Sharif Digital Repository

Injuries of neuro-musculoskeletal system impose large costs to the modem societies. Studying the strategies of CNS in planning and control of movements can be helpful in developing diagnoSiS, prognosis and treatment procedures in clinical view and also in designing rehabilitation system and humanoid robots. Tow important features of human movements are redundancy problem and structured variability. Previous studies solved the redundancy problem mainly with optimization methods. Also optimal feedback control theory is the only method that successfully modeled structured variability in voluntary movements. Despite the appropriate outputs this methods are not based on physiological facts... 

The behavior movement of human is fundamentally concerned with the relationship between the central nervous system of motor control، and musculoskeletal system of a human. Optimal control was employed to relate these structures together. Movement is one of the important part of human life، CNS is important because it has the fundamental role in the movement. Investigators believe that CNS is learned by iteration movements from childhood and finally it chooses the movement that makes a cost function minimum value of itself. Researching for CNS modeling grows in recent years on the different part of human body. Because upper body have less difficulty in movements، it is more useful for CNS... 

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... 

Cerebral palsy (CP) is one the most prevalent neuromusculoskeletal disease amongst children. Damage in the central nervous system (CNS) causes defective growth of the musculoskeletal system during infancy to maturity, then leading to impairment of selective motor control (SMC), spasticity and sometimes contracture of musculotendinous junction. Treatment of Cerebral Palsy is limited to reduce complications. Medical procedures such as neurosurgery and orthopaedic surgeries or rehabilitation used as a common operation. Recently studies in the field of synergy directed a new path to understanding of human motor control complexity besides identification of functionality of musculoskeletal... 

Several diseases and injuries may cause disability in locomotion (especially walking). Spinal cord injuries, brain stroke and disease like Parkinson are the most major causes. In the past, some efforts has been made to reduce the effect of organ’s disabilities, but today, there is the chance of healing the spinal cord injury By using new (Schwann Cell) method. Due to long time stillness and severe muscles weakness; condensed physiotherapy exercise is essential to recover locomotion abilities, particularly in walking. In this way, if the practices matches with the normal walking (especially weight bearing); it has more physiological and psychological effect. In order to achieve this goal, a... 

Using biomechanical models is one of the most effective ways to analyze and assessment of spinal loads in occupational and daily activities. In spite of many advances in the spine modeling, personal factors especially body weight are ignored in most studies. Epidemiological studies show that high body weight is a very strong risk factor of low back pain (LBP) and disc degeneration. There are only few studies that evaluate the relationship between spinal loads and body weight. The goal of this study is analyzing the effect of body weight on spinal load. A detailed musculoskeletal model of lumbar spine with 18 degree of freedom and 76 muscles was developed. This model consists of two parts... 

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... 

Even though Patellofemoral pain syndrome is one of the most frequent pains and disabilities in knee area, the pathology of this illness has not achieved the needed accuracy and clearness. Most researchers believe the cause of this pain syndrome and disability of it, is abnormal activities of patella. Nevertheless, no non-invasive method has been presented to measure three-dimensional movements of patella in patients. It seems evolving a method based on tactile tracking which surface and touchable trait of knee bone is used can benefit to measure three-dimensional movements of patella non-invasively. On the basis of this, the main idea of the project is registering the pressure changes in... 

In cases with excessive anteversion even after adolescence, surgeons have to choose osteotomy surgery to modify this abnormality. This surgery and modifying the anatomical problem does not necessarily lead to modify the patients’ gait cycle abnormalities; the authors’ hypothesis is the probable reason may be the persistence of the implement of the patients’ kinematics compensation mechanism even after the surgery. This mechanism is used to almost correct the gait of those with excessive anteversion. First, by using gait analysis text books, a patient’s gait cycle is analyzed; this analysis is consist of 3DGA with EMG and observational gait. Then, by using OpenSim, the patient’s patterns of... 

Low back disorders (LBD) is one of the most musculo-skeletal disorders in industrial environments in which it can impose to the society.Therefore, it is very important to reaserch the causes of LBDs, prevention methods and evaluation risk factor in lifting tasks in order to avoid the prevalence of LBDs in society. There is no doubt heavy lifting has a significant role in emerging of LBDs. Hence, many safety risk assessment tools have been made by researchers.Using assessment tools, we need to know the input parameters corrospending to the assessment tools. Input parameters in assessment tools have been measured in a way of traditional method or by expensive equipment in laboratories. On... 

The recent project can be considered as a subset of Telerehabilitation, in the field of Telerehabilitation can be defined as the need for long-term data recording in order to determine each individual's movement pattern and compare it to the individual's best model or best practice. With this perspective, it can be said that the recent project, in more detail, remotely targets the use of foot plantar pressure to determine locomotor parameters. With this description, the FSR or force sensitive resistor sensor was selected for a number of reasons, including low cost, low weight and low thickness, and the data acquisition circuit was used to convert the sensors' analog signal to digital output,... 

