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[112] IMPROVEMENTS IN A NEW TECHNIQUE FOR INCREASING MOVEMENT AFTER STROKE
Rama D. Pidikiti, MD
Birmingham VA Medical Center, Birmingham, AL 35233
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #B1692-RA)
PURPOSE--We seek to confirm our preliminary observations that the incapacitating motor deficit of many persons with stroke can be substantially reduced, and their functional independence greatly increased, through the use of techniques involving Constraint-Induction (CI) therapy. The CI techniques tested to date include restriction of movement of the unaffected upper extremity by a sling and training of the affected upper extremity for 2 wks. The main objective of this project will be to develop and test two modifications of this technique in an effort to improve its effectiveness for those suffering the chronic effects of stroke, whose functional independence has been significantly compromised by motor deficits.
METHODOLOGY--We shall test two modifications: first, we shall decrease the intervention time from the current 2 wks to 1 wk, to determine whether the procedure can be made more cost effective, and second, we shall apply the intervention to subjects with greater motor disability than have been worked with to date (an estimated 20 percent of the chronic stroke population with motor deficit), to determine whether it is possible to expand the number of those who can benefit from the therapy in the next lower functioning 40 percent of the population.
The research will be carried out with 80 chronic stroke subjects at the Birmingham VA Medical Center. Veterans will be identified by chart review and screened by telephone calls. Those found to be eligible will be asked to come to the clinic for informed consent and further testing. Those subjects meeting inclusion criteria will undergo a baseline battery of tests, including objective measures of motor function, ADL function, joint range of motion, and cognitive status. A self-report and caregiver report of ADL function will also be obtained. The number and severity of comorbidities will be assessed using the Comorbidity Damage Index of Charlson. Subjects will then be randomly assigned to one of the two groups to be studied in each of the two phases of the project.
In Phase 1, the results of 20 subjects given a 1-wk period of CI treatment will be compared with the results of 20 subjects in a comparison group given conventional physical therapy for 1 wk and the results already obtained from subjects given the 2-wk CI procedure. In Phase 2, the 2-wk CI procedure will be employed with two groups of 20 subjects each at the two lower levels of motor functioning (just below those we have tested until now), thereby obtaining CI therapeutic efficacy data for an estimated additional 40 percent of persons with motor deficit from chronic stroke effects. Treatment will be administered on an outpatient basis. Follow-up testing will be carried out at the end of each of the first 4 wks after the end of treatment and again 6 and 12 mo posttreatment. Follow-up testing will include measures of motor function and joint range of movement (at 6 and 12 mo posttreatment) and of ADL function (at each follow-up point).
PROGRESS--Ten control subjects have been tested who were given a general fitness placebo control intervention involving the same time period (2 weeks) and the same intensity of therapist-subject interaction (6 hr/day for 10 consecutive weekdays) as our previous subjects given CI Therapy. None of these subjects showed a significant improvement in upper extremity function. They, therefore, constitute a successful placebo control intervention. Ten more control subjects will be given the same intervention during the next year. Four lower functioning subjects who did not meet the project's former minimum motor criterion have been tested. Contrary to expectations, these subjects improved as much with CI Therapy as our previous higher functioning stroke patients. If these results hold up, it will indicate that CI Therapy is applicable to at least 50 percent of the chronic stroke population with motor deficit, and perhaps more--a much larger number than we previously thought would be amenable to therapy.
[113] LIMB MANIPULATION UNDER PATIENT CONTROL: A PILOT STUDY
Charles G. Burgar, MD; H.F. Machiel Van der Loos, PhD;
Peter S. Lum, PhD; Deborah Kenney, OTR
Rehabilitation R & D Center, VA Palo Alto Health Care
System, Palo Alto, CA 94304; Department of Functional
Restoration, Stanford University Medical School, Stanford,
CA 94305; Web: http://guide.stanford.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Pilot Project #B1846-AP)
PURPOSE--Stroke is the most common inpatient rehabilitation diagnosis, and its prevalence in DVA patients is increasing as aging WW II veterans join the population at highest risk. Upper limb paralysis is often resistant to therapeutic efforts. The resulting mobility and self-care impairments negatively impact discharge to the community and length of stay. Until significant gains take place in prevention of stroke and its sequelae, more effective methods are needed to maintain or restore the dexterity necessary for daily activities. This pilot study tested the concept and feasibility of a semiautomated therapy system for rehabilitation of post-stroke hemiplegia.
METHODOLOGY--We evaluated the utility of an electromechanical apparatus that allows patient control of passive or actively-assisted movements: the Mirror-Image Movement Enabler (MIME). Normally, this technique is implemented by a therapist who moves the paretic limb as the client either remains passive or actively attempts to contribute to the movement. We measured the external and subject-generated forces associated with programmed and self-directed movements during a simple tracking task and correlated these forces with the level of motor recovery of the subjects.
