Research

Our expertise is in the neuromuscular biomechanics of human movement, with a special emphasis on aging and disease-related mobility impairment. Our primary research seeks to discover the musculoskeletal and sensorimotor adaptations that underlie a loss of independent mobility, and to introduce creative new approaches for preserving walking ability and preventing falls. We use a highly integrative approach that combines quantitative motion analysis, electromyography, biomedical imaging, and computational simulation.

At any given time, we have numerous active and ongoing research projects being conducted in our laboratory. Many of these are highly inter-disciplinary and performed in collaboration with colleagues in Exercise and Sports Science, Physical Therapy, Orthopaedics, Biostatistics, Neurology, Geriatrics, Public Health, and Neurosurgery. Ultimately, our research seeks to address four pivotal challenges faced by those in our older adult population:

SELECT PROJECTS

Evaluating wearable robotics for enhanced mobility, walking capacity, and endurance

Wearable ankle exoskeletons, especially when designed to operate collaboratively with underlying muscle mechanics, have the potential to augment walking performance in individuals with insufficient push-off intensity. When assisting push-off, these devices can offload the calf muscles with potential to reduce metabolic energy cost, and improve walking endurance, and – by increasing propulsive capacity – improve community accessibility. However, potential contraindications come from assistance accelerating the effects of muscle disuse. Conversely, therapeutic designs that resist push-off, which we are evaluating in conjunction with real-time ankle power biofeedback to promote engagement, have the potential to enhance calf muscle performance and functional mobility over time. We have several lines of research testing various hypotheses related to these aspects of human-machine interaction.

Perturbation systems to characterize neuromuscular vulnerability, instability, and falls

We have developed a suite of sensory and mechanical balance perturbation systems designed to emulate balance challenges that may precipitate a fall in the community. These include immersive virtual reality environments, motor-driven force fields, treadmill-induced slip controllers, and computer-guided laser projection systems. We consistently have several lines of research designed to leverage this infrastructure to gain previously inaccessible insight into standing and walking instability due to age or neurodegenerative disease..

Revolutionizing our understanding of knee joint neuromechanics to determine risk factors and treatment options for post-traumatic and age-related osteoarthritis.

Our laboratory houses the only high-speed biplane videoradiography system at any public institution in the state of North Carolina, enabling cutting edge investigations into joint arthrokinematics and pathophysiology. We formally integrate these experimental measurements with computational simulations of joint neuromechanics in a highly collaborative environment, revolutionizing our understanding of degenerative joint conditions.

Wearable sensing to enable remote monitoring of walking performance, joint health, instability, and clinical outcomes.

The field of biomechanics is undergoing a significant shift toward the use of wearable sensing and computer vision technologies to promote translational research beyond the laboratory. We are leveraging these emerging technologies across several lines of research to include: (1) quantifying harmful patterns of joint loading relevant to the onset and progression of knee osteoarthritis, (2) developing sensitive wearable biomarkers for diagnostics and remote monitoring of instability and falls, and (3) characterizing functional mobility outcomes following neurosurgical intervention.

A framework for feasible translation to enhance foot neuromechanics in aging and mobility

We are investigating the extent to which hallmark age-associated deficits in push-off intensity during walking originate interdependently with those in the active, passive, and structural regulation of foot mechanical power. The goal of this project is to establish a much-needed paradigm shift in our biomechanical understanding and clinical management of age-related mobility impairment toward feasible and cost-effective devices to modify foot structure and function in aging

Characterizing the origins, time course, and functional consequences of local muscle and walking-related fatigability.

We have several lines of research using novel experimentation and sophisticated surface and indwelling electromyographic analyses to understand the ways in which fatigability affects multiple domains of physical function, to include mobility, agility, and stability. From isolated gluteus medius, calf, and plantar intrinsic muscle fatiguing protocols to prolonged walking protocols, we are simultaneously using this information to develop and test strategies and devices to promote fatigue resistance and thereby enhanced independence.

Examining structure-function relations, anatomical heterogeneity, and clinical outcomes for Achilles tendon health

Achilles tendinopathy is a painful and debilitating condition that results in inflammation, stiffness and difficulty walking. Exercise therapy is a gold standard treatment of the condition, but has a high recurrence rate in nearly half of all patients with this diagnosis. The Achilles tendon connects the heel to three separate muscles in an anatomical arrangement that varies between people, resulting in a complex anatomy that may lead to this inconsistency in success rates with current treatment. By combining high-field MRI, in vivo cine ultrasound imaging, quantitative movement analysis, and computational modeling, we seek to guide personalized clinical interventions to better support patients with this painful condition.