DEMONSTRATIONS

A REHABILITATION R&D DESIGNED LIGHT WAND FOR PERIMETRY & TRAINING
Watson GR, Schuchard RA
Rehab R&D Ctr., Atlanta VAMC, Dept. of Ophthal./Physics, U Missouri - KC

OBJECTIVES: The purpose of this project is to evaluate a new "light wand" for tangent screen perimetry and for training developed at the VA Rehabilitation R&D Center in Atlanta, Georgia.

RESEARCH PLAN: The light wand, an 18-in black rod with a control box/handle on one end and a bright white krypton light on the other, was developed because low vision rehabilitation services are looking for a reliable, accurate, and economical instrument to do macular perimetry for central fields. In the study, standard perimetry tests will be performed with the light wand and the standard reflective wand against a tangent screen, the Humphrey Visual Field Analyzer, and the Scanning Laser Ophthalmoscope.

METHODS: Twenty subjects sixty-five years and older will be recruited with the inclusion criteria of: 1) one or more macular scotomas in an eye with good fixation stability, 2) endurance to provide three hours of reliable data, and 3) accurate refractive corrective lens prescriptions. Perimetry will be performed with all four instruments using standard protocols. The perimetry targets will be set to the brightest each instrument can provide for mapping dense macular scotomas. The characteristics of scotoma location, depth and number will then be compared for each test.

FINDINGS: The light wand will be demonstrated. Findings will be available by the time of the conference.

UPDATE, 5/5/99:
The results of the five perimetry tests were entered into and analyzed with a standard computer statistics package. The location, in degrees from the fixation point, was noted for scotoma(s) found along each of eight evenly spaced radial lines. Also, the absence or presence of discontinuities of scotomas found along each line (either from multiple scotomas or from unusually shaped ones) was noted. Then, the data were compared for all the subjects and for all tests along each radial line. An analysis of variance with repeated measures was used to determine whether there is a significant difference in the results between each instrument and the perimetry protocol.
Using this method of analyzing the data, a relationship between the reflective wand and the light wand results was shown, as well as an expected close results between the SLO low- and high-power laser results. However, the investigators feel that a more detailed grid or shape analysis of the data needs to be done to accurately discern which of the light wand, reflective wand, and Humphrey tests compare best with the SLO (the "gold standard"), and to what degree.

CLINICAL RELEVANCE: This project will continue to develop the light wand into a reliable, accurate, and cost-effective instrument for macular perimetry and eccentric viewing training in vision rehabilitation services.

Core-funded project by the Rehab R&D Center, Atlanta, GAD19

EXERCISE EXPERT SYSTEM FOR OLDER ADULTS
Boyette, LW, Manuel, S, Lloyd, A, & Grasch, D, Wyse, E
Rehab R&D Ctr, Atlanta VAMC

OBJECTIVES: This study developed a computerized exercise expert system (EES) that can be used to encourage older adults toward a lifestyle of physical activity by customizing individual exercise plans. The EES focuses on determinants that act as incentives/barriers to exercise and uses recommended strategies for improving exercise initiation/adherence for older adults.

RESEARCH PLAN: First, a literature review containing all factors related to initiation/adherence of exercise was conducted. A diagnostic questionnaire obtaining information on exercise habits and preferences was then created. Strategies to optimize exercise initiation/adherence were compiled. A Practitioner's Report, Client's Report, Exercise Knowledge Sheet, and Exercise Plan were produced based on responses to the questionnaire.

METHODS: Using a repetitive process, all aspects of the EES were reviewed, critiqued, & validated by local/national experts in health related fields. Case studies of older adults were analyzed and used to refine the EES. The analyses focused on examination of the exercise plans created by the EES in response to each case study's profile.

FINDINGS: The EES has been updated to reflect the experts' opinion of the diagnostic questionnaire, Practitioner's Report, and the recommended strategies. Over 30 case studies have been cross examined to find discrepancies between the EES and expert opinion until consensus was reached concerning the appropriateness of each developed exercise plan.

CLINICAL RELEVANCE: The EES will help facilitate the health practitioner's knowledge and efficiency in providing a crucial aspect of primary care and disease prevention through exercise. The expert system can later be expanded to include recommendations specific to subgroups of frail, diseased, and disabled elderly individuals.

VA Rehabilitation Research & Development Service

A SCANNING LASER OPHTHALMOSCOPE LOW VISION REHABILITATION SYSTEM (SLO LVRS)
Schuchard RA, Maino J, Lin WT, Timberlake G, Fletcher D, Nygaard R, Young J, Ceron O
Kansas City VAMC, Univ of Missouri-KC, Univ of Kansas

OBJECTIVE: To develop an effective, efficient, easy to use low vision rehabilitation system that can be used for low vision diagnosis and training.

RESEARCH PLAN: Research results have shown that scotoma mapping and PRL (preferred retinal locus) evaluation in low vision people is more accurate with an SLO (scanning laser ophthalmoscope). However, there was no software available that met the needs of visual rehabilitation clinicians or researchers.

METHODS: The software was developed using Visual C with Microsoft Foundation Classes. Currently the software is compiled to run on a Pentium processor CPU with 32 M RAM and Windows NT operating system. The graphics/imaging interface between the SLO and the computer is a TARGA 2000 Pro imaging card from TrueVision Inc. This board allows real time image acquisition and state-of-the-art graphics output capability. The diagnostic software allows macular perimetry testing (with hybrid, kinetic, and static protocols), acuity testing (with Snellen letters, words, and Landolt C targets), preferred retinal locus testing (fixation, saccade, and pursuit), and reading testing. The training software has incorporated standard eccentric viewing training techniques.

