Search for: knee-joint
0.008 seconds
Total 25 records

    Effects of medial thrust gait on lower extremity kinetics in patients with knee osteoarthritis

    , Article Ortopedia, traumatologia, rehabilitacja ; Volume 23, Issue 2 , 2021 , Pages 115-120 ; 20844336 (ISSN) Bokaeian, H. R ; Esfandiarpour, F ; Zahednejad, S ; Kouhzad Mohammadi, H ; Farahmand, F ; Sharif University of Technology
    NLM (Medline)  2021
    BACKGROUND: Medial thrust (MT) gait is a nonsurgical approach for reducing the knee adduction moment (KAM) in patients with knee osteoarthritis. However, its usefulness is indeterminate due to scarcity of research about changes in lower extremity kinetics and the ground reaction force (GRF) which have been investigated in this study. MATERIALS AND METHODS: Twenty patients (6 males, 14 females, age: 56.2±6.2 years) with medial knee osteo-arthritis participated in this cross-sectional study. A 12-camera motion analysis system and two force plates recorded kinematic and GRF data while participants walked barefoot along a 12m path with 1) their regular gait pattern and 2) MT gait pattern. The... 

    Lower extremity kinematic coupling during single and double leg landing and gait in female junior athletes with dynamic knee valgus

    , Article BMC Sports Science, Medicine and Rehabilitation ; Volume 13, Issue 1 , 2021 ; 20521847 (ISSN) Dadfar, M ; Sheikhhoseini, R ; Jafarian, M ; Esmaeili, A ; Sharif University of Technology
    BioMed Central Ltd  2021
    Background: Dynamic knee valgus (DKV) is a common lower extremity movement disorder among females. This study aimed to investigate kinematic couplings between lower extremity joints in female junior athletes with DKV during single and double-leg landing and gait. Methods: Twenty-six physically active female junior athletes (10–14 years old) with DKV were recruited. Kinematic couplings between rearfoot, tibia, knee, and hip were extracted using eight Vicon motion capture cameras and two force plates. Zero-lag cross-correlation coefficient and vector coding were used to calculate kinematic couplings between joints during physical tasks. Paired t-test and Wilcoxon tests were run to find... 

    Feasibility of a powered knee joint in providing stance and swing phase knee flexion when using a knee-ankle-foot orthosis

    , Article Journal of Prosthetics and Orthotics ; Volume 29, Issue 4 , 2017 , Pages 177-182 ; 10408800 (ISSN) Rafiaei, M ; Arazpour, M ; Bahramizadeh, M ; Farahmand, F ; Jamshidi, N ; Samadian, M ; Sharif University of Technology
    Background The aim of this study was to develop a new stance control knee-ankle-foot orthosis (SCKAFO) and determine its efficacy on specific spatiotemporal and kinematic parameters. Method Seven healthy volunteer subjects participated in this study. After orthotic gait training, subjects participated in a four-part data collection session that consisted of gait evaluation with normal walking, SCKAFO with locked knee joint, SCKAFO without initial flexion (IF) mode, and SCKAFO with IF mode. Results Walking with any of the control knee-ankle-foot orthoses (KAFOs) produced a significant reduction in walking speed compared with normal walking. There was no significant difference in walking speed... 

    Computer Simulation of Arthrometric Diagnosis of Partial ACL-Injured Knee

    , M.Sc. Thesis Sharif University of Technology Rahemi, Hadi (Author) ; Farahmand, Farzam (Supervisor) ; Parnianpour, Mohammad (Supervisor)
    Knee pain and injuries are very common in athletes. Anterior cruciate ligament (ACL) injury is one of the most important reason of knee acute and chronic pains. As ACL plays a significant role in knee stability and due to amount of reported ACL related injuries, much effort has been placed on finding proper and on time diagnosis and treatment of these injuries. Arthrometric methods are the most non-invasive reliable diagnosis option; however they are not fully capable of separating partial injuries from intact joint. This weakness can be investigated by quantifying the tests using computer simulations; so far few studies have been conducted toward this goal. In this study a two dimensional... 

    Development of a Combined 2D-3D Image Registration Method for Dynamic Measurement of Knee Joint Tracking

    , M.Sc. Thesis Sharif University of Technology Sobhanieh, Niloufar (Author) ; Farahmand, Farzam (Supervisor)
    2D-3D image registration has been adopted in many clinical applications such as kinematic analysis of bones in knee and ankle joints. Because it is not possible to take dynamic images in 3D and 2D dynamic images such as fluoroscopic images lack spatial information. For comparing two images it’s necessary to make their dimensions the same. So in this research we prepared a code in MATLAB to generate digitally Reconstructed Radiograph (DRR) from the CT image in different positions and then be compared with 2D fluoroscopic image. Registering two images could be done either with comparing their intensities or their mutual features. We combined these two methods and developed a cost function with... 

