Effects of Two Different Types of Ankle Foot Orthoses on Gait Outcomes in Patients With Subacute Stroke.
Phase: NA
Conditions: Stroke, CVA, Hemiplegia, Hemiparesis, Foot Drop
Sponsor: Texas Woman's University

IRB Project Number 015-286 
 
 
IRB Project Number 015-286 
 
 
Texas Woman's University 
EFFECTS OF TWO DIFFERENT TYPES OF ANKLE FOOT ORTHOSES ON GAIT 
OUTCOMES IN PATIENTS WITH SUBACUTE STROKE 
NCT02693834  
Priya Karakkattil 
7-5-2017 

 
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Introduction 
 
Stroke is a leading cause of death and disability in the world today. About 795,000 
people are diagnosed with stroke yearly in the United States. The annual cost of stroke from 
medical services and disability in our nation is $ 38.6 billion dollars. With the advancement in 
acute stroke management, the death rate has fallen in the last decade (Executive summary: Heart 
disease and stroke statistics--2012 update.2012) but about half of stroke survivors are left with 
physical impairments such as weakness of one side of the body, altered reflexes and impaired 
sensations (Levin, Kleim, & Wolf, 2009). These impairments contribute to the poor quality of 
life and disability experienced by the survivors (Bourland, Neville, & Pickens, 2011). 
The physical impairments resulting from stroke cause gait dysfunction in a majority of 
survivors. Therefore gait rehabilitation is an important aspect of neurorehabilitation with focus 
on attaining the most functional and symmetrical gait to prevent falls from faulty gait mechanics, 
and to prevent sedentary life styles and associated comorbidities (Hesse, 2003).Ankle foot 
orthoses (AFOs) are commonly prescribed in patients with stroke to address ankle and knee 
instabilities and to restore a normal and safe walking pattern (Hesse, 2003). An AFO provides 
foot clearance during swing phase, lateral stability to the ankle in stance phase, and promotes 
good heel strike at initial contact (Simons, van Asseldonk, H, Geurts, & Buurke, 2009). The 
effectiveness of AFOs on various gait parameters has been reported in patients with stroke, but 
mostly during the chronic stages of recovery (Everaert et al., 2013; Slijper, Danielsson, & 
Willén, 2012). Systematic analyses have shown that use of various types of ankle foot orthoses 
improve walking impairments and balance, reduce energy costs, and improve knee and ankle 
kinematics in people in the chronic stage of stroke recovery, greater than 6 months since the 
 

 
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onset of stroke (Tyson, Sadeghi-Demneh, & Nester, 2013; Tyson & Kent, 2013). It is reported 
that the majority of the gait improvements occur within the first 6 months following the onset of 
stroke (Jørgensen, Nakayama, Raaschou, & Olsen, 1995; Kwakkel, Kollen, & Lindeman, 2004). 
However, a limited number of studies have investigated the effects of AFOs within six months of 
stroke onset. 
 Three reported studies have investigated the effects of using an AFO compared to not using 
an AFO within 6 months following onset of stroke. Rao et al found that the use of an AFO 
significantly improved gait velocity, cadence and step length on the affected and unaffected side 
(Rao et al., 2008). Hyun et al. found that using an AFO significantly improved VO2 peak and 6 
minute walk test scores (Hyun, Kim, Han, & Kim, 2014). Carse et al showed significant 
improvement in walking velocity, average step length and cadence with use of AFO. (Carse, 
Bowers, Meadows, & Rowe, 2014).  
There is only one reported study which looked at the effects of using two different types of 
AFOs during the subacute stage of stroke, less than 6 months following onset. The investigators 
evaluated the effects of a custom Chignon AFO, which is an articulated AFO with adjustable 
elastic straps, compared to an off the shelf polypropylene AFO. Results of this study showed that 
gait speed and knee and ankle control were significantly higher in the Chignon AFO group 
compared to the polypropylene AFO group. Additionally, participants in the Chignon AFO 
group had significantly lower spasticity than those in the polypropylene AFO group (de Sèze et 
al., 2011). 
 In a recent case series report, investigators observed that using a custom Double Adjustable 
AFO during the early stages of recovery after stroke resulted in more typical muscle activation 
patterns, gait endurance and velocity, and near normal symmetry during gait without an assistive 

