Loading...
Search for:
low-back-disorders
0.011 seconds
A computation tool to simulate trunk motion and predict muscle activation by assigning different weights to physical and physiological criteria
, Article Journal of Medical Imaging and Health Informatics ; Volume 1, Issue 3 , 2011 , Pages 231-237 ; 21567018 (ISSN) ; Sedighi, A ; Salarieh, H ; Asghari, M ; Parnianpour, M ; Sharif University of Technology
Abstract
A central problem in motor control is to understand how the many biomechanical degrees of freedom are coordinated to achieve a goal. A common assumption is that Central Nervous System (CNS) will plan tasks based on open-loop optimal control theory which simultaneously predicts state variables and motor commands based on a compound objective function. A 3D computational method incorporated with 18 anatomically oriented muscles is used to simulate human trunk system. Direct collocation method allows us to convert a constrained optimal control problem to a common nonlinear programming problem to assume the spinal stability condition. Trunk movement from the upright standing to 60 degrees of...
Comparison of trunk muscle forces, spinal loads and stability estimated by one stability- and three EMG-assisted optimization approaches
, Article Medical Engineering and Physics ; Volume 37, Issue 8 , 2015 , Pages 792-800 ; 13504533 (ISSN) ; Arjmand, N ; Shirazi-Adl, A ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Various hybrid EMG-assisted optimization (EMGAO) approaches are commonly used to estimate muscle forces and joint loads of human musculoskeletal systems. Use of EMG data and optimization enables the EMGAO models to account for inter- and intra-individual variations in muscle recruitments while satisfying equilibrium requirements. Due to implications in ergonomics/prevention and rehabilitation/treatment managements of low-back disorders, there is a need to evaluate existing approaches. The present study aimed to compare predictions of three different EMGAO and one stability-based optimization (OPT) approaches for trunk muscle forces, spinal loads, and stability. Identical measured...
Trunk biomechanics during maximum isometric axial torque exertions in upright standing
, Article Clinical Biomechanics ; Volume 23, Issue 8 , 2008 , Pages 969-978 ; 02680033 (ISSN) ; Shirazi Adl, A ; Parnianpour, M ; Sharif University of Technology
2008
Abstract
Background: Activities involving axial trunk rotations/moments are common and are considered as risk factors for low back disorders. Previous biomechanical models have failed to accurately estimate the trunk maximal axial torque exertion. Moreover, the trunk stability under maximal torque exertions has not been investigated. Methods: A nonlinear thoracolumbar finite element model along with the Kinematics-driven approach is used to study biomechanics of maximal axial torque generation during upright standing posture. Detailed anatomy of trunk muscles with six distinct fascicles for each abdominal oblique muscle on each side is considered. While simulating an in vivo study of maximal axial...