FINDINGS: The SLO LVRS has been successfully "beta" tested in two low vision clinical services (VA VICTORS Program and a private practice) and a VA Rehabilitation Research & Development Center.

CLINICAL RELEVANCE: The existence of macular scotomas degrade visual performance and the ability to use a PRL is the best predictor of success in regaining an independent and full lifestyle. The SLO LVRS provides the low vision clinician with an effective, efficient, and easy to use visual rehabilitation system to diagnose and train low vision people.

(Rehabilitation Research & Development Program)

WHEN IS 20/40 NOT 20/40? A DEMONSTRATION OF THE EFFECTS OF RING SCOTOMA ON VARIOUS ACTIVITIES OF LIVING
Maino JH¹; Young J²; Schuchard RA³; Timberlake GT⁴
Optometrist & Chief, VICTORS¹, Regional Low Vision Rehabilitation Center, Kansas City VA Medical Center, Kansas City, Missouri; Cl. Professor¹, Department of Ophthalmology, University of Kansas Medical School, Kansas City, Kansas, Occupational Therapist & Research Associate², Eye/VICTORS Regional Low Vision Rehabilitation Center, Kansas City VA Medical Center, Kansas City, Missouri, Associate Professor³, Department of Ophthalmology, University of Missouri Medical School, Kansas City, Missouri, Professor⁴, Department of Ophthalmology, University of Kansas Medical School, Kansas City, Kansas

OBJECTIVES: The objective is to show how visually impaired patients with good vision (20/40) and a ring scotoma can still exhibit substantial problems with activities of living.

DEMONSTRATION PLAN/METHODS: The functional impact of doughnut hole vision secondary to ring scotoma is demonstrated through the use of video and poster information. A doughnut hole vision/ring scotoma simulator is used to provide participants a personal appreciation of the functional problems associated with this disorder.

FINDINGS: Patients with doughnut hole vision secondary to ring scotoma may present with near normal visual acuity and normal peripheral vision, yet function as though they were legally blind. These patients find reading, identifying faces, driving and other activities of living very difficult or impossible to perform.

CLINICAL REVELANCE: Doughnut hole vision secondary to ring scotoma occurs when an ocular disease such as geographic age related macular degeneration creates a small area of near normal central retina surrounded by a ring of abnormal retina which is then surrounded by near normal peripheral retina. Visually, such a patient may exhibit 20/40 visual acuity while functioning at the legal blindness (20/200) level. These patients typically require higher levels of magnification than that predicted from their visual acuity in order to read or perform other activities of living. Clinicians should suspect doughnut hole vision/ring scotoma when visual acuity and visual ability do not correspond.

This research is supported by the Department of Veterans Affairs Research Rehabilitation and Development Grant # C838-2RA

QUANTIFYING SPOKEN LANGUAGE HANDICAP IN APHASIA
Patrick J. Doyle, Ph.D. and Malcolm R. McNeil, Ph.D.
Aphasia Rehabilitation Research Laboratory and Clinic VA Pittsburgh Healthcare System, Pittsburgh PA

Current procedures for the assessment, description, and quantification of aphasic language impairment fail to assess either directly or indirectly, the impact of the disordered language on the communicative partner's reception of the message. Because of the lack of attention to the consequences of aphasic individuals' impaired language, in the face of well quantified and elegantly described aphasic performance, the functional impact of the impairment has gone practically undescribed and unquantified. One solution to this problem is to assess the relative effort expended by the listener while processing and comprehending spoken language. A general measure of the effort expended, if shown to be differentially sensitive to varying severity levels, and types of aphasic impairment, would provide a composite measure of all the physical, social, psychological, linguistic and communicative skills, weakness and biases of the listener.

As such, our laboratory has developed and will demonstrate a computer-based interactive assessment tool designed to objectively quantify the degree of spoken language handicap resulting from different types and frequencies of aphasic language errors as they occur in connected speech. Using resource allocation theory (Hirst & Kalmer, 1987; Kalmeman & Treisman, 1984; McNeil, Odell and Tseng, 1991), as the guiding theoretical model, our laboratory developed a dual-task software program for standard lap-top computers that requires participants (i.e., normal listeners) to simultaneously perform a visuo-motor tracking task (i.e., the primary task), while listening to the connected speech of persons with aphasia, (i.e., the secondary task). At the completion of the dual task, listeners are required to provide information regarding the content of the aphasic discourse. In this dual-task paradigm, effort is quantified by performance on the visuo-motor task, and information transfer is quantified by performance on the listening task. We propose to demonstrate that the effort expended for the primary task as assessed by the dual-task paradigm, will vary greatly by listener. That is, depending on the state of the listener, differential amounts of cognitive resources (effort) will be expended in the processing and comprehending the impaired language. Further, we propose to demonstrate a systematic increase in effort expenditure within listeners from the comprehension of non-impaired spoken language to the processing and comprehension of spoken language produced by patients with different severity levels and types of aphasic impairment. This measure, when combined with the measure of information transfer will provide an important metric of the spoken language handicap shared by the disordered speaker and any given listener.

Visitors to this demonstration will have the opportunity to participate in the dual task while listening to both experimentally created, and authentic aphasic discourse.

DEVELOPMENT OF POWERED PROSTHETIC LOWER LIMB
Klute GK, Czerniecki J, and Hannaford B
Rehab R&D Ctr, VA Seattle; University of Washington Elec Engineering

OBJECTIVE: Improve below-knee amputee gait by determining the ability of a powered prosthetic limb with muscle-like actuators to provide the missing propulsive force of the ankle musculature.