 
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device or an AFO in three participants (McCain et al., 2012). The authors suggested that the 
design of the Double Adjustable AFO may have provided more peripheral mechanical input to 
facilitate pre injury motor function than the typical use of AFO which is often used as a 
compensatory strategy for gait.  The use of this type of AFO for gait rehabilitation following 
stroke in the subacute stages has not been thoroughly studied.  
Statement of the Problem 
Patients with stroke resulting in hemiparesis and foot drop are affected by gait 
impairments such as poor symmetry, decreased velocity, and decreased endurance. AFOs have 
been shown to be an effective intervention for improving gait parameters in individuals who are 
in the chronic stage of stroke recovery (Tyson, Sadeghi-Demneh, & Nester, 2013; Tyson & Kent, 
2013). Although, the majority of gait improvements occur within six months of stroke (Kwakkel, 
Kollen, & Lindeman, 2004), the effect of early bracing with different types of AFOs on gait 
outcomes has not been investigated thoroughly. 
Purpose of the study: 
The purpose of this study will be to identify whether patients in the subacute stage of 
stroke, who demonstrate foot drop, will have better gait outcomes when using a Double 
Adjustable AFO, or a Posterior Leaf Spring AFO. A secondary purpose will be to determine 
whether one week of practice significantly changes gait outcomes with either of the AFO 
conditions. 
Research Hypotheses 
The research hypotheses of this study are as follows: 

 
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1. 
There will be a difference in gait endurance measurements, gait symmetry 
measurements and gait velocity measurements at baseline when using custom Double Adjustable 
AFO compared to a PLS AFO in patients in subacute stage of stroke.   
2. 
There will be a difference in gait endurance measurements, gait symmetry 
measurements and gait velocity measurements after one week of practice when using custom 
Double Adjustable AFO compared to a PLS AFO in patients in subacute stage of stroke.   
3. 
After a week of practice, there will be a difference in gait endurance 
measurements, gait symmetry measurements and gait velocity measurements compared to 
baseline measurements, when using either custom Double Adjustable AFO or a PLS AFO in 
patients in subacute stage of stroke.   
Significance of Study 
An important goal of stroke rehabilitation is to improve gait outcomes (Hesse, 2003).  An 
AFO is commonly prescribed as an adaptive strategy to compensate for foot drop; however the 
gait outcomes have not been thoroughly investigated following the use of AFOs in the subacute 
stroke population.  Additionally, high variability of stroke manifestation makes it difficult to 
compare two groups of patients affected by stroke using different AFO designs. This study uses 
two different types of AFOs as adaptive strategies to compensate for foot drop during the 
subacute stage of recovery in the same group of patients to control for the variability of stroke 
presentation. The results of this study will provide valuable information about the effects of early 
bracing to address gait impairments in the subacute stroke population.  
Stroke is one of the neurological diseases associated with increased falls resulting in 
injury in the elderly (Eng et al., 2008). Among stroke survivors, falls commonly occur during 
walking (Harris, Eng, Marigold, Tokuno, & Louis, 2005). Gait velocity has been reported to be 

 
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significantly correlated (r=.53) with fear of falls in patients with stroke. As the gait velocity 
improves patients are less fearful of falls when walking (Rosén, Sunnerhagen, & Kreuter, 2005). 
Eighty eight percent of patients with stroke who sustained a fall reported having a fear of falling, 
leading to decreased physical activity, deconditioning, decreased participation and care giver 
dependency (Schmid & Rittman, 2009; Watanabe, 2005). Although my study is not specifically 
looking at falls as an outcome, it is reasonable to infer that improving gait outcomes could 
potentially decrease the fall risk.  
Reintegration to normal living is an ultimate goal of stroke rehabilitation. Difficulty in 
walking independently, especially outdoors, is reported as the most disabling consequence of 
stroke. (Pound, Gompertz, & Ebrahim, 1998). Even after rehabilitation, 63% of community 
dwelling stroke survivors reported dependency on others for community ambulation (Lord, 
McPherson, McNaughton, Rochester, & Weatherall, 2004). Gait velocity has been identified as a 
factor which predicts independent community ambulation in stroke survivors (Rosa, Marques, 
Demain, & Metcalf, 2014). Gait speed and gait endurance are also identified as predictors for 
community ambulation after stroke (Bijleveld-Uitman, van, & Kwakkel, 2013). Although my 
study is not looking at community ambulation specifically as an outcome, it is reasonable to 
assume that improvement in gait velocity and gait endurance with use of AFO will impact a 
stroke survivor’s ability to improve participation in the community and to decrease caregiver 
dependency.   
Methodology 
Experimental design:  
The research design for this experimental study will be a 2 factor within subject repeated 
measures 2x 2 design. The manipulated independent variables in the study will be 1) type of 