In programmed mode, pre-determined movements of the paretic arm were facilitated with the assistance, as necessary, of external forces applied by a small industrial robot. In the subject-controlled mode, movements of the nonaffected limb ipsilateral to site of cerebrovascular accident were sensed by position encoders, reflected symmetrically about the sagittal plane, and reproduced in the paretic limb with assistance of the robot. A six-axis transducer measured the assistive forces during movement, and optical sensors quantified motion.
PROGRESS--Six controls and 13 persons with hemiplegia participated in this pilot study.
PRELIMINARY RESULTS--MIME facilitated movement of one arm of each subject, both in programmed mode and in trajectories determined by voluntary contralateral arm movements. Performance of stroke subjects reflected their level of recovery. Overall, the more impaired subjects produced higher force values than less impaired subjects, but these forces were often misdirected relative to the direction of movement, and relative to the force directions when their contralateral limb performed the movements. There was a negative correlation between the force magnitude error vs. the FM score (p<0.02). We also observed performance differences between programmed and subject-controlled modes, with moderately to severely impaired subjects producing more effective forces over portions of the movement trajectories that were dependent on the control mode.
This pilot work demonstrated that patient-guided manipulation therapy of the paretic limb is feasible, and that forces measured by MIME correlate with the state of motor recovery, as measured by the Fugl-Meyer scale.
FUTURE PLANS--We propose to further study the use of assisted movement in recovery of upper limb function following stroke, investigating the utility of this technique in the very acute stages of stroke recovery, when the potential for a beneficial effect on functional outcomes may be even greater.
[114] THE ROLE OF IMAGERY IN AUDITORY COMPREHENSION IN BRAIN-DAMAGED ADULTS
Marilyn Selinger, PhD
Denver VA Medical Center, Denver, Colorado 80220
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #C818-RA)
PURPOSE--The purpose of this project is to examine the contribution of imagery as an aid to the auditory comprehension of connected language in individuals with aphasia and right-hemisphere lesions. Do imagery-laden verbal passages enhance accuracy of comprehension on verbal tasks? Do imagery-laden verbal passages increase inter- and intrahemispheric differences in persons with right and left brain-damage, as measured by probe auditory evoked potentials (AEP)?
METHODOLOGY--Using a signal-averaging program, a probe-evoked potential technique (in which a task-irrelevant sensory stimulus is superimposed on ongoing complex tasks) is used to measure intra/interhemispheric response to the task. The paradigm includes a baseline or nondifferentiating task and two language or left hemisphere tasks. The baseline task provides a comparative measurement of processing a task that has never been shown to differentially bias one hemisphere over the other. The two language tasks include passages rated as high imagery and passages rated as low imagery by normal subjects. In addition, multiple choice questions are asked following each language passage. These questions are used as measures of the subject's comprehension of the material as well as an indicator of his/her involvement in the task. The questions require both literal and interpretive conclusions to be made about the material. Persona with aphasia whose PICA Overall severity levels fall between 55th-85th percentile are included as subjects, and persons with right hemisphere damage, whose overall scores on the PICA fall between the 55-85th percentile, serve as pathological comparisons. In addition, a control group without brain damage is included. Each subject undergoes two sessions of electrophysiological testing resulting in evoked potential measures of hemispheric responsivity and test/retest data.
PROGRESS--All subjects have been completed. Data scoring and analysis is proceeding and will be completed in the next month.
FUTURE PLANS--Utilizing the results from the study, development of treatment paradigms that may be useful to the aphasic subjects will be selected and tried in the clinical setting.
[115] FACTORS AFFECTING TIME BETWEEN CVA ONSET AND REHABILITATION IN THE VA
Barbara Bates, MD
Stratton VA Medical Center, Albany, NY 12208; email:
bbates@pol.net
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #E2108-PA)
PURPOSE--According to data from the Uniform Data System for Medical Rehabilitation (UDSMR), a national rehabilitation patient database, the mean length of time between the day a patient has a stroke (CVA) and the day he is admitted to an inpatient rehabilitation unit is significantly longer in the VA healthcare system than in nonVA facilities. The reasons for this disparity are unknown. The objective of this project is to describe how rehabilitation onset-admission time for CVA patients in the VA varies with: patient social and medical characteristics, VA Medical Center facility policies and procedures, VA Medical Center external referral patterns, patient geographic distance from VA Medical Center, and patient data coding errors.
METHODOLOGY--This project is a retrospective review of persons with CVA discharged from 15 VA rehabilitation bed units in fiscal years 1995 and 1996, using both medical record information and the VA-UDSMR database. Only those admitted for their first inpatient rehabilitation for the current stroke were included; those re-admitted for the same stroke were excluded. Also excluded were persons with rehabilitation onset-admissions time greater then 365 days (n=34) or who were missing critical dates precluding the determination of onset time (n=16). The VA-UDSMR database includes patient demographic information such as date of birth, zip/postal code, living setting prior to admission, marital status, rehabilitation diagnosis, admission and discharge dates, and date of disability onset as well as functional status at admission and discharge. The medical record review of individual cases will add information regarding coding errors (CVA vs. other rehabilitation diagnoses, or new admission vs. readmission), comorbidities, and complications during the acute period of hospitalization, and a decomposition of rehabilitation onset-admission times into smaller units of time (i.e., initial referral, diagnostic consult, subsequent referral).
