Gait Training Combined With Behavioral Strategies for People With Stroke

This proposal seeks to investigate the effect of gait training combined with behavioral strategies on long-term retention of improvements on gait parameters and use of the affected lower-extremity in real-world situations.

Aim 1: To assess transfer and long-term retention of walking and balance skills after robotic treadmill gait training combined with the TP. A total of 24 participants with chronic stoke will be randomly allocated to either treadmill training combined with the TP (TT+TP) or usual TT with an educational approach. The 8-week intervention will consist of three weekly sessions of 1 hour of TT. The experimental group will also receive the TP for 30 minutes and the control group will receive a manual with exercises to be performed at home. The primary outcome is the change in Lower-Extremity Motor Activity Log. Also, change in walking speed, endurance, functional strength and use of the affected LE will be assessed at 3- and 6-months after the intervention.

Aim 2: To understand participants' acceptability and perceptions of the TP as a tool to enhance transfer of skills to real-world situations. A qualitative approach will be used for evaluating the acceptability of the TT + TP protocol. Individual interviews will be conducted with all participants to assess their opinion about TP, particularly, their perceived influence of the TP on real-life situations.

Aim 3: To examine the feasibility of body weight support treadmill training combined with behavioral strategies to improve walking and balance after stroke. Compliance with the intervention will be measured as the number of sessions attended and number of activities performed outside the clinical setting. Also, the relationship between the outcome changes after the intervention and the participants' perceptions will be explored.

The hypothesis is that the use of the TP will promote long-term retention of the positive changes in walking and balance and also changes in real-world situations. This pilot study will lead to future studies with larger samples in order to compare the effect of body weight support treadmill training combined with the TP. The long-term goal is to provide a systematic combination of strategies to improve gait and mobility after stroke that can be implemented in the clinical setting.

In this study our goal is to combine gait training with a robotic treadmill and the TP. The TP is adapted from our previous work with Lower-Extremity Constraint-Induced Movement Therapy. The effect of the combined gait training will on real-world use of the affected lower extremity, walking speed, endurance, functional strength will be tested as well as the effect of the TP on long-term retention. Furthermore the combined TP + treadmill training will be meaningful to the patient.

1. Participants: sampling and selection criteria Participants will be recruited from a list of patients that have been discharged from the Spain Rehabilitation Center at University of Alabama at Birmingham (UAB). Participants will be recruited from a registry of individuals who have had a stroke and whom are interested in research managed by the Department of Neurology at UAB. The inclusion criteria is as follows: (1) 18 years of age or older; (2) at least 6 months post stroke; (3) present lower extremity motor impairment secondary to stroke, (4) able to walk at least 10 feet with or without personal assistance; (5) discharged from rehabilitation. Participants will be excluded if present uncontrolled clinical conditions, weight > 400lb because this is limit supported by the KineAssist, other neurologic conditions, a Mini-Mental State Examination score (MMSE) <24, inability to provide the informed consent, and insufficient language skills to answer the screening, assessments and interview questions. Participants will be first contacted by phone and the study will be fully explained, if the participant is interested the first screening interview will be conducted. During this first screening the inclusion criteria and the availability of the participants will be checked. After assuring the inclusion criteria have been met, a more thorough in-person screening examination will be scheduled in order to assess participants' cognitive and motor functions. All participants will be asked to voluntarily provide informed consent. A total of 24 people with chronic stroke will be selected and will be randomly allocated to TT+TP (N=12) or TT group (N=12). Sample calculation was performed using standard deviation and effect size of the LE-MAL which was obtained from a previous study conducted by the PI.20 This proposal is 90.9% powered to detect a significant difference between study arms of 1.55 improvement on the LE-MAL.
2. Intervention All participants will receive the same robotic treadmill training. The training conducted on the robotic treadmill device will be based on different constructs of walking and balance, including standing, stepping, propulsion, speed, strength, and endurance. The KineAssistTM (KA) robotic device will be used for targeted training of participants. The KA uses a patented force-sensing, pelvic support mechanism to sense the user's intended walking speed and direction to drive a moving surface, thus allowing a person to move at their own intended walking speed and pace. The device is sensitive enough to allow sudden starting and stopping movements, so that balance tasks and responses to sudden disturbances can be accommodated. This system is uniquely different compared to a treadmill, which only moves at a fixed speed and can only allow repetitive stepping protocols. The robotic system that allows individuals to move at self-driven speeds against challenging conditions in order to implement a combinatorial approach to assessment and intervention. The transfer package element of the body weight support treadmill training, was modified accordingly in order to fit the gait training intervention. The TP procedures will be administered as described below. On the first day of treatment, participants will be asked to sign the behavioral contract (BC). The purpose of the BC is to: (1) achieve safety while engaging in improved use of the LEs, (2) increase use of the more-affected LEs in functional activities whenever possible, and (3) increase use of both LEs in a more coordinated manner. Additionally, the behavioral contract formally engages the patient in actively exploring more ways to use their more-affected LE in their home environment and in adopting a problem-solving approach to accomplish that end. The BC will be worked out with the patient at the end of the first treatment day. Before discussing the contract, therapist will develop in conjunction with the participant a daily activity schedule from the time of awakening in the morning until arrival at the clinic for training on subsequent days, and between sessions.. Also a list of activities to be performed outside the clinical setting, the Home Skill Assignment (HSA), will be developed for each day of the week during the treatment period. The HSA process is a transfer technique designed to encourage use of the more-affected LE during activities of daily living (ADL). The HSA supports and should be in agreement with the behavioral contract. It will be given to the patient as a written set of activities to be accomplished after the end of the treatment session and it has a check-off component. After each activity is accomplished outside the treatment setting the patient checks that item Another component of the TP is the Home Practice after treatment. The purpose of home task practice after the intervention period is to assure continued progress with LE use after the intervention program is completed. With home practice, participants are encouraged to engage in functional skills and fitness activities on a daily basis. These activities will maintain improvements in LE use realized during the LE-CIMT protocol and possibly enhance them. Toward the end of treatment, a written individualized post-treatment home practice program will be developed and given to the patient. The program consists of 7 separate lists, one for each day of the week, repeated weekly. The last TP element is the administration of the Lower-Extremity Motor Activity Log (LE-MAL) during all treatment sessions. A full description of the LE-MAL is provided in the Results/Outcomes section below. The 8-week intervention will consist of three weekly sessions of 1 hour of TT. The experimental group will also receive the TP for 30 minutes and the control group (TT group) will receive a handbook with exercises and stretching techniques. Therapists will ask the participants of this group to pick up at least 2-3 activities and perform them for 30 minutes everyday.
3. Outcomes In order to assess LE physical performance and use, the following primary outcome tools will be used: (1) the primary outcome is the Lower Extremity Motor Activity Log (LE-MAL);20,21 (2) Berg Balance Scale (BBS);22 (3) 10 meters walk test (10MWT);23 and (4) 6 minutes walking test (6MWT).24 The secondary outcomes are: (1) 5 times sit to stand (5TSTS);25 (2) Fear of Falling Avoidance Behavior Questionnaire (FFABQ).36 The LE-MAL is a semi-structured interview, created in the UAB Constraint-Induced Therapy Research Group laboratory, that consists of questions asking the participant the level of assistance, how well her/his performance is, and level of confidence while executing 14 different daily tasks (e.g. walking indoors, climbing stairs) in real world environment.20,41 The LE-MAL investigates the transference of the skills addressed during the treatment to different contexts. The principal investigator of this proposal has used the test extensively and has participated in a reliability and validity study of the LE-MAL which showed that the LE-MAL is a reliable tool in both test-retest results (r=0.93) and internal consistency (Cronbach's alpha = 0.96).

