Evaluating different closed loop graft preparation technique for tibial suspensory fixation in ACL reconstruction using TightRope™

Abstract

In most anterior cruciate ligament (ACL) reconstructions, grafts are fixed to the femoral side first followed by the tibial side. Various techniques have been reported to achieve optimal tension on the grafts, but once the grafts are fixed it is difficult to adjust graft tension further. To enable post fixation tension control we have invented a new graft configuration using an adjustable loop-device (TightRopeTM, Arthrex, FL, USA) on the tibial side. In this paper, biomechanical properties of this configuration using soft tissue were examined in terms of graft diameter and various suture techniques (referred to as base suture) to make a closed circle to support TightRopeTM.Two experiments were conducted under different conditions. In each experiment, cyclic load, followed by a pull-to-failure load, was applied to the grafts and elongation and failure mode were recorded. (1) To evaluate the effects of diameter, 5.0 or 6.0 mm grafts were prepared by a single locking loop stitch as the base suture (SLL5, SLL6). (2) To evaluate different base sutures, 5.0 mm tendons were used, and grafts were prepared using five kinds of base sutures (SLL, ZLL: zigzag locking loop, DZLL: double zigzag locking loop, DK: double Krackow, DK w/o TR: double Krackow without TightRopeTM). In the first experiment, tearing was observed in 2 of 6 cases in the SLL5 test group, whereas no tearing was observed with SLL6. In the second experiment, no tearing was observed with DZLL or DK. Elongation was smaller in these two groups compared to the other groups. Mechanical strength decreases with a smaller graft diameter. Biomechanical properties differed with different base sutures and, among them, the double-zigzag-suture stitch and double Krackow provided less elongation and higher ultimate load in this graft configuration.

Randomized comparative study of suspension femoral fixation device in graft position maintenance in anterior cruciate ligament reconstruction: EndoButton CL vs TightRope RT

“…We hypothesized that this was mostly due to surgical technique in which grafts were re-tensioned when any laxity was observed arthroscopically after 10 passive flexion-extension knee motions at the final step of the reconstruction. 18 This lessened the initial elongation.…”

“…Either EB or TR was used for the femoral fixation device and TR was used as the tibial fixation device in all the cases according to previously reported graft configuration. 18 The initial graft tension was applied manually while arthroscopically verifying the tension of the graft. After the initial fixation of the graft, the knees were passively extended and flexed from 0 to 90° ten times to reveal loss of initial tension that would occur with the beginning of early-phase rehabilitation.…”

An Efficient Needleless Grasping Suture Technique for Graft Preparation in Anterior Cruciate Ligament Reconstruction

“…Therefore, the weave of the tendon ends seemed just to take effect of an easy pass through the tunnel and as strings to keep tension. Traditionally, the ends were weaved using the needle suture ( 16 ). However, it was time-consuming, laborious, and required skill.…”

“…Considering the role of the weave, a less time-consuming, simpler, but a firmly fixed method can be used. Sasho et al ( 16 ) tested the mechanical strength of tendon graft samples by employing different suture techniques of joining the two free ends. They found that the ultimate load was the highest in the double zigzag locking loop stitch group (558.7 ± 47.6 N), but a statistically significant difference was not observed among the groups.…”

A biomechanical comparison of all-inside cruciate ligament graft preparation techniques

“…While various graft fixation constructs have been studied in depth (Fabbri et al, 2016 ; Lubowitz, 2012 ; Fritsch et al, 2017 ; Sasho et al, 2018 ; Tiefenboeck et al, 2018 ), current biomechanical literature falls short in offering relative comparisons between graft preparation techniques. Although the quadrupled graft preparation technique is the preferred method of graft preparation, multiple techniques have been described (Lubowitz, 2012 ; Fritsch et al, 2017 ; Sasho et al, 2018 ; Tiefenboeck et al, 2018 ; McCarthy et al, 2012 ). Additionally, insufficient tendon length can become a problem for ACL reconstruction in petite patients or in the case of inadvertent amputation of a tendon during harvest, such as in the setting of previous surgery and resultant scar.…”