Data from the study sites will be incorporated into a single database and analyzed. The effect of coding errors, social, and medical characteristics will be examined using parametric (ANOVA), and nonparametric (Kruskali-Willis) tests. Linear regression will be used to examine the effect of multiple covariates (e.g., geographic distance) on rehabilitation onset-admission time. The influence of facility processes/procedure and referral pattern variables on rehabilitation onset-admission time will be examined using multivariate regression techniques.
PROGRESS--Demographic and functional data on 1045 new CVA cases admitted to the study sites during FY 1995 and FY 1996 has been extracted from the VA-UDSMR database; from this, a sample of 300 cases has been randomly identified for medical record review (20 cases per site). To date, data abstraction from medical records has been successfully completed at 5 sites and site visits have been scheduled at the remaining 9 facilities.
PRELIMINARY RESULTS--Of the 1045 new CVA cases, 98 percent were male and 51 percent were married at the time at the time of admission; 590 (56 percent) were admitted to rehabilitation from an acute unit within the same facility, 221 (21 percent) from an acute unit in another facility, and 182 (17 percent) from home. The remaining 52 (6 percent) were admitted from a variety of long-term care settings. Those admitted from an acute unit within the same facility had a onset time (mean (1SD)) of 25.4 (39.9) days. Onset-admission time for those admitted from other acute facilities was 34 (33.7) days, for those admitted from home, 51 (73.5) days, and for those admitted from long-term care settings, 73 (67.8) days. Though preliminary, these data suggest that the location from which persons are admitted plays a role in the length of time it takes to transfer them into rehabilitation settings.
[116] CORTICAL CONTRIBUTIONS TO THE RECOVERY OF MOTOR FUNCTION
Peter L. Strick, PhD; Donna S. Hoffman, PhD; Nathalie
Picard, PhD
Research Service, VA Medical Center, Syracuse, NY 13210;
email: strickp@hscsyr.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #B2013-RA)
PURPOSE--The purpose of this project is to determine which brain areas contribute to the recovery of wrist movements after damage to the primary motor cortex in monkeys.
METHODOLOGY--The experiments use functional imaging of the brain with 14C 2-deoxyglucose (2-DG) to define the pattern of cortical activation in normal monkeys when they perform step-tracking movements of the wrist. The same technique is used to define the pattern of cortical activation in monkeys that have recovered the ability to perform step-tracking movements of the wrist after removal of the arm area of primary motor cortex.
PROGRESS--We have examined the deficits in wrist movement and muscle activity in 2 monkeys after removal of the arm area of primary motor cortex. We have applied the 2-DG technique in these monkeys to determine which brain areas have increased metabolic activity during step-tracking movements of the wrist.
PRELIMINARY RESULTS--Preliminary analysis of brain tissue from one of the animals suggests that 2-DG uptake is elevated in some of the premotor areas in the same hemisphere as that receiving damage to the primary motor cortex. On the other hand, activation in the opposite hemisphere does not appear to be higher than that of normal animals. These preliminary observations suggest that recovery of motor function following damage to the primary motor cortex depends on the increased involvement of the premotor areas in the generation and control of movement.
IMPLICATIONS--Our data should enable clinicians to make more accurate predictions about the potential for and time course of functional recovery after a cortical stroke. Specifically, our studies should indicate which cortical areas are essential to the recovery of wrist movements following damage to the primary motor cortex. The potential for recovery may be good if these areas are not involved in the disease process and may be limited if these areas are involved.
[117] N-ACETYLASPARTATE: A PREDICTOR OF OUTCOME IN NEUROREHABILITATION
Steven H. Graham, MD, PhD; Lydia Bayne, MD; Lalith
Talagala, PhD
Neurology Service, University Drive VA Medical Center,
Pittsburgh, PA 15240; Department of Neurology, University of
Pittsburgh 15261; email: sgra+@pitt.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #B785-RA)
No report was received for this issue.
[118] CULTURAL INFLUENCE ON APHASIA IN AFRICAN-AMERICANS
Robert T. Wertz, PhD; Sandra B. Chapman, PhD; Hanna K.
Ulatowska, PhD;
Audiology and Speech Pathology, VA Medical Center,
Nashville, TN 37212; University of Texas, Dallas, Dallas, TX
75235; email: wertz.robert_t.@nashville.va.gov
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #C888-2RA)
PURPOSE--In this investigation we seek to determine whether traditional aphasia tests are culturally biased and to develop culturally appropriate measures for aphasia through answers to two research questions: Does performance by neurologically normal African-Americans differ from performance by neurologically normal Caucasian-Americans on traditional aphasia tests, culturally appropriate discourse measures, and culturally appropriate communication profiles? Are there differences in the severity and profile of language deficits between aphasic African-Americans and aphasic Caucasian-Americans on traditional aphasia tests, culturally appropriate discourse measures, and culturally appropriate communication profiles?
