Impairments in walking for older healthy adults and poststroke individuals develop due to poor neuromotor control, albeit from very different mechanisms. There is a need to identify measures of neuromotor function that are sensitive to different degrees of locomotor impairment and that may be more useful to distinguish between recovery (vs. compensation) with rehabilitation. This project investigates the ability of muscle synergies, dynamic motor control index for walking, and central drive to identify motor control impairments. Moreover, the relationship between these measures is evaluated to determine if they measure complementary or different aspects of neuromotor control.  

Central drive to the paretic plantarflexors is associated with propulsion ability post-stroke and has potential to be a biomarker of neuromotor impairment and rehabilitative capacity. Though central drive-based biomarkers of neuromotor impairment are promising, clinical adoption is hindered because gold-standard stationary dynamometers are costly and not widely available. Our team has developed a portable plantarflexor force-measurement device with the goal of increasing clinician access to plantarflexor central drive measurements. 

To date we've demonstrated that during use of a soft robotic exosuit that provides plantar and dorsiflexion assistance there are immediate 
improvements in spatiotemporal asymmetries, propulsion asymmetries, and compensation patterns. This project focuses on the neural control aspect, primarily muscle synergies and central drive ratios, to determine if the exosuit is having an impact on the neuromuscular system and has potential for long-term rehabilitation in addition to its capabilities as an assistive device.

It’s been shown that when listening to music while walking, humans naturally change their cadence to match the beat. The Neuromotor Recovery Lab has partnered with MedRhythms Inc. to test their digital therapeutic platform which delivers a rhythmic training for individuals post-stroke.  Using popular songs, the MedRhythms device systematically alters the beat of the music so that the user increases their speed. If the user struggles to match the beat, a metronome is overlaid or the speed is slowed down. We have evaluated the impact of both single and multi-session training with this device on walking outcomes. 

Powered assistive technologies have proven to be useful in post-stroke walking both overground and on the treadmill. However, these technologies are not currently able to assist in all mobility tasks, particularly those outside the lab. This is partially due to lack of seamless transition between assistance modes for each task. To do this, we must be able to accurately track a person's movement and predict what will happen next. While this is a long-term goal, our team is developing a multi-modal system to accurately track individuals using an external depth camera and minimal inertial sensor set. We are validating this against the "gold-standard" motion capture system and using it to develop an automatic scoring system for common clinical tests. 

Cerebral palsy (CP) leads to impaired limb function that reduces mobility and coordination. Balance training during developmental years improves walking ability and overall mobility. Currently, a free-falling wobble board is used for balance training, however children with CP have roughly 45% of the reaction time of a healthy adult and are unable to use the device without intervention from a physical therapist. We developed a smart balance trainer for children with CP that aims to improve their balance and muscle strength by varying speed and maximum tilt angle. Project completed May 2017. 

Global Biomedical Service (GBS) is an annual program run by the University of Pennsylvania, Washington University in St. Louis, and the Hong Kong Polytechnic University. The program consists of an 8-week course and a 2-week trip where we apply our engineering skills in a clinical environment. When I completed the program in 2015 we traveled to Heyuan, China to develop ankle-foot orthoses for children with
cerebral palsy. Project completed May 2015.