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[307] TEAM CHARACTERISTICS AND PATIENT OUTCOMES ON VA REHABILITATION SERVICES
Dale C. Strasser, MD; Joseph G. Ouslander, MD
Rehabilitation Research and Development Center, Atlanta
VA Medical Center, Decatur, GA 30033 email:
dstrass@emory.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #E835-3RA)
PURPOSE--The purpose of this 3-year multisite study is to investigate the relationship of team characteristics to outcomes on VA inpatient Physical Medicine and Rehabilitation Services (PM&RS). Comprehensive measures of team, hospital, and client characteristics will be studied in relationship to functional outcomes as measured by the Functional Independence Measure (FIM).
METHODOLOGY--Approximately 52 inpatient rehabilitation teams that subscribe to the FIM are participating in the study. These hospitals represent practically all (>95 percent) VA hospitals with inpatient rehabilitation services. Project staff conduct a 1-day visit at each hospital to administer questionnaires and interviews concerning team functioning and organizational culture. FIMs, and hospital descriptive data are being obtained from archival files at PM&RS Headquarters. Team questionnaire data will be merged with client data and with descriptive organizational data and appropriate analyses conducted.
PROGRESS--Twenty-eight of the 52 data collection sites have either been completed or are scheduled in the near future. The remaining sites are in various phases of the VA R&D and University IRB research approval processes. Preparations are being made to download archival data from PM&RS Headquarters.
FUTURE PLANS--Rehabilitation teams are cost- and labor intensive. We plan to use the results of this study to develop cost-effective rehabilitation services by identifying those aspects of team functioning that are associated with good outcomes. Results will provide direction for training that will best enhance the teams' unique contributions to patient recovery, and aid in the development of integrated systems of care.
[308] LONG-TERM STRENGTH TRAINING AND FUNCTIONAL STATUS IN OLDER ADULTS
L. Jerome Brandon, PhD; Lisa Boyette, MEd; Beth Sharon,
MS
Rehabilitation Research and Development Center, Decatur
GA 30033; email: Boyette.Lisa_W@Atlanta.VA.gov
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #E721-4RA)
PURPOSE --This 3-year study is designed to investigate the effects of a 2-year muscle fitness program (strength and flexibility training) on four groups of 30 older participants each. The groups are composed of controls who receive the strength training intervention (TYPICALEX), controls who continue regular lifestyle patterns (TYPICALREG), diabetics who receive the exercise intervention (DIABEX), and diabetics who continue their regular lifestyle patterns (DIABREG).
METHODOLOGY--A repeated measures experimental design is being employed in this study. Outcome measures include muscular strength and endurance, body composition, muscle mass, flexibility, functional status, exercise adherence, and quality of life. We are recruiting volunteer controls (age 65-85) for TYPICALEX and TYPICALREG and diabetic volunteers (age 50-70) age) for the DIABEX and DIABREG samples.
Muscle strength and endurance will be measured by a Chattanooga KIN-COM Isokinetic System and for one repetition maximum (1RM) on a Nautilus multi-station system. Balance will be evaluated by a Neurocom Equitest Dynamic Posturography device. Body composition will be assessed using a Harpenden skinfold caliper which has a measurement scale precision of 0.2 millimeters (mm). Muscle mass will be estimated from circumferences and skinfolds. Flexibility will be assessed using a goniometer which measures the actual range of motion for each specific joint. A modification of the Physical Performance Test (PPT) will be used to assess functional ability.
The 1-hr (50 min strength training, 10 min flexibility exercises) training sessions will be held 3 days a week for the first 6 mo, and at least twice weekly thereafter. The subjects will complete three sets of 8-12 repetitions at each of 50, 60, and 70 percent of their 1RM. Subjects will be measured at 6-mo intervals during the training interval.
PROGRESS--The project is well underway, with the recruitment process in full force and data collection progressing. Thirty TYPICALEX and 15 DIABEX have completed pre-testing and are presently training; some have completed their initial 6-mo evaluation. Ten 10 TYPICALREG and 10 DIABREG have completed initial testing.