METHODOLOGY--Study participants will be 35 nonimpaired African-Americans; 35 nonimpaired Caucasian-Americans; 35 aphasic African-Americans; and 35 aphasic Caucasian-Americans. Nonimpaired subjects will have no history of neurological impairment. Aphasic subjects will be aphasic subsequent to a left hemisphere cerebral vascular accident and at least 3 mo post-onset. Two aphasia tests, the Western Aphasia Battery and the Token Test from the Neurosensory Center Comprehensive Examination for Aphasia, a discourse battery that includes four culturally appropriate tasks designed to elicit narrative discourse, and two functional communication profiles that rate communication competence in a variety of functional communication activities, will be administered to all subjects. To answer the primary research questions, analyses of variance and covariance and Chi Square analyses will be used to compare normal African- and Caucasian-Americans and aphasic African- and Caucasian-Americans on the traditional aphasia tests, discourse measures, and communication profiles.
PROGRESS--Discourse stimuli and tasks have been developed and pilot-tested for validity and reliability. Study participants are being recruited and evaluated.
[119] A CONTROLLED STUDY OF THE EFFECTS OF EMG FEEDBACK AND ELECTRICAL STIMULATION ON MOTOR RECOVERY IN ACUTE STROKE PATIENTS
John McGuire, MD; Elliot J. Roth, MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--Despite conventional rehabilitation efforts, loss of upper extremity control continues to be one of the main limiting factors determining functional independence in stroke survivors. The restoration of motor control relies on the convergence of at least three types of physiologic information: central representations of motor output encoding the goal of movement, afferent input to provide the means to monitor movement progress, and relevant data from motor memory.
METHODOLOGY--Technical difficulties that hampered subject testing early in the project have been resolved. Although staff turnover is a concern, as the project involves 10 occupational therapists, the core group has remained intact and training of additional therapists is an ongoing process. Subject recruitment has been difficult with the decrease in the length of stay for stroke rehabilitation patients. We need 4 wks to complete the treatment sessions and the average length of stay is now 22 days.
PROGRESS--Despite these limitations, randomization has continued with the low-motor patient group. Currently 36 stroke survivors with low motor function have been randomized; 27 have completed 8 to 20 treatment sessions; 9 patients did not complete treatment because of equipment failure (3), short length of stay (3), fatigue (1), and lack of tolerance to the electrical stimulation (2); and 15 have completed the 1-yr follow-up evaluation and final evaluations will be completed over next 6 mo. A database is being established for data analysis.
[120] EFFECTS OF AEROBIC EXERCISE ON YOUNG PERSONS POST-STROKE
Michele Averbuch PT; Jim Hibler PT; Elliot J. Roth,
MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--Young stroke survivors participated in an aerobic fitness program to determine the effects of aerobic exercise on fitness levels, ambulatory speed, and life satisfaction.
METHODOLOGY--A pre-post design was used to allow each subject to act as his/her own control. The first 10-wk session was the initial control period. Subject were instructed to maintain the same activity level. The aerobic walking program was introduced at the onset of the second 10-wk period. Subjects ambulated three times per week for a minimum of 20 min at their target heart rate (HR) with a warm-up and cool-down phase included in each session. Participants' blood pressure and HR were taken at the beginning and completion of each exercise session to ensure a return to baseline measures. HR and rating of perceived exertion were used to monitor subjects during baseline. An educational component was provided on a weekly basis; topics discussed were relevant to stroke rehabilitation and exercise. The final 10 wks served a the second control period, During this interval, subjects were encouraged to continue with independent exercise as performed during the previous structured walking program. Local health clubs were visited by the authors to form a liaison between community-based facilities and any interested participants, and to ensure that the specific needs of stroke survivors would be sufficiently addressed. Community reentry is an important facet that was promoted through an ongoing emphasis on safe, independent exercise for the participants throughout the study.
Sub-maximal treadmill tests were performed at the onset of participation in the study, after the first control period, after the completion of the aerobic walking program, and at the end of the second control session (At 0, 10, 20, and 30 wks).
PROGRESS--Ten subjects, 7 men and 3 women, ages 29-62 years (mean=49), were able to finish the entire protocol. Due to the length of the study (30 weeks), a number of subjects had to discontinue participation because of schedule conflicts, including return to work or school, or transportation difficulties. The initial stress test using the treadmill produced abnormal results in several cases, necessitating a return to their primary physician for further evaluation and exclusion from data collection. The stress tests themselves proved difficult with some subjects due to gait deviations and fear while using the treadmill.
