Matching Items (28)
Description
Muscular weakness is a common manifestation for Stroke survivors and for patients with Anterior Cruciate Ligament reconstruction leading to reduced functional independence, especially mobility. Several rigid orthotic devices are being designed to assist mobility. However, limitations in majority of these devices are: 1) that they are constrained only to level walking applications, 2) are mostly bulky and rigid lacking user comfort. For these reasons, rehabilitation using soft-robotics can serve as a powerful modality in gait assistance and potentially accelerate functional recovery. The characteristics of soft robotic exosuit is that it’s more flexible, delivers high power to weight ratio, and conforms with the user’s body structure making it a suitable choice. This work explores the implementation of an existing soft robotic exosuit in assisting knee joint mechanism during stair ascent for patients with muscular weakness. The exosuit assists by compensating the lack of joint moment and minimizing the load on the affected limb. It consists of two I-cross-section soft pneumatic actuators encased within a sleeve along with insole sensor shoes and control electronics. The exosuit actuators were mechanically characterized at different angles, in accordance to knee flexion in stair gait, to enable the generation of the desired joint moments. A linear relation between the actuator stiffness and internal pressure as a function of the knee angle was obtained. Results from this characterization along with the insole sensor outputs were used to provide assistance to the knee joint. Analysis of stair gait with and without the exosuit ‘active’ was performed, using surface electromyography (sEMG) sensors, for two healthy participants at a slow walking speed. Preliminary user testing with the exosuit presented a promising 16% reduction in average muscular activity of Vastus Lateralis muscle and a 3.6% reduction on Gluteus Maximus muscle during the stance phase and unrestrained motion during the swing phase of ascent thereby demonstrating the applicability of the soft-inflatable exosuit in rehabilitation.
ContributorsMuthukrishnan, Niveditha (Author) / Polygerinos, Panagiotis (Thesis advisor) / Lockhart, Thurmon (Committee member) / Peterson, Daniel (Committee member) / Arizona State University (Publisher)
Created2018
Description
Individuals fluent in sign language who have at least one deaf parent are considered native signers while those with non-signing, hearing parents are non-native signers. Musculoskeletal pain from repetitive motion is more common from non-natives than natives. The goal of this study was twofold: 1) to examine differences in upper extremity (UE) biomechanical measures between natives and non-natives and 2) upon creating a composite measure of injury-risk unique to signers, to compare differences in scores between natives and non-natives. Non-natives were hypothesized to have less favorable biomechanical measures and composite injury-risk scores compared to natives. Dynamometry was used for measurement of strength, electromyography for ‘micro’ rest breaks and muscle tension, optical motion capture for ballistic signing, non-neutral joint angle and work envelope, a numeric pain rating scale for pain, and the modified Strain Index (SI) as a composite measure of injury-risk. There were no differences in UE strength (all p≥0.22). Natives had more rest (natives 76.38%; non-natives 26.86%; p=0.002) and less muscle tension (natives 11.53%; non-natives 48.60%; p=0.008) for non-dominant upper trapezius across the first minute of the trial. For ballistic signing, no differences were found in resultant linear segment acceleration when producing the sign for ‘again’ (natives 27.59m/s2; non-natives 21.91m/s2; p=0.20). For non-neutral joint angle, natives had more wrist flexion-extension motion when producing the sign for ‘principal’ (natives 54.93°; non-natives 46.23°; p=0.04). Work envelope demonstrated the greatest significance when determining injury-risk. Natives had a marginally greater work envelope along the z-axis (inferior-superior) across the first minute of the trial (natives 35.80cm; non-natives 30.84cm; p=0.051). Natives (30%) presented with a lower pain prevalence than non-natives (40%); however, there was no significant difference in the modified SI scores (natives 4.70 points; non-natives 3.06 points; p=0.144) and no association between presence of pain with the modified SI score (r=0.087; p=0.680). This work offers a comprehensive analysis of all the previously identified UE biomechanics unique to signers and helped to inform a composite measure of injury-risk. Use of the modified SI demonstrates promise, although its lack of association with pain does confirm that injury-risk encompasses other variables in addition to a signer’s biomechanics.
