Impingement Due to Graft Buckling Is more Prevalent after ACL Reconstructions with an Adjustable-Loop compared to a Fixed-Loop
Graft fixation in anterior cruciate ligament (ACL) reconstruction is achieved by interference screws, cortical buttons or combinations of both. The two options for button fixation include a fixed-loop (FL) and an adjustable-loop (AL) device. Both revealed similar clinical outcomes in recent literature, yet reoperation rates have not been studied elaborately. This retrospective cohort study aimed to analyse the reoperation rate, patient reported functional outcome and sensibility disorders after ACL reconstruction using either a fixed-loop or adjustable-loop device.
344 patients underwent primary ACL reconstruction with autologous hamstring tendon grafts. In 189 patients, gracilis and semitendinosus autografts were used with a femoral fixed-loop button fixation (EndoButton, Smith&Nephew) combined with tibial interference screw fixation. In 145 patients a single hamstring autograft was used combined with both femoral and tibial adjustable-loop button fixation (TightRope, Arthrex). Outcome measures were reoperation rate, Lysholm score, Tegner score, International Knee Documentation Committee (IKDC) score and self-reported sensibility disorders.
Median follow-up was 33.0 and 29.0 weeks in the fixed- and adjustable-loop group, respectively. Reoperation rate was comparable between groups (14.8% in FL, 18.6% in AL; p=.353). Analysis of reoperations due to impingement showed an increased incidence of graft buckling in the adjustable-loop group (10% in FL, 75% in AL; p=.013). Mean Lysholm score (83.1 in FL, 81.6 in AL; p=.466), Tegner score (6.2 in FL, 5.8 in AL; p=.153) and IKDC score (81.5 in FL, 79.1 in AL; p=.287) were comparable between groups, as well as the amount of patients reporting sensibility disorders (17.4% in FL, 19.2% in AL; p=.848).
Reoperation rate was comparable between fixed-loop and adjustable loop groups, however the incidence of impingement due to graft buckling was higher in the adjustable-loop group. Fixed- and adjustable-loop devices showed comparable results at final moment of contact in terms of patient-reported functional outcome and self-reported sensibility disorders. Attention should be paid to an even tensioning of all four strands during graft preparation.