Eight of the 10 subjects demonstrated an improvement determined to be statistically significant at a t value of 3.98 in life satisfaction between the pre-test and post-test 2 as measured by the Quality of Life Index,
[121] PREVENTION OF THROMBOEMBOLISM IN STROKE REHABILITATION PATIENTS
David Green, MD, PhD; Elliot J. Roth, MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--Deep vein thrombosis and pulmonary embolism are important causes of morbidity and mortality in patients who have survived a recent stroke. Complicating the efforts of rehabilitation is a vulnerability to thromboembolism, which has been shown to affect 60-75 percent of elderly stroke patients. This is a study to compare two methods of thromboprophylaxis, calf compression boots (CC) and low molecular weight heparin (LWH), to see which is most safe and effective. The end points will be to determine efficacy as the presence or absence of thrombus, as defined by venous flow studies, venography, positive V/Q scan, or pulmonary angiography. Also, to determine the safety by the presence or absence of bleeding, either intracranial (positive CT scan or MRI), or elsewhere (decline in hematocrit of >5 percent, hemoglobin >2g).
METHODOLOGY--To date, 69 subjects have entered the study; of these, 55 have completed the study protocol. Forty-nine subjects had normal venograms and five had positive venograms indicating the presence of thrombi. Four of the positive venograms were in the LWH group and one was in the CC group. One subject in the LWH group has had bleeding. Subject recruitment is ongoing, with the goal of recruting a total of 100 subjects.
Fourteen subjects did not complete the protocol for the following reasons: one had gastrointestinal bleeding (LWH group); one an infection in leg that precluded use of CC; one was a scheduling error; and one withdrew from the study (or was withdrawn by the family). In the remaining six subjects, attempts at venography were unsucessful, but there was no clincial or ultrasound evidence of thrombi.
PROGRESS--Summary of data collection at this point is as follows: None of the 69 subjects exhibited clinical evidence of thrombosis; 5/55 or 9.1 percent showed venographic evidence of thrombosis; one subject from each group had adverse events in the trial; and both methods of prophylaxis are safe and effective. The numbers are still insufficient to conclude that one intervention is superior to the other. Data collection and analyses are continuing without change in the protocol or methods.
[122] THE EFFECTIVENESS OF A TELEPHONE SUPPORT GROUP FOR STROKE CAREGIVERS
Robert Hartke, PhD; Rosemarie King, PhD; Elliot J. Roth,
MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--The study explores the effectiveness of a unique intervention for the stress of older spousal caregivers of stroke survivors. One hundred thirty-six caregivers, 60 yrs of age and older, of spouses with stroke are randomly assigned to a treatment or control group. The treatment group participates in an 8-wk professionally led educational/support group held by telephone conference calls. They are assessed upon recruitment, after the group intervention, and at 6 mo. The control group receives written material on caregiver stress and is assessed upon recruitment and after 6 mo. At the end of their control group commitment, they are entered into the treatment group, participate in a support group, and are followed for an additional 6 mo. The study hypotheses are that the treatment group shows less depression, loneliness, burden, increased health behaviors, and increased competence. The research protocol has also been revised to make the control group into a "wait list" control. In this design, control subjects go on to participate in the treatment group after completing the control condition.
METHODOLOGY--There have been no substantive changes to the study protocol during the last year. The wait list control design change executed last year has been working well in maximizing the participation of subjects and assuring that they all have opportunity to be involved in the treatment program.
All strategies for subject recruitment developed to date have continued. These include identification of eligible family members through admissions at two hospitals, newspaper articles, newsletter advertisements, circulation of flyers, and mailings with follow-up calls. Recently, the research team has been successful in obtaining a public service announcement, a short spot on a radio health program, and a TV spot on a local news program is currently being completed. These media programs have highlighted the stress of coping for a stroke survivor, and so they have also addressed the RRTC-Stroke mission of community education.
PROGRESS--A total of 122 subjects have been recruited with 10 subjects dropping out before the initial assessment. Dropouts after initial assessment and full enrollment in the study equal 28, resulting in a dropout rate of 23 percent. Current study enrollment is 84 subjects. The most frequent reasons for dropping out include: no need for a support group, spouse deceased ending their eligibility, and subject lost to follow-up. There are 40 subjects in the treatment group (33 completed) and 44 in the control group (34 completed). The research team is currently beginning the twelfth support group. It is anticipated that recruitment will end in Summer 1997 and that the last subjects will complete the study by the end of Spring 1998.
RESULTS--The most recent sample of subjects analyzed consisted of 87 spousal stroke caregivers, average age 69.7 years (SD=6.8). The majority are women (76 percent), white (74 percent), well educated (M=14.4 yrs, SD=2.7), and in long-standing marital relationships (M=41.7 yrs, SD=12.8). They have been providing care in the home for an average of 2.9 yrs (SD=4.0; M=1.5; range=1 mo-27 yrs).
