ISAKOS: 2023 Congress in Boston, MA USA

2023 ISAKOS Biennial Congress ePoster

 

Comparable Primary Stability Between Current-Generation Adjustable Loop Cortical Buttons for Anterior Cruciate Ligament Reconstruction – A Biomechanical Study

Adrian Deichsel, MD, Münster, NRW GERMANY
Lara Leibrandt, cand. med., Münster, NRW GERMANY
Michael J. Raschke, MD, Prof., Münster GERMANY
Matthias Klimek, M. Sc., Muenster GERMANY
Jens Wermers, MD, Münster GERMANY
Christian Peez, MD, Münster, NRW GERMANY
Thorben Briese, MD, Münster GERMANY
Elmar Herbst, MD, PhD, Muenster GERMANY
Christoph Kittl, MD, MD(res), Muenster GERMANY
Johannes Glasbrenner, MD, Münster GERMANY

Department for Trauma-, hand- and reconstructive surgery, university hospital Münster, Münster, NRW, GERMANY

FDA Status Cleared

Summary

Contemporary adjustable loop cortical buttons do not show significant differences in primary stability, attributable to implant design and in comparison to a fixed loop cortical button, and can therefore be safely used for ACL reconstruction.

ePosters will be available shortly before Congress

Abstract

Introduction

Previous generations of adjustable loop buttons (ALB) showed increased construct elongation under cyclic loading, which might lead to construct failure of anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to compare contemporary versions of ALB regarding their biomechanical primary stability and to compare them to a fixed suture loop (FSL) construct.

Methods

In a porcine model of ACL reconstruction, superficial porcine flexor tendons were looped to a diameter of 8 mm and fixed with three different ALB and one FLB (each n = 10) in an 8 mm bone tunnel in porcine tibiae. Implants used were:
1. Infinity™ Button (ConMed, Utica, New York) = Chinese finger trap 1 (CFT1)
2. Tightrope® II RT (Arthrex, Naples, Florida) = Chinese finger trap 2 (CFT2)
3. A-TACK (Karl Storz, Tuttlingen, Germany) = Locked suture loop (LSL)
4. FlippTack (Karl Storz, Tuttlingen, Germany) = Fixed suture loop (FSL)
Cyclic loading for 1000 cycles from 0 to 250 N was applied utilizing an uniaxial testing machine (model Z005, Zwick/Roell, Ulm, Germany), followed by load to failure testing. Elongation, Load to failure, stiffness, and yield load of the tested constructs was determined.

Results

After 1000 cycles at 250 N Elongation was 5,0 mm ± 0,8 in the CFT1 group, 4,4 mm ±0,4 in the CFT2 group, 4,9 mm ±1,0 in the LSL group, and 4,8 mm ± 0,8 in the FSL group. No significant differences between the groups were observed. Load to failure was 797 N ± 70 in the CFT1 group, 853 N ±111 in the CFT2 group, 752 N ±129 in the LSL group, and 830 N ± 80 in the FSL group. No significant differences between the groups were observed. Yield load was 570 N ± 25 in the CFT1 group, 563 N ±71 in the CFT2 group, 562 N ±53 in the LSL group, and 560 N ± 57 in the FSL group. No significant differences between the groups were observed.

Conclusion

Contemporary ALB devices do not show significant differences, attributable to implant design and in comparison, to a FSL device. Therefore, regarding biomechanical properties, all tested implants can be used for ACLR.