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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...
Role of Intra-Abdominal Pressure and Abdominal Muscle Activities on Spinal Stability and Spinal Loads
,
M.Sc. Thesis
Sharif University of Technology
;
ParnianPour, Mohamad
(Supervisor)
;
Firoozbakhsh, Keikhosrow
(Co-Advisor)
Abstract
Spine is one of the most important musculoskeletal systems of the human body. Any problem which is related to this part of human body causes pain and disability. Spinal compression forces are one of the main reasons of this disability and pain. It is assumed that intra-abdominal pressure causes spinal unloading in lifting. Studies usually don’t consider the role of intra-abdominal pressure and introduce it as an effective parameter which can increases spinal stability and influences spinal mechanics.Generation mechanism of intra-abdominal pressure remain enigmatic, studies that advocate the unloading effect of IAP usually consider a raise in IAP to be primarily due to the activity of...
Prediction of Surgical Procedures Effect on Mal-tracking Correction of Patello-femoral Joint Using Patient-specific Musculo-skeletal Modeling
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor) ; Zohoor, Hassan (Supervisor)
Abstract
According to the statistical studies, knee pain is the most common and costliest disorder after low back pain. One of its types is the patello-femoral disorder and instability. Patellar instability can be affected by different factors, such as: low depth of the trochlear groove, low height of the lateral femoral condyle, high length of the patellar tendon, abnormal lateral rotation of the tibia, unusual tibial attachment of the patellar tendon, small patellar size, general loosening of ligaments, etc. So, the mechanical properties of knee joint including patello-femoral joint, surrounding soft tissues, and incoming forces must be examined carefully, in order to find out suitable and...
Subject-Specific Musculoskeletal Modeling of Gait for a Patient with Torsional Misalignment of Lower Extremity
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor) ; Narimani, Roya (Supervisor)
Abstract
Torsional misalignment of lower extremities is a bone deformity of femur, tibia, knee twist or a complex of all these factors. These deformities affect the patient's gait kinematics. These patients are usually treated with osteotomy surgery with the aim of correction of anatomy. But it doesn't necessarily lead to the modification of gait. Therefor development and application of subject-specific musculoskeletal models to analyze patient's specific condition and predict corrective surgery results are considered. Accordingly, the aim of this project is to create a subject-specific musculoskeletal model for a patient with femoral anteversion in order to predict result of anatomical correction...
Design and Implementation of a Control Strategy to Sustain Postural Stability for a Lower Limb Exoskeleton
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Gholamreza (Supervisor) ; Moradi, Hamed (Supervisor)
Abstract
Nowadays, the developments in control and robotics provide rehabilitation and power augmentation applications for the exoskeleton robots. In the rehabilitation applications, the goal is to help elderly and persons with paraplegia to do their daily activities and movements. One of this applications is to help these individuals for postural stability and recovering balance after receiving perturbations. In this research, we propose a control strategy for a lower limb exoskeleton to help the wearer to recover balance after a perturbation without using crutches. Here, we concentrate on the stance phase when a push is exerted to the robot and try to make the system quite upright. Therefore, a...
Modeling of Renal Autoregulation Systems
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Firoozbakhsh, Keikhosrow (Supervisor)
Abstract
The mathematical analysis of the kidney has always been considered due to its complex performance. It’s about two decades that mathematicians work on the mathematical modeling of this tissue. Since Glomerular filtration of blood in the kidney has been regarded by physiologists for many years, they can access only to the qualitative data. Mathematicians can solve this problem by numerical modeling. In this research, an engineering model is presented for the analysis of this capillary network by investigating in the different scientific fields such as, physiology, medicine, computer science and mathematics. There are two major renal autoregulatory mechanisms, the myogenic response and the...
Control of Trunk Muscle Synergies to Maintain the Equilibrium and Stability of the Spine
, M.Sc. Thesis Sharif University of Technology ; Parnianpour, Mohammad (Supervisor) ; Asghari, Mohsen (Supervisor)
Abstract
Selection of muscle activation pattern to reach a specific goal by considering the complexities of neuromuscular system and the way it overcomes these complications, are of researchers’ space interest in motor control. One proposed solution for resolving these complexities is the concept of simple module (synergies) that suggests the combination of them leads to more complex activities. In the present work, the existence and arrangement of synergies in the lumbar spine have been studied. For this purpose, a model with 18- muscles at level of L4-L5 under utilized in the static condition. In order to obtain the muscular and stability synergies, a biomechanical model predicting muscle...
