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Design and analysis of an original powered foot clearance creator mechanism for walking in patients with spinal cord injury
, Article Disability and Rehabilitation: Assistive Technology ; March , 2018 , Pages 1-5 ; 17483107 (ISSN) ; Badri, S ; Shayestehepour, H ; Arazpour, M ; Farahmand, F ; Mousavi, M. E ; Abdolahi, E ; Farkhondeh, H ; Head, J. S ; Golchin, N ; Mardani, M. A ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
Background: The aim of this study was to assess the performance of an original powered foot clearance creator (PFCC) mechanism worn in conjunction with an isocentric reciprocal gait orthosis (IRGO) and evaluate its effect on trunk compensatory movements and spatiotemporal parameters in nine healthy subjects. Method: A PFCC motorized mechanism was designed that incorporated twin sole plates, the movements of which enabled increased toe to floor clearance during swing phase. A prototype was constructed in combination with an IRGO, and hence was re-named as an IRGO-PFCC orthosis. The effects of IRGO-PFCC usage on the spatiotemporal parameters and trunk compensatory movements during walking were...
Evaluation of spinal internal loads and lumbar curvature under holding static load at different trunk and knee positions
, Article Pakistan Journal of Biological Sciences ; Volume 10, Issue 7 , 2007 , Pages 1036-1043 ; 10288880 (ISSN) ; Parnianpour, M ; Firoozabadi, S. M ; Kasemnejad, A ; Karimi, E ; Sharif University of Technology
Asian Network for Scientific Information
2007
Abstract
A study was performed to investigate how different trunk and knee positions while holding static loads affect the lumbar curvature and internal loads on the lumbar spine at L4-L5. Ten healthy male subjects participated in this study. Two inclinometers were used to evaluate the curvature of lumbar spine, lordosis, while a 3D static biomechanical model was used to predict the spinal compression and shear forces at L4-L 5. Eighteen static tasks while holding three level of load (0, 10 and 20 kg), two levels of knee position (45 and 180° of flexion) and three levels of trunk position (neutral, 15 and 30 degree of flexion) were simulated for 10 healthy male subjects. The results of this study...
A model-based approach for estimation of changes in lumbar segmental kinematics associated with alterations in trunk muscle forces
, Article Journal of Biomechanics ; 2017 ; 00219290 (ISSN) ; Arjmand, N ; Meakin, J. R ; Bazrgari, B ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
The kinematics information from imaging, if combined with optimization-based biomechanical models, may provide a unique platform for personalized assessment of trunk muscle forces (TMFs). Such a method, however, is feasible only if differences in lumbar spine kinematics due to differences in TMFs can be captured by the current imaging techniques. A finite element model of the spine within an optimization procedure was used to estimate segmental kinematics of lumbar spine associated with five different sets of TMFs. Each set of TMFs was associated with a hypothetical trunk neuromuscular strategy that optimized one aspect of lower back biomechanics. For each set of TMFs, the segmental...
Security and Configuration Improvement in TETRA Systems
, M.Sc. Thesis Sharif University of Technology ; Haj Sadeghi, Khosrow (Supervisor)
Abstract
TETRA (TErrestrial Trunked RAdio) is one of the mobile telecommunication standards which has improved in several aspects (voice, data, video, coverage, etc.), especially the security section during the last two decades. Although communication could be quite secure in TETRA when the encryption is used, however, attackers create new ways to bypass the encryption without the knowledge of the legitimate user. Security is performed in different levels and forms to create reliable operation and to protect information through the transmission path from interception and tampering. Since most of the TETRA users require the highest possible level of security, in this thesis we introduce a new...
Evaluation of Trunk Neuromuscular System Strategies through the Concept of Muscle Synergies
, M.Sc. Thesis Sharif University of Technology ; Parnianpour, Mohamad (Supervisor) ; Narimani, Roya (Supervisor) ; Mousavi, Javad (Supervisor)
Abstract
Low Back Pain (LBP) is an important public health problem and also a source of continuing economic concern in across the world. Many clinicians and researchers have focused on LBP due to the prevalence of it, especially in industrialized societies in recent years. Despite technological advances in diagnosis and the introduction of numerous interventions, besides increasing automation in the workplaces, the incidence of back pain in a wide range of workers in industrial environments has been reported. A better understanding of the different functions of the neuromuscular system of the spine may lead to adopt strategies to prevent LBP incidence as well as provide appropriate exercises...