 
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AFO with two levels: (a) Double adjustable AFO and (b) Posterior leaf spring AFO and 2) 
Practice Time with 2 levels: (a) baseline, and (b) after 1 week of practice. The dependent 
variables in this study are the following: Gait endurance measured by 6 Minute Walk Test 
(6MWT), gait symmetry measured using GAITRite gait analysis system, and gait velocity 
measured using GAITRite gait analysis system. 
Participants 
 Twenty participants over the age of 18, of any gender and ethnicity, diagnosed with first 
time unilateral stroke, 4 - 20 weeks post-stroke onset, resulting in hemiparesis with foot drop will 
be recruited. The number of participants was estimated based on previously reported studies. 
Hyun et al found significant differences in gait endurance measured by 6MWT when using AFO 
compared to using no AFO with 15 participants in a similar study (Hyun, Kim, Han, & Kim, 
2014). In another study by Carse et al, gait velocity and gait symmetry were found to be 
significantly better with 8 participants (Carse, Bowers, Meadows, & Rowe, 2014). Therefore, for 
our study, the potential participant number was projected as 20.   
Participants will be recruited through a sample of convenience from Baylor Institute of 
Rehabilitation locations and through word of mouth. The physical therapists at these locations 
will be given a brief description of the proposed study and will be asked to screen for potential 
participants. Potential participants who are not able to receive a double adjustable AFO through 
their insurance, who are not able to follow two steps commands or not able to ambulate 20 feet 
with or without assistive device with a minimum level of assistance of contact guard assistance 
will be excluded from the study. Participant will also be excluded from the study if the person is 
undergoing chemotherapy at the time of research. The two step command used to assess will be 
“please stand up and walk to the door.” Additionally, participants with a diagnosis of cerebellar 

 
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stroke and participants who were not ambulatory prior to stroke onset will be disqualified from 
participation.  If the potential participant meets inclusion criteria, and does not possess any of the 
exclusion criteria and is interested in learning about the study, the physical therapist will ask the 
potential participant permission to be contacted by the primary investigator. Participants who 
meet the inclusion criteria and possess none of the exclusion criteria will be asked to volunteer 
for the study. Each participant will read or be read their rights as human subjects and asked to 
sign the informed consent approved by the Institutional Review Boards of both Baylor Health 
Care System and Texas Woman’s University prior to enrollment in this study. A Mini Mental 
State Examination (MMSE) will be performed to determine whether the participant has the 
cognitive ability to sign the informed consent. If the participant scores below 21, then a legally 
authorized representative will be asked to sign the consent. For a person who scored below 21, 
MMSE will be assessed at subsequent visits to determine whether they are able to sign the 
consent and when they reach the cut off score of 21, each participant will be given consent to 
sign by themselves at that time. MMSE will be administrated by the primary investigator who is 
a licensed PT who will be trained to administer this test. Participants will be scheduled to do data 
collection on the day they receive their custom double adjustable AFO at Baylor Institute for 
Rehabilitation, Frisco location. 
 
Instrumentation/Measurements 
a) Gait endurance will be measured using the Six Minute Walk Test (6MWT). 
Participants will be asked to ambulate as far as possible in 6 minutes at a self-selected walking 
velocity through a well-lit indoor corridor.  Participants will be informed when half of the time is 
over, otherwise no verbal cueing or encouragement will be provided.  A gait belt will be used to 
ensure patient safety. If the participant needs to sit during the testing, that will be allowed. 

