Orthofeet: A Prospective Proof of Concept Trial to Evaluate an Innovative Pain Relief Footwear

Changes in foot pain from baseline to 6 weeks for each intervention (Orthofeet and own shoes) will be assessed using the Foot Function Index (FFI) questionnaire. The FFI consists of four overall scores, including three subscales: 1) Pain Score (the primary outcome in this study), 2) Disability Score, 3) Activity Limitation Score, and 4) Overall Score.

The Pain subscale asks participants to rate their foot pain on a scale of 0 (no pain) to 10 (worst imaginable pain), based on their experiences during various activities over the past two weeks. For this outcome, we focused on the FFI pain subscore related to the worst foot pain experienced over the last two weeks.

To report the final results, participants from intervention A (Orthofeet) and intervention B (own shoes) were combined from groups AB and BA.

Step count will be measured over the course of 6 weeks for each intervention arm (Intervention A (Orthofeet) and Intervention B (own shoes)) using a smartwatch (Vivosmart 4, Garmin, USA). Steps per day were recorded in 15-min intervals and summed over each 24-h period. For analysis, the mean daily steps from the last seven consecutive days of each footwear condition (A and B) were calculated for each participant.

Active kilocalories (calories burned through physical activity, excluding basal metabolic rate) measured by the smartwatch (Vivosmart watch, Garmin) over the last seven consecutive days were extracted for each intervention period: A (Orthofeet) and B (own shoes). The 90th percentile of daily active kilocalories recorded by the smartwatch from baseline to 6 weeks was included in the analysis.

Foot pain at baseline and 6 weeks for each intervention (Orthofeet and own shoes) will be assessed using the Foot Function Index (FFI) questionnaire. The pain subscale asks participants to rate their foot pain on a scale from 0 (no pain) to 10 (worst imaginable pain) based on their experiences during various activities over the past two weeks. Seven of the nine questions were summed for final analysis, excluding "pain walking with orthotics" and "pain standing with orthotics," as the focus was to compare Orthofeet shoes to participants' own shoes, not prescribed orthoses. The resulting total score ranges from 0 to 70, with higher values indicating worse overall pain.

The disability level at baseline and week 6 was assessed using the disability subscale of the Foot Function Index (FFI). This subscale consists of nine items that evaluate the difficulty experienced in performing various functional activities due to foot problems. These activities include walking inside and outside the house, climbing and descending stairs, getting out of a chair, standing on tiptoe, climbing curbs, and running or fast walking.

Each item is rated on a scale from 0 (no difficulty) to 10 (so difficult it requires help). The scores for the disability subscale range from 0 to 90, with higher scores indicating greater disability.

Physical activity limitations at baseline and were assessed using the Activity Limitation subscale of the Foot Function Index (FFI). This subscale comprises five items that evaluate the extent to which foot problems restrict a person's physical activities, including walking distances, standing on tiptoe, climbing stairs, and engaging in vigorous activities.

Each item is rated on a scale from 0 (no limitation) to 10 (maximum limitation), with higher scores indicating greater activity limitation. The total score for this subscale ranges from 0 to 50.

In this study, changes from baseline at week 6 for each intervention duration were assessed and reported.

In this study the changes from baseline at week 6 for each intervention duration was assessed and reported

We used a Garmin smartwatch to report the Daily Metabolic Equivalent of Task (METs). Median daily MET values over the last seven consecutive days for each participant, during each footwear condition (Orthofeet shoes and their own shoes), were calculated following the guidelines of the American College of Sports Medicine (ACSM) and the American Heart Association (AHA) (Haskell et al., 2007).

To calculate MET-minutes per week (MET·min·wk-¹), the median daily METs were multiplied by 60, as recommended by ACSM and AHA. The mean values for the calculated "Median daily MET" across all participants, during periods when they wore Orthofeet shoes and their own shoes, were computed and reported.