Biomechanical analysis of four different meniscus suturing techniques for posterior meniscal root pull-out repair: A human cadaveric study

Purpose To compare the biomechanical properties of the slip-knot technique with three other transtibial pullout suture repair constructs for meniscal root tears. Method Thirty-two fresh-frozen cadaveric menisci were randomly allocated to four meniscus-suture fixation constructs: Two simple-sutures (TSS), two slip-knot (TSK) sutures, two cinch-loop (TCL) sutures, and two modified Mason-Allen (TMMA) sutures. Cyclic loading from 5 to 20 N was conducted for 1000 cycles at 0.5 Hz, and then loaded to failure at 0.5 mm/s. Parametric data (displacement during cyclic loading, ultimate load, yield load, and displacement at failure) were analysed using a one-way analysis of variance (ANOVA), whereas nonparametric data (stiffness) were analysed using the Kruskal-Wallis test. Results After 1000 cycles, the TCL construct significantly displaced the most (mean +/- SD, 6.78 +/- 1.32 mm; p < 0.001), followed by the TMMA (2.83 +/- 0.90 mm), TSK (2.33 +/- 0.57 mm), and TSS (2.03 +/- 0.62 mm) groups. On ultimate failure load, there was no significant difference between the TSK group (123.48 +/- 27.24 N, p > 0.05) and the other three groups (TSS, 94.65 +/- 25.33 N; TMMA, 168.38 +/- 23.24 N; TCL, 170.54 +/- 57.32 N); however, it exhibited the least displacement (5.53 +/- 1.25 mm) which was significantly shorter than those of the TCL (11.82 +/- 4.25 mm, p < 0.001) and TMMA (9.53 +/- 2.18 mm, p = 0.03) constructs. No significant difference in stiffness was observed among the four meniscus-suture constructs. Conclusion The slip-knot technique has proven to be a simple, yet robust and stable meniscal root fixation option; moreover, it exhibited superiority over the more complex modified Mason-Allen suture construct in resisting displacement at the ultimate failure load. Level of Evidence Not applicable.