RESEARCH PLAN: Develop actuators with muscle-like performance and incorporate them into a below-knee prosthetic limb. Once fabricated, we plan to test the hypotheses that such a device will: (1) Reduce the metabolic costs of locomotion, (2) Improve gait symmetry, and (3) Reduce the perceived level of effort of amputee gait.

METHODS: Use non-linear finite element methods and computer models incorporating fluid flow effects to develop lightweight, energy efficient actuators whose force-length-velocity characteristics mimic that of the Hill muscle model.

FINDINGS: Eccentric and concentric test results for our current McKibben actuators reveal force-length characteristics similar to biological muscle. We seek to improve the velocity dependent characteristics by adding additional damping. Our computer models have led to specification of a miniature hydraulic damper whose force-velocity relationship is controlled by flow restricting orifices. Our work in progress includes fabricating and testing these new actuators.

CLINICAL RELEVANCE: Many prosthetic users exhibit lack of endurance, non-symmetrical gait, and high levels of effort while walking at self-selected rates. A powered lower limb prosthesis may provide measurable gains in performance observable in clinical practice. The end result is patients who can walk farther, faster, and with less effort when compared to conventional prosthetic devices.

This research was supported in part by Department of Veterans Affairs Center Grant A0806-C.

MULTIMEDIA AMPUTEE REHABILITATION TEAM TRAINING
Boone DA, Laing LS, Coleman KL, Burgess EM, Smith DG, Mathews DE
PRS; Seattle RR&D Ctr; Ortho and Rehab Depts., Univ. of Washington, POF

OBJECTIVES: The objective of this development initiative has been to create and produce educational materials for amputee clinic team training and improvement.

RESEARCH PLAN: Text, photo and film materials produced for the VA by Dr. Burgess have been digitally scanned and edited. A user interface was developed with consistent navigation and control methods for the various media types. A database hidden from the user maintains cross referencing links between the media.

METHODS: Multimedia computer based presentations represent amputee specific patient care situations to the user. An interactive interface allows the user to seek out specific information regarding amputee management or to easily explore the topic freely. Digitized video and photos are integrated with cross referenced text.

FINDINGS: This development effort has produced 2 multimedia CD-ROM disks specific to rehabilitation management of amputees. This first teaches clinical gait analysis and prosthetic alignment for the transfemoral amputee. The second disk focuses on surgical and early post-operative management of amputees for physical therapists and prosthetists.

CLINICAL RELEVANCE: Continuing education and development of patient management teams is an essential part of maintaining a high standard of clinical care in the VA. Easily disseminated materials, rich in practical content are beneficial to this ongoing process.

(Funded by VARR&D and private donations.)

STEP ACTIVITY MONITOR: A TOOL FOR FUNCTIONAL EVALUATION AND ASSESSMENT OF REHABILITATION OUTCOME
Coleman KC, Boone DA, Smith DG
Prosthetics Research Study, Seattle, WA

OBJECTIVES: The objective of this project was to develop a clinically viable instrument to provide relevant measurements of physical function for evaluating outcome and guiding treatment decisions.

RESEARCH PLAN: The clinical and engineering resources at PRS were used to develop an affordable instrument that provides clinically relevant measurements of ambulatory function. The monitor was required to be unobtrusive, highly accurate, and able to withstand the environment challenges of long-term, real-world monitoring.

METHODS: The Step Activity Monitor (SAM) is used to obtain minute-by-minute records of the number of steps a person takes for up to one month. The sensitivity of the monitor is programmed for the gait style of each subject. After monitoring, the data are downloaded to a computer for long-term storage and analysis. Patterns of ambulation (including levels and intensity of activity and time of rest) are quantified.

FINDINGS: The SAM has proven durable for long-term use. Rigorous testing across multiple studies has found the accuracy to exceed 99.4%. The following studies have been completed: 1) Activity profiling of persons with diabetes and peripheral neuropathy. 2) Comparison of high-end (FlexWalk II) and low-end (SACH) prosthetic feet. 3) Assessment of total hip replacement outcome.

CLINICAL RELEVANCE: Objective, quantitative measures of function are increasingly required for the evaluation, justification, and guidance of treatment in many fields of medicine and rehabilitation. The SAM provides a clinically viable method for obtaining measures that reflect the level of function patients ACTUALLY manifest throughout their daily lives. Because inactivity is known to be a major risk factor for many serious physical and psychological illnesses, long-term step monitoring is an extremely relevant and valuable means of evaluating outcome with respect to both short-term and long-term considerations.

Development was funded by the Department of Veterans Affairs, Rehabilitation Research and Development Service, the University of Washington Department of Orthopaedics, and the Prosthetics Outreach Foundation.

OVERVIEW OF THE VA PEDORTHIC COMPUTER-AIDED DESIGN & COMPUTER-AIDED MANUFACTURING SYSTEM
Houston, V.L.^1,2; Mason, C.P.¹; Luo, G.^1,2; LaBlanc, K.P.¹; Garbarini, M.A.^1,2; Beattie, A.C.^1,2; Mussman, M.³; Cruise, C.M.^1,2;
¹Dept. Veterans Affairs Med. Ctr. New York; ²New York Univ. Med. Ctr.; ³New York Podiatric College of Med.

OBJECTIVE: Development of a computer-aided design and manufacturing (CAD/CAM) system for effective and efficient production of well-fitting, functional, and comfortable custom orthopedic footwear for US Veterans.