The effect of chronic low back pain on trunk accuracy in a multidirectional isometric tracking task
, Article Spine ; Vol. 39, Issue. 26 , 2014 , pp. E1608-E1615 ; ISSN: 1362-2436 ; Mousavi, S. J ; Sedaghatnejad, E ; Talebian, S ; Parnianpour, M ; Sharif University of Technology
Abstract
Study Design. A cross-sectional study to quantify trunk motor control during multidirectional isometric tracking tasks.Objective. To investigate the effect of chronic low back pain (LBP) on trunk neuromuscular performance while participants performed isometric exertions of trunk muscles to track targets in different angles with various magnitudes.Summary of Background Data. Tracking tasks especially in multidirectional activities are among the common research methods to quantify human motor control in different conditions. However, little information is available on trunk motor control during these tasks. There is no study investigating trunk accuracy during multidirectional isometric...
Can simple trunk muscle models balance and stabilize lumbar spine during support of symmetric and asymmetric loads? a FE model study
, Article 2007 ASME Summer Bioengineering Conference, SBC 2007, Keystone, CO, 20 June 2007 through 24 June 2007 ; 2007 , Pages 443-444 ; 0791847985 (ISBN); 9780791847985 (ISBN) ; Shirazi Adl, A ; Parnianpour, M ; Sharif University of Technology
2007
Sex-Dependent estimation of spinal loads during static manual material handling activities—combined in vivo and in silico analyses
, Article Frontiers in Bioengineering and Biotechnology ; Volume 9 , 2021 ; 22964185 (ISSN) ; Arjmand, N ; Pan, F ; Zander, T ; Schmidt, H ; Sharif University of Technology
Frontiers Media S.A
2021
Abstract
Manual material handling (MMH) is considered as one of the main contributors to low back pain. While males traditionally perform MMH tasks, recently the number of females who undertake these physically-demanding activities is also increasing. To evaluate the risk of mechanical injuries, the majority of previous studies have estimated spinal forces using different modeling approaches that mostly focus on male individuals. Notable sex-dependent differences have, however, been reported in torso muscle strength and anatomy, segmental mass distribution, as well as lifting strategy during MMH. Therefore, this study aimed to use sex-specific models to estimate lumbar spinal and muscle forces during...
Controllability and maintenance of human trunk response surface for isometric extension strength
, Article ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, ESDA2010, 12 July 2010 through 14 July 2010 ; Volume 1 , July , 2010 , Pages 733-738 ; 9780791849156 (ISBN) ; Farahmand, F ; Meghdari, A ; Hakkak, F ; Parnianpour, M ; ASME Turkey Section; Loughborough University ; Sharif University of Technology
2010
Abstract
From an ergonomic point of view, quantitative assessment of the feasibility of the task performance is an intricate process, which combines the multidimensional task demand profile with the individual's multidimensional performance capacity profile. Trunk muscle strength is affected by the trunk posture but it is not clear how the variability of trunk muscle is affected by the trunk posture or exertion level. A validated triaxial dynamometer, Sharif-LIST, was used for to model the surface response of trunk muscle extension strength variability as a function of trunk posture in the sagittal, coronal and transverse planes in standing position. Fifteen healthy males with no history of low back...
A model-based approach for estimation of changes in lumbar segmental kinematics associated with alterations in trunk muscle forces
, Article Journal of Biomechanics ; Volume 70 , March , 2018 , Pages 82-87 ; 00219290 (ISSN) ; Arjmand, N ; Meakin, J ; Bazrgari, B ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The kinematics information from imaging, if combined with optimization-based biomechanical models, may provide a unique platform for personalized assessment of trunk muscle forces (TMFs). Such a method, however, is feasible only if differences in lumbar spine kinematics due to differences in TMFs can be captured by the current imaging techniques. A finite element model of the spine within an optimization procedure was used to estimate segmental kinematics of lumbar spine associated with five different sets of TMFs. Each set of TMFs was associated with a hypothetical trunk neuromuscular strategy that optimized one aspect of lower back biomechanics. For each set of TMFs, the segmental...
Design and Manufacturing a Wearable Measuring System for Trunk Movements
, M.Sc. Thesis Sharif University of Technology ; Parnianpour, Mohamad (Supervisor) ; Narimani, Roya (Supervisor) ; Moshiri, Behzad (Co-Advisor) ; Hoviattalab, Maryam (Co-Advisor)
Abstract
Measurement of human movement during work, sport as daily activities has important effects for rehabilitation and biomechanics experts.
