Lise Worthen-Chaudhari

Poststroke upper extremity rehabilitation: a review of robotic systems and clinical results.

Abstract Although the use of robotic devices to address neuromuscular rehabilitative goals represents a promising technological advance in medical care, the large number of systems being developed and varying levels of clinical study of the devices make it difficult to follow and interpret the results in this new field. This article is a review of the current state-of-the-art in robotic applications in poststroke therapy for the upper extremity, written specifically to help clinicians determine the differences between various systems. We concentrate primarily on systems that have been tested clinically. Robotic systems are grouped by rehabilitation application (e.g., gross motor movement, bilateral training, etc.), and, where possible, the neurorehabilitation strategies employed by each system are described. We close with a discussion of the benefits and concerns of using robotics in rehabilitation and an indication of challenges that must be addressed for therapeutic robots to be applied practically in the clinic.

Proof of Concept of the Ability of the Kinect to Quantify Upper Extremity Function in Dystrophinopathy

Introduction: Individuals with dystrophinopathy lose upper extremity strength in proximal muscles followed by those more distal. Current upper extremity evaluation tools fail to fully capture changes in upper extremity strength and function across the disease spectrum as they tend to focus solely on distal ability. The Kinect by Microsoft is a gaming interface that can gather positional information about an individual’s upper extremity movement which can be used to determine functional reaching volume, velocity of movement, and rate of fatigue while playing an engaging video game. The purpose of this study was to determine the feasibility of using the Kinect platform to assess upper extremity function in individuals with dystrophinopathy across the spectrum of abilities. Methods: Investigators developed a proof-of-concept device, ACTIVE (Abilities Captured Through Interactive Video Evaluation), to measure functional reaching volume, movement velocity, and rate of fatigue. Five subjects with dystrophinopathy and 5 normal controls were tested using ACTIVE during one testing session. A single subject with dystrophinopathy was simultaneously tested with ACTIVE and a marker-based motion analysis system to establish preliminary validity of measurements. Results: ACTIVE proof-of-concept ranked the upper extremity abilities of subjects with dystrophinopathy by Brooke score, and also differentiated them from performance of normal controls for the functional reaching volume and velocity tests. Preliminary test-retest reliability of the ACTIVE for 2 sequential trials was excellent for functional reaching volume (ICC=0.986, p<0.001) and velocity trials (ICC=0.963, p<0.001). Discussion: The data from our pilot study with ACTIVE proof-of-concept demonstrates that newly available gaming technology has potential to be used to create a low-cost, widely-accessible and functional upper extremity outcome measure for use with children and adults with dystrophinopathy.

A feasibility study using interactive graphic art feedback to augment acute neurorehabilitation therapy

BACKGROUND Interactive arts technologies, designed to augment the acute neurorehabilitation provided by expert therapists, may overcome existing barriers of access for patients with low motor and cognitive function. OBJECTIVES Develop an application prototype to present movement feedback interactively and creatively. Evaluate feasibility of use within acute neurorehabilitation. METHODS Record demographics and Functional Independent Measure™ scores among inpatients who used the technology during physical, occupational or recreational therapy. Record exercises performed with the technology, longest exercise duration performed (calculated from sensor data), user feedback, and therapist responses to a validated technology assessment questionnaire. RESULTS Inpatients (n = 21) between the ages of 19 and 86 (mean 57 ± 18; 12 male/9 female) receiving treatment for motor deficits associated with neuropathology used the application in conjunction with occupational, recreational, or physical therapy during 1 to 7 sessions. Patients classified on the Functional Independence Measure™ as requiring 75%+ assistance for cognitive and motor function were able to use the interactive application. CONCLUSIONS Customized interactive arts applications are appropriate for further study as a therapeutic modality. In addition to providing interactivity to individuals with low motor function, interactive arts applications might serve to augment activity-based medicine among inpatients with low problem-solving and memory function.