PRELIMINARY RESULTS--Initial results show that the subjects are increasing in strength following the strength training intervention.
[309] A STUDY OF VA STROKE REHABILITATION SERVICES AND PATIENT OUTCOMES
Helen M. Hoenig, MD, MPH; Ron Horner, PhD; Jody Clipp,
PhD, RN; Lauren McIntyre, PhD; Rick Sloane, MPH; Michael
Zolkewitz, BS; Byron Hamilton, MD, PhD; Pamela W. Duncan,
PhD
Durham VA Medical Center, Durham, NC 27705;
email: hoeni001@acpub.duke.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #F2007-RA)
PURPOSE--We seek to determine whether there are differences in patterns of stroke rehabilitation services, and, if so, whether these different patterns result in different client outcomes.
METHODOLOGY--We sampled all 166 VA facilities present in FY 1995, some of which did not have pertinent data, resulting in a final sample size of 161. We identified 12,626 veterans discharged from a VA hospital between June '95 and May '96 with either an ICD-9-CM code for acute, non-hemorrhagic stroke with a primary diagnosis (DXLSF) of ICD-9-CM 430-432, 434, 436; a DXLSF for rehabilitation (ICD-9-CM code V57) plus a secondary diagnosis related to stroke or late effects of stroke (ICD-9-CM 433, 435, 437, 438, 342); or a DXLSF of transient ischemia (ICD-9-CM 433) or occlusion/stenosis of the precerebral arteries (ICD-9-CM 435) plus a secondary stroke-related diagnosis (ICD-9-CM 342, 430-432, 434, 436).
We looked at such predictor variables in rehabilitation settings as systemic structure, personnel, and physical setting for care, defined according to resources and organization; among the veterans we considered age, race, comorbidity index, and use of a feeding tube, Foley catheter or intubation during the index hospitalization; and we considered the teaching status, referral center, and acute care resources (e.g., ICU, physician specialists) among the facilities. As outcome variables, we considered the discharge destination from acute care; the length of stay in acute care; the number of readmissions following discharge from acute care; and mortality at 6 months.
We obtained our data from facility surveys (acute care in 1994-95 and rehabilitation in June 96), from computerized data sources both inside the VA (PTF and PAID Data Bases) and outside the VA (Uniform Data System, UDS-MR); and from VA administrative sources (e.g., listings of special programs). The rehabilitation survey was based on our conceptual model for rehabilitation services; questions were developed in collaboration with expert clinicians and researchers; it was piloted at four VA medical centers diverse in volume of acute stroke patients, in organization and resources for rehabilitation, and in geographical location. We conducted beta testing at the eight medical centers in VISN 6.
We reduced the data by eliminating variables with bad or unreliable data, duplicate data, or high levels of missing data; by identification of marker variables (within categories of variables, markers variables were selected using physical therapists at the rehabilitation provider level and physiatrist at the physician/facility level); and by summarizing across selected categories of variables at the rehabilitation provider and facility level. The variables remaining will undergo factor/cluster analysis. Identified factors/clusters will be reviewed against our original conceptual model and by an expert panel, who will help weight variables for summary scores and select marker variables for each cluster. Bivariate analyses with our outcomes will be done for potential marker variables. The final summary scores and marker variables will then be analyzed in separate multivariable regressions, which will examine their relationship to patient outcomes while controlling for patient and facility characteristics.
PROGRESS--Data collection, entry, cleaning, and reduction are complete.
PRELIMINARY RESULTS--Our acute care survey is 98 percent complete; our rehabilitation survey is 100 percent complete. We have found a substantial variation in rehabilitation resources nationwide. For example, average rehabilitation workloads varied from 755 units per physical therapist (PT) in the South to 362 units per PT in the West. Tuition support provided to rehabilitation was greater in academic VAs ($6,839) than in in nonacademic VAs ($3,223). Similarly, 60 percent of rehabilitation bed units in academic VAs always or almost always had adaptive toilets in patient rooms compared to 25 percent of those in nonacademic VAs.