Recently, several researches are concentrated on this technology significantly because of new progress in sensors and fusion sensors. In the near future, wearable and ambulatory devices will be used considerably in biomedical applications. In this study, we reviewed some methods about wearable measuring system then introduced and designed innovative wearable clothing for this purpose. Some specifications and advantages of our system in comparison with relevant researches are; using textile sensors that are manufactured through nano electro active polymer...
Recently, several researches are concentrated on this technology significantly because of new progress in sensors and fusion sensors. In the near future, wearable and ambulatory devices will be used considerably in biomedical applications. In this study, we reviewed some methods about wearable measuring system then introduced and designed innovative wearable clothing for this purpose. Some specifications and advantages of our system in comparison with relevant researches are; using textile sensors that are manufactured through nano electro active polymer...
Nonlinear Analysis of Dynamic Spine Stability in Healthy and Low Back Pain Patients During Repetitive Flexion Extension Tasks
, M.Sc. Thesis Sharif University of Technology ; Arjmand, Navid (Supervisor)
Abstract
Objective: Stability is important to prevent falls during occupational and daily living activities. Control parameters such as speed, direction of motion and external load can affect stability pattern. The purpose of this study was to evaluate the effect of the mentioned control parameters on stability control pattern.
Methods: Kinematic data (rotation angles) to 19 healthy volunteers and 19 patients with low back pain associated with repeated trunk bending motion in eight different conditions of speed (high and slow), direction (symmetric and asymmetric planes) and external load (with and without load), was evaluated. Since the volunteers do during dynamic movements, they must also be...
Methods: Kinematic data (rotation angles) to 19 healthy volunteers and 19 patients with low back pain associated with repeated trunk bending motion in eight different conditions of speed (high and slow), direction (symmetric and asymmetric planes) and external load (with and without load), was evaluated. Since the volunteers do during dynamic movements, they must also be...
Performance evaluation and enhancement of random access procedure in TETRA networks
, Article 2010 6th Conference on Wireless Advanced, WiAD 2010, 27 June 2010 through 29 June 2010 ; June , 2010 ; 9781424470716 (ISBN) ; Ghorashi, S. A ; Khodaian, A. M ; Sharif University of Technology
2010
Abstract
In this paper, random access procedure in terrestrial trunked radio (TETRA) networks is described and modeled. Then, the impact of different random access parameters on performance metrics such as "delay" and "throughput" is evaluated. Moreover, in order to have a fast "call setup" which is one of the most important features of TETRA, it is shown that random access delay can be minimized, while maintaining peak throughput. by adaptively adjusting the random access parameters according to the backlogged traffic. The performance improvement of the proposed adaptive parameter adjustment is proved via extensive simulation results
Trunk biomechanical models based on equilibrium at a single-level violate equilibrium at other levels
, Article European Spine Journal ; Volume 16, Issue 5 , 2007 , Pages 701-709 ; 09406719 (ISSN) ; Shirazi Adl, A ; Parnianpour, M ; Sharif University of Technology
2007
Abstract
Accurate estimation of muscle forces in various occupational tasks is critical for a reliable evaluation of spinal loads and subsequent assessment of risk of injury and management of back disorders. The majority of biomechanical models of multi-segmental spine estimate muscle forces and spinal loads based on the balance of net moments at a single level with no consideration for the equilibrium at remaining levels. This work aimed to quantify the extent of equilibrium violation and alterations in estimations when such models are performed at different levels. Results are compared with those of kinematics-driven model that satisfies equilibrium at all levels and EMG data. Regardless of the...
Dynamic iso-resistive trunk extension simulation: Contributions of the intrinsic and reflexive mechanisms to spinal stability
, Article Technology and Health Care ; Volume 15, Issue 6 , 2007 , Pages 415-431 ; 09287329 (ISSN) ; Shirazi Adl, A ; Hemami, H ; Mousavi, S. J ; Parnianpour, M ; Sharif University of Technology
IOS Press
2007
Abstract
The effects of external resistance on the recruitment of trunk muscles and the role of intrinsic and reflexive mechanisms to ensure the spinal stability are significant issues in spinal biomechanics. A computational model of spine under the control of 48 anatomically oriented muscle actions was used to simulate iso-resistive trunk movements. Neural excitation of muscles was attained based on inverse dynamics approach along with the stability-based optimization. The effect of muscle spindle reflex response on the trunk movement stability was evaluated upon the application of a perturbation moment. In this study, the trunk extension movement at various resistance levels while extending from...