A new look at an old problem: Defining weight acceptance in human walking

BACKGROUND Weight acceptance (WA) is an important phase of bipedal gait that has received relatively little study to date. This study tested the hypothesis that the first peak knee flexion would better demarcate the end of WA power absorption activity across varying gait speeds than would the more commonly used event of contralateral toe off (CTO) or the peak hip adduction angle. METHODS Eight control subjects (4F/4M) walked on a treadmill at slow, self-selected, and fast speeds. Kinematic and kinetic data were recorded. Joint angles and power absorption were analyzed about the, lower extremity joints (sagittal ankle, knee, hip and frontal hip). Differences in event timings and, magnitudes of negative work were analyzed (ANOVA). RESULTS Knee sagittal power absorption continued after the CTO event at self-selected (p=0.009) and fast speeds (p=0.001), while hip frontal power absorption continued after the CTO event at slow (p=0.019), self-selected (p=0.001), and fast speeds (p=0.001). The contribution of frontal hip to overall power absorption increased as speed decreased. DISCUSSION Peak hip adduction angle is the best kinematic marker of the end of the WA phase, and peak knee flexion angle is the best alternative marker across speeds. CTO is only appropriate to use when gait speeds are slow. In addition, the relative contribution of power absorbed in the frontal hip during WA highlights the importance of frontal plane pelvic control in locomotion, especially when gait speed is slow.

Reducing concussion symptoms among teenage youth: Evaluation of a mobile health app

ABSTRACT Objective: To evaluate whether a mobile health application that employs elements of social game design could compliment medical care for unresolved concussion symptoms. Design: Phase I and Phase II (open-label, non-randomized, ecological momentary assessment methodology). Setting: Outpatient concussion clinic. Participants: Youth, aged 13–18 years, with concussion symptoms 3+ weeks after injury; Phase I: n = 20; Phase II: n = 19. Interventions: Participants received standard of care for concussion. The experimental group also used a mobile health application as a gamified symptoms journal. Outcome measures: Phase I: feasibility and satisfaction with intervention (7-point Likert scale, 1 high). Phase II: change in SCAT-3 concussion symptoms (primary), depression and optimism. Results: Phase 1: A plurality of participants completed the intervention (14 of 20) with high use (110 +/− 18% play) and satisfaction (median +/− interquartile range (IQR) = 2.0+/− 0.0). Phase II: Groups were equivalent on baseline symptoms, intervention duration, gender distribution, days since injury and medication prescription. Symptoms and optimism improved more for the experimental than for the active control cohort (U = 18.5, p = 0.028, effect size r = 0.50 and U = 18.5, p = 0.028, effect size r = 0.51, respectively). Conclusions: Mobile apps incorporating social game mechanics and a heroic narrative may promote health management among teenagers with unresolved concussion symptoms.

A Split-Crank Bicycle Ergometer Uses Servomotors to Provide Programmable Pedal Forces for Studies in Human Biomechanics

This paper presents a novel computer-controlled bicycle ergometer, the TiltCycle, for use in human biomechanics studies of locomotion. The TiltCycle has a tilting (reclining) seat and backboard, a split pedal crankshaft to isolate the left and right loads to the feet of the pedaler, and two belt-driven, computer-controlled motors to provide assistance or resistance loads independently to each crank. Sensors measure the kinematics and force production of the legs to calculate work performed, and the system allows for goniometric and electromyography signals to be recorded. The technical description presented includes the mechanical design, low-level software and control algorithms, system identification and validation test results.

Training conditions that best reproduce the joint powers of unsupported walking

OBJECTIVE To identify the clinically relevant combinations of body weight support and speed that best reproduce the joint powers of unsupported walking. METHODS Timing and magnitude of lower extremity joint powers were calculated for 8 neurologically intact volunteers (4M/4F) walking with 0%, 30% and 50% body weight support at three speeds (slow, comfortable, and fast). Lower extremity joint power absorption was analyzed during weight acceptance and forward propulsion. In addition, power generation was analyzed during forward propulsion. Timings and magnitudes of joint powers per condition were evaluated to identify the training combinations of body weight support and speed that best preserved the powers of unsupported walking at slow, comfortable and fast speeds. RESULTS For all speeds examined, increasing body weight support to 30% without changing speed provided the best match. In general, changes in speed disrupted the joint power magnitudes and timings more than application of body weight support. Increasing body weight support when faster training speeds were used proved a viable method for reproducing the joint powers of slow, unsupported walking. CONCLUSIONS These data provide a reference for understanding the effect of potential training conditions on power absorption and generation within the lower extremity joints during walking. It is possible to reproduce the joint powers of unsupported walking with certain combinations of body weight support and speed. We recommend applying adequate levels of BWS when training speeds are faster than the overground speed goal, as occurs during treadmill-based locomotor rehabilitation of individuals with incomplete spinal cord injury.