FUTURE PLANS--We shall complete the data analysis outlined above and disseminate results.
[310] DEVELOPING VETERANS ADMINISTRATION REHABILITATION-RELATED GROUPS: A PILOT STUDY
Margaret G. Stineman, MD; David Asch, MD, MBA; Richard
Ross, MS
Department of Rehabilitation Medicine, University of
Pennsylvania, Philadelphia, PA 19104-2676; email:
mstinema@mail.med.upenn.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Pilot Project #B2063-PA)
PURPOSE--We seek to compare stroke and orthopedic patients' lengths of stay (LOS) in VA Medical Center (VAMC) inpatient rehabilitation units to those of the private sector after accounting for case mix differences, in order to determine how VAMC rehabilitation inpatients differ from those treated in the private sector. By so doing, we hope to address the need for a rehabilitation case mix measure specific to the VAMC.
METHODOLOGY--An expert panel of rehabilitation clinicians developed hypotheses on how patients with stroke and orthopedic conditions presenting to VAMCs differed from those presenting to private sector facilities. These hypotheses were tested through the development of multiple linear regression models on the logarithm of LOS (ln LOS) using Functional Independence Measure (FIMTM) data from the Uniform Data System for Medical Rehabilitation (UDSMRTM). Case-mix adjustors included the Functional Independence Measure-Function Related Groups (FIM-FRGs) along with other clinical factors. To explore need for a VAMC-specific patient classification scheme for inpatient rehabilitation, a set of VAMC-specific measures for stroke and orthopedic rehabilitation were developed and compared to private sector FIM-FRGs. The methods of development, based on recursive partitioning, paralleled those used to establish the FIM-FRGs. The VAMC-specific classification is referred to as the Rehabilitation-Related Groups (RRGs).
RESULTS--LOS in VAMC inpatient rehabilitation is nearly twice that of the private sector. As initially hypothesized, the VAMC, compared to the private sector, treats higher proportions of clients with traits associated with longer LOS, including being single, separated or divorced, unemployed or retired due to disability, being Black, and having a longer onset-to-admission interval. Even after adjustment for these case mix differences, LOS in the VAMC was longer. The RRGs, developed from the records of 5,435 clients discharged from the VAMC in 1994 and 1995, explained 15.1 and 9.5 percent of the variance in ln LOS for stroke and orthopedic patients, respectively. The RRGs defined two severity groups within the stroke and two groups within the orthopedic categories that distinguish between those with greater and lesser physical disabilities. Mean LOS for the functionally severe VAMC stroke subjects with admission motor-FIM scores less than 57 was 39.3 days, while it was 23.9 days for the functionally less severe group. Mean LOS on VAMC inpatient rehabilitation services for the functionally severe orthopedic group with admission motor-FIM scores less than 56 was 32.0 days, while it was 20.3 days for the less severe group.
In contrast to RRGs, FIM-FRGs assign stroke subjects to nine and orthopedic subjects to 13 groups. The FIM-FRGs explained 17.4 and 14.5 percent of the variance in ln LOS, respectively, for stroke and orthopedic subjects undergoing rehabilitation in the VAMC.
CONCLUSIONS--Once calibrated to reflect VAMC utilization patterns, use of the FIM-FRGs compared to RRGs would provide more detailed clinical profiles and facilitate direct comparisons of VAMC to private sector rehabilitation services. With regard to explanatory power for LOS, the FIM-FRGs would have a slight advantage over the RRGs within the VAMC. This minimal predictive advantage would occur at the expense of greatly increased complexity of the predictive algorithms. In contrast, the greater parsimony of the RRGs would reduce administrative burden in any systems of centralized monitoring or budget allocation. Because of their extreme simplicity, the RRGs would likely contain sufficient numbers of cases in each group for meaningful statistical comparisons, thus facilitating risk adjustment quality improvement efforts, even in the smaller bed units. Choice of RRGs over FIM-FRGs for use in the VAMC depends on the application and analytic objects.