Lumbopelvic muscle activation patterns in three stances under graded loading conditions: Proposing a tensegrity model for load transfer through the sacroiliac joints
, Article Journal of Bodywork and Movement Therapies ; Vol. 18, Issue. 4 , October , 2014 , pp. 633-642 ; ISSN: 13608592 ; Maroufi, N ; Sanjari, M. A ; Parnianpour, M ; Levin, S. M ; Sharif University of Technology
Abstract
Purpose: According to the conventional arch model of the pelvis, stability of the sacroiliac joints may require a predominance of form and force closure mechanisms: the greater the vertical shear force at the sacroiliac joints, the greater the reliance on self-bracing by horizontally or obliquely oriented muscles (such as the internal oblique). But what happens to the arch model when a person stands on one leg? In such cases, the pelvis no longer has imposts, leaving both the arch, and the arch model theory, without support. Do lumbopelvic muscle activation patterns in one-legged stances under load suggest compatibility with a different model? This study compares lumbopelvic muscle...
Trunk muscles strength and endurance in chronic low back pain patients with and without clinical instability
, Article Journal of Back and Musculoskeletal Rehabilitation ; Volume 25, Issue 2 , 2012 , Pages 123-129 ; 10538127 (ISSN) ; Maroufi, N ; Ebrahimi, I ; Farahmand, F ; Parnianpour, M ; Sharif University of Technology
2012
Abstract
Objectives: Previous research has shown inconsistent findings regarding muscle endurance in chronic low back pain (CLBP). Questions also remain about muscle endurance in patients with clinical instability. The aim of this study was to investigate trunk muscles strength and endurance in CLBP patients with and without clinical instability. Methods: 32 CLBP patients (15 with and 17 without clinical instability) and 39 matched healthy subjects participated in this study. The standing extension test was performed to assess the strength and endurance of the lumbar extensors while recording their electromyographic activity. The patients' disability was evaluated using the Oswestry and Roland-Morris...
Subject-specific biomechanics of trunk: musculoskeletal scaling, internal loads and intradiscal pressure estimation
, Article Biomechanics and Modeling in Mechanobiology ; Volume 15, Issue 6 , 2016 , Pages 1699-1712 ; 16177959 (ISSN) ; Shirazi Adl, A ; Arjmand, N ; El Ouaaid, Z ; Plamondon, A ; Sharif University of Technology
Springer Verlag
Abstract
Development of a subject-specific computational musculoskeletal trunk model (accounting for age, sex, body weight and body height), estimation of muscle forces and internal loads as well as subsequent validation by comparison with measured intradiscal pressure in various lifting tasks are novel, important and challenging. The objective of the present study is twofold. First, it aims to update and personalize the passive and active structures in an existing musculoskeletal kinematics-driven finite element model. The scaling scheme used an existing imaging database and biomechanical principles to adjust muscle geometries/cross-sectional-areas and passive joint geometry/properties in accordance...
Capability and recruitment patterns of trunk during isometric uniaxial and biaxial upright exertion
, Article Clinical Biomechanics ; Volume 23, Issue 5 , 2008 , Pages 527-535 ; 02680033 (ISSN) ; Parnianpour, M ; Nordin, M ; Sharif University of Technology
2008
Abstract
Background: Work-related risk factors of low back disorders have been identified to be external moments, awkward postures, and asymmetrical dynamic lifting amongst others. The distinct role of asymmetry of load versus posture is hard to discern from the literature. Hence, the aim of this study is to measure isometric trunk exertions at upright standing posture at different exertion level and degree of asymmetry to further delineate the effects of exertion level and asymmetry on neuromuscular capability response. Methods: Fifteen healthy volunteers randomly performed trunk exertions at three levels (30%, 60%, and 100% of maximum voluntary exertion and five different angles (0°, 45°, 90°,...
Sagittal range of motion of the thoracic spine using inertial tracking device and effect of measurement errors on model predictions
, Article Journal of Biomechanics ; Volume 49, Issue 6 , 2016 , Pages 913-918 ; 00219290 (ISSN) ; Arjmand, N ; Sharif University of Technology
Elsevier Ltd
Abstract
Range of motion (ROM) of the thoracic spine has implications in patient discrimination for diagnostic purposes and in biomechanical models for predictions of spinal loads. Few previous studies have reported quite different thoracic ROMs. Total (T1-T12), lower (T5-T12) and upper (T1-T5) thoracic, lumbar (T12-S1), pelvis, and entire trunk (T1) ROMs were measured using an inertial tracking device as asymptomatic subjects flexed forward from their neutral upright position to full forward flexion. Correlations between body height and the ROMs were conducted. An effect of measurement errors of the trunk flexion (T1) on the model-predicted spinal loads was investigated. Mean of peak voluntary total...