Characterizing within-subject variability in quantified measures of balance control: A cohort study

BACKGROUND To longitudinally assess individuals using quantified measures, we must characterize within-subject variability (WSV) of the measures. RESEARCH QUESTION What is the natural within-subject variability (WSV) that can be expected in postural control over 3+ days? METHODS Thirteen individuals without orthopedic or neurologic impairment (mean(SD) = 55 (9) years; 76 (18) kg; 11 females/2 males) were recruited from a community workplace and consented to participate. Participants stood quietly with eyes closed (QEC) on a force platform (5 x 1 min x 6 days) in two stances: comfortable and narrow. We recorded center of pressure (COP) and calculated COP-based balance parameters. To analyze variance components, we applied a linear mixed model for repeated measures, calculating within-subject standard deviation (SDws) from the pooled variance not attributable to between-subject variability. To estimate WSV, we scaled SDws by a confidence interval (CI) factor (e.g. WSV at the 95%CI = WSV95 = SDws * 1.96) and report WSV95 for a range of conditions previously reported in the literature and the following measures previously found sensitive to or predictive of health: (primary) WSV95 of root-mean square amplitude of medial-lateral COP during QEC (RMSml); (secondary) WSV95 of COP ellipse area (COPa); (secondary) WSV95 of mean medial-lateral COP velocity (COPvml) during QEC. RESULTS WSV95 was estimated at RMSml = 0.8 mm, COPa = 99mm2, and COPvml = 1.1 mm/s among healthy, middle-aged participants standing comfortably for one recommended data duration (4 × 30 s trials). A look up table provides values for alternate protocols that have been suggested in the literature and might prove relevant for clinical translation. SIGNIFICANCE This work advances longitudinal assessment of individuals using quantified measures of postural control. Results enable practitioners/researchers to assess an individuals progress, maintenance, or decline relative to WSV at a defined CI level.

Effectiveness, Usability, and Cost-Benefit of a Virtual Reality–Based Telerehabilitation Program for Balance Recovery After Stroke: A Randomized Controlled Trial

I have concerns about the level of detail provided regarding the design of visual feedback and exercise in the article by Llorens et al featured in the March issue of the Archives. I was excited to see an article about interactivity in the Archives, an area of study that has been called “interactive neurorehabilitation therapies”. The lack of sufficient information makes it difficult to interpret or cite this article appropriately. In addition, I am concerned that the article is categorized as a randomized controlled trial (RCT) when it does not seem to meet the definition. This study randomized participants with stroke into 2 groups. The one difference between the 2 groups was in the place where the virtual reality (VR)ebased training component was delivered: home or clinic. Both groups received an experimental treatment thrice a week: a VR application designed to treat balance. And both groups received a physical therapy regimen twice a week, which was intended to complement motor control but not train balance. The VR scheme for advancing difficulty and exercises provided were equivalent in both groups. The authors found comparable differences in Berg Balance Scale scores between both groups postintervention and call the study an RCT in the title. First, the information on visual feedback provided through the VR application is insufficient; some designs promote change better than others, and so without more information on the visual feedback provided, the reader cannot draw conclusions or compare results with those of other existing studies. Second, exercise design during the VR intervention is not sufficiently reported. Previous research has revealed that twolegged exercises coaching equal distribution of weight through some forms of visual feedback promote balance gains, but less is known about interactivity in combination with unilateral balance exercises. More detail about the type of exercises led by the VR application should have been disclosed so that the reader can assess whether the study reproduces previous findings or breaks new ground. Third, the authors do not sufficiently report on the physical therapy (PT) activity that occurred in addition to the VR application. Any weight-bearing activity requires balance skill; therefore, as stated, PT sessions that train skills “not related to balance to complement motor training” would theoretically have been limited to noneweight-bearing activity. As shown in another article featured