RESEARCH PLAN: (a) Sample and analyze the medical/podiatric/pedorthic records of a representative number of VAMC pedorthic patients to identify and quantify VAMC New York National Footwear Center (NFC) requirements. (b) Develop an intuitive, user-friendly, clinically effective and efficient pedorthic CAD/CAM system fulfilling NFC requirements. (c) Conduct limited clinical tests with the pedorthic CAD/CAM system.

METHODS: The medical/podiatric/pedorthic records (including footwear lasts and patterns) of 289 VAMC pedorthic patients were sampled and used to establish specifications for a pedorthic CAD/CAM system. A prototype system was developed meeting NFC specifications for orthopedic footwear last, insole, and upper pattern design and manufacture. Laboratory and clinical tests were performed to determine the system features that were successfully implemented and those areas needing further refinement.

FINDINGS: The Pedorthic CAD System was installed in the NY VAMC NFC for clinical testing. A range of footwear from extra depth, plain toe, low quarter Blucher style shoes with soft custom insoles to high top orthopedic boots have been successfully designed and manufactured in trails with four control subjects and twelve VAMC NFC pedorthic patients.

CLINICAL RELEVANCE: For many patients with neuromusculoskeletal injuries, pathologies, and biomechanical disorders, of their feet and ankles, timely provision of well-fitting, functional, comfortable custom orthopedic footwear is essential for successful rehabilitative treatment and care. It can mean the difference between normal mobility and independence, and confinement in a wheelchair or even lower limb amputation.

Sponsor. VA Rehabilitation Research & Development Service

VA-CYBERWARE PROSTHETICS-ORTHOTICS OPTICAL LASER DIGITIZERS
Houston, V.L.^1,2; Mason, C.P.¹; Beattie, A.C.^1,2; LaBlanc, K.P.¹; Luo, G.^1,2; Garbarini, M.A.^1,2; Cruise, C.M.^1,2;
¹Dept. Veterans Affairs Med. Ctr. New York; ²New York Univ. Med. Ctr.

OBJECTIVE: To develop optical digitizers capable of accurate, repeatable, consistent, and expeditious characterization of amputees' residual limb and orthotics patients' torso and limb segment spatial geometry and surface topography.

RESEARCH PLAN: (a) Refine and enhance design specifications for, and procure and test new, second generation prosthetics-orthotics optical digitizers. (b) Perform clinical application studies to establish the level of temporal efficiency, intra-prosthetist repeatability, and inter-prosthetist consistency the digitizers afford in measurement of amputees' residual limb spatial geometry and surface topography, in comparison with current computer-aided (CAD) plaster wrap cast/electromechanical digitization procedures.

METHODS: Refined and enhanced design specifications for second generation torso-limb and genu-tibial optical digitizers were developed. Prototypes have been constructed, calibrated, and laboratory tested. Clinical tests with the torso-limb digitizer are being conducted at the NY VAMC, and the genu-tibial optical digitizer is being field tested at five VAMC AFMA Centers.

FINDINGS: Tests of the digitizers to date indicate the principal deficits identified in the first generation prototypes have been corrected. Initial clinical test results show the digitizers to be more accurate, efficient, repeatable and consistent than conventional or current CAD plaster wrap cast techniques.

CLINICAL RELEVANCE: Development of equipment to accurately, efficiently, repeatably, and consistently measure amputee residual limb and orthotics patient torso and limb segment spatial geometry and surface topography will enable design and manufacture of better fitting, more comfortable, and more functional prostheses and orthoses, than those produced using conventional, or current CAD, iterative trial-and-error method. This will also reduce prosthesis and orthosis temporal and fiscal provision costs.

Sponsor. VA Rehabilitation Research & Development Service

REMEDIATION OF COGNITIVE IMPAIRMENTS IN SCHIZOPHRENIA THROUGH COMPUTER-BASED COGNITIVE RETRAINING: A DEMONSTRATION
Gill PG, VA Connecticut HCS; Bell MD, VA Connecticut HCS & Yale University School of Medicine

OBJECTIVE: To demonstrate computer-based attention, verbal memory, and executive function retraining and an audio-based dichotic listening task for remediating cognitive deficits in people with schizophrenia.

RESEARCH PLAN: Attendees will experience how patients with schizophrenia or schizoaffective disorder receive cognitive retraining by performing five computer-based tasks on a computer display and by performing a dichotic listening task on a audio display.

METHODS: Five tasks from the PSSCogReHab software package (Bracy, 1995) have been modified for the purpose of having them administered as a series of difficulty-graded attention, verbal memory and executive function tasks. The first two tasks provide training in visual attention where the trainee is required to respond to a series of targets while visually tracking a moving object. The next two tasks provide training in verbal memory where one task requires the trainee to recall a sequence of digits and the other requires the trainee to indicate the numerical position of a word that was presented in a list. The final task is similar to the Tower of Hanoi and provides training in executive skills. The dichotic listening task provides training in auditory attention in which the trainee is required to pay attention to a story heard in the right ear while a poem is being presented in the left ear.

CLINICAL RELEVANCE: It is the goal of this demonstration to disseminate information regarding computer-based cognitive retraining as part of rehabilitation services provided to schizophrenic patients.

A WEARABLE CONTROLLER FOR CLINICAL STUDIES INVOLVING MULTI-IMPLANT FNS SYSTEMS
J. Buckett, R. Triolo, D. Ferencz, M. Katorgi, C. Bieri, J. Weisgarber, T. Vrabec, D. Johnson
Case Western Reserve University; VA Center of Excellence in FES, Cleveland OH

OBJECTIVE: To design, test and produce a clinically deployable external control unit (ECU) capable of simultaneously controlling multiple implanted neuromuscular stimulators.

