{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T11:03:35Z","timestamp":1789556615384,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:00:00Z","timestamp":1789516800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Background: Ipsilateral graft retear after anterior cruciate ligament reconstruction (ACLR) remains a major concern in athletes, while the relationship between postoperative mechanical and functional measures and retear remains uncertain. Methods: This cohort study included 48 athletes after primary unilateral ACLR with hamstring-tendon autograft. Follow-up was scheduled at 6, 9, and 12 months (184 \u00b1 13, 276 \u00b1 17, and 368 \u00b1 22 days), and the analytic export retained one postoperative value per athlete for GNRB side-to-side laxity at 250 N, concentric isokinetic quadriceps limb symmetry index (LSI) at 60\u00b0\/s, single-leg hop-for-distance LSI, and patient-reported outcomes, without preserving the originating visit. MRI-confirmed ipsilateral graft retear was recorded within 24 months after clinically suspected reinjury; retear dates were not retained. Results: Fourteen athletes (29.2%) sustained a retear. Quadriceps LSI was lower in the retear group than in the no-retear group (81.3 \u00b1 7.5% vs. 88.1 \u00b1 9.0%; p = 0.011), and each 1-SD higher quadriceps LSI was associated with lower retear odds (OR 0.43, 95% CI 0.21\u20130.89). In an exploratory threshold analysis, quadriceps LSI &lt; 85% was associated with a higher retear proportion (RR 3.21, 95% CI 1.17\u20138.82). Associations for knee laxity, hop performance, and patient-reported outcomes were not statistically robust. Conclusions: Postoperative quadriceps symmetry showed the clearest association with 24-month graft-retear status. However, because the originating measurement visit and retear dates were unavailable, temporal precedence could not be established, and the exploratory &lt;85% LSI finding should not be interpreted as a validated return-to-sport threshold.<\/jats:p>","DOI":"10.3390\/life16091546","type":"journal-article","created":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T10:09:17Z","timestamp":1789553357000},"page":"1546","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Postoperative Quadriceps Symmetry, Knee Laxity, and Single-Leg Hop Performance in Association with 24-Month Ipsilateral Graft Retear After Anterior Cruciate Ligament Reconstruction: A Cohort Study"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9138-6994","authenticated-orcid":false,"given":"Georgios","family":"Kakavas","sequence":"first","affiliation":[{"name":"Fysiotek Spine & Sports Lab, 17562 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5220-8992","authenticated-orcid":false,"given":"Nikolaos","family":"Malliaropoulos","sequence":"additional","affiliation":[{"name":"Thessaloniki Sports Medicine Clinic, 54622 Thessaloniki, Greece"},{"name":"Sports Clinic, Rheumatology Department, Barts Health NHS Trust, London E1 1BB, UK"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8650-2746","authenticated-orcid":false,"given":"Florian","family":"Forelli","sequence":"additional","affiliation":[{"name":"Haute-Ecole Arc Sant\u00e9, HES-SO University of Applied Sciences and Arts Western Switzerland, 2800 Del\u00e9mont, Switzerland"},{"name":"Orthopaedic Surgery Department, Clinic of Domont, Ramsay Healthcare, OrthoLab, 95330 Domont, France"},{"name":"Soci\u00e9t\u00e9 Fran\u00e7aise des Masseurs-Kin\u00e9sith\u00e9rapeutes du Sport Lab, 93380 Pierrefitte-Sur-Seine, France"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1861","DOI":"10.1177\/0363546515621554","article-title":"Risk of secondary injury in younger athletes after anterior cruciate ligament reconstruction: A systematic review and meta-analysis","volume":"44","author":"Wiggins","year":"2016","journal-title":"Am. 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