 
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However the timer will not be stopped for sitting rest breaks. The primary investigator will walk 
beside the patient, without influencing the speed of ambulation to ensure safety. The distance 
ambulated during the six minutes will be measured in feet using a measuring wheel and then 
converted to meters for data analysis.  
b) Gait Symmetry will be measured using the temporospatial measurements from the 
GAITRiteTM (CIR systems, Havertown, PA, USA) computerized gait analysis system. The 
GAITRite walking system used in this study is a 16 feet long x 3 feet wide portable walkway 
with embedded pressure sensors at 1.27 cm intervals along the length of the walkway. As the 
participant ambulates on the walkway, the pressure of the foot activates the sensors that record 
the person’s steps. The data will be sampled at 1000 Hz. These measurements are then sent to a 
computer program that analyzes the specified temporal spatial parameters using the algorithm 
built into the special software.  This data can be saved and exported to Microsoft Excel where the 
data can be further analyzed (GAITRite electronic walkway technical reference, revision L. 
2013.)  Step symmetry will be calculated using the ratio of the affected step length to the 
unaffected step length during self-selected velocity walk and fast paced velocity walk, with 
perfect symmetry defined as 1.0.  
c) Gait velocity in cm/sec will also be assessed using the temporospatial measurements of 
the self-selected pace walk and fast paced walk from the GAITRiteTM computerized gait analysis 
system.  
Procedures: 
All measurements will be obtained from each participant during three testing sessions and 
by only one researcher to avoid inter tester reliability issues. On the first measurement day, 
participants receive their custom DA AFO. The primary investigator will collect demographic 

 
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data including age, height, weight, leg length measurements on each side, and Fugl-Meyer 
Lower Extremity Assessment of sensorimotor function. Then the gait outcomes will be measured 
using one of the two AFO conditions in random order. Two possible orders will be written on 
piece of paper and an equal number of possible order selections will be put in a hat. The 
participant will select the order of AFO condition by drawing out of a hat. Randomization 
without replacement will be used. Once the order of AFO wearing has been determined, data will 
be collected in the randomly selected order. Participants will be allowed to use any type of 
assistive device of their choice, but the same device will be used for all conditions. 
First, the 6MWT will be administered with the participant wearing the first randomized 
AFO. Participants will be asked to ambulate as far as possible in 6 minutes at a self-selected 
walking velocity through a well-lit indoor corridor. A five minute seated resting will be provided 
before the next measurement is taken. Next, gait symmetry and gait velocity measurements will 
be obtained using the GAITRite system. Participants will be given a practice trial walk prior to 
beginning of the testing. Participants will be asked to walk at their comfortable self-selected 
walking velocity along the walkway. They will begin walking three meters from the start of the 
walkway and will stop walking two meters past the end of the walkway. The beginning and end 
of the walking area will be marked with red tape for visibility. The verbal instruction will be 
“Please walk from this red line to that red line at your comfortable speed safely”. A second 
personnel will be walking close to the participant outside of the walkway to ensure safety. After 
a five minute sitting break, participant will be asked to walk as fast as they can safely. The verbal 
instruction will be “Please walk from this red line to that red line as fast as you can safely”. The 
GAITRite system will be able to capture both gait symmetry and gait velocity measurements 
with the same walk. Three trials will be performed of the self-selected velocity walk and fast 

