Trial Review

Technical difficulties have been reported by some users of the search function and is being investigated by technical staff. Thank you for your patience and apologies for any inconvenience caused.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12622000586718
Ethics application status
Approved
Date submitted
7/04/2022
Date registered
20/04/2022
Date last updated
17/05/2022
Date data sharing statement initially provided
20/04/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
The effect of positive pressure treadmill training in young people with cerebral palsy
Scientific title
The effect of positive pressure treadmill training on muscle synergies in young people with cerebral palsy
Secondary ID [1] 306841 0
University of Auckland study ID: 11871
Universal Trial Number (UTN)
U1111-1266-9640
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Cerebral palsy 325934 0
Condition category
Condition code
Neurological 323246 323246 0 0
Other neurological disorders
Physical Medicine / Rehabilitation 323306 323306 0 0
Physiotherapy

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
1. Name
The effect of positive pressure treadmill training in young people with cerebral palsy.

2. Why:
Any movement requires the coordination of multiple muscles at the same time. Advances in the techniques to analyse muscle patterns lead to the theories of modular control of the central nervous system—and the modules are called muscle synergies (MSs) (d'Avella et al., 2003).

Children with Cerebral Palsy (CP) recruit fewer synergies during walking. Previously, we demonstrated the possibility to upregulate the number of MSs in a neurological population (Runnalls et al., 2019). This upregulation or higher number of MSs was achieved by providing body weight support (BWS). Moreover, similarly to our results, EMG activity is modulated using BWS (Colby et al., 1999). Since fewer or altered recruitment of MSs is proposed as the underlying mechanism of abnormal motor behaviour after neurological disorders (Cheung et al., 2009), overall, the effect of neural modulation of BWS over MSs could lead to new strategies for rehabilitation.

Treadmill protocols have been shown to increase walking speed, endurance and improved gait kinematics (Provost et al., 2007) in children with different types and severity of CP (Chrysagis et al., 2012). Similarly, in CP populations, training with positive pressure treadmills has shown to be a significant improvement compared to regular physical therapy treatments for balance, force (Dadashi et al., 2018) and gait kinematics (Azizi et al., 2017). However, there is no agreement on protocols for gait training, and parameters depend on clinical principles and observations rather than objective parameters. Treadmill gait training is based on the principle of repetitive motor learning, promoting the formation of clustered dendritic spines in the motor cortex, which are necessary for long-lasting learning (Fu et al., 2012). Motor learning could be translated into acquiring new synergies (Berger et al., 2013) or improved temporal tuning (Dominici et al., 2011). Training with higher motor complexity could lead to better long-lasting motor outcomes.

3. What:

Materials:
Treadmill: We will use a positive pressure treadmill for gait training .

Electromyography: Sixteen electromyography (EMG) sensors would be placed bilaterally on both legs. EMG data will be used to extract muscle synergies.

Kinematics: 27 reflective markers will be used to calculate body kinematics during overground walking.

Accelerometry: Seven accelerometers will be placed on the participant’s lower limb segments to calculate the lower kinematics.

Design:
The study consists of a randomized controlled trial, with an intervention of gait training under two different arms 1) high Body Weight Support (BWS) and 2) minimal BWS on a positive pressure treadmill, with a cross-over design where participants will switch protocols after two weeks from the end of the randomly allocated first training protocol.

The participants will attend their participation in the Health & Rehabilitation Clinic of the University of Auckland. Two types of sessions during the study; two initial assessment sessions, at least eight training sessions and two post-training assessment sessions.

The participants then will train by walking on an anti-gravity treadmill under the two study arms: A) low weight support and B) high weight support. Low support will consist of training with minimal weight support to aid the participants’ balance. The high weight support, as the intervention, will be adjusted individually for each participant based on the results of the treadmill assessment. More specifically, participants will train at the weight support level where they exhibit an increase in the number of synergies; this is expected to be around 50% of the participant’s own body weight. The weight support is provided by positive pressure through an inflatable bag. For both training modalities, participants will walk at their own self-selected speed and will be encouraged to increase it if possible at the beginning of every session.