    Design for Fabrication of a Knee Prosthesis Wear Simulator

    , M.Sc. Thesis Sharif University of Technology Tahsili Seghale, Alireza (Author) ; Durali, Mohammad (Supervisor)
    Total knee replacement surgery is the most common joint replacement in the world. Considering the increasing rate of this procedure and costs and difficulties of the repeated operation, many efforts have been made to improve the performance and lifetime of implants. The Polyethylene component of the implant is the most prone component to fail due to wear. To evaluate new knee prosthesis designs, it is necessary to have a wear test simulator. Objective of this project is to detail design a knee prosthesis wear simulator according to ISO 14243 in order to investigate the performance of prosthesises in long term and under in-vivo conditions. During this project, studies have been made to get... 

    Knee Joint Torque Estimation using EMG Signals for Sharif Exoskeleton Control Applications

    , M.Sc. Thesis Sharif University of Technology Ghiasi Noughaby, Amir (Author) ; Vossoughi, Gholamreza (Supervisor)
    The human body has more than 600 muscles that cause movement. Disability and motor disorders are some of the problems that people may face due to some factors such as accident, spinal cord injuries, disorders and brain damage, and the presence of a problem in neurological commands due to stroke. One of the proposed methods for solving the problems of people with motor disorder is the use of exoskeletons to generate stimulus. Exoskeletones are electromechanical devices designed to assist human movement, and patients are used to correct their movements using specific motor patterns. Exoskeletones can also be used as an auxiliary device for carrying heavy loads. Many studies have been conducted... 

    Dynamic Modeling and Simulation of Knee Joint Using an Artificial Neural Network Model

    , M.Sc. Thesis Sharif University of Technology Amouzandeh, Reza (Author) ; Sayadi, Hassan (Supervisor)
    One of the important challenges in gait analysis is to know the consequences and extent of the impact of an injury or failure and the outcome of any intervention. The purpose of this study was to identify and categorize three gait patterns of a healthy person, an individual with ruptured anterior cruciate ligament, and an individual with surgically reconstructed anterior cruciate ligament using knee joint kinematic information in normal walking. To do this, data from the knee joint curve during the gait cycle in sagittal, frontal and transverse planes were used as a neural network input. Four neural networks were designed to detect and isolate the three gait patterns from each other. The... 

    Design and Manufacturing of Gradient Cellular Tibial Stem for Total Knee Replacement

    , M.Sc. Thesis Sharif University of Technology Taheri, Atiyeh (Author) ; Farahmand, Farzam (Supervisor) ; Bahrami Nasab, Marjan (Co-Supervisor)
    Loosening of uncemented tibial component is one the most common causes of total knee prosthesis failure which is a result of short-term factors such as instability and incomplete osseointegration as well as long-term factors such as peri-prosthetic stress shielding and bone atrophy. Porous cellular structures for tibial stem have been considered as a solution to this problem. This project is aimed to achieve an optimal gradient porous cellular design of tibial stem that in addition to sufficient mechanical strength, provides a perfect osseointegration and prevents bone resorption by incorporating appropriate porosity size, small micro-motion and favorable stress distribution on bone. A... 

    Do the soft tissues located outside tibiofemoral joint have a role in bearing the compressive loads of the joint? An in-vitro study on sheep stifle joints

    , Article Gazzetta Medica Italiana Archivio per le Scienze Mediche ; Volume 172, Issue 7-8 , 2013 , Pages 595-601 ; 03933660 (ISSN) Hakkak, F ; Rostami, M ; Parnianpour, M ; Jabalameli, M ; Sharif University of Technology
    Aim. The compressive loads on the tibiofemoral joint are normally assumed to be borne solely via contact and pressing of the cartilage surfaces of tibia and femur. However, recent findings suggest that non-contact load-bearing mechanisms are active in the joint as well. In this context, a non-contact load-bearing mechanism involving soft tissue connections outside the tibiofemoral joint has been hypothesized as well. This paper addresses the validity of this hypothesis and the possible involvement of several soft tissue connections outside the joint. Methods. Sheep stifle (knee) joints were studied in vitro. The specimens were loaded in fixed displacement. Various soft tissues outside the... 