RESEARCH PLAN: Implantable functional neuromuscular stimulation (FNS) systems can provide proximal arm control or bimanual grasp to persons with tetraplegia, and standing and enhanced mobility to individuals with paraplegia. Clinical application of such advanced systems has been limited by the number of stimulus channels (typically eight) available per implant and the inability to control more than one implant at a time. The design of the new ECU was undertaken to coordinate the actions of two implanted stimulators.

METHODS: The ECU transmits power and control information through two external coils over inductive links to two implanted stimulators. Consumer input solicited from clinicians and current FNS users was integrated into a set of functional requirements describing the physical characteristics and operation of the device. Functional specifications were derived from the clinical requirements to provide initial detail on the technical design. Specifications led to a full-scale physical prototype, which was reviewed by the clinicians and potential users to insure suitability for clinical use. The hardware is based upon a central microcontroller; programming is accomplished with a PC via a standard serial interface.

CLINICAL RELEVANCE: The physical design and operating characteristics were acceptable for use outside of the laboratory. The design and development process yielded a compact, externally programmable device with a self-contained power supply that is completely wearable and rugged enough for daily use. Complete design documentation is sufficiently detailed for assembly and testing by an outside contractor, allowing for the large-scale production required for multi-center clinical trials.

(This work funded by VA Merit Reviews B681 & B83)

A MULTICHANNEL IMPLANTABLE SYSTEM FOR NEURAL CONTROL
J. Buckett, R. Brock, K. Kilgore, F. Montague, P. H. Peckham
Cleveland VA FES Center of Excellence and Case Western Reserve University

OBJECTIVES: A neuroprothesis, composed of an implanted stimulator-telemeter device, multiple implanted stimulating electrodes, an implanted joint angle sensor, and an external power and control unit, has been developed to restore function in the hand and arm of individuals who have sustained cervical spinal cord injury.

RESEARCH PLAN: The neuroprosthetic system restores hand grasp and release function through a command derived from wrist position for a 'powered' tenodesis similar to a flexor driven hinge splint. As the user flexes her/his wrist, the stimulus levels to the finger flexors are increased.

METHODS: The implanted components of the system consist of the implantable stimulator-telemeter device (IST), the ten stimulating electrodes, and the implantable joint angle transducer (IJAT). In-line connectors are used to connect the electrodes and IJAT to the IST. The external portions of the system consist of the external control unit (ECU) and the external coil. The ECU provides power and control to the implanted IST and recovers data and status from the IST through the external coil.

FINDINGS: At present the IST device has been implanted in four individuals. Two individuals have also been implanted with the IJAT. All four individuals use their systems on a regular basis at home and in the workplace.

CLINICAL RELEVANCE; Restoration of lost function increases the individual's independence thus decreasing their reliance on assistance in both the home and workplace. This independence also increases the viable employment opportunities easing the reliance on other forms of financial support.

(This work has been supported by the Department of Veterans Affairs Medical Center Rehabilitation Research and Development Service and the NIH grant number NS29549)

COMPLIANCE MONITOR TO MEASURE PATIENT WEARING-TIME FOR SPINAL ORTHOSES
Havey RM, Gavin TM, Patwardhan AG RR&D Ctr, VA Hines, Dept. of Orthopaedic Surgery, Loyola Univ. Medical Center, Maywood, IL, BioConcepts, Inc. Orthotic-Prosthetic Center, Burr Ridge, IL

OBJECTIVES: Development and testing of an orthosis wearing compliance monitor that will accurately and reliably measure patient wearing time of a spinal orthosis.

RESEARCH PLAN: (i) Refinement of the data recorder and software. (ii) Testing on plaster casts to determine effects of exposure to climate changes. (iii) Validation of monitor to make accurate and reliable measurements using ten volunteer subjects for one-week. (iv) Evaluate long-term exposure to activities of daily living on the durability and accuracy of the compliance monitor on twenty consenting patients for three months.

METHODS: Force Sensors placed in four areas of spinal orthoses collected data to a recording device concealed within the walls of spinal orthoses. Spinal orthoses with monitors were donned on plaster casts and were periodically removed. All time that the orthoses were on or off the cast was recorded manually in a log and was compared to wearing time data recovered from the recorder. During testing on ten volunteer subjects, wearing time was manually recorded and was compared to wearing time data recovered from the recorder.

FINDINGS: At least three of four sensors triggered when the orthoses were worn, and when removed, all sensors switched off. Preliminary work demonstrates that it is possible to accurately and reliably measure wearing-time.

CLINICAL/RELEVANCE: No objective method to measure compliance with orthosis wear exists. This device allows quantitative compliance measurement. Non-compliance with prescribed wearing hours is postulated to be a cause of treatment failure. This monitor is also adaptable to all orthoses and prostheses.

Acknowledgment: Funded by grant (A865-RC) from the Rehabilitation Research and Development Program, Department of Veterans Affairs.

LUMBAR SPINE STABILITY UNDER IN VIVO LOAD LEVELS
Patwardhan AG, Havey RM, Meade KP, Lee B, Dunlap B
VA Hospital, Hines, IL

OBJECTIVES: This experiment demonstrates the response of a synthetic lumbar spine to a compressive follower load of in vivo magnitude.

