{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T17:09:45Z","timestamp":1785431385718,"version":"3.56.0"},"reference-count":30,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T00:00:00Z","timestamp":1782432000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["JP25K14691"],"award-info":[{"award-number":["JP25K14691"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["JP21K18054"],"award-info":[{"award-number":["JP21K18054"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"award":["JP25K14691"],"award-info":[{"award-number":["JP25K14691"]}],"id":[{"id":"https:\/\/ror.org\/00hhkn466","id-type":"ROR","asserted-by":"publisher"}]},{"award":["JP21K18054"],"award-info":[{"award-number":["JP21K18054"]}],"id":[{"id":"https:\/\/ror.org\/00hhkn466","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Bone\u2013patellar tendon\u2013bone (BPTB) grafts used in anterior cruciate ligament reconstruction bend at the femoral tunnel aperture, forming a graft bending angle (GBA). However, the mechanical effects of GBA-related angled loading on bone\u2013BPTB graft constructs remain unclear. This study investigated the effects of GBA and cyclic tensile loading on stiffness and elongation using porcine BPTB grafts. Fourteen specimens were assigned to tibial bone plug constructs (Type T, n = 7) or patellar bone plug constructs (Type P, n = 7). Each construct was cyclically loaded between 10 and 50 N for 50 cycles under GBA conditions of 0\u00b0, 30\u00b0, 60\u00b0, and 90\u00b0. Regardless of GBA condition, cyclic loading produced substantial increases in stiffness and elongation during the first 10 cycles, followed by smaller changes. Stiffness tended to decrease under greater GBA conditions, particularly in Type T constructs, where 60\u00b0 and 90\u00b0 reduced stiffness and increased elongation. Type P stiffness showed little dependence on GBA. At 0\u00b0 and 30\u00b0, Type P showed lower stiffness and greater elongation than Type T. These findings indicate that bone\u2013BPTB graft tensile behavior is governed by GBA-related loading geometry and bone plug\u2013tendon junction morphology.<\/jats:p>","DOI":"10.3390\/bioengineering13070752","type":"journal-article","created":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T05:58:04Z","timestamp":1782799084000},"page":"752","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of Graft Bending Angle on the Tensile Behavior of Bone Tunnel-Graft Constructs for Anterior Cruciate Ligament Reconstruction Using Bone-Patellar Tendon\u2013Bone Graft"],"prefix":"10.3390","volume":"13","author":[{"given":"Satoshi","family":"Yamakawa","sequence":"first","affiliation":[{"name":"Department of Health and Sport Sciences, Medicine for Sports and Performing Arts, Graduate School of Medicine, The University of Osaka, Osaka 565-0871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Konsei","family":"Shino","sequence":"additional","affiliation":[{"name":"Sports Orthopaedic Center, Yukioka Hospital, 2-2-3 Ukita, Osaka 530-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6691-8290","authenticated-orcid":false,"given":"Tomoki","family":"Ohori","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Graduate School of Medicine, The University of Osaka, Osaka 565-0871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ken","family":"Nakata","sequence":"additional","affiliation":[{"name":"Department of Health and Sport Sciences, Medicine for Sports and Performing Arts, Graduate School of Medicine, The University of Osaka, Osaka 565-0871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1178","DOI":"10.1016\/j.arthro.2008.06.010","article-title":"Rectangular tunnel double-bundle anterior cruciate ligament reconstruction with bone\u2013patellar tendon\u2013bone graft to mimic natural fiber arrangement","volume":"24","author":"Shino","year":"2008","journal-title":"Arthroscopy"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"23259671211013327","DOI":"10.1177\/23259671211013327","article-title":"Clinical outcome evaluation of anatomic anterior cruciate ligament reconstruction with tunnel positioning using gold standard techniques: A systematic review and meta-analysis","volume":"9","author":"Fernandes","year":"2021","journal-title":"Orthop. 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