Each training protocol will last four weeks, 2-3 times a week (according to participant's availability) and one hour each session. Each visit is expected to last an average of 1-1.5 hours. Training will be done on a one-on-one basis, and session attendance will be recorded on RedCap. As a cross-over design, participants will have a wash-out period of two weeks between the trainings.

All the procedures will be executed or under the supervision of physiotherapists and qualified research and clinical staff of the University of Auckland. To encourage participation and fidelity, participants will be reimbursed for their participation transport expenses.
Intervention code [1] 323309 0
Rehabilitation
Intervention code [2] 323312 0
Treatment: Devices
Comparator / control treatment
Low support will consist of training with minimal weight support to aid the participants' balance. The dosage is expected to be five percent of the participant's own body weight.
Control group
Active

Outcomes
Primary outcome [1] 330993 0
The number of muscle synergies, extracted from the concatenated information of the electromyography sensors while walking overground.
Timepoint [1] 330993 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Primary outcome [2] 331043 0
The number of muscle synergies, extracted from the concatenated information of the electromyography sensors while on a treadmill at different weight support levels.
Timepoint [2] 331043 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [1] 408430 0
Gross Motor Function Measure score.
Timepoint [1] 408430 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [2] 408431 0
Joint angle kinematics of the lower limbs during overground walking, measured with infrared cameras and reflective markers.
Timepoint [2] 408431 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [3] 408432 0
Distance walked during 6-minute walk test
Timepoint [3] 408432 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [4] 408433 0
Electromyographic activity in time and amplitude of lower limb muscles while walking overground.
Timepoint [4] 408433 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [5] 408463 0
Accelerometry data from three axes inertial sensors during overground walking.
Timepoint [5] 408463 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [6] 408572 0
Electromyographic activity in time and amplitude of lower limb muscles while walking on a treadmill at different weight support levels
Timepoint [6] 408572 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [7] 408573 0
Accelerometry data from three axes inertial sensors during walking on a treadmill at different weight support levels.
Timepoint [7] 408573 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.
Secondary outcome [8] 408574 0
Functional Mobility Scale from clinical assessment.
Timepoint [8] 408574 0
Baseline - preintervention
4 weeks - after the first training
6 weeks - prior second training
10 weeks- after second training.

Eligibility
Key inclusion criteria
We would recruit 30 children with a diagnosis of CP between 8 - 15 years old
Inclusion criteria :
- able to understand simple instructions
- above 1.4 meters tall (treadmill constraint).
- Categorised as I, II or III on the Gross Motor Function Classification System.
Minimum age
8 Years
Maximum age
15 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion criteria:
- Undergoing lower limb/gait focused physical therapy, or if in the six months before the trial start.
- Had have undergone lower limb surgery, botulinum toxin injections, or serial casting, or if they have a concurrent medical condition, such as uncontrolled epilepsy, that will limit their ability to participate in the training protocol.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A simple randomization model will be generated in the RedCap.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
The sample size was determined over a statistical power of 80% with a priori analysis, using the mean difference between two dependent means t-tests given a medium effect size of 0.4. Sample size calculation resulted in a sample of 29 participants and rounded up to 30. Calculations were made with G-power.

Muscle synergies will be extracted by using non-negative matrix factorization. The number of synergies will be determined with Variance accounted for, where a number of synergies are considered significant when the variance explained by the reconstructed signal explains 90% or more of the variance of the original matrix. Synergies will be clustered across individuals based on k-medoid analysis. Cross-correlation and scalar product analysis will validate the similarity of synergies within a cluster. Paired statistical tests will finally determine if any differences in the number of synergies in time.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
31/05/2022
Actual
Date of last participant enrolment
Anticipated
31/01/2023
Actual
Date of last data collection
Anticipated
11/04/2023
Actual
Sample size
Target
30
Accrual to date
Final
Recruitment outside Australia
Country [1] 24713 0
New Zealand
State/province [1] 24713 0
Auckland

