{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:55:14Z","timestamp":1785412514524,"version":"3.56.0"},"reference-count":40,"publisher":"ASME International","issue":"3","license":[{"start":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T00:00:00Z","timestamp":1767830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.asme.org\/publications-submissions\/publishing-information\/legal-policies"}],"funder":[{"DOI":"10.13039\/100000069","name":"National Institute of Arthritis and Musculoskeletal and Skin Diseases","doi-asserted-by":"publisher","award":["R01AR071985"],"award-info":[{"award-number":["R01AR071985"]}],"id":[{"id":"10.13039\/100000069","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["asmedigitalcollection.asme.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,3,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Anterior cruciate ligament (ACL) reconstruction in pediatric patients has a higher graft failure rate compared to adults. Restoring joint stability and reducing graft failure is essential. However, how graft biomechanical properties change with age and affect reconstruction outcomes remains unclear. This study investigated the biomechanical development of porcine flexor tendons across skeletal growth and evaluated how graft size and stiffness influence knee biomechanics in a pediatric porcine model. Flexor tendons (n\u2009=\u200957) were harvested from pigs at 0.5, 1.5, 5, and 9\u2009months of age to measure cross-sectional area (CSA), stiffness, and failure load. ACLs in nine early adolescent porcine knees were reconstructed using both 1.5- and 5-month-old (1.5\u2009mo and 5\u2009mo) grafts and tested under anterior\u2013posterior, compressive, and varus\u2013valgus (VV) loading at 40\u2009deg of flexion using a robotic testing system. ACL and graft forces were calculated, and in situ properties were derived from force\u2013displacement curves. Tendon CSA, stiffness, and failure load increased with age, and stiffness associated with CSA. The CSA of 5\u2009mo tendons was 57% greater than that of 1.5\u2009mo tendons, but stiffness increased only 20%. ACL reconstruction with 5\u2009mo grafts resulted in 29% less anterior\u2013posterior tibial translation and 44% higher graft force compared to 1.5\u2009mo grafts. In situ stiffness of 5\u2009mo grafts was 51% higher than 1.5\u2009mo grafts. These findings highlight the differences between tendon size and biomechanical development, which together contribute to the improvements in joint function following ACL reconstruction.<\/jats:p>","DOI":"10.1115\/1.4070647","type":"journal-article","created":{"date-parts":[[2025,12,12]],"date-time":"2025-12-12T16:22:43Z","timestamp":1765556563000},"update-policy":"https:\/\/doi.org\/10.1115\/crossmarkpolicy-asme","source":"Crossref","is-referenced-by-count":0,"title":["Age-Related Increases in Graft Tendon Size and Stiffness During Skeletal Growth Enhance Anterior Cruciate Ligament Graft Function and Joint Stability in an Early Adolescent Porcine Model"],"prefix":"10.1115","volume":"148","author":[{"given":"Yukun","family":"Zhang","sequence":"first","affiliation":[{"name":"Lampe Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill , Raleigh, NC 27695; , Raleigh, NC 27695"},{"name":"Comparative Medicine Institute, North Carolina State University , Raleigh, NC 27695; , Raleigh, NC 27695"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaan","family":"Gurbuz","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Traumatology, Kayseri Medical Faculty, University of Health Sciences , Kayseri 38039, T\u00fcrkiye; , Raleigh, NC 27695"},{"name":"Lampe Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill , Kayseri 38039, T\u00fcrkiye; , Raleigh, NC 27695"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua","family":"Chavez-Arellano","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, North Carolina State University , Raleigh, NC 27695"},{"id":[{"id":"https:\/\/ror.org\/04tj63d06","id-type":"ROR","asserted-by":"publisher"}],"name":"North Carolina State University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Logan","family":"Opperman","sequence":"additional","affiliation":[{"name":"Department of Statistics, North Carolina State University , Raleigh, NC 27695"},{"id":[{"id":"https:\/\/ror.org\/04tj63d06","id-type":"ROR","asserted-by":"publisher"}],"name":"North Carolina State University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeffrey T.","family":"Spang","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of North Carolina at Chapel Hill , Chapel Hill, NC 27599"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew B.","family":"Fisher","sequence":"additional","affiliation":[{"name":"Lampe Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill , Raleigh, NC 27695; , 4130 Engineering Building III, CB7115, Raleigh, NC 27695; , Chapel Hill, NC 27599"},{"name":"Comparative Medicine Institute, North Carolina State University , Raleigh, NC 27695; , 4130 Engineering Building III, CB7115, Raleigh, NC 27695; , Chapel Hill, NC 27599"},{"name":"Department of Orthopaedics, University of North Carolina at Chapel Hill , Raleigh, NC 27695; , 4130 Engineering Building III, CB7115, Raleigh, NC 27695; , Chapel Hill, NC 27599"},{"id":[{"id":"https:\/\/ror.org\/04tj63d06","id-type":"ROR","asserted-by":"publisher"}],"name":"North Carolina State University"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"33","published-online":{"date-parts":[[2026,1,8]]},"reference":[{"issue":"4","key":"2026011309142459100_bib1","doi-asserted-by":"crossref","first-page":"e20.00106","DOI":"10.2106\/JBJS.OA.20.00106","article-title":"Failure Rates of Autograft and Allograft ACL Reconstruction in Patients 19 Years of Age and Younger","volume":"5","year":"2020","journal-title":"JBJS Open Access"},{"issue":"5","key":"2026011309142459100_bib2","doi-asserted-by":"crossref","first-page":"447","DOI":"10.1097\/BPO.0000000000000482","article-title":"Trends in Pediatric and Adolescent Anterior Cruciate Ligament Injury and Reconstruction","volume":"36","year":"2016","journal-title":"J. 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