
...  
Keyword(s):  
Lower Limb ◽  
Muscle Activation ◽  
Gait Cycle ◽  
Lower Limbs ◽  
Medial Gastrocnemius ◽  
Peak Time ◽  
Lower Limb Muscles ◽  
Emg Signal ◽  
Limb Muscles ◽  
Activation Intervals

BACKGROUND: Walking is a basic human activity and many orthopedic diseases can manifest with gait abnormalities. However, the muscle activation intervals of lower limbs are not clear. OBJECTIVE: The aim of this study was to explore the contraction patterns of lower limb muscles by analyzing activation intervals using surface electromyography (SEMG) during walking. METHODS: Four muscles including the tibialis anterior (TA), lateral gastrocnemius (LG), medial gastrocnemius (MG), and rectus femoris (RF) of bilateral lower extremity of 92 healthy subjects were selected for SEMG measurements. The number of activations (activation intervals) and the point of the highest root mean square (RMS) EMG signal in the percentage of the gait cycle (GC) were used to analyze muscle activities. RESULTS: The majority of TA and RF showed two activation intervals and both gastrocnemius parts three activation intervals during walking. The point of the highest RMS EMG signal in the percentage of the GC for TA, LG, MG and RF are 5%, 41%, 40%, and 8%, respectively. The activation intervals were mostly affected by age, height, different genders and bilateral limbs. CONCLUSION: This study identified the different activation intervals (four for each muscle) and the proportion of healthy adults in which they occurred during the normal gait cycle. These different activation intervals provided a new insight to evaluate the function of nerves and muscles. In addition, the activation interval and RMS peak time proposed in this study can be used as new parameters for gait analysis.

scholarly journals Biomechanical study on the stress distribution of the knee joint after residual rotation deformity of tibial fracture

2020 ◽  
Author(s):  
Ming Li ◽  
Yanbin Zhu ◽  
Ning Wei ◽  
Wenli Chang ◽  
Zeyue Jin ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Knee Joint ◽  
Lower Limb ◽  
External Rotation ◽  
Biomechanical Study ◽  
Lower Limbs ◽  
Neutral Position ◽  
Lateral Stress ◽  
Significant Difference ◽  
The Difference

Abstract Objectives To investigate the effect of residual rotation deformity on the stress distribution of the knee joint after surgery to treat middle and upper tibial fractures. Methods Fourteen adult cadaver specimens that were preserved with formalin were included, and the tibias were randomly positioned at 0 degree, 5 degrees, 10 degrees, and 15 degrees from the line of force of the lower limb. These positions modeled deformities of 5 degrees, 10 degrees, and 15 degrees from the line of force. Low-pressure pressure-sensitive film technology measured the stress distribution of the knee joint under different degrees of rotation deformity. Results Under a vertical load of 400 N, the difference between the medial and lateral stress of the knee joint was significantly different between the different tibia deformities (P<0.05), and the medial stress of the knee joint was higher than the lateral stress. The current study showed that there were statistically significant differences in the medial stress on the knee joint at all angles (including the neutral position of 0 degrees) (F=89.753, P<0.001) . There was a statistically significant difference in the lateral stresses of the knee joint between different rotation deformities (including the neutral position of 0 degrees) (F=102.998, P<0.001). Conclusions Residual rotation deformity after fracture of middle and upper tibia can lead to poor alignment of lower limb force and change of articular contact characteristics of knee joint, especially external rotation of tibia.Therefore, orthopedic surgeons should correct the malalignment of lower limbs to the greatest extent and reduce the rotation deformity as far as possible.

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