 
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paced velocity walk. The calculated mean of the three trials will be used for data analysis. After 
a 10 minute seated rest break, the second AFO condition will be used and measurements will be 
repeated in the same order described above. 
To assess the effects of practice on the gait measures, AFO’s will be randomized for 
practice. Participants will be randomized for which AFO they will wear first (the PLS or the DA 
AFO), by drawing out of a hat. Again randomization without replacement technique will be 
used. Then the participant will be provided with the selected type of AFO to practice with for the 
following week using a prescribed wearing schedule. At the end of the one-week practice time, 
the primary investigator will obtain the same measurements obtained at baseline with the 
participant wearing the type of AFO that was used to practice the week before. The same testing 
conditions and order of testing that were used at baseline will be employed. Once measurements 
are completed, the participant will be provided with the second type of AFO and will be asked to 
wear for one week using the same prescribed wearing schedule as before. Final measurements 
will be taken after completion of the one-week practice using the second type of AFO with the 
same testing conditions and orders. At the conclusion of testing each participant will be asked 
which AFO they will prefer to use for their daily ambulatory needs for descriptive analysis. All 
data collected will be de-identified and stored in the Primary Investigator’s secure personal 
computer. Any documents used such as  Participant information sheet will be securely locked in 
a cabinet at Texas Woman’s University where only the Primary investigator will have access. 
Data Analysis  
The following statistics will be calculated using SPSS for Windows. Descriptive statistics 
will be calculated for all demographic data including age, height, weight, time since onset Fugl 
Meyer lower extremity assessment score and AFO preference.  

 
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Differences in gait endurance will be analyzed using a 2x2 repeated measures ANOVA 
Differences in gait symmetry, and gait velocity between the two AFO conditions and two 
practice conditions will be analyzed using two separate 2x2 repeated measures MANOVA. If 
assumption of sphericity is not met, Greenhouse-Geisser statistic will be used. An alpha level of 
.05 will be used to determine significance of differences, with a Bonferroni correction applied as 
needed to protect against Type I error. 
Funding: This study is funded in part by Texas Physical Therapy Foundation. The grant 
received will allow the researchers to provide each participant a PLS AFO (cost $40) free of 
charge at the beginning of the study and $80 to compensate for their time, at the completion of 
the study. 
 
References 
Bijleveld-Uitman, M., van, d. P., & Kwakkel, G. (2013). Is gait speed or walking distance a 
better predictor for community walking after stroke? Journal of Rehabilitation Medicine, 
45(6), 535-540.  
Bourland, E. L. R., Neville, M. A., & Pickens, N. D. (2011). Loss, gain, and the reframing of 
perspectives in long-term stroke survivors: A dynamic experience of quality of life. Topics 
in Stroke Rehabilitation, 18(5), 437-449.  
Carse, B., Bowers, R., Meadows, B. C., & Rowe, P. (2014). The immediate effects of fitting and 
tuning solid ankle-foot orthoses in early stroke rehabilitation. Prosthetics and Orthotics 
InternationaL.1-9. 
de Sèze, M., Bonhomme, C., Daviet, J., Burguete, E., Machat, H., Rousseaux, M., & Mazaux, J. 
M. (2011). Effect of early compensation of distal motor deficiency by the chignon ankle-
foot orthosis on gait in hemiplegic patients: A randomized pilot study. Clinical 
Rehabilitation, 25 (11) 989-998. 
Eng, J. J., Pang, M. Y. C., & Ashe, M. C. (2008). Balance, falls, and bone health: Role of 
exercise in reducing fracture risk after stroke. Journal of Rehabilitation Research & 
Development, 45(2), 297-313.  