The reliability and validity of the 17 item Measure of Caregiver Health was evaluated with Rasch Analysis (Rating Scale Analysis), a psychometric procedure that transforms raw summed scores to a linear (interval-level) measure and evaluates the extent to which items cohere to define a unidimensional construct. With the elimination of 1 poorly fitting item and recalibration of the scale of several others, the 16 remaining items defined a coherent measure of health with good item reliability (0.94). The overall health of caregivers was skewed in a positive direction with 80 percent of the sample reporting good to excellent health. However, 31 percent of subjects indicated substantial symptoms of depression. Thirty-six percent reported one or more unintentional injuries in the last 6 mo with about half of these attributing them to the stress of caregiving. Chi-square analyses showed that subjects reporting injuries were more likely to indicate use of medications for sleep, more days when they were too ill to care for their spouse, greater stress and poorer self-care in the last 6 mo (p<0.05) than those without report of injury. A revised measure of health was derived by eliminating the items pertaining to injury to avoid confounding the evaluation of the relationship between injury and health. Multivariate analysis of variance with multiple dependent variables (health, depression, burden, and stress) indicated a significant effect for groups (no injuries/injuries) (p<0.001); post-hoc analyses showed poorer health, greater depression and higher burden (p<0.001) in caregivers who reported injury. A second multivariate analysis of variance was completed for the same dependent variables but with the independent variable defined as 1) no injury, 2) injury not attributed to caregiver stress, and 3) injury attributed to caregiver stress. A significant difference across these three groups was found (p<0.001); post-hoc analyses showed that the caregivers attributing injury to caregiver stress reported the poorest health (p<0.002) and highest burden (p=0.001).
This preliminary analysis indicates that a coherent measure of caregiver health was developed which incorporates perceptions of health and self-care with report on the frequency of specific health- and illness-related behaviors. While the majority of the spousal caregivers indicated good health, engaged in health promoting activities and handled stress adequately, a substantial subgroup reported distress and occurrence of unintentional injury. A relationship between injury and both poor physical and emotional health was found.
[123] COURSE OF RECOVERY OF COGNITIVE-COMMUNICATIVE PROBLEMS IN RIGHT-BRAIN-DAMAGED INDIVIDUALS
Leora R. Cherney, PhD; Anita S. Halper, MA; Elliot J.
Roth, MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--Historically, it was assumed that only left hemisphere (LH) damage resulted in language deficits while right hemisphere (RH) damage had no important effect on communication. However, recent evidence suggests that the RH makes an important contribution to language processing and it is now widely acknowledged that RH stroke also results in impairments in communication. RH communication impairments are believed to result from underlying deficits in attention, memory, and perception. However, the precise relationship between communication impairment and deficits in these cognitive processes is not well understood. Appropriate rehabilitation interventions cannot be designed until a better understanding of the relationship between communication and these cognitive processes emerges. There also are very little data regarding the course of recovery of cognitive-communicative problems in persons with RH damage. Increased knowledge about the rate, amount, and patterns of recovery of communication problems in them is needed to facilitate the selection of more effective rehabilitation interventions.
METHODOLOGY--Subject recruitment has been progressing slowly but steadily. The charts of all consecutive admissions to RIC with unilateral RH stroke are reviewed weekly. This year, 13 new subjects have been recruited and have participated in the initial evaluation session. This brings our total number of subjects to 51. Seven of these subjects have been followed longitudinally over 18 mo and have now completed their 4 test sessions; 8 have been tested 3 times; and 13 subjects have been tested twice. Most of the repeated evaluations have been conducted in the current reporting period.
PROGRESS--Data analysis is underway. All cognitive tests have been scored and the discourse of all subjects has been transcribed. Preliminary analyses have focused on the changes in unilateral visual neglect over time; the relationship between unilateral visual neglect and production of informational content in a story retelling task; and on performance trends on word list recall and recognition, both in the acute stage and longitudinally over time. Additional analyses are now completed on 30 subjects; these have continued to support our findings documented last year on 20 subjects.
With regard to unilateral hemispatial neglect, results indicate that there is a relationship between production of meaningful content and performance on a test of unilateral visual neglect. Furthermore, subjects with persistent hemineglect (over a period of at least 1 yr) produced less meaningful content than subjects with a transient neglect (i.e., no neglect evident at 6 mo postonset). These findings are consistent with the objectives of the study.
With regard to word list recall and recognition, results indicate that poor performance is associated with difficulties in the encoding process rather than in the retrieval process; therefore, individuals in a rehabilitation program would benefit from practice, repetition of important information, and the imposition of a strategy that facilitates encoding. The precise relationship between performance on this task and production of meaningful discourse is yet to be examined.
[124] REDUCING MOTOR DISABILITY IN HEMIPARETIC STROKE BY MANIPULATION OF SENSORY INPUT FROM THE PARETIC UPPER LIMB: A QUANTITATIVE EVALUATION
Jules Dewald, PT, PhD; Joseph Given, PhD; Elliot J.
Roth, MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--The disability of the upper limb after a hemiparetic stroke is often perceived as one of their most frustrating experiences by stroke survivors. There are well-defined reasons for the disproportionate impact of cerebral stroke in upper limb function, such as the greater relative area of cortex devoted to upper limb control, coupled with the fact that arm motions play a major role in both activities of daily living and in the workplace. A large number of neurotherapeutic techniques claim that the effect of their respective interventions creates the best results. However, because of the absence of quantitative measures to evaluate the effect of these therapeutic interventions on limb motor behavior, little progress toward the determination of the optimum intervention protocols for impaired limb motion has been made. The broad objective of our research is to quantify how sensory input can reduce disturbed muscle synergic relations and/or spasticity and thereby improve function of the impaired limb.
