Biomechanical study of a new sliding locking knot – “HK-knot”

Abstract

Introduction: A new locking sliding knot (HK-Knot) was developed in the author’s institute. A biomechanical study was performed to compare the properties of HK-Knot with Revo knot, SMC knot and Duncan Loop. Methodology: A total of 80 knots (20 in each group) were tested. All the knots were tied by a single surgeon using No. 2 FiberWire®. The knot was created around two metal bars separated by 10 mm with the help of a single-hole knot pusher. The biomechanical testing protocol of the original paper describing SMC knot was adopted (Kim, 2003). The initial slack in suture loop, average displacement at cyclic loading, load to clinical failure, ultimate load to failure and mode of failure were documented. Results were analyzed using Kruskal-Wallis test and Mann-Whitney U test. Statistical significance was assumed if p<0.05. Result: There was no difference between HK-Knot and SMC knot in both load to clinical failure (98 N versus 99 N) and ultimate load to failure (139 N versus 149 N). The result of the current study compared favourably with the data of SMC knot published by Kim (92 N and 107 N respectively). HK-Knot had the best performance in loop security (0.13 mm, p < 0.001, Kruskal-Wallis test). The average initial slack in Revo knot, SMC knot and Duncan Loop were 0.43 mm, 0.3 mm and 0.17 mm respectively. Discussion and Conclusion: Among all the four knot configurations studied, HK-Knot had the optimal balance between knot strength and loop security.