 
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Everaert, D. G., Stein, R. B., Abrams, G. M., Dromerick, A. W., Francisco, G. E., Hafner, B. J., . 
. . Kufta, C. V. (2013). Effect of a foot-drop stimulator and ankle-foot orthosis on walking 
performance after stroke: A multicenter randomized controlled trial. Neurorehabilitation 
and Neural Repair, 27(7), 579-591.  
Executive summary: Heart disease and stroke statistics--2012 update. (2012). Circulation, 
125(1), 188-197.  
GAITRite electronic walkway technical reference, revision L. (2013.). (No. WI-02-15).CIR 
Systems Inc. (GAITRite technical manual) 
Harris, J. E., Eng, J. J., Marigold, D. S., Tokuno, C. D., & Louis, C. L. (2005). Relationship of 
balance and mobility to fall incidence in people with chronic stroke. Physical Therapy, 
85(2), 150-158.  
Hesse, S. (2003). Rehabilitation of gait after stroke: Evaluation, principles of therapy, novel 
treatment approaches, and assistive devices. Topics in Geriatric Rehabilitation, 19(2), 109-
126.  
Hyun, C. W., Kim, B. R., Han, E. Y., & Kim, S. M. (2014). Using an ankle-foot orthosis 
improves aerobic capacity in subacute hemiparetic stroke patients. PM & R: The Journal of 
Injury, Function, and Rehabilitation, 7(3):264-9. 
Jørgensen, H.S., Nakayama, H., Raaschou, H. O., & Olsen, T. S. (1995). Recovery of walking 
function in stroke patients: The Copenhagen stroke study. Archives of Physical Medicine 
and Rehabilitation, 76(1), 27-32.  
Kwakkel, G., Kollen, B., & Lindeman, E. (2004). Understanding the pattern of functional 
recovery after stroke: Facts and theories. Restorative Neurology & Neuroscience, 22(3-5), 
281-299.  
Levin, M. F., Kleim, J. A., & Wolf, S. L. (2009). What do motor "recovery" and "compensation" 
mean in patients following stroke? Neurorehabilitation and Neural Repair, 23(4), 313-319.  
Lord, S. E., McPherson, K., McNaughton, H. K., Rochester, L., & Weatherall, M. (2004). 
Community ambulation after stroke: How important and obtainable is it and what measures 
appear predictive? Archives of Physical Medicine and Rehabilitation, 85(2), 234-239.  
McCain, K. J., Smith, P. S., & Querry, R. (2012). Ankle-foot orthosis selection to facilitate gait 
recovery in adults after stroke: A case series. Journal of Prosthetics and Orthotics. 24 (3), 
111-121. 
Pound, P., Gompertz, P., & Ebrahim, S. (1998). A patient-centred study of the consequences of 
stroke. Clinical Rehabilitation, 12(4), 338-347.  

 
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Rao, N., Chaudhuri, G., Hasso, D., D'Souza, K., Wening, J., Carlson, C., & Aruin, A. S. (2008). 
Gait assessment during the initial fitting of an ankle foot orthosis in individuals with stroke. 
Disability and Rehabilitation.Assistive Technology, 3(4), 201-207.  
Rosa, M. C., Marques, A., Demain, S., & Metcalf, C. D. (2014). Fast gait speed and self-
perceived balance as valid predictors and discriminators of independent community walking 
at 6 months post-stroke - a preliminary study. Disability and Rehabilitation, 37(2), 129-134.  
Rosén, E., Sunnerhagen, K., & Kreuter, M. (2005). Fear of falling, balance, and gait velocity in 
patients with stroke. Physiotherapy Theory & Practice, 21(2), 113-120.  
Schmid, A. A., & Rittman, M. (2009). Consequences of poststroke falls: Activity limitation, 
increased dependence, and the development of fear of falling. The American Journal of 
Occupational Therapy: Official Publication of the American Occupational Therapy 
Association, 63(3), 310-316.  
Simons, C., van Asseldonk, E., H, Geurts, A., & Buurke, J. H. (2009). Ankle-foot orthoses in 
stroke: Effects on functional balance, weight-bearing asymmetry and the contribution of 
each lower limb to balance control. Clinical Biomechanics, 24(9), 769-775.  
Slijper, A., Danielsson, A., & Willén, C. (2012). Ambulatory function and perception of 
confidence in persons with stroke with a custom-made hinged versus a standard ankle foot 
orthosis. Rehabilitation Research & Practice,1-6.  
Tyson, S. F., Sadeghi-Demneh, E., & Nester, C. J. (2013). A systematic review and meta-
analysis of the effect of an ankle-foot orthosis on gait biomechanics after stroke. Clinical 
Rehabilitation, 27(10), 879-891.  
Tyson, S. F., & Kent, R. M. (2013). Effects of an ankle-foot orthosis on balance and walking 
after stroke: A systematic review and pooled meta-analysis. Archives of Physical Medicine 
and Rehabilitation, 94(7), 1377-1385. 
Watanabe, Y. (2005). Fear of falling among stroke survivors after discharge from inpatient 
rehabilitation. International Journal of Rehabilitation Research, 28(2), 149-152.