    Stiffness of knee-spanning external fixation systems for traumatic knee dislocations: A biomechanical study

    , Article Journal of Orthopaedic Trauma ; Volume 24, Issue 11 , Nov , 2010 , Pages 693-696 ; 08905339 (ISSN) Mercer, D ; Firoozbakhsh, K ; Prevost, M ; Mulkey, P ; Decoster, T. A ; Schenck, R ; Sharif University of Technology
    Objective: The purpose of this study was to compare the relative stiffness of four common external fixation (XF) configurations used to span and stabilize the knee after knee dislocation. Methods: Synthetic composite femora and tibiae connected with cords were used to simulate a knee. Four configurations of external fixation were tested: anterior femoral pins with monotube (XF1), anterolateral femoral pins with monotube (XF2), anterolateral femoral pins with two connecting rods (XF3), and hinged ring fixator (XF4). Six specimens of each configuration were loaded nondestructively in varus/valgus, anterior-to- posterior shear, flexion/extension, axial compression, internal/external torsion,... 

    Dynamic performance of different knee mechanisms with compliant joints

    , Article Scientia Iranica ; Volume 23, Issue 3 , 2016 , Pages 1055-1063 ; 10263098 (ISSN) Ghaemi, N ; Zohoor, H ; Ghaemi, H ; Sharif University of Technology
    Sharif University of Technology  2016
    Loss of lower extremities has been one of the main problems in human life. Although most of the available knee devices are aesthetically acceptable, there is a necessity for lighter and more compact mechanisms, especially for younger amputees. This problem can be solved by the combining compliant mechanism design with traditional mechanism design methods. In this study, one group of the prosthetics that is known as the compliant knee mechanisms" is evaluated. At first, the different knee mechanisms, such as fourand six-bar knee linkages are investigated to calculate the values of the control moments (actuator torque). Then, the suitable location (where the actuator torque is to be exerted)... 

    Markerless human motion tracking using microsoft kinect SDK and inverse kinematics

    , Article 12th Asian Control Conference, ASCC 2019, 9 June 2019 through 12 June 2019 ; 2019 , Pages 504-509 ; 9784888983006 (ISBN) Bilesan, A ; Behzadipour, S ; Tsujita, T ; Komizunai, S ; Konno, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Motion capture systems are used to gauge the kinematic features of the motion in numerous fields of research. Despite superb accuracy performance, the commercial systems are costly and difficult to use. To solve these issues, Kinect has been proposed as a low-priced markerless motion capture sensor, and its accuracy has been assessed using previous motion capture systems. However, in many of these studies, the anatomical joint angles captured using the Kinect are compared to the 3D rotation angles reported by the gold standard motion capture systems. These incompatibilities in the determination of the human joint angles can lead to higher error estimation. To accomplish a valid accuracy... 

    The effect of load carrying on the human lower extremity muscle activation during walking

    , Article 5th International Symposium on Mechatronics and its Applications, ISMA 2008, Amman, 27 May 2008 through 29 May 2008 ; October , 2008 ; 9781424420346 (ISBN) Selk Ghafari, A ; Meghdari, A ; Vossoughi, G. R ; Sharif University of Technology
    This paper focuses on the biomechanical aspects of human load carrying in order to provide a physiological framework for designing the more anthropometric assistive systems. An 8degrees-of-freedom musculoskeletal model with twenty functional muscle groups in the lower extremity was developed to simulate the movement in sagittal plane. Inverse dynamics based optimization approach was employed to estimate the excitation level of the muscles. Activation patterns of the muscles illustrate the importance role of the soleus in supporting of the body during load carrying. Also power distribution analysis of the muscles reveals that the plantar flexors of the ankle, extensors of the knee and hip... 

    Rehabilitation after ACL injury: A fluoroscopic study on the effects of type of exercise on the knee sagittal plane arthrokinematics

    , Article BioMed Research International ; Volume 2013 , July , 2013 ; 23146133 (ISSN) Norouzi, S ; Esfandiarpour, F ; Shakourirad, A ; Salehi, R ; Akbar, M ; Farahmand, F ; Sharif University of Technology
    A safe rehabilitation exercise for anterior cruciate ligament (ACL) injuries needs to be compatible with the normal knee arthrokinematics to avoid abnormal loading on the joint structures. The objective of this study was to measure the amount of the anterior tibial translation (ATT) of the ACL-deficient knees during selective open and closed kinetic chain exercises. The intact and injured knees of fourteen male subjects with unilateral ACL injury were imaged using uniplanar fluoroscopy, while the subjects performed forward lunge and unloaded/loaded open kinetic knee extension exercises. The ATTs were measured from fluoroscopic images, as the distance between the tibial and femoral reference... 