We are manipulating cutaneous afferents with a mixture of Lidocaine and Prilocaine (EMLA) to observe the effects on abnormal muscle synergies following stroke on control subjects to determine the analgesic effect on various cutaneous afferent types. We investigated the ability of EMLA to selectively block specific sensory modalities as a function of time. This information would contribute to ongoing research in spasticity reduction using manipulation of cutaneous afferent activity in stroke patients. EMLA is a commercially available topical anesthetic cream which is known to produce complete anesthesia to venupuncture. However, the effects of EMLA (or any topical anesthetic) on other sensory modalities has not been investigated. We have sought to further characterize the effects of EMLA on light touch, pain, cold, heat, and vibration (30 and 130 Hz). These sensations are carried by different fiber types: light touch and vibration by A fibers, pain by A and C fibers, cold by A fibers, and warm by C fibers.
METHODOLOGY--This study was performed on a group of nonimpaired controls (n=32, 20 females, 12 males, ages 22-55) with negative medical histories. Following baseline testing, 2 g of EMLA was applied to a 3 cm diameter circle of skin over the biceps bilaterally. One application was removed after 15 min. Starting with the time of removal, the subjects were blindfolded and the application site was tested every 10 min. The contralateral application remained in place for 60 min and was tested once after removal of the cream. Light touch was tested using Von Frey hairs, pain through pin prick, cold using a 1.4 cm diameter metal weight at 0 °C, heat using a 1.8 cm diameter metal weight at 44 °C, and vibration using a motorized device with an 8.0 mm diameter surface at frequencies of both 30 and 130 Hz. The data for each sensory modality were collapsed to 'no change,' 'diminished,' or 'absent.' These descriptors were assigned ordinal values for statistical analysis. Data for heat and vibration were excluded due to confounding factors present in the testing procedure. Regression lines were fit to the group data for cold, pain, and light touch plotted as percent of population with absent sensation as a function of time. A two-factor (time and sensory modality) ANOVA was performed on the group data to determine if there were significant differences (p<0.05) in the rate of loss between modalities.
PROGRESS--Significant differences in this rate of loss were found for the 15-min application protocol. Post-hoc tests showed significant differences between cold and light touch, and pain and light touch (p<0.05). No difference was found between pain and cold. In addition, extrapolation of the regression suggested that the earliest absence of sensation from time of application of the anesthetic was 8 min for pain, 9 min for cold, and 20 min for light touch. These results suggest that EMLA affects Ad and C fibers at a faster rate than Ab fibers. This implies that a topically applied anesthetic affects nerve fibers in a manner similar to perineural anesthetic injection as found in previous studies.
The ability to selectively block different afferent fibers over time will permit the investigation of the effect of different afferent feedback on spasticity and abnormal torque synergies. We are currently testing EMLA on a group of stroke survivors (n=10) for repeatability of the findings. To date we have seen four subjects, and data analysis is ongoing, along with data collection on the remaining six. If we obtain consistent results in the stroke group, initiation of a spasticity reduction protocol using EMLA will be initiated.
[125] THE PREDICTIVE VALUE OF COGNITIVE/BEHAVIORAL MEASURES IN PATIENTS AFTER STROKE IN ASSESSING FUNCTIONAL OUTCOME
Kristi Kirschner, MD; Eric Larson, PhD; Elliot J. Roth,
MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--The major objective of this study is to examine the efficacy of neurological tests in predicting functional outcome for persons with stroke. A battery of neuropsychological tests will be administered to each subject early post-stroke. Functional outcome will be measured at 1, 6, and 12 mo post-stroke. Analyses will be done to determine the critical variable or set of variables related to functional outcome.
METHODOLOGY--In Fall 1995, we were approved by the IRB to modify the enrollment criteria. Previously we had to exclude a large number of subjects because they had a history of substance abuse or had a previous stroke. We felt that allowing subjects with such a history into the study would not significantly interfere with our ability to attribute observed cognitive deficits to strokes. By allowing more subjects into the study, we will increase our predictive power. Moreover, by liberalizing our enrollment criteria, we improve our external validity in that our sample will more closely resemble the actual population seen in clinical settings.
The rate of enrollment of subjects increased after the inclusion criteria was modified with almost twice as many subject enrolled per month. A total of 170 subjects have been enrolled and tested.
PROGRESS--As expected, we are finding substantial variability among subjects in their ability to complete the different tests in the neuropsychological battery. Deficits in motor function, vision, and receptive language ability appear to have a strong effect on test completion. One of our goals is to determine which tests can still be used when these functional limitations exist. A review of the first 58 subjects in our database show completion rates ranging from 50 subjects able to complete the Benton Facial Recognition Test to only 9 subjects able to complete the Tower of Toronto. Further data collection and analysis will take place in the next year.
