Comparison of a robotic-assisted gait training program with a program of functional gait training for children with cerebral palsy: design and methods of a two group randomized controlled cross-over trial

Background Enhancement of functional ambulation is a key goal of rehabilitation for children with cerebral palsy (CP) who experience gross motor impairment. Physiotherapy (PT) approaches often involve overground and treadmill-based gait training to promote motor learning, typically as free walking or with body-weight support. Robotic-assisted gait training (RAGT), using a device such as the Lokomat®Pro, may permit longer training duration, faster and more variable gait speeds, and support walking pattern guidance more than overground/treadmill training to further capitalize on motor learning principles. Single group pre-/post-test studies have demonstrated an association between RAGT and moderate to large improvements in gross motor skills, gait velocity and endurance. A single published randomized controlled trial (RCT) comparing RAGT to a PT-only intervention showed no difference in gait kinematics. However, gross motor function and walking endurance were not evaluated and conclusions were limited by a large PT group drop-out rate. Methods/design In this two-group cross-over RCT, children are randomly allocated to the RAGT or PT arm (each with twice weekly sessions for eight weeks), with cross-over to the other intervention arm following a six-week break. Both interventions are grounded in motor learning principles with incorporation of individualized mobility-based goals. Sessions are fully operationalized through manualized, menu-based protocols and post-session documentation to enhance internal and external validity. Assessments occur pre/post each intervention arm (four time points total) by an independent assessor. The co-primary outcomes are gross motor functional ability (Gross Motor Function Measure (GMFM-66) and 6-minute walk test), with secondary outcome measures assessing: (a) individualized goals; (b) gait variables and daily walking amounts; and (c) functional abilities, participation and quality of life. Investigators and statisticians are blinded to study group allocation in the analyses, and assessors are blinded to treatment group. The primary analysis will be the pre- to post-test differences (change scores) of the GMFM-66 and 6MWT between RAGT and PT groups. Discussion This study is the first RCT comparing RAGT to an active gait-related PT intervention in paediatric CP that addresses gait-related gross motor, participation and individualized outcomes, and as such, is expected to provide comprehensive information as to the potential role of RAGT in clinical practice. Trial registration ClinicalTrials.gov NCT02196298 Electronic supplementary material The online version of this article (doi:10.1186/s40064-016-3535-0) contains supplementary material, which is available to authorized users.

4. Practice continuous tasks, such as walking, in whole practice rather than part by breaking the skill down into components. Rather, practice the whole skill with a focus on developing specific or challenging elements. Remember to design skill practice in a manner that will transfer to daily tasks.
5. When beginning the treatment arm, give as much verbal and visual feedback as possible. Visual feedback can be provided using mirror and modelling, and physical guidance can be used when needed. Fade feedback as required to increase the challenge and to promote the child's reliance on intrinsic feedback. Draw the child's attention to intrinsic feedback by asking them to describe the feelings in his/her legs, or cueing the child to focus on specific sensations.
6. Provide opportunity for error and success. Encourage the child, and provide information about positive elements and areas to improve in both the performance of the task (i.e. movement quality) and outcome of the task (i.e. did the ball go in the hoop).

PT TRAINING
Any of the intervention areas outlined below can be chosen for a session. The same activities do not need to be done at each session. The length of time spent within each intervention area is at the discretion of the treating PT. The focus is likely a mix of several intervention areas.
Any basic work done on range of motion or stretching should not be part of the session as it is not part of an active motor learning-based program -if needed, take 10 to 15 minutes prior to the session to do this. Please record in the log if this time is added to any of the sessions.
When recording the focus of the intervention area on the PT treatment log sheet (see sample on last page), one or more categories can be used, e.g., exercises on the Bosu ball might be for strength, stability/balance and co-ordination. Each box on the first page of the log sheet should be marked to indicate this. The primary focus should be marked as '1' in the corresponding box, with all secondary categories marked as a '2'. You may change the primary focus of the same activity from session to session (e.g., if using the ball, the primary focus might be strength at one session and stability at the next). This is why it is important to complete the activity log with each session. You and your partner PT might choose to do different activities as well. This is fine as long as they line up with the child's goals, and have a logical link with the activities in the past sessions.

Don't forget:
The time spent in each intervention and the specific details of the session (repetitions, weight, distance) must also be documented on the second page of the PT treatment log. This information is critical to guide you and your partner PT in progressions.

OVERGROUND WALKING PRACTICE
This is done within the context of the session as appropriate to the goal plan.

HOMEWORK
While we do not want you to give the children any additional physiotherapy exercises to work on during this trial, you can encourage them to practice the elements of gait they focused on during the physiotherapy session. Suggest they practice at home each day when they walk, and help them to select an environment in which to practice (i.e. hallway at home). Additionally, the children can be encouraged to do 'mind gym' work, when they spend time thinking about how to walk.