The Effect of Different Combinations of Three Stacked Half-Hitches and Suture Materials on an Arthroscopic Knot in a Dry or Wet Environment.

ABSTRACT

Purpose: Evidence is lacking on the effect of different combinations of three stacked half-hitches and suture materials on the loop/ knot security of an arthroscopic knot under cyclic loading conditions. The specific aim of this study was to identify variables, such as stacked half-hitch configurations, suture materials, and testing environments, that affect knot strength and loop security under cyclic loading conditions. Methods: Two suture materials (Orthocord and ForceFiber) were used to tie five differently stacked reversing half-hitches on alternating posts (RHAP) in an arthroscopic knot condition. All knots were evaluated in both dry and wet cyclic loading tests. Results: Knots tied with three identical half-hitches stacked on the same post (Conf #1) resulted in 100% knot slippage regardless of suture material in dry environment. In the wet environment this knot configuration performed slightly better (ForceFiber 20% survived; Orthocord 40% survived). With knots tied with one of the half-hitches in the RHAPs reversed, a significant improvement occurred in knot holding compared to Conf #1 (p<0.05). Knots tied with the last half-hitches in the RHAPs reversed using ForceFiber were 100% secure in both test environments; whereas those tied with Orthocord had 70% and 80% security rates in the respective environments. Knots tied with two half-hitches of the RHAPs reversed demonstrated the best overall performance. Conclusion: Significant effects for both stacked half-hitch configurations and suture materials on the knot loop and knot security were observed. Caution should be used when tying the 3 RHAPs in a knot using standard arthroscopic techniques. This study may provide a solution that might improve the maximum failure loads observed between orthopaedic surgeons, and achieve better clinical outcomes. Clinical Relevance The findings of this study indicate the importance of three reversing half-hitches on alternating posts in performing arthroscopic knot tying, and provide evidence regarding discrepancies of maximum clinical failure loads observed between orthopaedic surgeons leading to better surgical outcomes.