Wilmington Robotic Exoskeleton Research Articles

A Study On The Application Of Mobile Arm Support In Individuals With Cervical Cord Injuries

<h3>Research Objectives</h3> To investigate the change in the active range of motion (AROM) of the shoulder and elbow joints by applying the mobile arm support (MAS) in cervical injury patients with limitations in the proximal part of the upper extremities. Additionally, the user satisfaction with MAS was assessed. <h3>Design</h3> One group before-after trial. <h3>Setting</h3> Inpatients at the National Rehabilitation Center. <h3>Participants</h3> This study included five tetraplegic patients with at least one year since the onset and neurological level of injury at C3–C4 level. <h3>Interventions</h3> Participants were trained by applying the Wilmington Robotic Exoskeleton (WREX). Training was conducted based on the Jebsen–Taylor hand function test. Six sessions of the intervention were conducted for 30 minutes each, thrice a week for 2 weeks. <h3>Main Outcome Measures</h3> The AROM of the shoulder and elbow joints was measured. Additionally, Korean-Quebec User Evaluation of Satisfaction with Assistive Technology (K-QUEST) was used to evaluate the satisfaction. <h3>Results</h3> The AROM of the shoulder joint increased from 38.040±35.710° to 49.960±36.884° for flexion, 26.380±19.367° to 31.800±14.249° for extension, 18.980±12.765° to 21.340±14.570° for adduction, 44.180±24.547° to 53.620±24.253° for internal rotation, and 28.020±17.071° to 34.900±20.793° for external rotation, but without significant differences. The elbow joint showed no AROM change. K-QUEST assessed the satisfaction with the equipment, with a 5-point scoring system from 1 (not satisfied) to 5 (very satisfied). Most items showed a satisfaction level ≥4, confirming positive results with WREX. <h3>Conclusions</h3> MAS training in patients with chronic cervical injury demonstrated an increase in the AROM of the shoulder. Thus, MAS training can improve the upper extremity functions in cervical injury patients. Additionally, the K-QUEST results confirmed positive satisfaction with the WREX equipment in these patients. <h3>Author(s) Disclosures</h3> Jung-Eun Lim(1), Woo Yeung Kim(2), Onyoo Kim(2) (1)National Rehabilitation Research Institute, National Rehabilitation Center and Hospital, Seoul, South Korea (2)Department of Rehabilitation Medicine, National Rehabilitation Center and Hospital, Seoul, South Korea

Home Use of an Upper Extremity Exoskeleton in Children with SMA: A Pilot Study

Background: People with spinal muscular atrophy (SMA) often have arm weakness resulting in restricted independence and challenges with activities of daily living. An upper extremity (UE) orthosis, the Wilmington Robotic Exoskeleton (WREX), which augments arm movement by providing gravity assistance, was provided to a small cohort of subjects for 1 year. Resulting changes in the subjects’ performance were assessed.

Use of the Wilmington Robotic Exoskeleton to Improve Upper Extremity Function in Patients With Duchenne Muscular Dystrophy.

Patients with Duchenne muscular dystrophy in their second decade of life present with decreased upper extremity strength and active range of motion (AROM) that limit activities of daily living (ADLs). We evaluated the ability of the Wilmington Robotic Exoskeleton (WREX) to improve AROM and independence with ADLs. A retrospective chart review of 9 patients who trialed the WREX was performed. Patients were classified on the basis of the Brooke Upper Extremity Scale. AROM, strength, and independence with ADLs were assessed before and after a WREX trial. Patients demonstrated increased shoulder flexion and abduction (25°-100°, median = 55°) and elbow flexion (10°-110°, median = 60°). Increased independence with self-feeding, item retrieval, use of phones and tablets, and facial grooming were noted. The WREX allowed for gravity-reduced movement via elastic bands to unweight the upper extremity, enabling increased upper extremity active movement that supported increased independence with ADLs.

Quantitative measures with WREX usage.