ContributorsRoman, Gretchen Anne (Author) / Swan, Pamela (Thesis advisor) / Vidt, Meghan (Committee member) / Peterson, Daniel (Committee member) / Lockhart, Thurmon (Committee member) / Ofori, Edward (Committee member) / Arizona State University (Publisher)
Created2018
Description
Injuries and death associated with fall incidences pose a significant burden to society, both in terms of human suffering and economic losses. The main aim of this dissertation is to study approaches that can reduce the risk of falls. One major subset of falls is falls due to neurodegenerative disorders such as Parkinson’s disease (PD). Freezing of gait (FOG) is a major cause of falls in this population. Therefore, a new FOG detection method using wavelet transform technique employing optimal sampling window size, update time, and sensor placements for identification of FOG events is created and validated in this dissertation. Another approach to reduce the risk of falls in PD patients is to correctly diagnose PD motor subtypes. PD can be further divided into two subtypes based on clinical features: tremor dominant (TD), and postural instability and gait difficulty (PIGD). PIGD subtype can place PD patients at a higher risk for falls compared to TD patients and, they have worse postural control in comparison to TD patients. Accordingly, correctly diagnosing subtypes can help caregivers to initiate early amenable interventions to reduce the risk of falls in PIGD patients. As such, a method using the standing center-of-pressure time series data has been developed to identify PD motor subtypes in this dissertation. Finally, an intervention method to improve dynamic stability was tested and validated. Unexpected perturbation-based training (PBT) is an intervention method which has shown promising results in regard to improving balance and reducing falls. Although PBT has shown promising results, the efficacy of such interventions is not well understood and evaluated. In other words, there is paucity of data revealing the effects of PBT on improving dynamic stability of walking and flexible gait adaptability. Therefore, the effects
of three types of perturbation methods on improving dynamics stability was assessed. Treadmill delivered translational perturbations training improved dynamic stability, and adaptability of locomotor system in resisting perturbations while walking.
of three types of perturbation methods on improving dynamics stability was assessed. Treadmill delivered translational perturbations training improved dynamic stability, and adaptability of locomotor system in resisting perturbations while walking.
ContributorsRezvanian, Saba (Author) / Lockhart, Thurmon (Thesis advisor) / Buneo, Christopher (Committee member) / Lieberman, Abraham (Committee member) / Abbas, James (Committee member) / Deep, Aman (Committee member) / Arizona State University (Publisher)
Created2019
Description
This study investigated the effect of a small added load on postural stability in older adults. Sixteen healthy older adults (6 male, 10 female, age=72 ± 3.2y, height=172± 9.3 cm, weight=84± 7.6 kg) performed clinical measures of postural control with different loads placed on the shoulders (0%, 1% and 3% bodyweight). The functional reach test, comprising a forward, right and left lateral reach, along with COP data measured through the use of a force plate were the postural control measures utilized in this study. COP data used were COP sway velocity and COP mean sway area, in the form of a 95% confidence ellipse. During the COP trials, visual input (eyes open and eyes closed) and surface conditions (firm and foam) were varied to evaluate the effect of the loads under different conditions. Two trials of each measurement were performed for all tests, and participants were allowed rest intervals as needed. Anticipated results show a decreased reach distance of 8% in the forward direction, and a 7% decrease in the left and right lateral directions under a 1% bodyweight load. For expected results of COP velocity, there will be a 12% increase from baseline COP sway velocity in the 1% bodyweight condition. Anticipated results for COP sway area show a 39% increase in the eyes open firm surface, under a 1% bodyweight load, and a 40% increase under the 3% load. These expected results show a significant effect on postural control with a 1% and 3% bodyweight load placed on the shoulders of older adults. This information may be valuable in combatting the epidemic of falls seen among the elderly population, as part of an exercise program for improving balance and postural stability.
