{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:35:00Z","timestamp":1760060100102,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,8,1]],"date-time":"2025-08-01T00:00:00Z","timestamp":1754006400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomechanics"],"abstract":"<jats:p>Background\/Objectives: The simulation of human movement offers transformative potential for the design of medical devices, particularly in understanding the cause\u2013effect dynamics in individuals with neurological or musculoskeletal impairments. This study presents a simulation-driven framework to determine the optimal ankle\u2013foot orthosis (AFO) stiffness for mitigating the risk of ankle sprains due to excessive subtalar inversion during high-impact activities, such as landing from a free fall. Methods: We employed biomechanical simulations to assess the influence of translational stiffness on subtalar inversion control, given that inversion angles exceeding 25 degrees are strongly correlated with injury risk. Simulations were conducted using a musculoskeletal model with and without a passive AFO; the stiffness varied in three anatomical directions. A Design of Experiments (DoE) approach was utilized to capture nonlinear interactions among stiffness parameters. Results: The results indicated that increased translational stiffness significantly reduced inversion angles to safer levels, though direction\u2013dependent effects were noted. Based on these insights, we developed a 4D visualization tool that integrates simulation data with an interactive color\u2013coded interface to depict \u201dsafe design\u201d zones for various AFO stiffness configurations. This tool supports clinicians in selecting stiffness values that optimize both safety and functional performance. Conclusions: The proposed framework enhances clinical decision-making and engineering processes by enabling more accurate and individualized AFO designs.<\/jats:p>","DOI":"10.3390\/biomechanics5030055","type":"journal-article","created":{"date-parts":[[2025,8,5]],"date-time":"2025-08-05T08:46:55Z","timestamp":1754383615000},"page":"55","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Simulation\u2013Driven Design of Ankle\u2013Foot Orthoses Using DoE Optimization and 4D Visualization"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2799-305X","authenticated-orcid":false,"given":"Marta","family":"Carvalho","sequence":"first","affiliation":[{"name":"UNIDEMI, Department of Mechanical and Industrial Engineering, NOVA School of Science and Technology, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"},{"name":"Laborat\u00f3rio Associado de Sistemas Inteligentes, LASI, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3302-0935","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Milho","sequence":"additional","affiliation":[{"name":"IDMEC, Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, 1049-001 Lisboa, Portugal"},{"name":"CIMOSM, Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, 1959-007 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1016\/j.piutam.2011.04.021","article-title":"OpenSim: A musculoskeletal modeling and simulation framework for in silico investigations and exchange","volume":"2","author":"Seth","year":"2011","journal-title":"Procedia IUTAM"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1115\/1.2891163","article-title":"The Effect of Damage to the Lateral Collateral Ligaments on the Mechanical Characteristics of the Ankle Joint\u2014An In-Vitro Study","volume":"112","author":"Siegler","year":"1990","journal-title":"J. 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