This paper presents the results of two surveys conducted with users of a functional upper extremity orthosis called the Wilmington Robotic EXoskeleton (WREX). The WREX is a passive anti-gravity arm orthosis that allows people with neuromuscular disabilities to move their arms in three dimensions. An online user survey with 55 patients was conducted to determine the benefits of the WREX. The survey asked 10 questions related to upper extremity function with and without the WREX as well as subjective impressions of the device. A second survey used a phone interview based on the Canadian Occupational Performance Measure (COPM). Parents rated their child's performance and satisfaction while partaking in important activities both with and without the exoskeleton device. Scores were assessed for change between the two conditions. Twenty-five families responded to this survey. Twenty-four out of 25 subjects reported greater levels of performance and satisfaction when they were wearing the WREX. The mean change in performance score was 3.61 points, and the mean change in satisfaction score was 4.44 points. Results show a statistically significant improvement in arm function for everyday tasks with the WREX.

Outcome Measures with COPM of Children using a Wilmington Robotic Exoskeleton

Outcome Measures with COPM of Children using a Wilmington Robotic Exoskeleton

User Evaluation of a Dynamic Arm Orthosis for People With Neuromuscular Disorders.

This paper presents the results of an online survey conducted with users of a functional upper extremity orthosis called the Wilmington Robotic EXoskeleton (WREX). The WREX is a passive anti-gravity arm orthosis that allows people with neuromuscular disabilities to move their arms in three dimensions. The paper also describes the design of a novel lightweight 3-D printed WREX used for ambulatory children. Three different versions of the WREX are now offered to patients. Two can be mounted on a wheelchair and one to a body jacket for ambulatory patients. An online user survey with 55 patients was conducted to determine the benefits of the various WREXs. The survey asked ten questions related to upper extremity function with and without the WREX as well as subjective impressions of the device. Results show a statistically significant improvement in arm function for everyday tasks with the WREX.

Evaluation of an Arm Support With Trunk Motion Capability

Due to progressive muscle weakness, the arm function in boys with Duchenne muscular dystrophy (DMD) reduces. An arm support can compensate for this loss of function. Existing arm supports are wheelchair bound, which restricts the ability to perform trunk movements. To evaluate the function of a body-bound arm support, a prototype (based on the Wilmington robotic exoskeleton (WREX) arm support) that allows trunk movements was built. In order to examine the effect of this device and to compare it with an existing wheelchair-bound device, three healthy subjects performed single joint movements (SJMs) and activities of daily living (ADL) with and without the devices. The range of motion (RoM) of the arm and the surface electromyography (sEMG) signal of five different arm muscles were measured. The range of motion increased when compared to the wheelchair-bound device, and the trunk motion was perceived as important to make specific movements easier and more natural, especially the more extreme movements like reaching for a far object and reaching to the top of the head. The sEMG signal was comparable to that of the wheelchair-bound device. This means that an arm support with trunk motion capability can increase the range of motion of the user, while the amount of support to the arm is equal.

G.P.99 : The Wilmington Robotic Exoskeleton (WREX) improves upper extremity function in patients with Duchenne muscular dystrophy

Non-ambulatory patients with Duchenne muscular dystrophy (DMD) have arm weakness limiting anti-gravity movement resulting in severe functional impairments. The Wilmington Robotic Exoskeleton (WREX), by employing a unique 4bar link technology married with a variable linear elastic band power source, allows for 3 dimensional gravity reduced movement of the arms to enhance function for the completion of Activities of Daily Living (ADL). To establish the utility of WREX in patients with DMD, we report our experience from 2011 to 2014. Nine boys with DMD, aged 11–17y/o (median age 16y/o), were evaluated. Active range of motion (AROM) and functional task completion (self-feeding, drinking from a glass, access to face for grooming, manage eyeglasses, and access their environment, computer, cell phone, and other technology) were completed both with and without the WREX. AROM (without WREX/with WREX) was the following: shoulder flexion 0–30 degrees/45–100 degrees, shoulder abduction 0–30 degrees/45–100 degrees, and elbow flexion was 0–100 degrees/80–120 degrees. With the WREX, all patients demonstrated increased functional skills, especially the ability to self-feed, access joystick, access face for grooming, and reach away from the body to use technology. We conclude WREX provides a decreased gravity environment that allows for significant increased AROM at the shoulder and elbow joints. In addition, WREX allows for the patients to reach away from the body and across midline, improved independence with ADL completion, as well as increased safety in the home and community. WREX may also improve psychosocial wellbeing as all patients demonstrated a positive emotional response to WREX use.

