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

Abstract

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.

Keywords: knee; meniscus root; pull‐out repair; root tear; slip‐knot.

Figure 1

Schematic illustrations and corresponding images of the four meniscus‐suture configurations in this study. (a) Two simple‐suture (TSS) configuration, (b) two slip‐knot (TSK) configuration, (c) two modified Mason–Allen (TMMA) configuration, and (d) two Cinch‐Loop (TCL) configuration.

Figure 2

A detailed step‐by‐step illustration of the slip‐knot technique. (a, b) Creating a half‐hitch loop at the middle of the suture first; (c) the working limb pierces through the meniscus from underneath and passes through the half‐hitch loop to form a slipped knot (d). (e) By pulling on the working limb, the knot then slides and tightens onto the meniscus. (f) Final construct.

Figure 3

The biomechanical testing set‐up.

Figure 4

Representative of the load–displacement curve. The stiffness was calculated as the slope of the red dashed line.

Figure 5

This box plot depicts the displacement observed during cyclic loading at 100, 500, and 1000 cycles. Overhead bars represent statistically significant interconstruct comparison (p < 0.05). TCL, two cinch‐loop; TMMA, two modified Mason‐Allen; TSK, two slip‐knot; TSS, two simple‐suture.

Figure 6

This box plot displays the yield load (a) and displacement at yield load (b). Overhead bars represent statistically significant interconstruct comparison (p < 0.05). TCL, two cinch‐loop; TMMA, two modified Mason–Allen; TSK, two slip‐knot; TSS, two simple‐suture.

Figure 7

This box plot displays the ultimate failure load (a) and displacement at ultimate failure load (b). Overhead bars represent statistically significant interconstruct comparison (p < 0.05). TCL, two cinch‐loop; TMMA, two modified Mason–Allen; TSK, two slip‐knot; TSS, two simple‐suture.