Clinical Results and Risk Factors for Reinjury 15 Years After Anterior Cruciate Ligament Reconstruction A Prospective Study of Hamstring and Patellar Tendon Grafts

Background: There is a lack of prospective studies comparing the long-term outcome of endoscopic anterior cruciate ligament (ACL) reconstruction with either a patellar tendon or hamstring tendon autograft. Purpose: This prospective longitudinal study compared the results of isolated endoscopic ACL reconstruction utilizing a 4-strand hamstring tendon (HT) or patellar tendon (PT) autograft over a 15-year period with respect to reinjury, clinical outcomes, and the development of osteoarthritis. Study Design: Cohort study; Level of evidence, 2. Methods: Ninety consecutive patients with isolated ACL rupture were reconstructed with a PT autograft, and 90 patients received an HT autograft, with an identical surgical technique. Patients were assessed at 2, 5, 7, 10, and 15 years. Assessment included the International Knee Documentation Committee (IKDC) knee ligament evaluation including radiographic evaluation, KT-1000 arthrometer testing, and Lysholm knee score. Results: Patients who received the PT graft had significantly worse outcomes compared with those who received the HT graft at 15 years for the variables of radiologically detectable osteoarthritis (grade A: 46% in PT and 69% in HT; P = .04), motion loss (extension deficit < 3 degrees: 79% in PT and 94% in HT; P = .03), single-legged hop test (grade A: 65% in PT and 92% in HT; P = .001), participation in strenuous activity (very strenuous or strenuous: 62% of PT and 77% of HT; P = .04), and kneeling pain (moderate or greater pain: 42% of PT and 26% of HT; P = .04). There was no significant difference between the HT and PT groups in overall IKDC grade (grade A: 47% of PT and 57% of HT; P = .35). An ACL graft rupture occurred in 17% of the HT group and 8% of the PT group (P = .07). An ACL graft rupture was associated with nonideal tunnel position (odds ratio [OR], 5.0) and male sex (OR, 3.2). Contralateral ACL rupture occurred in significantly more PT patients (26%) than HT patients (12%) (P = .02) and was associated with age <= 18 years (OR, 4.1) and the PT graft (OR, 2.6). Conclusion: Anterior cruciate ligament reconstruction using ipsilateral autograft continues to show excellent results in terms of patient satisfaction, symptoms, function, activity level, and stability. The use of HT autograft does, however, show better outcomes than the PT autograft in all of these outcome measures. Additionally, at 15 years, the HT graft-reconstructed ACLs have shown a lower rate of radiological osteoarthritis.