Evaluation of Tibial Fixation Devices for Quadrupled Hamstring ACL Reconstruction

Abstract

Background: Shortcomings to tibial-side fixation have been reported as causes of failure after anterior cruciate ligament reconstruction. Adjustable-loop suspensory devices have become popular; however, no comparison with hybrid fixation (ie, interference screw and cortical button) exists to our knowledge. Purpose: The purpose of this study was to compare the biomechanical properties of adjustable loop devices (ALDs) in full-tunnel and closed-socket configurations in relation to hybrid fixation. We hypothesized that primary stability of fixation by a tibial ALD will not be inferior to hybrid fixation. Study Design: Controlled laboratory study. Methods: Tibial fixation of a quadrupled tendon graft was biomechanically investigated in a porcine tibia–bovine tendon model using 5 techniques (n = 6 specimens each). The tested constructs included hybrid fixation with a cortical fixation button and interference screw (group 1), single cortical fixation with the full-tunnel technique using an open-suture strand button (group 2) or an ALD (group 3), or closed-socket fixation using 2 different types of ALDs (groups 4 and 5). Each specimen was evaluated using a materials testing machine (1000 cycles from 50-250 N and pull to failure). Force at failure, cyclic displacement, stiffness, and ability to pretension the graft during insertion were compared among the groups. Results: No differences in ultimate load to failure were found between the ALD constructs (groups 3, 4, and 5) and hybrid fixation (group 1). Cyclic displacement was significantly higher in group 2 vs all other groups ( P < .001); however, no difference was observed in groups 3, 4, and 5 as compared with group 1. The remaining tension on the construct after fixation was significantly higher in groups 3 and 4 vs groups 1, 2, and 5 ( P < .02 for all comparisons), irrespective of whether a full-tunnel or closed-socket approach was used. Conclusion: Tibial anterior cruciate ligament graft fixation with knotless ALDs achieved comparable results with hybrid fixation in the full-tunnel and closed-socket techniques. The retention of graft tension appears to be biomechanically more relevant than tunnel type. Clinical Relevance: The study findings emphasize the importance of the tension at which fixation is performed.

Strategies to promote tendon-bone healing after anterior cruciate ligament reconstruction: Present and future

“…At present, interference screws are often used to fix the transplanted tendon. However, the application of interfering screws has been found to be associated with complications ( Xu et al, 2021 ; Ammann et al, 2022 ). Therefore, for patients at risk of poor tendon-bone union, the fixation strategy needs to be optimized for optimal clinical benefit.…”

“…Therefore, in order to avoid the influence of these factors on tendon transplantation, a variety of clinical measures should be taken, including the use of magnesium based interference screw to fix the transplanted tendon, moderate postoperative rehabilitation training, etc. ( Ammann et al, 2022 ). Therefore, only attention to the above influencing factors can ensure the perfect fusion of the transplanted tendon in the bone tunnel, so as to enable patients to recover the knee function earlier and faster ( Woo et al, 2004 ).…”

The tibial tunnel drilling angles of 60° provided a lower ultimate load to failure on a single bundle posterior cruciate ligament graft using interference screw fixation compared to 30°/45°

“…Thirty‐six skeletally mature porcine tibias from the swine hindlimbs and 30 bovine extensor digitorum tendons were used in this study. This model has been frequently selected because of the human knee showed similarities with the porcine knee, and the bovine extensor digitorum tendons also showed properties similar to those of human hamstring tendons [3, 9, 16]. Specimens were harvested from a local slaughterhouse immediately after killing.…”

Meniscal resection increases the risk of residual knee laxity even in patients undergoing anatomic double-bundle anterior cruciate ligament reconstruction with eight strands of hamstring autografts

“…ACL reconstruction (ACLR) is a commonly used surgical procedure for the treatment of ACL deficiency, with continually updated reconstructive concepts and surgical techniques [3, 4]. Many studies have compared the outcomes of different surgical techniques regarding the graft source, graft type, tunnel placement, tunnel creation, graft tensioning, and graft fixation [5–9]. The subjective and objective outcomes are also associated with surgical timing, preoperative instability, meniscal treatment, rehabilitation protocols, and athletic levels [10–14].…”