Long-term Effects of Using a Novel Orthotic Insole for Tactile Stimulation in Diabetic Peripheral Neuropathy and Follow-up

Summary

1. This study had the objectives to investigate the long-term and remaining effects of using a novel vibrating foot orthosis for tactile stimulation in diabetic peripheral neuropathy (DPN).
2. The hypothesis of this study was using the VFO in conjunction with a random square wave pulse stimulus and pseudorandom white noise via a stochastic resonance could effectively improve tactile sensitivity and reduce vibration perception threshold (VPT).
3. Participants were recruited from the HRH Princess Maha Chakri Sirindhorn Medical Centre (Srinakharinwirot University), Ongkharak, Nakhon Nayok, Thailand.
4. 64 type 2 diabetes mellitus people with mild-to-moderate peripheral neuropathy were recruited.
5. Approach to participant: use purposive sampling by direct contact the patients who match the inclusion criteria.
6. Informed Consent Process: the information sheet was provided to participants, and the researcher explained the objectives of the study, the duration of the research, the research method, the dangers or potential effects of the research, including the benefits that might arise from the research and other methods of treatment in details. The participants had enough time and opportunity to ask questions until they had a good understanding. The researchers willingly answered questions without hiding them, until they satisfied. Then, the participants had to willingly sign a consent form prior to participate in the research project with voluntary.
7. The study protocol was approved by the Human Research Ethics Committee of Srinakharinwirot University (SWUEC-661032).
8. A randomized sham-controlled trial was conducted in this study. The experiments in this study were performed in a parallel design with random allocation and a double-blind strategy (blinded participants and investigators).
9. Baseline characteristics were assessed including: muscle strength by manual muscle testing, grading by the Medical Research Council; sensation by the Semmes-Weinstein monofilament test (5.07 gauge, 10 g pressure size) with 10-site examination; peripheral neuropathy by the Michigan neuropathy screening instrument; vibratory perception by a tuning fork (a graduated Rydel-Seiffer version); body mass index; circulatory system examination by palpating dorsalis pedis and posterior tibial pulse; pathology of diabetic foot; VPT by the Vibratory Sensory Analyzer: VSA-3000 (Medoc Ltd., USA).
10. VPT values were determined as the outcome parameter.
11. Statistical methods:

* Quantitative data will be presented with median (mean) and standard deviation (SD).
* Qualitative data will be presented with numbers and percentages.
* An independent t-test will be used to compare the independent outcomes.
* A paired t-test will be used to compare the dependent outcomes.
* A repeated-measures ANCOVA will be used for between group comparisons.
* A repeated-measures ANOVA will be used for within-group comparison.
* MANCOVA will be used for analyzing the covariates' effect on the relationship between the independent grouping variables and the continuous dependent variables.
* Cohen's d will be used to determine the effect sizes.
12. Ethical Consideration (1) All participants were provided with detailed project information prior to participation in the research project.

(2) While conducting experiments, evaluating, collecting research results, a prosthetist and orthotist (PO) and a physician will be with the participants at all times to prevent possible accidents/adverse events.

(3) If there is any harm from the research, free medical treatment will be provided.

(4) During research participation, all participants have the rights to withdraw at any time without the need to give reasons.

(5) All information obtained from the research project will be kept as a secret, and will be disclosed to the public for academic benefits without the participants' name.

13\. Expectable benefits and applications

1. Using the novel VFO may lead to efficient treatment for neurorehabilitation in DPN.
2. The investigators hope that this low-cost VFO can offer advantages such as affordability, widespread use, and home-based applications.
3. The benefits of using the novel VFO that can improve tactile sensation on the plantar surface of the foot in diabetic peripheral neuropathy.
4. Employing the novel VFO can reduce VPT.
5. Using the novel VFO can help prevent diabetic foot ulceration (DFU), lessen a risk of DFU recurrence, and avoid lower limb amputation.
6. Applying the novel VFO may help restore and prolong tactile sensation.
7. Using the novel VFO may aid in slowing DPN deterioration and decreasing peripheral nervous system impairment.
8. Utilizing the VFO may help improve quality of life for DPN people.

14\. Compensations for participants

* Payment was provided for those participants who attend throughout the study.
* All participants received a custom-made foot orthosis after completing the study.

Conditions

• Diabetic Peripheral Neuropathy Type 2

Interventions

DEVICE

Using vibrating foot orthosis with tactile stimulation

Stimulating tactile sensation by using vibrating foot orthosis in conjunction with a random 0-100 Hz square wave pulse stimulus and pseudorandom white noise via a stochastic resonance approach.

DEVICE

Using vibrating foot orthosis without tactile stimulation

Stimulating tactile sensation by using vibrating foot orthosis with only vibration 100 Hz freqency.

Sponsors & Collaborators

• Srinakharinwirot University

  lead OTHER

Principal Investigators

• Natapatchakrid Thimabut, Ph.D. · Srinakharinwirot University

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-06-12

Primary Completion

2023-11-30

Completion

2023-12-29

Countries

• Thailand

Study Locations