[311] DEVELOPMENT OF A SYSTEM TO AID ORTHOPAEDIC SURGICAL DECISION-MAKING IN CHILDREN WITH CEREBRAL PALSY THROUGH PREDICTION OF POST-SURGICAL GAIT PATTERNS
Alan R. Morris, MASc, PEng; Stephen Naumann, PhD, PEng;
Gabriele M.T. D'Eleuterio, PhD; John H. Wedge, MD,
FRCSC
University of Toronto, Toronto, ON, Canada; Hospital for
Sick Children, Toronto, ON, Canada; Bloorview MacMillan
Centre, Toronto, ON Canada M4G 1R8
Sponsor: Easter Seal Research Institute, Suite 200, Don Mills, ON M3C 3P2 Canada
PURPOSE--In order for the best possible outcome of surgery in cerebral palsy (CP) to be realized, there is a need for physicians to have objective criteria by which to analyze walking patterns and decide on the type of intervention for individuals. The purpose of this project is to develop a computer software tool that would be used to assist surgeons in planning orthopaedic surgery specific to CP to give them the ability to predict the results of their surgery through seeing simulated walking patterns prior to surgery.
METHODOLOGY--The approach to solving this problem is through two steps: the simulation of walking for a given input signal, and the synthesizing of new input signals, based on historical data. In order to simulate walking, it is necessary to collect system input (muscle electromyographic signals) and system output (movement patterns) for various subjects. An adaptive controller will be developed to derive realistic time-varying muscle force patterns that will drive a biomechanical model (in software) to replicate recorded movement. This will be done through developing the software model with appropriate lower-level (spinal cord) sensory feedback loops, a realistic optimization rule based on the input data, and the use of adaptive artificial neural network controller methods to arrive at the control patterns. Once realized, the operator will be able to provide starting conditions and a muscle profile pattern, and derive movement of the biomechanical model.
A second component will focus on surgical outcome. A database of surgical subjects (pre- and post-operative), containing motion analysis data, muscle activation data, and measures of subject spasticity and range-of-motion will be developed. A model will be developed to determine transformations of muscle-activation patterns before and after surgery. This will provide a means of predicting how a muscle-activation pattern may be changed due to a particular surgery. Once developed, this model could be used in combination with the movement model to predict post-surgical movement patterns for children with CP.
PROGRESS--This project is just beginning.
[312] DEVELOPMENT OF CLINICAL PROTOCOLS BASED ON ERGONOMICS EVALUATION IN RESPONSE TO AMERICAN DISABILITY ACT OF 1990
Sheldon R. Simon, MD; Mohamad Parnianpour, PhD; William
S. Marras, PhD; Kinda Khalaf, MS; Patrick Sparto, MS
The Division of Orthopaedics, and Industrial, Systems
and Welding Engineering, The Ohio State University,
Columbus, OH 43210; email: Simon.1@osu.edu;
parnianpour.1@osu.edu; wmarras@magnus.acs.ohio-state.edu;
khalaf.1@osu.edu; sparto.1@osu.edu
Sponsor: National Institute for Disability and Rehabilitation Research, Rehabilitation Engineering Research, Washington, DC 22202
PURPOSE--We are working to develop a series of models that could be used in the process of employment and rehabilitation of injured workers under the ADA. More specifically, the goal is to develop models that can successfully predict the requirements of industrial tasks. These models would be used for both analysis and simulation purposes. Once these models are validated, they could be used with documentation of subjects' functional capabilities to prescribe job-specific rehabilitation programs and/or assistive devices, that would enable individuals to perform the essential functions of the job.
METHODOLOGY--The requirements of a task have often been quantified in terms of the motion and forces needed to complete it. An often neglected aspect is that in many cases it must be performed repetitively over the duration of a shift. Hence, the maintenance of the forces and motions over an extended period of time must also be considered. Therefore, a goal of the employment or rehabilitation of a disabled worker is to make sure that a given task can be performed not once, but for the entire duration that the job requires.