RESEARCH PLAN: Lumbar spine compression reaches over 1000N during standing and lifting. Ex vivo experiments demonstrate the lumbar spine, without muscles, collapses under a vertical load of 80-100N. We demonstrate in a synthetic lumbar spine that the load carrying capacity increases if the internal compressive load follows the tangent of the curve through the centers of rotation of the lumbar segments.

METHODS: A biofidelic synthetic spine has been fabricated to demonstrate the increase in spinal stability when subjected to a "follower load" whose path approximates the tangent to the spine. Our experimental apparatus applies physiologic loads up to 1200N to the synthetic lumbar spine using cables attached to L1 and passed through adjustable guides attached to L2- sacrum.

FINDINGS: The synthetic spine collapsed at a vertical load of 100N while a 1200N follower load caused negligible changes in spinal curvature in the sagittal and frontal planes.

CLINICAL RELEVANCE: The follower load concept allows pre-clinical testing of spinal implants under realistic in vivo loading conditions. The findings also support the hypothesis that deep muscles co-activate to generate a follower load path and stabilize the lumbar spine under physiologic compressive loads.

(Funded in part by VA RR&D Grant A830-RA.)

THE ADVANCE COMMODE-SHOWER CHAIR FOR SCI VETERANS
Malassigne, P, Research Service, Clement J. Zablocki VAMC, Milwaukee Professor, Industrial Design, Milwaukee Institute of Art & Design. Nelson, A L., RN, Ph.D., Associate Chief Nursing Service for Research, James. A. Haley VA Hospital, Tampa. Cors, M W, Dept. of Physical Med. & Rehab., Medical College of Wisconsin.

OBJECTIVES: Design a safe and effective chair for SCI veterans and caregivers.

RESEARCH PLAN: Before redesign, an evaluation of existing chairs with patients and caregivers was undertaken. Functional criteria for the new chair were established from the findings.

METHODS: An iterative process of design, prototype fabrication and evaluation at two VAMC SCI centers was used to design the new chair.

FINDINGS: During the development process, several new features were invented. Footlift: designed to assist users with washing their legs and feet. To use, the footlift is set horizontally and the user puts his feet into the heelcup. Seat: designed with a central opening and cut-outs on three sides for hand access, it incorporates extensions projecting to the front corners to facilitate transfers. Pivoting armrests: designed with a lockable lever mechanism for their release, the armrests swing back out of the way for transfer. Contoured footrests: designed to protect the feet with their rounded form, the drainable footrests incorporate a non-slip surface. Height adjustment with a lever handle. Oversized handrings: with a unique (38 mm - 1.50 in) diameter among wheelchairs, these rubber coated handrings increase surface area for the hand.

CLINICAL RELEVANCE: There are over 200,000 persons with SCI in the US requiring bowel care an average of three times a week. The AdVAnce commode-shower chair will significantly impact on the user's quality of life, safety, prevent falls and pressure ulcers. At the same time it will improve efficiency of caregivers who perform bowel care procedures.

Funding: DVA, Rehabilitation R&D Service

GUIDING PROGRESS IN UPPER EXTREMITY HEMIPLEGIA DURING ROBOT-AIDED THERAPY
Shor P, Burgar CG, Lum PS, Van der Loos HFM
Rehab R&D Center, VA Palo Alto, Department of Functional Restoration, Stanford University

OBJECTIVE: To determine effective methods for guiding progress in upper extremity motor function in chronic stroke subjects with robotics assistance.

RESEARCH PLAN: Clinical testing to determine therapeutic benefits of robot-aided therapy as an adjunct to traditional therapy.

METHOD: Movements of the shoulder and elbow are primarily addressed. Neurodevelopmental treatment is applied as subjects perform unilateral and bilateral passive and active movements. Parameters of the robot's movements are programmed based on individual's joint range of motion (ROM) measurements defining start point for therapy. Prior to robot attachment, ten minutes of joint mobilization, tone inhibiting techniques, and passive/active ROM is given. An emergency stop is easily accessible by both subject and operator; a breakaway mechanism helps maintain a position that is functional and safe. Both verbal and physical cues facilitate desirable movements. The subject may also be taken out of the robot as needed should the subject require further facilitation.

FINDINGS: Subjects would occasionally experience discomfort while executing movements, and observed were increased synergistic patterns and tonality in the upper extremity during/after treatment; modifications were provided accordingly (i.e. positioning, gradation of tasks). Possible contributing factors include overestimation of subject capabilities, changes in physical health or medication, a break in daily routine, level of motivation, limitations of neurodevelopmental treatment applications and the environment.

CLINICAL RELEVANCE: If robotics is to be used in therapy, given the variability of neurological states (i.e. tone and pain levels), thorough attempts should be made to ensure safety, and to preserve the integrity of the affected extremity while facilitating improvements in motor function performance.

Funding VA RR&D Merit Review - #B96-1052R

DUAL-AGENT USER INTERFACE FOR AN ASSISTIVE ROBOT
Wagner JJ, M.S.M.E.(**), Van der Loos HFM, Ph.D.(*), Burgar CG, M.D. (*), Leifer LJ, Ph.D.(**)
*Rehabilitation R&D Center, Palo Alto VA Health Care System, Palo Alto, CA **Design Division, Department of Mechanical Engineering, Stanford University

OBJECTIVES: We are designing a novel user interface for an assistive robot. The ProVAR desktop personal robot is for use in the clinic by therapists and their clients with high-level spinal cord injury for communication and manipulation tasks.

