{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T04:56:12Z","timestamp":1790571372784,"version":"4.1.0"},"reference-count":21,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T00:00:00Z","timestamp":1790553600000},"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. Med."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Knee pain may induce protective gait patterns that reduce knee loading, but the multi-joint trade-offs that emerge under uneven-terrain demands remain uncertain.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Using SCONE\/Hyfydy, we generated sagittal-plane predictive simulations over a deterministic ten-tile terrain sequence. A reflex-based controller was optimized under no knee-load limit (C0) or bilateral soft limits of 4, 3, or 2 body weights (C4, C3, and C2). We retained the lowest-objective solution from 24 runs per condition and reanalyzed every complete stance within 1\u201312 s by limb and terrain.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The C0 knee joint-reaction-force peaks of 8.35\/8.25 BW (left\/right) occurred during early stance on tile 9 (\u22124\u00b0) and tile 10 (\u22122\u00b0), respectively. The left peak arose in a stance confined to tile 9, whereas the right peak arose in a stance that crossed the tile 9-to-10 boundary; neither occurred during initialization. Corresponding maxima were 4.51\/4.34 BW in C4, 3.63\/3.71 BW in C3, and 3.60\/3.73 BW in C2. Mean stance impulse decreased from 2.14\/2.00 BW\u00b7s in C0 to 1.79\/1.82, 1.65\/1.69, and 1.58\/1.59 BW\u00b7s in C4, C3, and C2, respectively. Evaluation-window mean hip loading increased and speed decreased, whereas initial loading rate did not change monotonically. The selected solution ranked first by objective in every condition; 5\u201317 of 24 runs were within 10% of the selected objective.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Within this model, controller, weighting scheme, and single terrain traversal, knee-load limiting was associated with slower walking, lower stance-phase knee peaks and impulses, and hip-dominant redistribution. These results are scenario-specific model behaviors rather than direct clinical predictions.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmed.2026.1912600","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T04:28:53Z","timestamp":1790569733000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Bilateral knee-load limiting during uneven-terrain walking induces hip-dominant load redistribution in predictive gait simulations"],"prefix":"10.3389","volume":"13","author":[{"given":"Heun-Jae","family":"Ryu","sequence":"first","affiliation":[{"name":"Department of Physical Therapy, Honam University, Gwangju, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dong-Kyun","family":"Koo","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, Wonkwang University, Iksan-si, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,28]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"819","DOI":"10.1136\/annrheumdis-2019-216515","article-title":"Global, regional and national burden of osteoarthritis 1990\u20132017: a systematic analysis of the Global Burden of Disease Study 2017","volume":"79","author":"Safiri","year":"2020","journal-title":"Ann Rheum Dis"},{"key":"B2","doi-asserted-by":"publisher","first-page":"745","DOI":"10.1002\/pmrj.12066","article-title":"Risk factors for falls in adults with knee osteoarthritis: a systematic review","volume":"11","author":"Manlapaz","year":"2019","journal-title":"PM R"},{"key":"B3","doi-asserted-by":"publisher","first-page":"3963","DOI":"10.1242\/jeb.081711","article-title":"Biomechanics and energetics of walking on uneven terrain","volume":"216","author":"Voloshina","year":"2013","journal-title":"J Exp Biol"},{"key":"B4","doi-asserted-by":"publisher","first-page":"S90","DOI":"10.1016\/j.pain.2010.10.020","article-title":"Moving differently in pain: a new theory to explain the adaptation to pain","volume":"152","author":"Hodges","year":"2011","journal-title":"Pain"},{"key":"B5","doi-asserted-by":"publisher","first-page":"245","DOI":"10.1146\/annurev.bioeng.3.1.245","article-title":"Computer modeling and simulation of human movement","volume":"3","author":"Pandy","year":"2001","journal-title":"Annu Rev Biomed Eng"},{"key":"B6","doi-asserted-by":"publisher","first-page":"1346365","DOI":"10.3389\/fbioe.2024.1346365","article-title":"Is increased trunk flexion in standing up related to muscle weakness or pain avoidance in individuals with unilateral knee pain; 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