The development of models that can predict the endurance, as well as assess the degree of fatigue in workers, has been a major focus of this project. Because the threat of pain or injury necessarily prevents the performance of maximal exertions by injured workers, it is important to develop the clinical protocols and models using data from submaximal exertions. Once the models are validated, the ability to predict the endurance based on the performance of relatively few submaximal exertions will be possible. The attributes of our developed protocols are enormously important, since the employer may not be able to inquire about prior or existing disabilities of the prospective employee. The use of submaximal exertions reduces the risk of reinjury to the applicants/injured workers.
PROGRESS--We have developed several testing protocols for the quantification of trunk muscle strength and endurance during diverse sets of fatiguing submaximal tasks: constant torque isometric exertions; sustained varying torque isometric exertions; repetitive dynamic lifting and lowering exertions; isokinetic single-joint testing to generate 3-D dynamic strength responses as a function of joint angle and velocity; and quantification of kinematic and kinetic data variability during multilink coordinated manual material handling task.
Another experiment was performed in order to simulate a greater number of industrial conditions that include dynamic repetitive exertions. Sixteen nonimpaired male controls were recruited to perform repetitive dynamic trunk extension exertions at two relative torque levels and two repetition rates. Doubling the repetition rate to 10 per min caused a greater decrement in the endurance time than doubling the relative torque output to 70 percent. Hence, workers returning to their job may benefit from activities that have low repetitions. The findings also reflect the need to stress the acquisition of endurance during the rehabilitation.
Models are being developed to predict the endurance time based on parameters obtained from the noninvasive surface EMG of the trunk extensor muscles. Both short-time Fourier transform and wavelet transform techniques are being used to process the EMG.
Biomechanical simulation models provide a time and cost effective tool for answering "what-if" questions. A computer-based simulation program of multilink coordinated lifting that predicts the optimum motion pattern(s) required to perform a wide range of lifting tasks subjected to constraints based on experimental strength profiles has been developed.
[313] COMORBIDITIES AND COMPLICATIONS IN STROKE: INCIDENCE, RISK FACTORS, AND EFFECTS ON OUTCOMES
Elliot Roth, MD; Allen Heinemann, PhD
Rehabilitation Institute of Chicago, Chicago, IL
60611
Sponsor: Department of Education, National Institute on Disability and Rehabilitation Research, Washington, DC 22202
PURPOSE--Individuals who sustain a stroke may be as disabled by the consequences of associated medical conditions as by the stroke itself. This study is designed to investigate clearly and systematically the incidence, risk factors, and impact on rehabilitation outcomes of preexisting conditions and medical complications of stroke.
METHODOLOGY--Data have been collected on the 1,340 patients admitted to the inpatient stroke rehabilitation service from December 1993 through May 1997. Demographic, stroke, medical comorbidity, and other information has been collected on 1,201 patients and entered into the database. Laboratory results and data on secondary complications have been reviewed for 1,000 of those patients. Impairment disability measures have also been collected on these same 1,000 patients.
PROGRESS--The most common preexisting complications found in our stroke population to be hypertension, a history of smoking, and diabetes. Other preexisting complications of clinical significance include coronary artery disease, myocardial infarction, congestive heart failure, and atrial fibrilliation. The most frequent complications developed during the acute hospitalization were urinary tract infections, pneumonia, hypertension, pressure sores, seizures, and anemia. The most common complications developed during acute inpatient rehabilitation include urinary tract infections, joint and soft tissue pain, electrolyte abnormalities, and depression. It is significant that 25 percent of stroke survivors seen for acute inpatient rehabilitation did not develop any secondary medical complications. Information from routine laboratory tests also has been collected. Almost one-third of patients have low serum albumin on admission to rehabilitation and that 38 percent have low levels of hemoglobin.
