In the United States, more than 18 million people suffer from upper extremity injury. This population is in need of a device both to aid in the completion of activities of daily living (eating and grooming), as well as to provide daily muscular therapy. To assist persons suffering from disabling upper extremity neuromuscular diseases, this thesis concerned the redesign of a powered arm brace from a proof-of-concept design to a more functional, marketable product. The principles of Design for Manufacturability and Assembly (DFMA) were employed as part of the design methodology to create a product that could be scaled into production. Additionally, numerical analyses including Finite Element Analysis (FEA) were completed to prove the both the safety and structural integrity of the orthosis in computer simulations. The design was then successfully tested with marked improvement over the previous design, including a 58% reduction in weight, decreased manufacturing costs, and a significant improvement in functionality and comfort.

Introduction Post-stroke activity limitation secondary to upper-extremity motor impairment is common, and increasing. We do not currently have effective, globally applicable interventions to improve activity limitation. The burden of post-stroke disability is rising in low and middle-income countries, resulting in an immediate need for effective interventions that can be implemented throughout the world. Purpose This program of research was structured to address three important questions, 1) In all parts of the world, do people with stroke experience similar degrees of activity limitation secondary to upper extremity motor impairment? 2) Are there simple interventions that can be initiated by health care workers, but autonomously sustained by people with stroke, that can improve activity limitation secondary to upper extremity motor impairment? and 3) Are these interventions effective? Methods To address the first question, data from an international stroke study were used to quantify the amount of post-stroke upper extremity weakness and characterize the people. For the second question, a systematic review was conducted to identify current evidence on the effectiveness of simple, task-based practice. To address the third question a protocol was developed for an outcome study. Results Post-stroke upper extremity weakness is common throughout the world, ranging from 67.3% of those with stroke in high-income countries to 97.3% in low-income countries. There is inconclusive, but promising evidence on the effectiveness of simple, task-based practice to improve upper-extremity motor impairment. It is likely that multiple interventions are needed to address the problem and a two-by-two factorial design trial, evaluating simple, task-based practice or a motor enhancing pharmacological agent, implemented in all regions of the world, would be a novel and efficient means of addressing the question. Conclusions The answers to these questions have provided novel information that is a required next step to providing effective, globally applicable interventions for people with stroke. / Thesis / Doctor of Philosophy (PhD) / After having a stroke, more than half the people have difficulty moving their arm. This difficulty often results in difficulties doing every day tasks. Most of the information on what happens after stroke comes from developed countries and we do not know if these problems exist to the same extent in developed countries. We also do not know the most effective interventions to help improve arm function after stroke. Possible interventions could include rehabilitation strategies, drugs or a combination of both. This thesis describes the amount of arm weakness after stroke throughout the world, looks at the evidence for a simple intervention that could be used throughout the world, and describes the design of study that could look at the effectiveness of both rehabilitation and drug interventions throughout the world. This work provides information on the globally applicable interventions to improve arm function after stroke, which has not been considered in the literature to date.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Cartas al editor / Revisión por pares / Revisón por pares

Analysis techniques specific to the proximal upper extremity have historically been overlooked in the field of ergonomics. This research effort provides a methodology that will allow the ergonomics practitioner to analyze a job and predict whether or not that job exposes workers to increased risk of proximal upper extremity disorders. Literature from the fields of physiology, biomechanics, and epidemiology was assimilated in order to understand the theories of pathogenesis of disorders in the rotator cuff and to identify the risk factors associated with proximal upper extremity disorders. A retrospective epidemiological study was conducted to identify job task variables that may contribute to the occurrence of proximal upper extremity disorders. Two proximal upper extremity constructs were proposed: a fatigue-based model and a compressive load-based model. The constructs incorporated lessons learned from the literature and results from the epidemiological study. Validation of the models was performed using data from the epidemiological study. It was determined that the fatigue-based model was a good predictor of proximal upper extremity disorders.

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Occupational Therapy. Johannesburg, 2017 / Introduction: Lycra compression garments have been documented as beneficial in affecting spasticity in children with cerebral palsy but there is little research on the use of Lycra compression garments in adults with neurological conditions. Thus, the purpose of this study was to explore the effectiveness of Lycra compression garments on motor function and functional use of the upper limb, in patients with stroke. Methods: A randomised control design with a control or intervention group was used. Both groups received routine upper limb rehabilitation while the experimental group also received a custom Lycra compression garment worn for a minimum of six hours a day. Results: Change between an initial assessment and assessment at six weeks, was measured on the Fugl-Meyer Assessment of Motor Recovery (FMA) and The Disabilities of the Arm, Shoulder and Hand Outcome Measure (DASH). While both groups had significant improvement in upper limb movement, statistically significant differences for change in total motor function, wrist and hand movement and coordination were found when the experimental group and the control group were compared. Small differences in measurements of pain, passive range of motion, sensation and functional use of the upper limb were found between the two groups. Conclusion: Results indicate that Lycra compression garments may be beneficial in facilitating the return of movement in the upper limb in individuals with stroke. / MT2017