Modeling and Evaluation of a Large Laparoscopic Grasper With Flexible Fingers
, M.Sc. Thesis Sharif University of Technology ; Farahmand , Farzam (Supervisor) ; Kazemzadeh Hannani, Siamak (Co-Advisor)
Abstract
Laparoscopy is a minimally invasive surgical (MIS) procedure specific to the surgical sites within the abdomen. For this surgical method a laparoscope, a camera (endoscope), and a grasping instrument is needed. They all inserted in to the abdomen through openings (5 - 10 mm diameter side port). Currently used grasper heads are small and often with steel material. With respect to these two properties applying large forces that cause damage in the organs is inevitable. The aim of this project is to design a new large laparoscopic grasper head that applies pressure along the length of the lever arms and can take up tissues of large sizes. Based on surveys and estimations SMA, artificial muscles...
Simulation of Human Walking Using a Combination of Synergy and Central Pattern Generators Approaches
, Ph.D. Dissertation Sharif University of Technology ; Zohoor, Hassan (Supervisor) ; Farahmand, Farzam (Supervisor)
Abstract
Human walking as a rhythmic movement, despite of being simple in implementation, is so complex in biomechanical modeling and has attracted the attention of most of the researchers. Numerous theories and assumptions have been proposed for modeling this motor pattern. Central pattern generators are neural circuits in the spinal cord responsible for generating rhythmic motor patterns in rhythmic activities such as walking. On the other hand, muscle synergy has been introduced as a solution for alleviating the redundancy of the muscular system. In this hypothesis, the central nervous system activates muscle groups that are called muscle modules. Using this hypothesis facilitates the...
Effect of Iatrogenic Muscle Injuries on Spine Biomechanics During Posterior Lumbar Surgeries Using a Biomechanical Model for Design of Rehabilitation Exercises
, M.Sc. Thesis Sharif University of Technology ; Arjmand, Navid (Supervisor)
Abstract
Posterior lumbar surgery is often associated with extensive injuries to back muscles. In this thesis, the effect of such iatrogenic injuries in some patients was examined. For this purpose, the CSA of back muscles in 6 patients were measured using MR scan. To examine any natural change in CSAs of healthy people or instrument errors, same measurement were carried out on 10 healthy volunteers. In addition, a detailed anatomical model of an intact human spine was developed. With the aim of experimental studies and intact model, the post-operative model of patients was also developed. These two models were used to quantizing the change in activity of back muscles during some symmetric, normal...
Improvement and Manufacture of The Wearable Assistive Device to Support Spine in Static Holding Tasks
, M.Sc. Thesis Sharif University of Technology ; Parnianpour, Mohammad (Supervisor) ; Hoviattalab, Maryam (Supervisor)
Abstract
One of the most common diseases associated with musculo-skeletal ailment is low back pain which is epidemic among general public so that billions of dollars is spent annually to treat this disease. There are back pain prevention strategies include training on correct lifting, ergonomic tool design, and industrial automation amongst others. In recent years, assistive devices have also been used to prevent back pain. There are assistive devices that can be installed on the body and significantly have reduced forces required for Erector Spinae muscle and Lumbar moments. In this research, at first the anatomy of the spine and muscles and method of processing Electromyography (EMG) of muscles...
A Hyrid EMG-optimization Based Model of the Lumbar Spine to Estimate Muscle Forces in Different Tasks
, M.Sc. Thesis Sharif University of Technology ; Arjmand, Navid (Supervisor)
Abstract
Low back pains (LBP) are prevalent and costly. One of the important factors causing LBP is excessive axial compression and shear forces that are applied on the intervertebral discs during different activities. Due to lack of direct in vivo measurement methods for estimating these loads, musculoskeletal biomechanical models have been emerged as indispensable tools under various activities. Different biomechanical models have been suggested to estimate muscle forces and spinal loads base on optimization, EMG and hybrid (EMG assisted optimization, EMGAO) methods. Although there have been a number of studies on the differences between various optimization and EMG-based methods, there has been no...
Classification of Cerebral Palsy Patients based on Muscle Synergies
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor) ; Narimani, Roya (Supervisor)
Abstract
Cerebral palsy (CP) is one of the most common motor disability among children that caused by damage to brain or defective development of brain before, during or just after birth. Due to this damage, children with CP have cognitive and motor problems. As an important activity of daily living, walking enhances independence, social activities and quality of life. Much of therapy for children is aimed to improve their gait. A usual technique to evaluate how a person walk and detect abnormal features in walking pattern is gait analysis. Lots of studies have been done on gait kinematics of CPs and classified them based on their kinematis. The purpose of this thesis is studying muscles activity of...