[314] DEVELOPMENT OF CLINICAL PROTOCOLS BASED ON ERGONOMICS EVALUATION IN RESPONSE TO AMERICAN DISABILITY ACT (1992)
Mohamad Parnianpour, PhD; William Marras, PhD; Sheldon
Simon, MD; Kinda Khalaf, MS; Patrick Sparto, MS
The Biodynamics Laboratory, The Ohio State University,
Department of Industrial, Welding, and Systems Engineering,
Columbus, Ohio, USA 43210; email:
parnianpour.1@osu.ed
Sponsor: National Institute for Disability and Rehabilitation Research, Rehabilitation Engineering Research, Washington, DC 22202.
PURPOSE--The Americans with Disabilities Act (ADA) of 1992 ensures equal opportunity in employment for the 43 million Americans who have disabilities. Title I of the ADA prohibits employment discrimination against people with disabilities who are qualified to perform the essential functions of a job.
The objective of this project has been to develop a series of clinical protocols and biomechanical models that could be used in the process of employment and rehabilitation of injured workers given the ADA. More specifically, the goal is to develop protocols that can quantify and models that can successfully predict the functional requirements of industrial tasks and functional capacity of healthy and impaired individuals.
METHODOLOGY--The proposed novel clinical protocols are based on submaximal exertions to avoid the confounding factors of fear of injury and pain provocation that may occur during the maximum voluntary exertions that are currently used. In addition, using the parameters that are based on the spectral distribution of trunk muscle activities, we are to obtain the trunk muscle endurance capability which is significant for two reasons: 1) the ability to perform repetitive submaximal exertions of a task demand is important in the return to work or rehabilitation of injured workers; and 2) the spectral parameters of EMG may be more objective since they cannot be voluntarily controlled by the individual, as can strength, range of motion, or speed of movement.
Biomechanical models have been used for both analysis and simulation manual material handling tasks. Once these models are validated, they could be used with documentation of subjects' functional capabilities to prescribe job-specific rehabilitation programs and/or assistive devices, that would enable individuals to perform the essential functions of the job. Manual material handling tasks have been the focus of our attention due to its pervasiveness in industry, and the trunk muscles and spine were selected for the most detailed investigation due to the observation that a large proportion of ADA cases involve low back disability.
PROGRESS--We have developed the following testing protocols for the quantification of trunk muscle strength and endurance during diverse sets of fatiguing submaximal tasks: a) constant torque isometric exertions; b) sustained varying torque isometric exertions; c) repetitive dynamic lifting and lowering exertions; d) isokinetic single-joint testing to generate 3-D dynamic strength responses as a function of joint angle and velocity; e) quantification of kinematic and kinetic data variability during multilink coordinated manual material handling tasks; f) simulation of trunk motion with and without impairment; and g) development of models to predict triaxial isometric trunk strength.
RESULTS--While quantifying the trunk muscle recruitment during the isometric tasks, it was observed that as the subjects fatigued, muscles other than the primary trunk extensors became more active. The implication of this finding is that if a worker has a deficit in either the primary or secondary muscles, risk of injury may increase. Using a database of motion profiles from a manual lifting experiment, the Karhunen-Loeve Expansion (KLE) was shown to be quite effective for representing the various motion profiles, where the number of basis vectors (eigenvectors) and coefficients needed to accurately represent the data were substantially smaller than the original data set resulting in lower order space or dimension.
FUTURE PLANS--The development of several other models are planned for the upcoming year. For one, it is of interest to predict multilink coordinated lifting strength based on isolated joint strength. Twenty subjects have been tested in order to develop this model. The determination of which wavelet-based parameters are most robust in the quantification of fatigue will also be a focus. Most importantly, the validation of the models with a low back impaired population is planned for the upcoming year.