[126] IMPROVING VOCATIONAL OUTCOMES OF INDIVIDUALS WHO HAVE SUSTAINED A STROKE
Deborah Crown, MS; Rita McMahon, MS; Elliot J. Roth,
MD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--The overriding goal of Vocational Rehabilitation (VR) is to assist individuals with a disability to return to work at a level appropriate to their abilities. The vocational functioning and status of individuals who have sustained a stroke is significantly less than individuals with other disabling conditions. It is strongly felt that there currently exists a lack of a focused, succinct assessment to assist the VR professional in providing cost-effective, high quality services to increase successful vocational outcomes.
The broad objective of this project is to develop a good assessment tool for proper diagnosis for VR and improve the probability of positive vocational outcomes for stroke survivors. Specific objectives of this study are to investigate the Functional Assessment Inventory (FAI) for its suitability for application to the stroke population and to identify appropriate areas of the FAI that require modifications to improve the assessment tool for that population.
PROGRESS--As of May 1996, all of the data collection and data entry for the 110 nonexperimental cases have been completed. A total of 100 cases in the experimental group have had the modified FAI administered. Data analysis on 88 of this 100 found the experimental and the nonexperimental groups to be similar in areas such as gender and race. The experimental group has slightly more subjects with aphasia. The nonexperimental group has more individuals who have completed college and were employed in professional occupations before their stroke.
Data analysis also found the average FAI total scores differ by 10 points between the Employed Group (EG) and the Not Able to Work Group (NG) at case closure. The NG included those placed in sheltered workshops, volunteer positions, and retirement. Those who could not be placed but were continuing in training had an intermediate score. Based on this preliminary analysis, it seems that the FAI is helpful for predicting the probability of vocational outcome for these individuals. It appears that this will serve as a valuable tool for assessing vocational outcomes and planning vocational rehabilitation services for the stroke population. The group receiving the FAI had a shorter length of time from intake to case closure than the nonexperimental group. In addition, the group receiving the FAI required a lower number of units of vocational rehabilitation services. It appears that using the FAI did facilitate identifying the direction for vocational planning and therefore resulted in greater cost effectiveness.
[127] COMPUTER SIMULATION ANALYSIS OF COORDINATION DEFICITS IN POST-STROKE HEMIPLEGIA
Steven A. Kautz, PhD
Rehabilitation R&D Center VA Palo Alto HCS, Palo Alto,
CA 94304
Sponsor: The Whitaker Foundation, Rosslyn, VA 22209
PURPOSE--Computer models of the musculoskeletal system now make it possible to study the motor control of multijoint movements in terms of the mechanical requirements needed to accomplish particular tasks. One of the next great challenges in biomedical engineering will be to apply this technique to help restore function to people with disabilities. It is to be expected that these models will be powerful tools for pinpointing the mechanical implications of central and peripheral nervous system deficits, for designing more effective surgical interventions, and for devising rehabilitation strategies that allow the patient to make optimum use of the function that still remains.
The focus of our research is to use computer models in conjunction with experiments to investigate deficits in the neural control of the legs in persons with post-stroke hemiplegia, a group that constitutes a sizable and growing portion of the rehabilitation population. Rehabilitation strategies that were more effective at improving their ability to walk would dramatically improve their quality of life.
METHODOLOGY--We believe that the deficits of these persons can be studied effectively using a servomotor-assisted ergometer-pedaling paradigm we have developed in the course of ongoing research. Since pedaling is a constrained movement, its biomechanics can be modeled in a straightforward fashion. However, pedaling is still complex enough to be extremely interesting from a motor control point of view. Like most leg functions, pedaling and walking can be characterized by the activation of multiple muscles to produce a force that is transmitted through the foot to the environment. All the major functions required for successful interaction with the environment can be accomplished on a servomotor-assisted ergometer, including generating isometric force, and performing positive and negative mechanical work. Furthermore, these functions can be decoupled from functions in the nonplegic leg, through use of the servomotor-assisted ergometer. Depending on the mechanics of the endpoint/environment interaction, a similar activation of muscles could result in an isometric endpoint force, mechanical work being done by the leg (positive work), or mechanical work being done on the leg by the environment (negative work).
Specifically, we propose to use a servomotor-assisted ergometer pedaling paradigm to test the hypothesis that nervous system constraints (inappropriate synergies and interlimb coupling) limit the ability of the hemiplegic person to generate the appropriate endpoint force for a desired function. In order to test this hypothesis, we propose to develop a 3-D computer simulation model of the musculoskeletal system and the pedalling task to study the inter- and intra-leg coordination responsible for producing endpoint forces to interact with different mechanical loads. With that model, we shall attempt to determine how "neural constraints" limit the ability of the person with hemiplegia to generate isometric force in a desired direction, to do mechanical work in a desired direction during discrete tasks, and to do mechanical work during cyclical tasks.
PROGRESS--Pilot data have been collected on three subjects during static positions and during pedaling. Marker arrays were attached to all segments to determine 3-D orientation. The data are still being analyzed, but preliminary analysis suggests that the tested configuration of markers was successful for determining 3-D orientation of segments and can be adopted in the experiments. Necessary instrumentation has also been built.
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