ContributorsScherwinski, Eric (Author) / Dounskaia, Natalia (Thesis director) / Vidt, Meghan (Committee member) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Introduction: Individuals with rotator cuff tears have been found to compensate in their movement patterns by using lower thoracohumeral elevation angles during certain tasks, as well as increased internal rotation of the shoulder (Vidt et al., 2016). Leading joint hypothesis suggests there is one leading joint that creates the foundation for the entire limb motion, and there are other subordinate joints which monitor the passive interaction torque and create a net torque aiding to limb motions required for the task. This experiment seeks to establish a better understanding of joint control strategies during a wide range of arm movements. Based on the leading joint hypothesis, we hypothesize that when a subject has a rotator cuff tear, their performance of planar and three-dimensional motions should be altered not only at the shoulder, which is often the leading joint, but also at other joints on the arm, such as the elbow and wrist. This paper will focus on the effect of normal aging on the control of the joints of the arm.
Methods: There were 4 groups of participants: healthy younger adults (n=14)(21.74 ± 1.97), healthy older adults (n=12)(55-75), older adults (n=4)(55-75) with a partial-thickness rotator cuff tear, and older adults (n=4)(55-75) with a full-thickness rotator cuff tear (RCT). All four groups completed strength testing, horizontal drawing and pointing tasks, and three dimensional (3D) activities of daily living. Kinematic and kinetic variables of the arm were obtained during horizontal and 3D tasks using data from 12 reflective markers placed on the arm, 8 motion capture cameras, and Cortex motion capture software (Motion Analysis Corp., Santa Rosa, CA). Strength testing tasks were measured using a dynamometer. All strength testing and 3D tasks were completed for three trials and horizontal tasks were completed for two trials.
Results: Results of the younger adult participants showed that during the forward portion of seven 3D tasks, there were four phases of different joint control mechanics seen in a majority of the movements. These phases included active rotation of both the shoulder and the elbow joint, active rotation of the shoulder with passive rotation of the elbow, passive rotation of the shoulder with active rotation of the elbow, and passive rotation of both the shoulder and the elbow. Passive rotation during movements was a result of gravitational torque on the different segments of the arm and interaction torque caused as a result of the multi-joint structure of human limbs. The number of tested participants for the minor RCT, and RCT older adults groups is not yet high enough to produce significant results and because of this their results are not reported in this article. Between the older adult control group and the young adult control group in the tasks upward reach to eye height and hair comb there were significant differences found between the groups. The differences were found in shorter overall time and distance between the two groups in the upward eye task.
Discussion: Through the available results, multiple phases were found where one or both of the joints of the arm moved passively which further supports the LJH and extends it to include 3D movements. With available data, it can be concluded that healthy older adults use movement control strategies, such as shortening distance covered, decreasing time percentage in active joint phases, and increasing time percentage in passive joint phases, to account for atrophy along with other age-related declines in performance, such as a decrease in range of motion. This article is a part of a bigger project which aims to better understand how older adults with RCTs compensate for the decreased strength, the decreased range of motion, and the pain that accompany this type of injury. It is anticipated that the results of this experiment will lead to more research toward better understanding how to treat patients with RCTs.
Methods: There were 4 groups of participants: healthy younger adults (n=14)(21.74 ± 1.97), healthy older adults (n=12)(55-75), older adults (n=4)(55-75) with a partial-thickness rotator cuff tear, and older adults (n=4)(55-75) with a full-thickness rotator cuff tear (RCT). All four groups completed strength testing, horizontal drawing and pointing tasks, and three dimensional (3D) activities of daily living. Kinematic and kinetic variables of the arm were obtained during horizontal and 3D tasks using data from 12 reflective markers placed on the arm, 8 motion capture cameras, and Cortex motion capture software (Motion Analysis Corp., Santa Rosa, CA). Strength testing tasks were measured using a dynamometer. All strength testing and 3D tasks were completed for three trials and horizontal tasks were completed for two trials.