[315] RELATION OF REHABILITATION INTERVENTION TO FUNCTIONAL OUTCOME
Allen W. Heinemann, PhD, ABPP
Department of Physical Medicine and Rehabilitation,
Northwestern University Medical School; Rehabilitation
Services Evaluation Unit, Rehabilitation Institute of
Chicago, Chicago, IL 60611-4496; email:
a-heinemann@nwu.edu
Sponsor: National Institute on Disability and Rehabilitation Research, Washington, DC 22202; The American Occupational Therapy Foundation, Bethesda, MD 20892
PURPOSE--A clear relationship between medical rehabilitation therapy and functional outcome has not been demonstrated. We have assumed that "more of the right kind" of therapy results in better functional outcomes; however, there is little objective evidence to support this assertion. Recently, employer concerns about health care cost escalation has led to efforts to reduce costs and lengths of stay. We urgently need to describe objectively what the "right" kind of therapy is. Cost-effective, competitive rehabilitation services will be based on a clear understanding of what resources and strategies result in the most desirable outcomes at least cost. It is the purpose of this project to objectively measure and then demonstrate relationships between therapy type and extent of functional outcomes, based on recently developed methods. Preliminary studies have illustrated the motor and cognitive recovery attained by patients undergoing comprehensive medical rehabilitation, and moderate correlations with nursing time and some billed services but not others, including occupational therapy. Further study is needed to identify relationships between impairment and disability, the extent to which rehabilitation goals are met, and barriers to goal attainment and functional recovery.
The specific aims of this 4-year study are to:
METHODOLOGY--Three impairment groups were included: persons with stroke, traumatic brain dysfunction, and spinal cord dysfunction. These groups are among the largest populations served by inpatient rehabilitation programs. Data were collected from seven subscribers to the Uniform Data System for Medical Rehabilitation (Rehabilitation Institute of Chicago, Lutheran General Hospital, Mid-America Rehabilitation Hospital, Erie County Medical Center, The Institute for Rehabilitation and Research, Baylor Institute for Rehabilitation, and Long Beach VA Medical Center); a sample of 300 was collected through July 1997. Collection of follow-up data and cleaning and entry of data will continue through the year.
For each subject, Functional Independence Measure (FIM) scores were assessed weekly by nursing staff; nursing activities were collected during a 24-hr period weekly; therapy hours were extracted from bills; and therapy activities and goals, comorbidities, and barriers were summarized. An advisory identified, reviewed, and approved a list of rehabilitation goals, therapy activities and interventions, barriers to goal attainment, and comorbidities.
PROGRESS/PRELIMINARY RESULTS--In a preliminary analysis of data, a significant correlation (r=0.36, p<0.05) was found between the intensity (units/day) of occupational therapy and goal attainment in subjects who achieved between 40 and 100 percent of their goals; that is, more intense therapy was associated with greater goal attainment. There was a nearly significant relationship between length of stay and percent goal attainment (r=0.28, p=0.09) such that those with longer rehabilitation stays attained more of their goals. For specific occupational therapy goals, persons who received more intense occupational therapy were more likely to attain grooming (p<0.02), bathing (p<0.03), eating (p<.05), functional communication (p<.05), and community integration (p<.01) goals.
Gains in motor function as measured by the FIM were positively correlated with both the total number of occupational therapy units (r=0.43, p<.01) and intensity of occupational therapy (r=0.27, p<.05); that is, subjects who received more total occupational therapy service and more intense services (hours/day) made larger FIM-measured motor gains. Gains in cognitive function as measured by the FIM were positively correlated with total occupational therapy units (r=0.57, p<.01), but not intensity of services.
Therapists reported barriers to goal attainment using a list of 42 barriers. We used multifaceted rating scale analysis to calibrate the vulnerability of each goal to nonattainment and the likelihood of each barrier occurring. Slow neurologic recovery was the most frequently cited barrier followed by cognitive, behavioral, motivational, and emotional problems. Occupational therapy goals which were most often impeded were lower and upper body dressing, toileting, and bathing.
