3D Printed Metamaterial Insoles for Diabetes-Related Foot Ulceration

Trial Review

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Registration number

ACTRN12626000508370 Ethics application status

Approved Date submitted

16/04/2026 Date registered

23/04/2026 Date last updated

23/04/2026 Date data sharing statement initially provided

23/04/2026 Type of registration

Prospectively registered
Titles & IDs Public title The effect of personalised 3D printed metamaterial insoles on plantar pressures in adults at risk of diabetes-related foot wounds. Query! Scientific title Evaluation of the effect of 3D printed functionally graded metamaterial insoles on plantar pressures in adults at risk of diabetes-related foot ulceration: A within-subjects crossover study. Query! Additional trial identifiers [1] 316781 0 Nil known Query! Universal Trial Number (UTN) Query! Trial acronym Query! Related trial records This is a follow up study to ACTRN 12625000905460. This previous study evaluated the effects of 3D printed functionally graded metamaterial insoles on plantar pressure in healthy adults. Preliminary findings suggest the effects of the insoles on plantar pressure are comparable to the current standard of care insoles in reducing plantar pressures. This follow-up study will evaluate their effect in the target population for the intervention: people at risk of diabetes-related foot ulceration. Query!
Health condition Health condition(s) studied: Diabetes-related foot ulceration 341425 0 Query! Peripheral neuropathy 341426 0 Query! Condition category Condition code Neurological 337480 337480 0 0 Query! Other neurological disorders Query!

Metabolic and Endocrine 337507 337507 0 0 Query! Diabetes Query!

Intervention/exposure Study type Interventional Query! Description of the intervention or exposure Current Australian and international guidelines recommend the use of medical-grade footwear and personalised insoles to prevent diabetes-related foot ulceration in individuals at risk, particularly those with foot deformities or pre-ulcerative lesions.

This study will evaluate whether functionally graded 3D printed insoles that have material stiffness personalised according to plantar pressure measurements are as effective as the current standard of care in reducing plantar pressures in people at risk of diabetes-related foot ulceration.

This study includes several arms. 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 the issued medical grade trial footwear. This plantar pressure data will be used to design insoles using an automated algorithm. Specifically, the plantar pressure will be used to define the stiffness of the metamaterial across the insole.

This study has two intervention arms and two control arms.
Intervention arm 1 will be a 3D printed metamaterial insole comprising metamaterials of uniform stiffness that approximates low density EVA foam (the current standard of care).

Intervention arm 2 will be a 3D printed metamaterial insole comprising metamaterials with graded stiffness that ranges from low density EVA foam (at hardest) through to Poron (blue medical), a material commonly used as a component of insoles designed to reduce plantar pressures in clinical practice (at softest). The stiffness of the insole will be set based upon the peak plantar pressure at the corresponding part of the foot. Between these thresholds, the stiffness will be interpolated. The design algorithm parameters will define a graduated transition zone, whereby at sites of the foot with low pressures (less than 50 kPa), the insole will have properties approximating low density EVA, and at sites of high pressures (greater than 200 kPa), the insole will have properties approximating Poron (blue medical).

Prior engineering work has benchmarked the stiffness of the metamaterial to that of materials that are commonly used in insole and footwear manufacture (EVA foam and Poron). Following the initial appointment, each of the intervention 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 the standardised medical grade footwear 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 be self-selected for the first trial and measured, to ensure each subsequent trial is within ten percent of this speed. Trials outside of this will be discarded and repeated to ensure walking speed is kept consistent during testing of each condition. Three trials will be completed for each study arm. There will be a washout and rest period between study arms of at least 3 minutes.

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 and the control insole will be designed, manufactured, and fit by a podiatrist at a university research facility. Query! Intervention code [1] 333697 0 Treatment: Devices Query! Description of the comparator or control Two control arms will be used in this study:
Control Arm 1 (Reference comparator): standardised medical grade footwear - This represents footwear that meets current guidelines for use by people at risk of diabetes-related foot ulceration with foot deformity and/or pre-ulcerative lesions.
Control Arm 2: Standardised medical grade footwear and current standard of care personalised insole 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 i.e. with uniform stiffness. This represents a frequent current practice. Query! Control group Active Query!
Outcomes Primary outcome [1] 344988 0 Peak plantar pressure Query! Timepoint [1] 344988 0 Immediate effects following a brief acclimatisation period (at least 2 minutes) wearing the insole condition Query! Secondary outcome [1] 460067 0 Percentage area of foot where peak plantar pressures are reduced by 30% or more or to below 200kPa. Query! Timepoint [1] 460067 0 Immediate effects following a brief acclimatisation period (at least 2 minutes) wearing the insole condition Query! Secondary outcome [2] 460068 0 Pressure-time integral Query! Timepoint [2] 460068 0 Immediate effects following a brief acclimatisation period (at least 2 minutes) wearing the insole condition Query! Secondary outcome [3] 460069 0 Spatiotemporal parameters of gait Query! Timepoint [3] 460069 0 This will be measured for each walking trial in each of the trial conditions. Query! Secondary outcome [4] 460070 0 Comfort in each insole condition Query! Timepoint [4] 460070 0 Immediately following trials for each insole condition. Query!
Eligibility Key inclusion criteria Over 18 years old
Available to attend follow up data collection appointment 2-4 weeks following initial data collection
Able to walk for ten minutes duration without the use of assistive devices (e.g. walking stick or frame)
Diagnosis of diabetes
Have an International Working Group for the Diabetic Foot (IWGDF) risk classification of moderate to high risk with foot deformity or a buildup of hard skin (callous) or a previous history of diabetes related foot ulceration. Query! Minimum age 18 Years Query! Query! Maximum age No limit Query! Query! Sex Both males and females Query! Can healthy volunteers participate? No Query! Key exclusion criteria Under 18 year of age
Unable to walk for ten minutes unassisted
History of foot or lower limb amputation
History of Charcot neuroarthropathy
Active diabetes-related foot ulceration
End-stage renal disease
History of falls in the past 12 months Query!
Study design Purpose of the study Prevention Query! Allocation to intervention Randomised controlled trial Query! 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 trial. Query! 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. Query! Masking / blinding Blinded (masking used) Query! Who is / are masked / blinded? The people receiving the treatment/s