Wilmington Robotic Exoskeleton

Upper-extremity movement is limited in individuals with muscular weakness. This paper describes a novel, articulated upper-extremity orthosis, the Wilmington Robotic Exoskeleton (WREX), which helps people overcome this movement deficit. This prospective, case-controlled study involved an ambulatory patient with arthrogryposis multiplex congenita and 2 nonambulatory patients with spinal muscular atrophy type II. The WREX uses elastic bands to negate the effects of gravity; it allows a person with neuromuscular weakness to move their arm in 3 dimensions. The WREX can be fixed on a brace for ambulatory patients and on the wheelchair for nonambulatory patients. Assessment was performed through motion analysis (with and without the WREX), clinical examination, and qualitative questionnaire. Motion analysis showed a marked improvement in upper-extremity function with the WREX. The questionnaire illustrated enhanced functionality with the WREX including self-feeding, fine motor control, and use of a television remote control. Enhanced functionality resulted in improved quality of life by increasing participation in school, raising self-esteem, and increasing social interaction. Two unexpected outcomes were increased security with trunk inclination and amelioration of the effects of contractures. The WREX provided an increase in functionality and improved the quality of life of the patients. The device has become an integral part of the lives of the 3 patients. Level III in Therapeutic Studies-Investigating the Results of Treatment.

A Randomized Controlled Trial of Gravity-Supported, Computer-Enhanced Arm Exercise for Individuals With Severe Hemiparesis

Background/Objective. The authors previously developed a passive instrumented arm orthosis (Therapy Wilmington Robotic Exoskeleton [T-WREX]) that enables individuals with hemiparesis to exercise the arm by playing computer games in a gravity-supported environment. The purpose of this study was to compare semiautonomous training with T-WREX and conventional semiautonomous exercises that used a tabletop for gravity support. Methods. Twenty-eight chronic stroke survivors with moderate/severe hemiparesis were randomly assigned to experimental (T-WREX) or control (tabletop exercise) treatment. A blinded rater assessed arm movement before and after twenty-four 1-hour treatment sessions and at 6-month follow-up. Subjects also rated subjective treatment preferences after a single-session crossover treatment. Results. All subjects significantly improved ( P ≤ .05) upper extremity motor control (Fugl-Meyer), active reaching range of motion (ROM), and self-reported quality and amount of arm use (Motor Activity Log). Improvements were sustained at 6 months. The T-WREX group maintained gains on the Fugl-Meyer significantly better than controls at 6 months (improvement of 3.6 ± 3.9 vs 1.5 ± 2.7 points, mean ± SD; P = .04). Subjects also reported a preference for T-WREX training. Conclusion . Gravity-supported arm exercise, using the T-WREX or tabletop support, can improve arm movement ability after chronic severe hemiparesis with brief one-on-one assistance from a therapist (approximately 4 minutes per session). The 3-dimensional weight support, instant visual movement feedback, and simple virtual reality software provided by T-WREX were associated with modest sustained gains at 6-month follow-up when compared with the conventional approach.

Effect of a Gravity-Compensating Orthosis on Reaching After Stroke: Evaluation of the Therapy Assistant WREX

