{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,16]],"date-time":"2025-10-16T20:45:10Z","timestamp":1760647510127,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2021,10,6]],"date-time":"2021-10-06T00:00:00Z","timestamp":1633478400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Numerous methods and devices are available for implant fixation in anterior cruciate ligament (ACL) reconstruction. Biomechanical data indicate high variability in fixation stability across different devices. This study aims to provide a better insight into measuring the structural characteristics and mechanical behavior of ACL implant fixations. Fourteen human tibial specimens with reconstructed ACLs were subjected to progressively increasing dynamic loading until failure. The motions of the tibia, the proximal and distal graft ends, as well as the testing frame and actuator, were continuously recorded via a motion tracking system. Significantly higher displacements of the machine actuator (1.0 mm at graft slippage onset, and 12.2 mm at ultimate load) were measured compared to the displacements of the proximal (0.8 and 4.3 mm, respectively) and distal graft (0.1 and 3.4 mm, respectively) ends. The displacements measured at different sites showed significant correlations. The provided data suggest significant and systematic inaccuracies in the stiffness and slippage of the fixation when using machine displacement, as commonly reported in the literature. The assessment of the distal graft displacement excludes the artifactual graft elongation, and most accurately reflects the graft slippage onset indicating clinical failure. Considering the high displacement at the ultimate load, the ultimate load could be used as a standardized variable to compare different fixation methods. However, the ultimate load alone is not sufficient to qualitatively describe fixation stability.<\/jats:p>","DOI":"10.3390\/s21196632","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T21:37:49Z","timestamp":1633901869000},"page":"6632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["On Measuring Implant Fixation Stability in ACL Reconstruction"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9029-7172","authenticated-orcid":false,"given":"Emir","family":"Benca","sequence":"first","affiliation":[{"name":"Department of Orthopedics and Trauma Surgery, Medical University of Vienna, 1090 Vienna, Austria"},{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0484-887X","authenticated-orcid":false,"given":"Ivan","family":"Zderic","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"}]},{"given":"Jan","family":"Caspar","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"}]},{"given":"Kenneth van","family":"Knegsel","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"},{"name":"Department of Orthopedics and Trauma Surgery, Cantonal Hospital of Lucerne, 6000 Lucerne, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5194-9118","authenticated-orcid":false,"given":"Lena","family":"Hirtler","sequence":"additional","affiliation":[{"name":"Center for Anatomy and Cell Biology, Division of Anatomy, Medical University of Vienna, 1090 Vienna, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9795-115X","authenticated-orcid":false,"given":"Boyko","family":"Gueorguiev","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9739-6176","authenticated-orcid":false,"given":"Harald","family":"Widhalm","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Trauma Surgery, Medical University of Vienna, 1090 Vienna, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6321-1804","authenticated-orcid":false,"given":"Reinhard","family":"Windhager","sequence":"additional","affiliation":[{"name":"Department of Orthopedics and Trauma Surgery, Medical University of Vienna, 1090 Vienna, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2738-6436","authenticated-orcid":false,"given":"Peter","family":"Varga","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"462","DOI":"10.1016\/j.knee.2013.10.009","article-title":"Is reconstruction the best management strategy for anterior cruciate ligament rupture? 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