{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T08:32:18Z","timestamp":1786696338905,"version":"build-2736575974"},"reference-count":27,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000104","name":"NASA\/MSFC","doi-asserted-by":"publisher","award":["80NSSC22M0208"],"award-info":[{"award-number":["80NSSC22M0208"]}],"id":[{"id":"10.13039\/100000104","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Peripheral neuropathy degrades gait mechanics, elevating peak plantar pressures (PPP) and tissue ulceration risks. This exploratory pilot study evaluates custom orthotics using thermo-mechanically synthesized re-entrant auxetic foam insoles with targeted dome-shaped inserts. Bilateral dynamic gait analysis was conducted across a heterogeneous cohort (N = 9) utilizing a P-Walk 600 pressure plate and a MARVUE 2D motion capture system inside standardized footwear. To address small-sample limits, a non-parametric bootstrap resampling analysis (B = 1000) was executed. Native auxetic foam demonstrated high internal consistency ((\u03c3*) = 12.063 kPa, Consistency Rank = 1), showing a strong numerical propensity to restrict load distribution variability compared to factory-installed over-the-counter (OTC) memory foam controls. While initial cell-adaptation cycles were observed, custom insoles reduced PPP by up to 62.2% in systemic polyneuropathies, shifting signatures beneath the exploratory clinical safety target (&lt;200 kPa) in 55% of simulated cases. Conversely, customization triggered an adverse volumetric crowding effect in focal mononeuropathies, suggesting un-customized native auxetic foam as the preferred structural configuration for this specific cohort to avoid premature cell densification. Re-entrant cellular structures accommodate heterogeneous pathomechanics, offering an exploratory pathway for patient-specific orthotic optimization.<\/jats:p>","DOI":"10.3390\/ma19163446","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T08:08:29Z","timestamp":1786694909000},"page":"3446","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Technical Feasibility of Custom-Fabricated Auxetic Foam Insoles for Plantar Pressure Redistribution: An Exploratory Pilot and Bootstrap Resampling Investigation"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3338-4197","authenticated-orcid":false,"given":"LaBreesha","family":"Batey","sequence":"first","affiliation":[{"name":"Department of Mechanical and Materials Engineering, The University of Alabama at Birmingham, 1075 13th St S, Birmingham, AL 35294, USA"},{"name":"Human Landing System Branch, George C. Marshall Space Flight Center, National Aeronautics and Space Administration, 4631 Saturn RD, Huntsville, AL 35812, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Enrique M.","family":"Jackson","sequence":"additional","affiliation":[{"name":"Material Science Branch, George C. Marshall Space Flight Center, National Aeronautics and Space Administration, 4631 Saturn RD, Huntsville, AL 35812, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0855-3497","authenticated-orcid":false,"given":"Changchun","family":"Zeng","sequence":"additional","affiliation":[{"name":"Department of Industrial and Manufacturing Engineering, FAMU-FSU College of Engineering, Florida Agricultural and Mechanical University, 2525 Pottsdamer St., Tallahassee, FL 32310, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Selvum","family":"Pillay","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Materials Engineering, The University of Alabama at Birmingham, 1075 13th St S, Birmingham, AL 35294, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"ref_1","unstructured":"Mayo Clinic (2025, July 07). 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