IMPLICATIONS--Intensity of occupational therapy was related to goal attainment for some, but not all, goals. Larger functional gains in bathing, grooming, functional communication, client-caregiver education, and community education were seen in those who received more intense occupational therapy. Improvement in cognitive function from admission to discharge and goal attainment were strongly correlated, suggesting that improvement in cognitive status may explain goal attainment. Goal setter variability may explain some of the nonsignificant relationships. Some therapists may be better predictors of potential improvement, while others may set unrealistic goals. Course of impairment reduction appears to be the rate-limiting factor in disability reduction. Dose effects of therapies are not simple and uniform. Some therapies achieve impairment remediation (particularly speech therapy), while occupational therapy achieves disability reduction. Benefits of therapy may be reflected in skills other than those which were the explicit focus of treatment. Course of impairment and disability reduction varies across impairment group. Providing the right dose of rehabilitation therapies is an art which must be described better. Ongoing work will examine the effects of comorbidities and complications on functional gains. Selecting the optimal setting for rehabilitation and therapy intensity could be guided by dissemination of the project's final results.
[316] TESTING OF POLYURETHANE FOAMS TO DETERMINE THEIR STRESS-STRAIN RELATIONSHIP
Thongsay Vongpaseuth, BS; Beth A. Todd, PhD
The University of Alabama, Tuscaloosa, AL 35487-0276;
email: tvongpas@eng.ua.edu;
btodd@coe.eng.ua.edu
Sponsor: The University of Alabama, College of Engineering, Tuscaloosa, AL 35487
PURPOSE--Polyurethane foam (PU) is commercially available, lightweight, easy to handle, durable, inexpensive, easily modified for body fitting, and widely used for various medical applications. PU has been used for such things as wheelchair cushioning, postural positioning, head and back support, pediatric immobilization, shoe insoles, and prosthetic limb interfaces. Institutionalized elderly and disabled individuals who sit motionless for many hours during the day are at a high risk for developing decubitus ulcers. Knowing the material properties of these foams will help in achieving the design goal of pressure relief at the human interface. The objective of this study is to investigate the mechanical properties of cushioning foam by performing compression tests on three types of PU in accordance with the American Society for Testing Materials (ASTM) standards.
METHODOLOGY--For this study, the Indentation Force Deflection (IFD) Test for both specified deflection and force are used to determine the stress-strain relationships of the PU. The IFD with specified deflection was used as a large deformation test. The foams used for this study are Fire Resistant (FR) PU, #6 PU, and PU Beige. These materials were tested according to ASTM D-3574-95, Standard methods of testing flexible cellular materials--slab, bonded and molded urethane foams. This test consists of measuring the force required to compress the foam by 25 and 65 percent of its original thickness. The IFD with specified force was used as a small deformation test. This force deflection test is determined by measuring the thickness of the foam under a force of 4.5 N, 110 N, and 220 N. The standard specifies that the test specimen must be an entire product or a suitable portion of it, with the further specification that the specimen should have dimensions not less than 380×380×20 mm. A circular indenter with a diameter of 203 mm should be used on the test specimen. Several rectangular samples (38.1×38.1×10.2 cm, 30.5×30.5×10.2 cm, 4×4×5 cm) and 10.2 cm high cylinders with a 10.2 cm radius of each material were tested with two different testing machines. Initially, stress-strain data were collected on a strip chart recorder, but in latter stages of testing, a data acquisition system was used.
PROGRESS--Data collection is complete. Analysis on the linear (small deformation) regimes of the PU's stress-strain curve is completed. Currently, analysis on the nonlinear region (large deformation) of the stress-strain curve is underway.
RESULTS--Test results varied according to the relationship between the size of the test specimen and the indenter. At large strains, the larger and medium size blocks carried a much larger stress than the cylinder and smaller block. This is partly due to the shear force between the material and the sides of the indenter for the large specimens. The effect can also be explained through the theory of elastic foundations. In this case, deflection under the indenter is a function of rotation, reaction moment, and reaction force throughout the cross-section of the foam.
FUTURE PLANS--We shall complete analysis of the nonlinear portion of the stress-strain curve.
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