Iwamuro BT, Cruz EG, Connelly LL, Fischer HC, Kamper DG. Effect of a gravity-compensating orthosis on reaching after stroke: evaluation of the Therapy Assistant WREX. Objective To evaluate the effectiveness of an upper-extremity orthosis to improve the reaching workspace of stroke survivors. Design Within-subjects repeated-measures design evaluating reaching with and without the Therapy Assistant Wilmington Robotic Exoskeleton (WREX). Setting Laboratory. Participants Stroke survivors (N=10) with chronic upper-extremity hemiparesis. Interventions Not applicable. Main Outcome Measures Arm movement kinematics (Optotrak Certus motion detection system), muscle activity for biceps, triceps, anterior deltoid, and brachioradialis muscles (bipolar surface electromyography). Results Significant improvements of reaching distance occurred for all subjects across all targets ( P<.001) when using the Therapy Assistant WREX. While the self-selected peak speed of hand movement during the reach decreased significantly with the Therapy Assistant WREX ( P<.001), use of the Therapy Assistant WREX led to improved quality of movement as signified by a decrease in jerk ( P<.001) and a shift in the timing of the peak speed to an earlier point in the movement ( P<.001). Electromyographic muscle activity analysis showed that use of the Therapy Assistant WREX led to a reduction in biceps activity across all targets during the reach ( P<.05), in conjunction with a marginally significant reduction in activity of the anterior deltoid ( P<.055). No changes were observed in triceps ( P=.47) or brachioradialis activity ( P=.28). Conclusions By reducing requirements for shoulder activation, the Therapy Assistant WREX improved reaching performance among stroke survivors compared with free reaching, thereby potentially facilitating practice of functional tasks.

Design and Testing of a Functional Arm Orthosis in Patients With Neuromuscular Diseases

The objective of this study was to determine the utility of a passive gravity-balanced arm orthosis, the Wilmington robotic exoskeleton (WREX), for patients with neuromuscular diseases. The WREX, a four-degrees-of-freedom functional orthosis, is energized by rubber bands to eliminate gravity and is attached to the wheelchair. The development and clinical testing of WREX is described in this report. Seventeen patients (14 boys and 3 girls) with muscular disabilities participated in the study. Ages ranged from 4 to 20 years. Criteria for inclusion included a weakened arm, use of a wheelchair, the ability to grasp and release objects, and the ability to provide feedback on device use. Testing consisted of administering the Jebsen test of hand function without WREX and then testing again after approximately two weeks of wearing the WREX orthosis. The timed results of each task within the test then were compared. Specific tasks related to vertical movement required less time to perform with the WREX. A large number of subjects were able to perform the Jebsen tasks with the WREX, where they were unable to perform the task without the WREX. Patients can benefit from WREX because it increases their performance in daily living activities and makes many tasks possible. The range-of-motion in the patients' arms increased considerably, while the time required to complete some of the Jebsen test tasks decreased. Most patients were very receptive to WREX, although a few were ambivalent.

Automating Arm Movement Training Following Severe Stroke: Functional Exercises With Quantitative Feedback in a Gravity-Reduced Environment

An important goal in rehabilitation engineering is to develop technology that allows individuals with severe motor impairment to practice arm movement without continuous supervision from a rehabilitation therapist. This paper describes the development of such a system, called Therapy WREX or ("T-WREX"). The system consists of an orthosis that assists in arm movement across a large workspace, a grip sensor that detects hand grip pressure, and software that simulates functional activities. The arm orthosis is an instrumented, adult-sized version of the Wilmington Robotic Exoskeleton (WREX), which is a five degrees-of-freedom mechanism that passively counterbalances the weight of the arm using elastic bands. After providing a detailed design description of T-WREX, this paper describes two pilot studies of the system's capabilities. The first study demonstrated that individuals with chronic stroke whose arm function is compromised in a normal gravity environment can perform reaching and drawing movements while using T-WREX. The second study demonstrated that exercising the affected arm of five people with chronic stroke with T-WREX over an eight week period improved unassisted movement ability (mean change in Fugl-Meyer score was 5 points +/- 2 SD; mean change in range of motion of reaching was 10%, p < 0.001). These results demonstrate the feasibility of automating upper-extremity rehabilitation therapy for people with severe stroke using passive gravity assistance, a grip sensor, and simple virtual reality software.

Passive exoskeletons for assisting limb movement

This article presents the state of the art in passive devices for enhancing limb movement in people with neuromuscular disabilities. Both upper- and lower-limb projects and devices are described. Special emphasis is placed on a passive functional upper-limb orthosis called the Wilmington Robotic Exoskeleton (WREX). The development and testing of the WREX with children with limited arm strength are described. The exoskeleton has two links and 4 degrees of freedom. It uses linear elastic elements that balance the effects of gravity in three dimensions. The experiences of five children with arthrogryposis who used the WREX are described.