{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T20:01:50Z","timestamp":1772222510676,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,10]],"date-time":"2021-08-10T00:00:00Z","timestamp":1628553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["EP\/R01513\/1"],"award-info":[{"award-number":["EP\/R01513\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002383","name":"King Saud University","doi-asserted-by":"publisher","award":["RSP-2021\/299"],"award-info":[{"award-number":["RSP-2021\/299"]}],"id":[{"id":"10.13039\/501100002383","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The use of external fixation devices is considered a valuable approach for the treatment of bone fractures, providing proper alignment to fractured fragments and maintaining fracture stability during the healing process. The need for external fixation devices has increased due to an aging population and increased trauma incidents. The design and fabrication of external fixations are major challenges since the shape and size of the defect vary, as well as the geometry of the human limb. This requires fully personalized external fixators to improve its fit and functionality. This paper presents a methodology to design personalized lightweight external fixator devices for additive manufacturing. This methodology comprises data acquisition, Computer tomography (CT) imaging analysis and processing, Computer Aided Design (CAD) modelling and two methods (imposed predefined patterns and topology optimization) to reduce the weight of the device. Finite element analysis with full factorial design of experiments were used to determine the optimal combination of designs (topology optimization and predefined patterns), materials (polylactic acid, acrylonitrile butadiene styrene, and polyamide) and thickness (3, 4, 5 and 6 mm) to maximize the strength and stiffness of the fixator, while minimizing its weight. The optimal parameters were found to correspond to an external fixator device optimized by topology optimization, made in polylactic acid with 4 mm thickness.<\/jats:p>","DOI":"10.3390\/polym13162661","type":"journal-article","created":{"date-parts":[[2021,8,10]],"date-time":"2021-08-10T08:57:14Z","timestamp":1628585834000},"page":"2661","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Optimization of a Patient-Specific External Fixation Device for Lower Limb Injuries"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9178-8168","authenticated-orcid":false,"given":"Mohammed S.","family":"Alqahtani","sequence":"first","affiliation":[{"name":"Mechanical Engineering Department, College of Engineering, King Saud University, Riyadh 11451, Saudi Arabia"},{"name":"School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester M13 9PL, UK"}]},{"given":"Abdulsalam Abdulaziz","family":"Al-Tamimi","sequence":"additional","affiliation":[{"name":"Industrial Engineering Department, College of Engineering, King Saud University, Riyadh 11451, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0832-8559","authenticated-orcid":false,"given":"Mohamed H.","family":"Hassan","sequence":"additional","affiliation":[{"name":"School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester M13 9PL, UK"}]},{"given":"Fengyuan","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, School of Civil, Aerospace and Mechanical Engineering, Faculty of Engineering, University of Bristol, Bristol BS8 1TR, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3683-726X","authenticated-orcid":false,"given":"Paulo","family":"Bartolo","sequence":"additional","affiliation":[{"name":"School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester M13 9PL, UK"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Dichio, G., Cal\u00ec, M., Terzini, M., Putame, G., Zanetti, E.M., Costa, P., and Audenino, A.L. 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