Satisfactory Clinical Outcomes of Revision Anterior Cruciate Ligament Reconstruction Using Quadriceps Tendon-Patellar Bone Allograft

Background: Allografts are preferred in certain cases of revision anterior cruciate ligament reconstructions to avoid additional graft harvesting and to fill in enlarged tunnels. The clinical outcomes of quadriceps tendon-patellar bone allograft in revision anterior cruciate ligament reconstruction are not well-known. This study was performed to evaluate the clinical outcomes of revision anterior cruciate ligament reconstructions using quadriceps tendon-patellar bone allografts. Methods: Patients who underwent revision anterior cruciate ligament reconstructions with quadriceps tendon-patellar bone allografts with a minimum follow-up of 2 years were retrospectively reviewed. Their mean follow-up length was 33.5 +/- 19.5 months. Outcomes including clinical scores (Lysholm, International Knee Documentation Committee [IKDC], Tegner scale, and Knee injury and Osteoarthritis Outcome Score [KOOS]), knee stability (physical examinations and knee arthrometer), return to sports, and any associated complications were assessed. Degrees of graft synovialization were also evaluated using arthroscopy. Results: A total of 38 patients were reviewed and their age at the time of surgery and follow-up length were 37.2 +/- 12.5 years (range, 17-66 years) and 2.8 +/- 1.6 years, respectively. All clinical scores including KOOS, IKDC, Lysholm, and Tegner scale significantly improved at 2 years after surgery and 92.1% of the patients returned to sports. The mean preoperative side-to-side difference in knee arthrometer decreased from 4.5 +/- 2.3 mm before surgery to 2.6 +/- 1.5 mm after surgery (p < 0.001). Graft synovialization was observed in 13 of 16 patients (81.3%) who underwent second-look arthroscopy. Complication rate was 10.5% (n = 4). All complications were graft re-rupture and occurred at an average of 18 months after revision surgery. Conclusions: Quadriceps tendon-patellar bone allograft showed satisfactory clinical outcomes in revision anterior cruciate ligament reconstruction and thus could be a good alternative when autograft harvesting is not optimal.