Assessments will be administered during pre-, post-treatment and follow up visits (3 and 6 months after the end of the intervention protocol). Each assessment visit will last approximately 40 minutes. The follow up assessment will provide information regarding long-term retention of results and will serve as the basis for future research. Pre-, post-treatment, and follow up assessments will be compared in order to investigate changes observed compared to the baseline and long term retention of these changes. For this, an analysis of covariance (ANCOVA) will be utilized to analyze the changes among different time points (post-treatment and follow up assessments). Those subjects with complete data will contribute to the analysis. In case of missing data, a last observation carried forward (LOCF) sensitivity analysis will be conducted. In addition, those with incomplete follow-up data will be compared to subjects with complete data to see if the groups differ significantly in baseline characteristics.

Compliance will be described by the percentage of sessions attended and number of activities performed outside the clinical setting. Considering that the participants will receive a list with 10 activities to be performed in the real world (Home Skill assignment), a total of 560 activities will be listed during the intervention. In a previous LE Constraint-induced therapy study, participants performed approximately 85% of the activities. However, this was a shorter intervention (2 weeks) and a lower percentage might be observed in longer protocol as the purposed here. Thus, a minimum of 60% of compliance regarding the list of activities will be expected.

A qualitative strand will be conducted after the conclusion of the treatment. Participants will be interviewed face-to-face to determine perspectives regarding the intervention protocol, especially acceptability. Semi-structured, in-depth interviews will be conducted regarding how time consuming the TP is (outside the clinical setting), potential routine modifications, and potential suggestions. The interviews will be conducted by other researchers who are knowledgeable and skilled in qualitative interviewing and are uninvolved in the delivery of the treatment to avoid influence on participants' responses. The interviews will be audio recorded and transcribed verbatim. The interviewer will follow a script which provides participants with an overview of the interview protocol. The interview questions will include participant's impression about the elements of the TP, the transference of motor skills trained during the gait sessions to other environments, compliance with procedures, and suggestions for modifications. Perceptions regarding the control condition will also be collected using the same procedures.

The qualitative data will be analyzed through thematic analysis procedures in which the main themes collected along the interview will be categorized and reported.27 Two researchers will code the transcripts independently. The themes will be compared and revised by both coders. The themes will be refined if needed, and the final list of themes will be reported in a joint display.