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Updated: Apr 19, 2026

Surgical Retrieval, Isolation and In vitro Expansion of Human Anterior Cruciate Ligament-derived Cells for Tissue Engineering Applications
Published on: April 30, 2014
A Randomized Clinical Trial Comparing Patellar Tendon, Hamstring Tendon, and Double-Bundle ACL Reconstructions:
Nicholas Mohtadi1, Denise Chan, Rhamona Barber
1*Sport Medicine Centre, University of Calgary, Calgary, Alberta; †Department of Surgery, Faculty of Medicine and the Sport Medicine Centre, University of Calgary, Calgary, Alberta; and ‡Departments of Surgery & Community Health Sciences, Faculty of Medicine, Health Sciences Centre. Foothills Campus, University of Calgary, Calgary, Alberta.
Objective:
To compare 3 anatomically positioned autografts for anterior cruciate ligament (ACL) reconstruction, by measuring patient-reported disease-specific quality of life at 2 years postoperatively.
Design:
Double-blinded, randomized clinical trial with intraoperative computer-generated treatment allocation. Patients and an independent trained evaluator were blinded.
Setting:
University-based orthopedic referral practice.
Patients:
Three hundred thirty patients (14-50 years; 183 male patients) with isolated ACL deficiency were equally randomized to: (1) patellar tendon, PT: 28.7 years (SD = 9.7); (2) quadruple-stranded hamstring tendon, HT: 28.5 years (SD = 9.9); and (3) double bundle using HT, DB: 28.3 years (SD = 9.8); 322 patients completed 2-year follow-up.
Intervention:
Anterior cruciate ligament reconstruction using PT, HT, or DB autografts.
Main Outcome Measures:
Measured at baseline, 1 and 2 years postoperatively-primary: anterior cruciate ligament quality-of-life scores; secondary: International Knee Documentation Committee (IKDC) scores, KT-1000 arthrometer, pivot shift, range of motion, Tegner activity, Cincinnati Occupational Scale, and single-leg hop. Proportions of correct graft type guesses by the patients and evaluator assessed blinding effectiveness.
Results:
Baseline characteristics were not different. Anterior cruciate ligament quality-of-life scores increased over time for all groups (P = 0.001) but were not different at 2 years (P = 0.591): PT = 84.6 (SD = 16.6, 95% confidence interval [CI] = 81.4-87.8), HT = 82.5 (SD = 17.7, 95% CI = 79.2-85.9), and DB = 82.4 (SD = 17.5, 95% CI = 79.1-85.7). Two-year KT-1000 side-to-side differences (PT = 1.86 mm; HT = 2.97 mm; DB = 2.65 mm) were statistically significant between PT-HT (P = 0.002) and PT-DB (P = 0.044). The remaining secondary outcomes were not statistically different. Correct graft type guesses occurred 51% of the time for patients and 46% for the evaluator.
Conclusions:
Two-year disease-specific quality-of-life outcome was not different between the ACL reconstruction techniques. The PT reconstructions had significantly lower side-to-side differences on static stability measures. Patient and evaluator blinding was achieved.
Level Of Evidence:
Level 1 (Therapeutic Studies).
Clinical Relevance:
This high-quality, large, double-blind randomized clinical trial (RCT) addresses the insufficient evidence in the literature comparing PT, single-bundle hamstring, and DB hamstring reconstructions for ACL rupture in adults. In addition to the clinical and functional results, this RCT uniquely reports on the disease-specific, patient-reported quality-of-life outcome at 2 years postoperatively.