Results: Results of the younger adult participants showed that during the forward portion of seven 3D tasks, there were four phases of different joint control mechanics seen in a majority of the movements. These phases included active rotation of both the shoulder and the elbow joint, active rotation of the shoulder with passive rotation of the elbow, passive rotation of the shoulder with active rotation of the elbow, and passive rotation of both the shoulder and the elbow. Passive rotation during movements was a result of gravitational torque on the different segments of the arm and interaction torque caused as a result of the multi-joint structure of human limbs. The number of tested participants for the minor RCT, and RCT older adults groups is not yet high enough to produce significant results and because of this their results are not reported in this article. Between the older adult control group and the young adult control group in the tasks upward reach to eye height and hair comb there were significant differences found between the groups. The differences were found in shorter overall time and distance between the two groups in the upward eye task.
Discussion: Through the available results, multiple phases were found where one or both of the joints of the arm moved passively which further supports the LJH and extends it to include 3D movements. With available data, it can be concluded that healthy older adults use movement control strategies, such as shortening distance covered, decreasing time percentage in active joint phases, and increasing time percentage in passive joint phases, to account for atrophy along with other age-related declines in performance, such as a decrease in range of motion. This article is a part of a bigger project which aims to better understand how older adults with RCTs compensate for the decreased strength, the decreased range of motion, and the pain that accompany this type of injury. It is anticipated that the results of this experiment will lead to more research toward better understanding how to treat patients with RCTs.
ContributorsFlores, Noah Mateo (Author) / Dounskaia, Natalia (Thesis director) / Vidt, Meghan (Committee member) / College of Health Solutions (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Introduction: Individuals with rotator cuff tears (RCT) have been found to compensate in their movement patterns by using lower thoracohumeral elevation angles during certain tasks, as well as increased internal rotation of the shoulder (Vidt et al., 2016). The leading joint hypothesis (LJH) suggests there is one leading joint that creates the foundation for the entire limb motion, and there are other subordinate joints that monitor the passive interaction torque (IT) and create a net torque (NT) aiding to limb motions required for the task. This experiment hopes to establish a better understanding of joint control strategies during a wide range of arm movements. Based off of the LJH, we hypothesize that when a subject has a rotator cuff tear, their performance of planar and three- dimensional motions should be altered not only at the shoulder, which is often the leading joint, but also at other joints on the arm such as the elbow and wrist.
Methods: There were 3 groups of participants: healthy younger adults (age 21.74 ± 1.97), healthy older adult controls (age 69.53 ± 6.85), and older adults with a RCT (age 64.33 ± 4.04). All three groups completed strength testing, horizontal drawing and pointing tasks, and three-dimensional (3D) activities of daily living (ADLs). Kinematic and kinetic variables of the arm were obtained during horizontal and 3D tasks using data from 13 reflective markers placed on the arm and trunk, 8 motion capture cameras, and Cortex motion capture software (Motion Analysis Corp., Santa Rosa, CA). During these tasks, electromyography (EMG) electrodes were placed on 12 muscles along the arm that affect shoulder, elbow, and wrist rotation. Strength testing tasks were measured using a dynamometer. All strength testing and 3D tasks were completed for three trials and horizontal tasks were completed for two trials.
Results: Results of the younger adult participants showed that during the forward portion of seven 3D tasks, there were four phases of different joint control mechanics seen in a majority of the movements. These phases included active rotation of both the shoulder and the elbow joint, active rotation of the shoulder with passive rotation of the elbow, passive rotation of the shoulder with active rotation of the elbow, and passive rotation of both the shoulder and the elbow. Passive rotation during movements was a result of gravitational torque (GT) on the different segments of the arm and IT caused as a result the multi-joint structure of human limbs. The number of tested participants for the healthy older adults and RCT older adults groups is not yet high enough to produce significant results and because of this their results are not reported in this article.
Discussion: Through the available results, multiple phases were found where one or both of the joints of the arm moved passively which further supports the LJH and extends it to include 3D movements. This article is a part of a bigger project which hopes to get a better understanding of how older adults adjust to large passive torques acting on the arm during 3D movements and how older adults with RCTs compensate for the decreased strength, the decreased range of motion (ROM), and the pain that accompany these types of tears. Hopefully the results of this experiment lead to more research toward better understanding how to treat patients with RCTs.