RESEARCH PLAN: To allow a user to access ProVAR's complex force control and sensor capabilities, which collectively provide robust operation of tasks such as inserting videotapes and manipulating printer output, an interface must allow easy task building and execution. The interface embodies a unique "dual-agent" concept to communicate with the user, capitalizing on new theories of people' social responses to computer technology.

METHODS: While the ProVAR architecture is complex, to the user it is divided into two distinct, social entities: Pinocchio is simple-minded, with limited communication ability; Jiminey is smart, helping the user to get Pinocchio to do tasks. With two characters, we hypothesize that users have a greater tolerance for complex commands and errors. By siding with the user, Jiminey becomes a team member, while blame for mistakes gets shifted from the user onto Pinocchio and credit gets shifted to the user.

FINDINGS: The interface is currently being implemented as part of the overall ongoing ProVAR project. Evaluations of interface prototypes are being coordinated with the VA Palo Alto Spinal Cord Injury Center.

CLINICAL RELEVANCE: For persons with high level spinal cord injury to have functional control over activities of daily living through the use of complex technology, interfaces must enable the functionality while hiding the complexity.

[This work is being funded by the VA Rehabilitation R&D Service through Grant B899-2DA.]

DEMONSTRATION OF WEARABLE ACCELEROMETRIC MOTION ANALYSIS
Sabelman, EE; Troy, BS; Kenney, D; Gabrielli, S; Yap, R; Jaffe, DJ; Nakahara, A; Winograd, CH
Rehab R&D Ctr & GRECC, VA Palo Alto HCS; Functional Restoration Dept., Stanford Univ.

OBJECTIVES: We are developing a wearable accelerometric instrument ("WAMAS") to measure human movement patterns that contribute to falls in the elderly. This demonstration will show the instrument's capabilities for unrestrained movement monitoring and audible feedback.

RESEARCH PLAN: Technological progress since the first generation WAMAS permits construction of a more capable system, as needed for entry of accelerometry into routine clinical use. Our current design/development project to incorporate new technology is planned to culminate in a Co-operative R&D Agreement (CRADA) with a commercial partner.

METHODS: Three-axis silicon accelerometers are attached on eyeglass frames to monitor head motion, on a belt near the body's center of mass, or elsewhere on the body. Data are sampled up to 112 times per second by a wearable computer commanded by remote control.

FINDINGS: Volunteers perform walking and standing tasks of varying difficulty, including standing on an unstable platform. Their head and waist motions will be compared to values obtained previously for subjects of similar age and gender. Also to be demonstrated are speech output and self-leveling functions.

CLINICAL RELEVANCE: The WAMAS occupies a niche in the spectrum of tools for diagnosis of movement disorders midway between qualitative estimation of risk of falling and expensive laboratory-based gait analysis. The WAMAS can act as a surrogate therapist, monitoring a patient's progress and compliance with a course of therapy. It is often difficult to document small functional changes in balance and gait; the WAMAS can provide such information in home and out-patient settings.

ACKNOWLEDGEMENTS: VA RR&D pilot project E972-PA, Merit Review projects E601-RA, -2RA, -3RA, design/development project E2182-DA; Maven Technologies donation to PAIRE; PAIRE "flex-fund" grants for student support; former staff: J. Martino, D. Chesney, J. Gadd, P. Merritt, C. Morris; ; summer students: M. Liu, J. Lin, C. Washington.

ADVANCES IN SURFACE ELECTROMYOGRAPHY TECHNOLOGY
De Luca CJ, Roy SH, Gilmore LD
Research Services Boston VA Medical Center and the NeuroMuscular Research Center, Boston University, Boston, MA

OBJECTIVES: The demonstration will present technological advances in the detection and analysis of the Electromyographic (EMG) signal which is generated when a muscle contracts. The purpose of the demonstration is to show user-friendly improvements made in EMG devices that render the application of surface EMG more convenient and reliable. The new technology eliminates the tediousness and akward nature of previously available EMG devices.

DESCRIPTION: Four aspects of the technology will be presented: 1) A new series of electrodes, 2) a new skin-electrode interface, 3) new EMG systems, and 4) new EMG analysis software. 1) The electrodes- We have developed small (40 mm x 20 mm), low-profile (5 mm), revolutionary parallell-bar electrodes with unparalleled signal fidelity. They contain preamplification and specialized circuitry in the electrode casing. This electrode requires no gel, no skin preparation and can be located on top of the skin hairs. It is available in three versions: a) the standard one described above; b) a version, which, in the same case, contains band-pass filters and a gain of 1000; c) a version, which in the same case, contains a double-differential configuration useful for eliminating cross-talk. 2) The skin electrode interface- A thin plastic strip, with adhesive on both sides, which allows the detection bars of the electrode to make contact with the skin. It is designed to withstand excessive movements of the skin. These interfaces have successfully held the electrodes in good electrical contact throughout a four and one half hour marathon and 2 soccer games. 3) We have developed three EMG devices which use the new electrode technology; a 2 channel, a 4 channel, and an 8 channel system. The two channel system is powered by a 9 V battery, is light weight and may be worn on the body. All the systems may be interfaced with a computer. 4) The Software allows for real-time monitoring of up to 16 channels of EMG signals. Any one channel may be processed and monitored in real time by its rms or mean average value. Additionally, the power density spectrum and the median frequency of any one channel may be monitored in real time. All these variables are presented on one screen simultaneously. Post processing allows for calculation of a wide variety of variables. The package also contains a tutorial on the correct use and processing of the EMG signal. It provides "Caution" indications when incorrect operations are attempted.