<p>The aim of this study was to understand injury mechanisms behind fractures of the upper extremities in car accidents. Volvo Car Corporation initiated this project based on the fact that no safety system today focuses on preventing injuries to the upper extremity. A literature study was undertaken focusing on the basic anatomy of the upper extremity, different fracture types and fracture mechanisms. Three subsets, from 1998 – January 2009, were selected from Volvo’s statistical accident database: 1) all occupants involved in an accident 2) all occupants with a MAIS2+ injury 3) all occupants with an upper extremity fracture. These subsets were used in a comparison, using frequency analyses. The comparison analysis showed that frontal impact is the dominating accident type for all three subsets. The comparison analysis also indicated that the risk for upper extremity fractures follows the pattern of MAIS2+ injury risk. An in-depth study using 92 selected cases, including 80 occupants, was also performed. All available information, such as medical records, questionnaires completed by the occupants and photographs from the accident scene was collected and analysed. The analysis of the in-depth study, together with knowledge retrieved from the literature study, resulted in six different mechanism groups that were used to categorise fractures. The groups were then analysed individually in regard to accident type and fractured segment of the upper extremity. Analysis of the mechanism groups showed that frontal impact is the dominating accident type in these subsets as well. It could also be seen that the fractures occurring in the in-depth study are quite evenly distributed along the upper extremities. Upper extremity injuries are relatively infrequent in car accidents but may result in long-term disability, including chronic deformity, pain, weakness and loss of motion. More attention is therefore necessary in order to develop a safer environment for car occupants.</p>

The aim of this study was to understand injury mechanisms behind fractures of the upper extremities in car accidents. Volvo Car Corporation initiated this project based on the fact that no safety system today focuses on preventing injuries to the upper extremity. A literature study was undertaken focusing on the basic anatomy of the upper extremity, different fracture types and fracture mechanisms. Three subsets, from 1998 – January 2009, were selected from Volvo’s statistical accident database: 1) all occupants involved in an accident 2) all occupants with a MAIS2+ injury 3) all occupants with an upper extremity fracture. These subsets were used in a comparison, using frequency analyses. The comparison analysis showed that frontal impact is the dominating accident type for all three subsets. The comparison analysis also indicated that the risk for upper extremity fractures follows the pattern of MAIS2+ injury risk. An in-depth study using 92 selected cases, including 80 occupants, was also performed. All available information, such as medical records, questionnaires completed by the occupants and photographs from the accident scene was collected and analysed. The analysis of the in-depth study, together with knowledge retrieved from the literature study, resulted in six different mechanism groups that were used to categorise fractures. The groups were then analysed individually in regard to accident type and fractured segment of the upper extremity. Analysis of the mechanism groups showed that frontal impact is the dominating accident type in these subsets as well. It could also be seen that the fractures occurring in the in-depth study are quite evenly distributed along the upper extremities. Upper extremity injuries are relatively infrequent in car accidents but may result in long-term disability, including chronic deformity, pain, weakness and loss of motion. More attention is therefore necessary in order to develop a safer environment for car occupants.

To achieve expressive musical results in violin bowing, performers access wide ranges of combined musical tone loudness and duration variables. By comparison, allowable mechanical variability in bow stroke execution may be limited. Such constraints on string bowing variability similarly might limit variability of bowing limb movement. Constrained variability may carry risk of upper extremity musculoskeletal disorders. Therefore if musical and/or bowing-execution variables influence bowing limb movement variability, they may in turn influence risk of cumulative injury in the player. In two experimental studies we examined the influence of the musical variables of duration and sound intensity (loudness) on variability in both string bowing mechanical variables and bowing limb joint moments (i.e. rotational forces) and joint angle trajectories. Five violinists performed playing tasks in which bow strokes varied across four levels of duration and three levels of loudness. Given a constant-amplitude bow stroke, quiet, brief strokes and loud, long strokes had to be executed close to the lower and upper limits of permissible bow-on-string force (bow force). In Study #1, we computed one- and three-dimensional bow movement variance measures, in both kinematic (bow velocity across violin string, distance from bow-to-bridge) and kinetic (bow force) variables. In Study #2 we computed the cycle-to-cycle standard deviation of joint moments and angles for each moment and angular degree of freedom in the bowing limb. In each study, these variability measures were compared across the 12 experimental conditions. We hypothesized that variability would be lowest when executing quiet/brief and loud/long strokes, compared to strokes that could be executed further from bow force limits. However, it was also anticipated that variability instead could be influenced most strongly by bow and/or limb velocity, magnitude of bow force, and/or bowed-string loudness response properties. Results from both studies indicated that variability in both bow-on-string and limb movement was conditioned on these latter properties: tone duration and loudness exerted consistent effects on variances and standard deviations. Contradicting the main hypothesis, variability was not influenced by proximity to bow force limits. We conclude that bowing variability is constrained mainly by factors not specific to variability tolerance at the bow-violin string interface.

