Human Health Engineering Volume II

In this Special Issue on “Human Health Engineering Volume II”, we invited submissions exploring recent contributions to the field of human health engineering, i.e., technology for monitoring the physical or mental health status of individuals in a variety of applications. Contributions could focus on sensors, wearable hardware, algorithms, or integrated monitoring systems. We organized the different papers according to their contributions to the main parts of the monitoring and control engineering scheme applied to human health applications, namely papers focusing on measuring/sensing physiological variables, papers highlighting health-monitoring applications, and examples of control and process management applications for human health. In comparison to biomedical engineering, we envision that the field of human health engineering will also cover applications for healthy humans (e.g., sports, sleep, and stress), and thus not only contribute to the development of technology for curing patients or supporting chronically ill people, but also to more general disease prevention and optimization of human well-being

Neuroplasticity of Ipsilateral Cortical Motor Representations, Training Effects and Role in Stroke Recovery

This thesis examines the contribution of the ipsilateral hemisphere to motor control with the aim of evaluating the potential of the contralesional hemisphere to contribute to motor recovery after stroke. Predictive algorithms based on neurobiological principles emphasize integrity of the ipsilesional corticospinal tract as the strongest prognostic indicator of good motor recovery. In contrast, extensive lesions placing reliance on alternative contralesional ipsilateral motor pathways are associated with poor recovery. Within the predictive algorithms are elements of motor control that rely on contributions from ipsilateral motor pathways, suggesting that balanced, parallel contralesional contributions can be beneficial. Current therapeutic approaches have focussed on the maladaptive potential of the contralesional hemisphere and sought to inhibit its activity with neuromodulation. Using Transcranial Magnetic Stimulation I seek examples of beneficial plasticity in ipsilateral cortical motor representations of expert performers, who have accumulated vast amounts of deliberate practise training skilled bilateral activation of muscles habitually under ipsilateral control. I demonstrate that ipsilateral cortical motor representations reorganize in response to training to acquisition of skilled motor performance. Features of this reorganization are compatible with evidence suggesting ipsilateral importance in synergy representations, controlled through corticoreticulopropriospinal pathways. I demonstrate that ipsilateral plasticity can associate positively with motor recovery after stroke. Features of plastic change in ipsilateral cortical representations are shown in response to robotic training of chronic stroke patients. These findings have implications for the individualization of motor rehabilitation after stroke, and prompt reappraisal of the approach to therapeutic intervention in the chronic phase of stroke

The contemporary model of vertebral column joint dysfunction and impact of high-velocity, low-amplitude controlled vertebral thrusts on neuromuscular function

Peer reviewedPublisher PD

Exploring the role of interhemispheric inhibition in musculoskeletal pain

The overarching aim of this thesis was to determine whether: i) interhemispheric inhibition (IHI) is altered in response to unilateral musculoskeletal pain; and ii) a relationship exists between altered IHI (if any) and the development of bilateral sensorimotor dysfunction. To achieve this, three studies were conducted. These studies provided novel insight into IHI in experimentally induced acute muscle pain and chronic lateral elbow pain. The body of work in this thesis provides an original contribution to the field of musculoskeletal pain that deepens our understanding of IHI, and its potential association with changes in sensorimotor function in the unaffected limb, in unilateral conditions. Study 1 demonstrated a reduction in IHI from the affected to unaffected M1 but no change in IHI from the affected to unaffected S1 was observed in Study 2. In both studies, increased sensitivity to pressure was observed on the affected and unaffected sides. No change in IHI between M1s, and no differences in sensorimotor function were observed between individuals with chronic LE and healthy controls in Study 3. Taken together, the findings presented in this thesis suggest that IHI between M1s is reduced in response to acute muscle pain and altered IHI could contribute to the development of bilateral sensorimotor symptoms soon after pain onset. Conversely, IHI between S1s is preserved in response to acute muscle pain. In a clinical chronic musculoskeletal pain population, IHI is also preserved. However, further research is needed to determine whether the degree of change in IHI is related to various features of clinical pain such as pain severity, or the severity of bilateral sensorimotor dysfunction. The studies in this thesis are amongst the first to investigate: i) IHI in response to musculoskeletal pain of varying durations; and ii) the relationship between altered IHI and the development of bilateral sensorimotor dysfunction. Longitudinal studies that follow individuals from an initial episode of acute musculoskeletal pain to recovery, or to the development of chronic musculoskeletal pain, are required to further explore the relationship between IHI and the development of bilateral sensorimotor symptoms in unilateral musculoskeletal pain conditions

Evaluating footwear “in the wild”: Examining wrap and lace trail shoe closures during trail running

Trail running participation has grown over the last two decades. As a result, there have been an increasing number of studies examining the sport. Despite these increases, there is a lack of understanding regarding the effects of footwear on trail running biomechanics in ecologically valid conditions. The purpose of our study was to evaluate how a Wrap vs. Lace closure (on the same shoe) impacts running biomechanics on a trail. Thirty subjects ran a trail loop in each shoe while wearing a global positioning system (GPS) watch, heart rate monitor, inertial measurement units (IMUs), and plantar pressure insoles. The Wrap closure reduced peak foot eversion velocity (measured via IMU), which has been associated with fit. The Wrap closure also increased heel contact area, which is also associated with fit. This increase may be associated with the subjective preference for the Wrap. Lastly, runners had a small but significant increase in running speed in the Wrap shoe with no differences in heart rate nor subjective exertion. In total, the Wrap closure fit better than the Lace closure on a variety of terrain. This study demonstrates the feasibility of detecting meaningful biomechanical differences between footwear features in the wild using statistical tools and study design. Evaluating footwear in ecologically valid environments often creates additional variance in the data. This variance should not be treated as noise; instead, it is critical to capture this additional variance and challenges of ecologically valid terrain if we hope to use biomechanics to impact the development of new products

Spinal Cord Injury and Transcutaneous Spinal Cord Stimulation

Recent research of epidural and transcutaneous electrical spinal cord stimulation has demonstrated unprecedented improvements in motor function thought to be irreversibly lost due to chronic, severe spinal cord injury. Studies in parallel assess these methods for spasticity management as an alternative to medications that are often accompanied by deleterious side effects. As a noninvasive intervention, transcutaneous spinal cord stimulation holds the great potential to find its way into wide clinical application. Its firm establishment and lasting acceptance as clinical practice in spinal cord injury will not only hinge on the demonstration of safety and efficacy, but also on the delineation of a conceptual framework of the underlying physiological mechanisms. This will also require advancing our understanding of immediate and temporary effects of transcutaneous spinal cord on neuronal circuits in the intact and injured spinal cord. The purpose of this collection of papers is to bring together peers in the field to share—and eventually fuse—their pertinent research into current neurorehabilitation practice by providing a clinical perspective and novel insights into the underlying mechanisms