Lifting is considered a major risk to people's health in life, particularly to the workers. Appropriate wearable tools for measuring the individual’s kinematic and kinetic movement are required for examining and analyzing the lifting activity to prevent injury in the workplace. Different wearable systems have been developed to calculate the force applied on the foot sole to analyze movement in various areas of gait analysis, occupational biomechanics, sports, and other areas. The accuracy and precision of these systems need to be tested before application in any of these areas. In this study, 3 subjects performed five different activities of symmetrical lifting by placing Pedar insoles in... 

Turan Toad-headed Agama is a lizard (Phrynocephalus mystaceus) inhabiting in the deserts of the Middle East. In order to hide from predators, it laterally vibrates (and slightly oscillates around the dorsal axis) to descend beneath the sand. Despite its low density, toad-headed agama easily burrows beneath the sand. The purpose of this study is to initially determine 3D kinematics of the agama's burial technique (frequency, amplitude and position of critical points of the body). After determining the motion, we will figure how the motion interacts with granular media and enables the animal to burry. This includes simulating animal's motion within granular media using discrete element method... 

Stroke is the main cause of disability in the world and the third cause of death, so spreading rehabilitation technique for post stoke patients is one of the most important targets un these days. The first prototype hand rehabilitation device was designed and fabricated in RCSTIM in 2008. Since the first prototype had been proved its effectiveness in clinical tests in the next phase industrial production of the device had to be considered at first all of the problems that had been observed during the clinical tests had to be solved for the future production. In the first series of experiments, clinical limitation and the interaction between the patient and the physiotherapist with the device... 

In this project, we use a novel mechanism to control the lumbar rotational profile and also the disc pressure of L3/L4 and L4/L5. Spine, as one of the most important parts of human musculoskeletal system, helps human beings to walk on two feet without much energy consumption. Any problem in this part may cause moving disorders or pain. To heal severe spine disorders, many different methods like surgery and implantation are adopted. To be sure of proper functionality in the human body, these methods should be tested clinically in advance. Cadaver spine testing in vitro, is accepted as a gold standard to evaluate new methods. One of the main challenges facing spine in vitro tests is how to... 

Realistic simulation of tool-tissue interactions can help developing more effective surgical training systems and simulators. In this study we used finite element and meshless modeling approaches to simulate the grasping procedure of a large intra-abdominal organ, i.e., kidney, during laparoscopic surgery. Results indicated that the accuracy of meshless method was comparable with that of the finite element, with the RMS errors in the range of 0.8 to 3.4 mm in different directions. The computational cost of the meshless method however, was much less than that of the finite element model. In order to verify the model, a silicon sample was used with the ship kidney geometry. For determination... 

Foot related problems or diseases such as plan foot pain, diabetic foot, arthritic foot, pathological flatfoot, ankle sprain, bone fracture or other sports related injuries have been costing a significant amount of medical expenditure. Abnormal loading patterns and high pressure on the foot as well as improper or ill-fitting footwear are thought to be one major mechanical cause of foot problems. Most ankle sprains respond favorably to nonsurgical treatment, such as those offered by physical therapists, doctors of chiropractic, and rehabilitation specialists. A comprehensive history and examination aid in diagnosing the severity and type of ankle sprain. Based on the diagnosis and an... 

In knee injuries that may not have the ability to improve and knee function is disturbed, usually total knee replacement surgery is performed. There are several ways in order to study the effect of different parameters and how the parameters affect the total knee disability, including removal from the patient body, laboratory studies and computer simulations. Study of damaged prosthesis from viewpoint of availability and laboratory ones from cost and duration of time encounter with problems, so the computer simulation have priority. In this project, a dynamic model of a total knee prosthesis during gait cycle has been developed with the help of finite element software. In this project,... 

Every year a significant number of people in the world suffer knee injuries due to sport activities and accidents. Ligament tearing accounts for majority of knee injury cases. Clinical tests for diagnosing ligament injuries, give us just qualitative results. Modern pieces of equipment quickly and precisely give us the status of ligaments. In this project, we attempt to design and manufacture a clinical equipment that could log ligament’s stiffness during the arthroscopy; such that this information could be screened throughout the test  

Low back pain is a widespread disorder in industrialized countries. Based on epidemiological reports, 80% of the population faces this activity limitation at least once in their lifetime which places tremendous human and economic costs to individuals and societies. Handling heavy loads, with fast trunk motions, repetitive movements, and awkward postures are some of the risk factors related to low back injuries. Hence, better understanding of the neuro-musculo-skeletal system performance would help us to recognize various abnormalities in spine behavior and assist us in a way to design the workplace to reduce the risk of injuries. For this purpose, we can use biomechanicals model to...