Query! Query! Query! Query! Intervention assignment Crossover Query! Other design features Query! Phase Not Applicable Query! Type of endpoint/s Efficacy Query! Statistical methods / analysis 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. Query!
Recruitment Recruitment status Not yet recruiting Query! Date of first participant enrolment Anticipated 27/04/2026 Query! Actual Query! Date of last participant enrolment Anticipated 29/06/2026 Query! Actual Query! Date of last data collection Anticipated 29/07/2026 Query! Actual Query! Sample size Target 18 Query! Accrual to date Query! Final Query! Recruitment in Australia Recruitment state(s) QLD Query!
Funding & Sponsors Funding source category [1] 321378 0 Government body Query! Name [1] 321378 0 Australian Department of Health, Disability and Ageing, Medical Research Futures Fund (MRFF) Query! Country [1] 321378 0 Australia Query! Primary sponsor type University Query! Name Queensland University of Technology Query! Address Query! Country Australia Query! Secondary sponsor category [1] 324351 0 None Query! Name [1] 324351 0 Query! Address [1] 324351 0 Query! Country [1] 324351 0 Query!
Ethics approval Ethics application status Approved Query! Ethics committee name [1] 319918 0 Queensland University of Technology University Human Research Ethics Committee Query! Ethics committee address [1] 319918 0 https://www.qut.edu.au/research/why-qut/ethics-and-integrity Query! Ethics committee country [1] 319918 0 Australia Query! Date submitted for ethics approval [1] 319918 0 01/12/2025 Query! Approval date [1] 319918 0 26/03/2026 Query! Ethics approval number [1] 319918 0 LR 2026-9938-28794 Query!
Summary Brief summary Diabetes-related foot ulceration is a debilitating condition that arises in part due to high mechanical pressures acting on the underside of the foot. Preventative offloading treatments including medical grade footwear and personalised insoles are often used to reduce these pressures in an effort to prevent ulceration in people who are determined to be high risk.
The research team have developed an approach to 3D print accessible and low-cost personalised metamaterial insoles with functionally graded stiffness that varies across the device. These insoles could potentially be used to enhance the effectiveness of pressure redistribution and prevention of diabetes related foot ulceration. This within-subjects repeated-measures crossover study in people at risk of diabetes related foot ulceration will compare the immediate effects on plantar pressures in medical grade footwear with personalised 3D printed metamaterial offloading insoles produced using automated design algorithms compared to medical grade footwear with the current standard of care personalised foam insoles. The results of this study will provide insight to the most suitable design algorithms for functionally graded insoles as part of preventative treatment. The findings of this study in people at risk of diabetes related foot ulceration will inform larger future studies evaluating the longer-term effects of the insoles in people at risk of diabetes-related foot ulceration. Query! Trial website Query! Trial related presentations / publications Query! Public notes Query!
Contacts Principal investigator Name 148818 0 Prof Mia Woodruff Query! Address 148818 0 Biofabrication and Tissue Morphology Group, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, QLD, 4059 Query! Country 148818 0 Australia Query! Phone 148818 0 +61 7 31387778 Query! Fax 148818 0 Query! Email 148818 0 [email protected] Query! Contact person for public queries Name 148819 0 Hamish Harvey Query! Address 148819 0 Biofabrication and Tissue Morphology Group, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, QLD, 4059 Query! Country 148819 0 Australia Query! Phone 148819 0 +61 7 3138 0296 Query! Fax 148819 0 Query! Email 148819 0 [email protected] Query! Contact person for scientific queries Name 148820 0 Hamish Harvey Query! Address 148820 0 Biofabrication and Tissue Morphology Group, Queensland University of Technology, 60 Musk Ave, Kelvin Grove, QLD, 4059 Query! Country 148820 0 Australia Query! Phone 148820 0 +61 7 3138 0296 Query! Fax 148820 0 Query! Email 148820 0 [email protected] Query!
Data sharing statement Will the study consider sharing individual participant data? Yes
Will there be any conditions when requesting access to individual participant data? Persons/groups eligible to request access:
• Data will be made available on QUT's publicly accessible data repository

Conditions for requesting access:
• -

What individual participant data might be shared? • De-identified individual participant data:
• Published results
What types of analyses could be done with individual participant data? • Any type of analysis (i.e. no restrictions on data re-use)
When can requests for individual participant data be made (start and end dates)? From:
After publication of main results
To:
No end date
Where can requests to access individual participant data be made, or data be obtained directly? • Data repository: Data will be made available on QUT's publicly accessible data repository, via https://data.researchdatafinder.qut.edu.au

Are there extra considerations when requesting access to individual participant data? No

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.