The ANZCTR website will be unavailable from 1pm until 3pm (AEDT) on Wednesday the 30th of October for website maintenance. Please be sure to log out of the system in order to avoid any loss of data.

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
ACTRN12624001175561
Ethics application status
Approved
Date submitted
13/09/2024
Date registered
25/09/2024
Date last updated
25/09/2024
Date data sharing statement initially provided
25/09/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
The effect of personalised 3D printed metamaterial insoles in combination with a prefabricated offloading device for the reduction of plantar pressure in healthy individuals
Scientific title
The effect of personalised 3D printed metamaterial insoles in combination with a prefabricated offloading device for the reduction of plantar pressure in healthy individuals
Secondary ID [1] 312521 0
Nil Known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Diabetes-related foot ulceration 334392 0
Peripheral neuropathy 334626 0
Condition category
Condition code
Metabolic and Endocrine 331032 331032 0 0
Diabetes
Neurological 331758 331758 0 0
Other neurological disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This is a within-subjects repeated measures cross-over study design evaluating the influence that a personalised 3D printed 'metamaterial' insole may have on changing plantar pressures in conjunction with an ankle-high offloading device. In current practice, treatment for forefoot diabetes-related foot ulceration frequently includes the use of a prefabricated ankle-high offloading device. This study evaluates whether the efficacy of this treatment is changed through use of functionally graded 3D printed insoles that have materials stiffness personalised according plantar pressure.

This study includes several arms and intends to evaluate the effect of data-driven insole design algorithms. As a cross-over study, each participant will experience each intervention and control arm.

Participants will be invited to attend two appointments. Each appointment is anticipated to take approximately 60 minutes.

At an initial appointment, following screening for inclusion/exclusion criteria, plantar pressures will be measured barefoot and when wearing an ankle-high offloading device worn on the right foot. This plantar pressure data will be used to design insoles using automated algorithms. Specifically, the plantar pressure will be used to define the stiffness of the metamaterial across the insole.

This study has four intervention arms and three control arms- for each intervention arm, different algorithm parameters will be used to define the stiffness of the metamaterial insole. Prior engineering work has benchmarked the stiffness of the metamaterial to that of materials that are commonly used in insole and footwear manufacture.

Intervention Arm 1: will use algorithm parameters that will define a relatively soft flat insole, that has compressive mechanical properties similar to Plastazote and Poron.
Intervention Arm 2: will use algorithm parameters that will define a relatively hard flat insole, that has compressive mechanical properties similar to low- to medium-density Ethylene-Vinyl Acetate (EVA)
Intervention Arm 3: will use algorithm parameters that will define a flat insole with hardness between that of Arm 1 and 2. It will have compressive mechanical properties similar to Plastazote, Poron, and low-density EVA.
Intervention Arm 4: will create an insole contoured to the shape of the participants plantar foot, and apply a randomly selected algorithm from the above to set the stiffness of the insole.

Following the initial appointment, each of the interventions and control insoles will be designed and fabricated for the individual. The second appointment is anticipated to occur 2-4 weeks following the initial appointment.

At the second appointment, each of the intervention and control insoles will be fit to a prefabricated ankle-high offloading device in a randomised order. The participant will be blinded to the difference between the different insole conditions. Primary outcome measures (plantar pressure in device during gait) will be recorded after a brief period of acclimatisation.(at least 2 minutes). The participant will walk straight for approximately 10m at a self-selected speed while data is recorded to provide at least 12 steps of data for the foot. Walking speed during the trial will not be controlled, but will be calculated from the time it takes the person to walk the predefined distance. Three trials will be completed for each study arm. There will be an washout and rest period between study arms of at least 3 minutes.

When trialing the interventions, the participant will wear the offloading device with trial insole on the right foot, and their own shoe on the contralateral foot.

As an immediate effects study design, insoles will not be worn for an extended period nor taken by the participants, and no assessment of adherence will be performed. Should any intervention be discontinued prior to data collection (e.g. due to discomfort reported by participant), this will be reported.