Methods: There were 3 groups of participants: healthy younger adults (age 21.74 ± 1.97), healthy older adult controls (age 69.53 ± 6.85), and older adults with a RCT (age 64.33 ± 4.04). All three groups completed strength testing, horizontal drawing and pointing tasks, and three-dimensional (3D) activities of daily living (ADLs). Kinematic and kinetic variables of the arm were obtained during horizontal and 3D tasks using data from 13 reflective markers placed on the arm and trunk, 8 motion capture cameras, and Cortex motion capture software (Motion Analysis Corp., Santa Rosa, CA). During these tasks, electromyography (EMG) electrodes were placed on 12 muscles along the arm that affect shoulder, elbow, and wrist rotation. Strength testing tasks were measured using a dynamometer. All strength testing and 3D tasks were completed for three trials and horizontal tasks were completed for two trials.
Results: Results of the younger adult participants showed that during the forward portion of seven 3D tasks, there were four phases of different joint control mechanics seen in a majority of the movements. These phases included active rotation of both the shoulder and the elbow joint, active rotation of the shoulder with passive rotation of the elbow, passive rotation of the shoulder with active rotation of the elbow, and passive rotation of both the shoulder and the elbow. Passive rotation during movements was a result of gravitational torque (GT) on the different segments of the arm and IT caused as a result the multi-joint structure of human limbs. The number of tested participants for the healthy older adults and RCT older adults groups is not yet high enough to produce significant results and because of this their results are not reported in this article.
Discussion: Through the available results, multiple phases were found where one or both of the joints of the arm moved passively which further supports the LJH and extends it to include 3D movements. This article is a part of a bigger project which hopes to get a better understanding of how older adults adjust to large passive torques acting on the arm during 3D movements and how older adults with RCTs compensate for the decreased strength, the decreased range of motion (ROM), and the pain that accompany these types of tears. Hopefully the results of this experiment lead to more research toward better understanding how to treat patients with RCTs.
ContributorsGarnica, Nicholas (Co-author) / Perrine, Austin (Co-author) / Schalk, Courtney (Co-author) / Dounskaia, Natalia (Thesis director) / Vidt, Meghan (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
As life expectancy continually rises, many age-related conditions such as deteriorated gait and decreased stability begin to play a larger role in affecting the quality of life for all individuals. Medical expenses associated with falls in the elderly population surpassed $50 Billion in 2015 alone. Understanding fall risk and developing robust metrics and methods of assessment has become more important than ever. While traditional fall risk has looked at classical gait parameters, dynamic stability has gained traction as a more accurate representation of stability during active movement and daily activities. This project seeks to determine the effects on the internal perturbation of gait velocity on dynamic stability represented by the Maximal Lyapunov Exponent (MLE) of multiple acceleration vectors, as well as the efficacy of varying methodology used to assess dynamic stability. Data from 15 healthy, college aged individuals was collected. Significant differences were shown between certain gait velocity trials for one analysis of the three methods explored, while overall trends suggested potential differences between gait velocities with other methodologies warranting further investigation.
