Abstract
Abstract
Objectives
ACL graft-suture fixation can be constructed with needle or needleless techniques. Needleless techniques have advantages of decreased injury, preparation time and cost. The Nice Knot (NK) is common among upper extremity procedures; however, its efficacy in ACL reconstruction relative to other needleless methods is not well known. The purpose of this study was to biomechanically compare quadriceps tendon (QT) grafts prepared with the NK versus the modified Prusik Knot (PK).
Methods
Twenty QT grafts were harvested from 10 embalmed human cadaver specimens. 10 were prepared with the PK and 10 with the NK using a No.2 FiberWire (Arthrex, Naples, FL). The prepared grafts were then mounted in a materials testing machine (ElectroPuls E10000, Instron, Norwood, MA) and subjected to tensile loading based on an established protocol. Each tendon-suture specimen was preconditioned with 3 cycles of 0–100N at 1Hz followed by a constant load of 50N for 1 minute and cyclic loading of 200 cycles from 50–200N at 1Hz and then loaded to failure at a displacement rate of 20mm/min. Load and displacement data for each tendon-suture construct was recorded by the testing machine.
Results
The average age of the donors was 89.1 ± 8.6 years. The NK showed significantly smaller elongations after pre-tensioning (p < 0.01), preloading (p < 0.001), and cyclic loading (p < 0.001). Peak load was greater for the PK than the NK (p = 0.047). No significant differences were seen for stiffness (p = 0.41) or cross-sectional area (p = 0.22).
Conclusions
The results of this biomechanical study show that the NK constructs provide less elongation than the PK constructs but with similar stiffness. The NK offers an alternative option for needleless ACL graft preparation technique.
Declaration of Interest
(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.