Biomechanical performance of traditional arthroscopic knots versus slippage-proof knots.

PURPOSE

To compare the biomechanical, time, and profile characteristics of a new sliding locking knot termed the slippage-proof knot (SPK) and a modified slippage-proof knot (MSPK) with those of traditional arthroscopic knots.

METHODS

We evaluated the Samsung Medical Center (SMC) knot, Revo knot, SPK, and MSPK (an SPK with a single added half-hitch) tied with high-strength suture, with 11 trials of each cycled 1,000 times between 10 and 45 N and then loaded to failure. Total displacement during cyclical testing, maximal load to failure, and mode of failure were recorded for each knot. We also measured the dimensions of the knots and the time required to tie each knot.

RESULTS

On load-to-failure testing, no difference in strength was found between the SMC and Revo knots (P = .082). The Revo knot and MSPK were also of equivalent strength (P = .183), and the SMC knot was 11% stronger than the MSPK (P = .017). All 3 of these knots were stronger than the SPK. On cyclical testing, the SMC knot, Revo knot, and MSPK allowed equivalent total displacement and allowed statistically less total displacement than the SPK. All SMC knots, Revo knots, and MSPKs failed by suture breakage, whereas the SPKs all slipped at failure. We found that the SPKs and MSPKs are tied more quickly than traditional knots. The SPK and MSPK dimensions are wider yet shorter than those of the other knots in the study.

CONCLUSIONS

Our results indicate that the MSPK has biomechanical properties comparable to the SMC and Revo knots despite only requiring 1 added half-hitch, whereas the SPK was found to be significantly inferior to the other knots tested. We found that the slippage-proof knots (SPK and MSPK) were tied more quickly and have shorter, wider profiles than traditional knots.

CLINICAL RELEVANCE

The MSPK has knot security comparable to the SMC and Revo knots while requiring only 1 added half-hitch, and it may be most beneficial in cases in which a large number of knots will be tied because the fewer required half-hitches reduces the surgical time without reducing its biomechanical properties.