{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T16:26:37Z","timestamp":1784996797181,"version":"3.55.0"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T00:00:00Z","timestamp":1719792000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Bioeng. Biotechnol."],"abstract":"<jats:p>People with unilateral transtibial amputation (TTA) using a passive-elastic prosthesis exhibit lower positive affected leg trailing work (AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos<\/jats:sub>) and a greater magnitude of negative unaffected leg leading work (UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg<\/jats:sub>) during walking than non-amputees, which may increase joint pain and osteoarthritis risk in the unaffected leg. People with TTA using a stance-phase powered prosthesis (e.g., BiOM, Ottobock, Duderstadt, Germany) walk with increased AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos<\/jats:sub> and potentially decreased magnitude of UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg<\/jats:sub> compared to a passive-elastic prosthesis. The BiOM includes a passive-elastic prosthesis with a manufacturer-recommended stiffness category and can be tuned to different power settings, which may change AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos,<\/jats:sub> UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg,<\/jats:sub> and the prosthesis effective foot length ratio (EFLR). Thirteen people with TTA walked using 16 different prosthetic stiffness category and power settings on a level treadmill at 0.75\u20131.75\u00a0m\/s. We constructed linear mixed effects models to determine the effects of stiffness category and power settings on AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos,<\/jats:sub> UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg,<\/jats:sub> and EFLR and hypothesized that decreased stiffness and increased power would increase AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos<\/jats:sub>, not change and decrease UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg<\/jats:sub> magnitude, and decrease and not change prosthesis EFLR, respectively. We found there was no significant effect of stiffness category on AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos<\/jats:sub> but increased stiffness reduced UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg<\/jats:sub> magnitude, perhaps due to a 0.02 increase in prosthesis EFLR compared to the least stiff category. Furthermore, we found that use of the BiOM with 10% and 20% greater than recommended power increased AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos<\/jats:sub> and decreased UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg<\/jats:sub> magnitude at 0.75\u20131.00\u00a0m\/s. However, prosthetic power setting depended on walking speed so that use of the BiOM increased UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg<\/jats:sub> magnitude at 1.50\u20131.75\u00a0m\/s compared to a passive-elastic prosthesis. Ultimately, our results suggest that at 0.75\u20131.00\u00a0m\/s, prosthetists should utilize the BiOM attached to a passive-elastic prosthesis with an increased stiffness category and power settings up to 20% greater than recommended based on biological ankle values. This prosthetic configuration can allow people with unilateral transtibial amputation to increase AL<jats:sub>trail<\/jats:sub> W<jats:sub>pos<\/jats:sub> and minimize UL<jats:sub>lead<\/jats:sub> W<jats:sub>neg<\/jats:sub> magnitude, which could reduce joint pain and osteoarthritis risk in the unaffected leg and potentially lower the metabolic cost of walking.<\/jats:p>","DOI":"10.3389\/fbioe.2024.1336520","type":"journal-article","created":{"date-parts":[[2024,7,1]],"date-time":"2024-07-01T05:03:05Z","timestamp":1719810185000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":7,"title":["Greater than recommended stiffness and power setting of a stance-phase powered leg prosthesis can improve step-to-step transition work and effective foot length ratio during walking in people with transtibial amputation"],"prefix":"10.3389","volume":"12","author":[{"given":"Joshua R.","family":"Tacca","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zane A.","family":"Colvin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alena M.","family":"Grabowski","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2024,7,1]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"3953","DOI":"10.1242\/jeb.02455","article-title":"The advantages of a rolling foot in human walking","volume":"209","author":"Adamczyk","year":"2006","journal-title":"J. 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