Modeling of Human Quadriceps Muscles and Design of a Magnetorheological Fluid-based Muscle Strengthening Device
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor) ; Behzadi Poor, Saeed (Supervisor)
Abstract
The Quadriceps Muscle as one of the major muscles of the human body plays a key role in knee function. Strengthening of this muscle is recommanded to prevent knee pain and even cure some diseases. Many believe that by strengthening the medial part with respect to the lateral part of the quadriceps muscles, patellofemoral pain syndrome can be prevented or treated. In this regard, a muscle strengthening system, based on magneticorheological brake is designed which provides isometric, isotonic and isokinetic exercise of knee joint and also enables the selective muscle strengthening. Beforehand a musculoskeletal model of lower extremity is developed in OpenSim software, capable to estimate force...
EEG Noise Cancellation by Stochastic and Deterministic Approaches
, M.Sc. Thesis Sharif University of Technology ; Shamsollahi, Mohammad Bagher (Supervisor)
Abstract
Noise contamination is inevitable in biomedical recordings. In some cases biomedical recordings are highly contaminated with artifacts which make the effective recovering process hard to achieve. Many different methods have been proposed for artifact removal from biomedical signals but introducing an effective method which can present valuable data for medical analysis, is still an ongoing process.
This dissertation focuses on inter-ictal EEG denoising approaches including ICA-based and EMD-based methods and different combination of these methods. These methods are tested on simulated epileptic recordings which are contaminated with real muscle artifact and EEG signal. The denoised...
This dissertation focuses on inter-ictal EEG denoising approaches including ICA-based and EMD-based methods and different combination of these methods. These methods are tested on simulated epileptic recordings which are contaminated with real muscle artifact and EEG signal. The denoised...
Knee Joint Torque Estimation using EMG Signals for Sharif Exoskeleton Control Applications
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Gholamreza (Supervisor)
Abstract
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...
A Biomechanical Model for Evaluation of Shoulder Function: Detecting the
Relationship Between Muscles Activation Patterns and Shoulder Joint Torques Using Synergy Concept
,
M.Sc. Thesis
Sharif University of Technology
;
Parnianpour, Mohamad
(Supervisor)
;
Asghari, Mohsen
(Supervisor)
Abstract
The effects of combined task demands on the way muscles are recruited to balance external loads during posture and movement is of great importance in quantitative analysis of upper arm function. Pain and disability of shoulder joint is becoming more important as population spends more often interacting with computers in seated position and carrying repetitive tasks using upper extremities. Shoulder joint that is more dependent on the muscles for its normal function than other joints such as hip due to its small articular surface and large range motion has been used here to study its coordination during isometric exertions. Since, the numbers of tasks that could be performed are enormous. In...
Mechanical Design of an Anthropometric Lower Extremity Exoskeletal System
, M.Sc. Thesis Sharif University of Technology ; Meghdari, Ali (Supervisor)
Abstract
The main scope of this research is to develop an anthropometric lower extremity exoskeleal system in a virtual environment for augmentation purposes. The main challenge in the process of doing this research is to employ the biomechanical analysis of the human locomotion to provide the necessary background information for the design of devices that closely mimic the dynamics of the operator's motion. In this case, the appropriate degrees-of-freedom and associated range of motions for each joint should be determined. In addition, the kind of necessary actuators and measurement systems should be selected based on the muscle torque consumption analysis provided by a musculoskeletal model,...
A Musculoskeletal Model of the Hand and Forearm to Simulate the Rehabilitation Process of Stroke Survivors
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor) ; Saadat Foumani, Mahmoud (Supervisor) ; Forough, Bijan (Supervisor)
Abstract
Spasticity is a common phenomenon following stroke, which causes increase in muscle resistance to imposed movements. Most of the clinical measurements used by physiotherapists to evaluate spasticity are qualitative. Consequently, the reported results are subjective. The objective of this study was to develop a musculoskeletal model of the upper limb to simulate spasticity of muscles activating in wrist flexion-extension. Subjects in two groups of normal and stroke survivors participated in this study. Six normal subjects and three hemiplegia patients were exercised by the robotic instrument. Simultaneously, the resistive moment, the wrist joint position and the EMG of muscles were recorded....
Effect of Hand-Held Flexible-Bar on Postural Stability and Shoulder Muscle Synergies during Repetitive Planar Hand Exercises
, M.Sc. Thesis Sharif University of Technology ; Parnianpour, Mohammad (Supervisor) ; Hoviattalab, Maryam (Supervisor)
Abstract
Shoulder is one of the most important joints of the body with high degrees of freedom. Synergic analysis of the shoulder muscles shows the joint condition due to applied force or torque. The results of the linear COP parameters and nonlinear analysis indicate the characteristics of subjects postural stability. The flexi-bar is a rehabilitation tool which stimulates the muscles. In this study, the effect of bar on the body has been examined. The modeling is carried out in two horizontal and vertical condition of bar in sixteen separate positions in the upper right side quadrant of the model. Muscle activation and joint stiffness, force and torque were obtained. COP data in AP and ML were...