Funding & Sponsors
Funding source category [1] 311169 0
Charities/Societies/Foundations
Name [1] 311169 0
Friedlander Foundation
Country [1] 311169 0
New Zealand
Primary sponsor type
University
Name
The University of Auckland
Address
20 Symonds Street
Auckland 1010
New Zealand
Country
New Zealand
Secondary sponsor category [1] 312545 0
None
Name [1] 312545 0
Address [1] 312545 0
Country [1] 312545 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 310699 0
Southern Health and Disability Ethics Committees
Ethics committee address [1] 310699 0
133 Molesworth Street
Thorndon
Wellington 6011
Ethics committee country [1] 310699 0
New Zealand
Date submitted for ethics approval [1] 310699 0
24/03/2022
Approval date [1] 310699 0
28/04/2022
Ethics approval number [1] 310699 0
12531

Summary
Brief summary
Aim
Determine the effect and difference between two gait training protocols using a positive pressure treadmill over young people with cerebral palsy.

Secondary aims
- Determine the difference before and after each gait training protocol.

- Determine the neuromuscular, gait and functional outcomes produced by different levels of BWS using a positive pressure treadmill.

Hypotheses
One of the goals of rehabilitation protocols is to enhance motor performance, considering the importance of repetitive behaviours and variability for motor learning; a positive pressure treadmill with a higher BWS seems likely to generate better outcomes. Higher levels of BWS can modulate synergies, allowing the emergence of new muscle coordination patterns (muscle synergies). On the one hand, a higher BWS allows higher motor variability, allowing these new coordination patterns to emerge. On the other hand, the repetitive execution of new synergies by maintaining the same BWS through the training, instead of decreasing or low BWS protocol, could enhance and further preserve the newly recruited synergies.

- Comparing the initial data from overground walking and throughout the training, the number of synergies is expected to increase for the CP population with a higher BWS. Additionally, training with a higher BWS is expected to further improve walking speed, endurance and gait kinematics compared with a minimal BWS protocol.

- We expect a modulation in the number or structure of muscle synergies, with an increase in the number of synergies in the higher BWS protocol, as seen in our previous study (Runnalls et al., 2019). Previously, we demonstrated the possibility of upregulating synergies by providing WS to the upper extremity, suggesting more complex motor behaviours. If a positive change in the number of synergies is found, the individual value of BWS modulating synergies would be used as a threshold for the intervention study.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 118558 0
Dr Pablo Ortega-Auriol
Address 118558 0
Department of Exercise Sciences
The University of Auckland
Newmarket Campus, Building 907
Suiter Street
Newmarket,
Auckland 1023
Country 118558 0
New Zealand
Phone 118558 0
+64 9 9236844
Fax 118558 0
Email 118558 0
p.ortegaauriol@auckland.ac.nz
Contact person for public queries
Name 118559 0
Dr Pablo Ortega-Auriol
Address 118559 0
Department of Exercise Sciences
The University of Auckland
Newmarket Campus, Building 907
Suiter Street
Newmarket
Auckland 1023
Country 118559 0
New Zealand
Phone 118559 0
+64 9 9236844
Fax 118559 0
Email 118559 0
p.ortegaauriol@auckland.ac.nz
Contact person for scientific queries
Name 118560 0
Dr Pablo Ortega-Auriol
Address 118560 0
Department of Exercise Sciences
The University of Auckland
Newmarket Campus, Building 907
Suiter Street
Newmarket 1023
Auckland 1023
Country 118560 0
New Zealand
Phone 118560 0
+64 9 9236844
Fax 118560 0
Email 118560 0
p.ortegaauriol@auckland.ac.nz

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Our data protocol considers the possibility to share de-identified data for related research, but no public data will be available. The main reason is data protection for participants and Maori data sovereignty.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.