Displacement of a Fixed Versus Adjustable Suspensory Fixation Device for Anterior Cruciate Ligament Reconstruction

Suspensory fi xation devices in anatomic anterior cruciate ligament (ACL) reconstruction commonly feature a button that rests on the cortex of the femur, and a loop that holds the graft in position until healing can occur. While this loop can be closed and fi xed in length, some contemporary designs feature a loop that is adjustable. The purpose of this study was to assess the displacement of the fi xed ENDOBUTTONTM CL ULTRA (Smith & Nephew, Inc., Andover, MA, USA) and TightRope® (Arthrex, Inc., Naples, FL, USA) fi xation devices. All loop samples were securely fi xed to a metal plate and axial loading apparatus. Next, a zero to 60N static load was applied to each sample a total of ten times. Following completion of the loading regimen, loop displacement and fi nal distance were measured. Results of this study demonstrated signifi cantly less displacement for the ENDOBUTTON CL ULTRA device vs the TightRope device (0.58mm versus 9.95mm; p < 0.05). Furthermore, the mean distance from the button to the top of the hook for the devices was 8.93mm (ENDOBUTTON) and 14.63mm (TightRope), respectively (p < 0.05). The results of this study suggest that the adjustable TightRope loop can slip and elongate under load after it has been adjusted to its minimum length. It also suggests that ENDOBUTTON CL Ultra may allow for more graft in the femoral tunnel following ACL reconstruction. Vol 03, No 7 July 2012