    The gait and energy efficiency of stance control knee-ankle-foot orthoses: A literature review

    , Article Prosthetics and Orthotics International ; Volume 40, Issue 2 , 2016 , Pages 202-214 ; 03093646 (ISSN) Rafiaei, M ; Bahramizadeh, M ; Arazpour, M ; Samadian, M ; Hutchins, S. W ; Farahmand, F ; Mardani, M. A ; Sharif University of Technology
    SAGE Publications Inc  2016
    Background: The use of knee-ankle-foot orthoses with drop locked knee joints produces some limitations for walking in subjects with quadriceps muscle weakness. The development of stance control orthoses can potentially improve their functionality. Objectives: The aim of this review was to compare the evidence of the effect of stance control orthoses to knee-ankle-foot orthoses with drop locked knee joints in improving kinematic variables and energy efficiency of walking by subjects with quadriceps muscle weakness caused by different pathologies. Study design: Literature review. Methods: Based on selected keywords and their composition, a search was performed in Google Scholar, PubMed,... 

    Design, construction, and evaluation of “sensor lock”: an electromechanical stance control knee joint

    , Article Disability and Rehabilitation: Assistive Technology ; Volume 13, Issue 3 , 2018 , Pages 226-233 ; 17483107 (ISSN) Arazpour, M ; Ahmadi Bani, M ; Baniasad, M ; Samadian, M ; Golchin, N ; Sharif University of Technology
    Taylor and Francis Ltd  2018
    Background and aim: Most currently-available stance control knee ankle foot orthoses (SCKAFOs) still need full knee extension to lock the knee joint, and they are still noisy, bulky, and heavy. Therefore, the aim of this study was to design, construct, and evaluate an original electromechanical SCKAFO knee joint that could feasibly solve these problems, and thus address the problems of current stance control knee joints with regards to their structure, function, cosmesis, and cost. Method: Ten able-bodied (AB) participants and two (knee ankle foot orthosis) KAFO users were recruited to participate in the study. A custom SCKAFO with the same set of components was constructed for each... 

    Computer simulation of knee arthrometry to study the effects of partial ACL injury and tibiofemoral contact

    , Article 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS'08, Vancouver, BC, 20 August 2008 through 25 August 2008 ; 2008 , Pages 895-898 ; 9781424418152 (ISBN) Rahemi, H ; Farahmand, F ; Rezaeian, T ; Parnianpour, M ; Sharif University of Technology
    IEEE Computer Society  2008
    We simulated the knee arthrometry test to obtain a deeper understanding of the joint's stability behavior and interpret the arthrometric results more effectively. A 2D sagittal plane finite element model of the lower limb in the standard configuration of knee arthrometry was developed using ANSYS APDL. A detailed model of the knee joint was considered including the femoral articulating contour represented by an ellipse, the tibial plateau represented by a circular arc, and four major knee ligaments and their individual bundles represented by linear and nonlinear tensile springs. A deformable layer of articular cartilage was also considered over the tibial plateau to simulate the bones... 

    A rigid body spring model to investigate the lateral shift-Restraining force behavior of the patellar

    , Article 29th Annual International Conference of IEEE-EMBS, Engineering in Medicine and Biology Society, EMBC'07, Lyon, 23 August 2007 through 26 August 2007 ; 2007 , Pages 4679-4682 ; 05891019 (ISSN) ; 1424407885 (ISBN); 9781424407880 (ISBN) Jafari, A ; Farahmand, F ; Meghdari, A ; Sharif University of Technology
    Patellar lateral stability was studied using a 2D transverse plane model with deformable articular surfaces. Quadriceps muscles and patellar tendon were considered as strings with predefined forces and lateral and medial retinaculum as tensile springs. Deformation behavior of articular cartilage was modeled by a set of compression springs perpendicular to articular surfaces, based on rigid body spring model method (RBSM). Patellar lateral stability was investigated using restraining force method (the external force required to cause up to 10 mm lateral displacement on patella). The results were in good agreement with experimental reports for normal joint, vastus lateralis and vastus medialis... 

    Trunk, pelvis, and knee kinematics during running in females with and without patellofemoral pain

    , Article Gait and Posture ; Volume 89 , 2021 , Pages 80-85 ; 09666362 (ISSN) Haghighat, F ; Ebrahimi, S ; Rezaie, M ; Shafiee, E ; Shokouhyan, S. M ; Motealleh, A ; Parnianpour, M ; Sharif University of Technology
    Elsevier B.V  2021
    Background: Females are two times more likely to develop patellofemoral pain (PFP) than males. Abnormal trunk and pelvis kinematics are thought to contribute to the pathomechanics of this condition. However, there is a scarcity of evidence investigating proximal segments kinematics in females with PFP. Research question: The purpose of this study was to investigate whether females with PFP demonstrate altered trunk, pelvis, and knee joint kinematics compared with healthy controls during running. Methods: Thirty-four females (17 PFP, 17 controls) underwent a 3-dimensional motion analysis during treadmill running at preferred and fixed speeds, each trial for 30 s. Variables of interest...