CLINICAL RELEVANCE: The use of EMG signal is widely applied for monitoring the performance of muscles in rehabilitation environments. Our new technology provides safety, convenience and reliability beyond that found in other devices on the market. These features reduce the amount of time (and cost) required for using the technology, as well as increase the inclination of clinicians to objectively monitor directly the performance of muscles.

(Supported by the Rehabilitation Research and Development Service of the Veteran Affairs and Liberty Mutual Insurance Company)

DEVICES FOR THE ASSESSMENT OF HUMAN PERFORMANCE
De Luca CJ, Roy SH, Oddsson L, Jabre J
Research Services Boston VA Medical Center and the NeuroMuscular Research Center, Boston University, Boston, MA

OBJECTIVES: The proposed demonstration will provide an opportunity for the public to view two promising assessment procedures, the Back Analysis System (BAS) and the Stability Analysis System (SAS). The devices focus on two of the most common musculoskeletal conditions necessitating rehabilitative care within and outside of the VA patient care services: lower back pain injury and falls. The approaches adopted by the innovations presented in this demonstration provide clinically validated methods through beta site testing.

DESCRIPTION: The following descriptions summarize the features of these devices:

The Back Analysis System: This device assesses electromyographic activity from six lumbar back muscles during a fatiguing isometric trunk extension contraction. The collected EMG data is processed and a classification score that indicates the performance of the back muscles is compared to normative behavior. Protocols have been developed to distinguish individuals with low back pain and to evaluate the degree of impairment in the low back muscles.

The Stability Analysis System (SAS): This device acquires center of pressure signals during quiet stance and implements methods from statistical mechanics to extract parameters that reflect the behavior of the postural control system. A stabillogram-diffusion analysis processes the center of pressure signal as a random walk. The information is used to distinguish individuals with balance problems and to evaluate the degree of disability in their postural stability.

CLINICAL RELEVANCE: The urgent need for cost-containment and evidence-based practice has resulted in renewed efforts to streamline the delivery of rehabilitation services through the use of objective and quantitative assessment approaches. The devices presented in this demonstration are needed in research and clinical practice to objectively measure human performance and identify impairments of the neuromuscular system.

(Supported by the Rehabilitation Research and Development Service of Veterans Affairs and the Liberty Mutual Insurance Company)

DEVELOPMENT OF A COMPUTER MODEL OF MOBILITY COVERAGE FOR THE VISUALLY IMPAIRED
Blasch BB, De l'Aune, WR
Rehab R&D Ctr, VA Atlanta

OBJECTIVES: The objective of this pilot study was to develop a computer program capable of graphically representing cane coverage in mobility of individuals with severe visual impairment.

RESEARCH PLAN: The procedure was to identify the critical elements of a person using a long cane that should be considered in the development of a mathematical model. Once this has been completed, a validation of the model must be completed.

METHODS: The methods included the identification of the following elements of the cane technique (e.g. cane length, sweep width, stride length, hand height, hand position, in step, shoulder width, foot displacement, foot size, foot splay, heel position, arc offset, tip off the ground, maximum height of cane tip). A mathematical model of mobility with a long cane was developed and this model was translated into a computer code so that it could be run on a standard desk-top personal computer. This model was the validated using biomechanical analysis of individuals using a long cane.

FINDINGS: A model was developed, validated, and a software program called RoboCane, and a software program called RoboCaner was developed and marketed.

CLINICAL RELEVANCE: The software product RoboCaner, has provided information and data that challenge the way the long cane has been taught over the past fifty years. Investigators have used RoboCaner to study centering the cane hand, stride length, constant contact and a high center of the arc. Also it has provided objective information to identify problems related to cane techniques and allowed the opportunity to test solutions on the computer.

FUNDING SOURCE: Core Project; Rehab R& Publications and presentations from this project.

DESIGN OF A NEW MANUAL AND MOTORIZED PRONE CART FOR SCI VETERANS
Malassigne, P, Research Service, Clement J. Zablocki VAMC, Milwaukee Professor, Industrial Design, Milwaukee Institute of Art & Design. Nelson, A L., RN, Ph.D., Associate Chief Nursing Service for Research, James. A. Haley VA Hospital, Tampa. Cors, M W, Dept. of Physical Med. & Rehab., Medical College of Wisconsin

OBJECTIVES: Design of a new manual and motorized prone cart for individuals with SCI.

RESEARCH PLAN: Before redesign, existing prone carts were evaluated and found to have severe deficiencies: they interfered with activities of daily living, with socialization and provided inadequate body support.

METHODS: An iterative process of design, prototype fabrication and evaluation was used to design the new prone carts:

FINDINGS: 1. Manual prone cart - The cart is designed with an angle adjustable torso support; padded front deck with elbow support; a front pull-out drawer; contoured body support; a frame forming an all around protective bumper and a foot guard. The cart is made with 38 mm steel tubing and is 190 cm long, 76 cm high, 75 cm wide and has a 106 cm wheel base for access to a van.

  2. Motorized prone carts - Incorporating the same features as the manual version, they are powered by two Dynamic Controls electric motors and controller unit. The hospital version has the same dimensions as the manual cart. The home version is shorter in length: 165 cm.

CLINICAL RELEVANCE: The new prone carts feature an articulated torso support that elevates the users, as well as provides a variation in postures to aid in comfort, pressure relief, and completion of activities of daily living. The new carts were successfully evaluated at the Tampa and Milwaukee VA SCI centers.

FUNDING: Manual prone cart: DVA, Rehabilitation R&D Service and NIDRR. Motorized prone cart: DVA, Rehabilitation R&D Service

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Last revised Wed 05/05/1999