The deformation associated with a ballistic shield defeating a projectile can interact with the user’s upper extremity, resulting in the release of the shield, placing those behind the device at risk. This injury mechanism is known as behind-shield blunt trauma (BSBT). Previous studies investigating these interactions have used testing conditions not representative of those present during these behind-shield events and lacked sufficient testing to determine statistically relevant outcomes. In the present work, the loading present during ballistic shield deformation was characterized through testing using an Anthropomorphic Test Device (ATD) upper extremity placed behind a level III ballistic shield. Digital image correlation (DIC) and post-impacting X-ray imaging were used to assess the ballistic shield’s deformation. The data collected from ballistic testing informed the development of a projectile used with a pneumatic impactor for the application of BSBT in a lab-based setting. Using the projectile, ballistic impacts were replicated on the ATD upper extremity and translated to 5th and 95th percentile cadaveric arms. Load data were collected for the hand and forearm using piezoelectric force sensors embedded in the projectile. Similarly, PMHS were impacted in a stepwise fashion of increasing energy until fractures were identified using X-ray imaging. A novel scaling technique was developed where Partial Least Squares (PLS) was used to determine critical variables relating donor anthropometrics to peak impact force. The scaling equations generated using this technique offer future researchers the opportunity to employ a larger range of specimens when determining injury thresholds for the hand and forearm. Through the characterization of the conditions present during BSBT, the injury thresholds to these mechanisms were assessed for understudied populations. Additionally, this work presents scaling techniques that could reduce the number of specimens required to determine future upper extremity injury limits. The information presented within this work provides an important step in developing new standards for ballistic shields to better protect users from BSBT. / Thesis / Master of Applied Science (MASc) / The deformation of a ballistic shield associated with stopping a bullet can interact with the user’s arm, causing them to drop the shield and placing the user in further danger. This work aimed to assess the risks to the hand and forearm over a range of male sizes using mechanical and biomedical tools. Ballistic loading was characterized using a crash test dummy arm to understand the conditions present during the event. The injuries associated with this loading were assessed using cadaveric specimens and a custom projectile for replicating the impacts. Mathematical techniques were used to translate the injury thresholds to the exact user sizes – providing relevant metrics for future ballistic shield standards. The results of this work present methods for recreating ballistic testing in a lab-based setting and for scaling forces associated with the hand and forearm, allowing future researchers to use a broader range of specimens for injury assessment.

This paper describes a three part analysis to characterize the interaction between the female upper extremity and a helicopter cockpit side airbag system and to develop dynamic hyperextension injury criteria for the female elbow joint. Part I involved a series of 10 experiments with an original Army Black Hawk helicopter side airbag. A 5th percentile female Hybrid III instrumented upper extremity was used to demonstrate side airbag upper extremity loading. Two out of the 10 tests resulted in high elbow bending moments of 128 Nm and 144 Nm. Part II included dynamic hyperextension tests on 24 female cadaver elbow joints. The energy source was a drop tower utilizing a three-point bending configuration to apply elbow bending moments matching the previously conducted side airbag tests. Post-test necropsy showed that 16 of the 24 elbow joint tests resulted in injuries. Injury severity ranged from minor cartilage damage to more severe joint dislocations and transverse fractures of the distal humerus. Peak elbow bending moments ranged from 42.4 Nm to 146.3 Nm. Peak bending moment proved to be a significant indicator of any elbow injury (p=0.02) as well as elbow joint dislocation (p=0.01). Logistic regression analyses were used to develop single and multivariate injury risk functions. Using peak moment data for the entire test population, a 50% risk of obtaining any elbow injury was found at 56 Nm while a 50% risk of sustaining an elbow joint dislocation was found at 93 Nm for the female population. These results indicate that the peak elbow bending moments achieved in Part I are associated with a greater than 90% risk for elbow injury. Subsequently, the airbag was re-designed in an effort to mitigate this as well as the other upper extremity injury risks. Part III assessed the enhanced side airbag module to ensure injury risks had been reduced prior to implementing the new system. To facilitate this, 12 enhanced side airbag deployments were conducted using the same procedures as Part I. Results indicate that the re-designed side airbag has effectively mitigated elbow injury risks induced by the original side airbag design. It is anticipated that this study will provide researchers with additional injury criteria for assessing upper extremity injury risk caused by both military and automotive side airbag deployments. / Master of Science