ContributorsKreisler, Itai Goeta (Author) / Lockhart, Thurmon (Thesis director) / Rezvanian, Saba (Committee member) / W.P. Carey School of Business (Contributor) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Rotator cuff tears (RCT) can affect up to 50% of the older population and this injury is typically associated with functional deficits and shoulder pain that prevent people from living a typical lifestyle. Particularly in an older population, this type of pain increases functional dependency on others and can hinder the possibility of independent living. An area of shoulder pathology that lacks research is the functional differences in symptomatic and asymptomatic tears on activities of daily living (ADL). In order to more fully understand the functional presentations associated with each of these types of tears, it is critical that we evaluate the various mechanisms that contribute to altered movement patterns. Understanding these different compensatory patterns between asymptomatic and symptomatic tears will allow for a better understanding of the presentation of this shoulder pathology and provide new insight for diagnostic and rehabilitation purposes. Therefore, the objective of this study is to quantify kinematic differences of daily upper limb movements between symptomatic and asymptomatic RCTs in an older population. To accomplish this goal, we will be using motion capture and electromyography to assess typical ADL movements and their associated muscle activation patterns during 2D and 3D tasks in older adults (≥55 years). Strength and shoulder range of motion measures will also be taken, as well as self-reported measures of function and pain. Through this project, we seek to understand the presentation of RCTs and what characteristics are associated with symptoms. Long term, outcomes from this work will be used to develop a more standardized approach to early detection and treatment of this common shoulder pathology in the older adult population.
ContributorsFujita, Hikaru Ashley (Author) / Vidt, Meghan (Thesis director) / Dounskaia, Natalia (Committee member) / School of Nutrition and Health Promotion (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Research on joint control during arm movements in adults has led to the development of the Leading Joint Hypothesis (LJH), which states that the central nervous system takes advantage of interaction torque (IT) and muscle torque (MT) to produce movements with maximum efficiency in the multi-jointed limbs of the human body. A gap in knowledge exists in determining how this mature pattern of joint control develops in children. Prior research focused on the kinematics of joint control for children below the age of three; however, not much is known about interjoint coordination with respect to MT and IT in school-aged children. In the present study, joint control at the shoulder, elbow, and wrist during drawing of five shapes was investigated. A random sample of nine typically developing children ages 6 to 12 served as subjects. The task was to trace with the index finger a template placed on a horizontal table. The template consisted of a circle, horizontal, vertical, right-diagonal, and left-diagonal line. Analysis of muscle torque contribution (MTC) revealed the individual roles of MT and IT in the shoulder, elbow, and wrist joints. During drawing of the horizontal line, which requires the most difficult joint control pattern in adults because it does not allow the use of IT for joint rotation, joint control was found to change through development. For the youngest children, the function of elbow MT modified to suppress IT, thereby producing large elbow rotation. The oldest children simplified this by using the shoulder as the principal joint of movement production and with decreased assistance from the elbow. For the other four drawing movements, differences in the pattern of joint control used by all of the subjects was unaffected by an increase in age. Overall, the results suggest that in children above 6 years of age, minor changes in joint control occur during drawing of relatively simple movements. The limited effect of age that was observed could be related to the restriction of movements to the horizontal plane. For a future study, three-dimensional movements that provide more freedom in joint control due to redundancy of degrees of freedom could be more informative about developmental changes in joint coordination.
ContributorsKemmou, Nadaa (Co-author) / Way, Victoria (Co-author) / Dounskaia, Natalia (Thesis director) / Vidt, Meghan (Committee member) / School of Nutrition and Health Promotion (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Gait training therapies are methods for improving the walking stability of individuals who have difficulty walking, whether it is due to injury or neuromuscular conditions. Perturbation training that causes individuals to correct their balance and actively improve their stability could potentially lead to longer term benefits for those with unstable gait. Subjects had the medial lateral movement of their center of mass measured through motion-tracking software (D-Flow 3 and Vicon Nexus 2.2). Perturbation training completed with the GRAIL treadmill randomly triggered medial-lateral sway perturbations of 3 cm a total of fifteen times throughout a five minute training period. Data collected to compare baseline, post-training, and one week follow-up dynamic stabilities were recorded over three minutes without any perturbations. There were no statistically significant differences when comparing the results of all subjects at each instance of data collection with each other. Thus, the perturbation training had no significant impact on the dynamic stability of gait. Major limitations that lend to the inconclusive nature of this study include a small sample size, no repetitions, and only one round of training. Further work can be done to better assess the potential impacts of perturbation training on walking stability for therapeutic use.
ContributorsJamali, Neema (Author) / Lockhart, Thurmon (Thesis director) / Soangra, Rahul (Committee member) / School of Biological and Health Systems Engineering (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05