Each intervention will be designed, manufactured, and fit by a podiatrist at a university research facility.
Intervention code [1] 329039 0
Treatment: Devices
Comparator / control treatment
Three control arms will be used in this study:
Control Arm 1 (Reference comparator): Prefabricated ankle high offloading device only - This represents the most frequent practice that is currently used clinically. The offloading device comes with a flat prefabricated flat insole.
Control Arm 2: Prefabricated ankle-high offloading device with an insole that has been fabricated using standard manufacture means (i.e. CNC milled Ethylene-Vinyl Acetate) to contour the plantar surface of the foot but without personalisation of mechanical properties of the insole. This represents a frequent current practice.
Control Arm 3: Barefoot - Many people with diabetes-related foot ulceration continue to walk barefoot.
Control group
Active

Outcomes
Primary outcome [1] 338841 0
Peak plantar pressure
Timepoint [1] 338841 0
Immediate effects following a brief acclimatisation period (at least 2 minutes) wearing the insole condition.
Secondary outcome [1] 437659 0
Pressure-time integral.
Timepoint [1] 437659 0
Immediate effects following a brief acclimatisation period (at least 2 minutes) wearing the insole condition.
Secondary outcome [2] 437660 0
Comfort in each device.
Timepoint [2] 437660 0
Immediately following trials for each insole condition.
Secondary outcome [3] 437661 0
Ranking of comfort of all devices.
Timepoint [3] 437661 0
After trialling all intervention/control conditions.
Secondary outcome [4] 437671 0
Average plantar pressure during stance.
Timepoint [4] 437671 0
Immediate effects following a brief acclimatisation period (at least 2 minutes) wearing the insole condition.

Eligibility
Key inclusion criteria
Able to walk for 10 minutes without use of assistive devices (e.g. walking frame, walking stick).
Available to attend a follow up appointment 2-4 weeks after the initial appointment.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Evidence of peripheral arterial disease.
Loss of peripheral protective sensation.
Current or history of previous foot ulceration, Charcot neuroarthropathy, previous amputation of foot (at any level).
Previous amputation to lower limb.
History of falls in previous 12 months.
Current or recent (4 weeks) self-reported foot or leg pain.

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 - All participants will experience all intervention arms in this immediate-effects crossover tiral.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The order in which participants will trial each intervention orthosis will be randomised through computer sequence generation.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
A sample size calculation indicates we need to recruit 14 participants based off a clinically meaningful difference in peak pressure of 100 kPa between conditions with a standard deviation of 100 kPa.. Alpha was set at 0.05, with 80 percent power. This indicated a required sample size of 11 participants. Accounting for approximately 20% attrition prior to attending the second measurement session, this would require 14 participants to be recruited.

Primary outcomes:
Repeated measures ANOVAs will be used to test the differences between intervention and control arms on plantar pressure outcomes with Bonferroni post-hoc testing used for multiple pairwise comparisons.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
QLD

Funding & Sponsors
Funding source category [1] 316946 0
Government body
Name [1] 316946 0
National Health and Medical Research Council
Country [1] 316946 0
Australia
Funding source category [2] 316957 0
Charities/Societies/Foundations
Name [2] 316957 0
Urgo Foundation
Country [2] 316957 0
France
Primary sponsor type
University
Name
Queensland University of Technology
Address
Country
Australia
Secondary sponsor category [1] 319192 0
None
Name [1] 319192 0
Address [1] 319192 0
Country [1] 319192 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 315697 0
Queensland University of Technology University Human Research Ethics Committee
Ethics committee address [1] 315697 0
Ethics committee country [1] 315697 0
Australia
Date submitted for ethics approval [1] 315697 0
20/11/2023
Approval date [1] 315697 0
30/08/2024
Ethics approval number [1] 315697 0
LR 2024-6075-20445

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 135538 0
A/Prof David Holmes
Address 135538 0
O Block room O711, Queensland University of Technology Gardens Point, George St, Brisbane, 4000
Country 135538 0
Australia
Phone 135538 0
+61 0731386887
Fax 135538 0
Email 135538 0
Contact person for public queries
Name 135539 0
Alex Terrill
Address 135539 0
Biofabrication and Tissue Morphology Group, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, QLD, 4059
Country 135539 0
Australia
Phone 135539 0
+61 0731388224
Fax 135539 0
Email 135539 0
Contact person for scientific queries
Name 135540 0
Alex Terrill
Address 135540 0
Biofabrication and Tissue Morphology Group, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, QLD, 4059
Country 135540 0
Australia
Phone 135540 0
+61 0731388224
Fax 135540 0
Email 135540 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Deidentified individual participant data that forms the basis of publications arising from the study.
When will data be available (start and end dates)?
Immediately following publication for 5 years.
Available to whom?
Data will be made available on QUT's publically accessible data repository.
Available for what types of analyses?
Any purpose.
How or where can data be obtained?
Data will be made available on QUT's publically accessible data repository, via https://data.researchdatafinder.qut.edu.au.


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.