Abstract
Abstract
Objectives
To evaluate mechanical properties of three suture-tendon constructs, the Krackow stitch (KS), the modified Prusik knot (PK) and the Locking SpeedWhip (LSW), using human cadaveric quadriceps grafts (QT).
Methods
Thirty QT grafts were obtained from human cadaver specimens and an equal number of tendon-suture constructs were prepared for three stitches: KS, PK and LSW. The constructs were mounted in a materials testing machine (ElectroPuls E10000, Instron, Norwood, MA) and subject to tensile loading based on an established protocol. Load and displacement data for each tendon-suture construct were recorded.
Results
Seven of 10 LSW specimens failed due to suture pullout before completing cyclic loading. Comparisons of the 3 successful LSW specimens (LSW3) were made to the KS and PK groups. All KS and PK specimens failed by suture breakage in load to failure stage. PK and LSW3 showed greater elongation after pretensioning than KS (7.29 ± 2.05, 7.05 ± 0.70, and 5.39 ± 0.95 mm respectively, p = 0.016 and p = 0.018). PK, LSW, and LSW3 showed greater elongation after preload than KS. Peak loads of PK (316.16 ± 18.31N), KS (296.00 ± 18.73N), and LSW (227.43 ± 76.20 N) were significantly different; LSW3 (319.33 ± 9.39 N) was not different from any group. KS was stiffer than PK (97.19 ± 8.03 vs 84.53 ± 6.72 N/mm, p = 0.0012). No differences were seen between the groups for elongation after cyclic loading or cross-sectional area.
Conclusions
KS is the better of the sutured methods based on elongations and less risk of suture pullout. Excessive tendon tearing may initiate in the range of 100–200N with the LSW technique. PK provides similar performance to LSW and LSW3 in terms of elongations, but has the advantage of faster preparation time and less cost of the needle.
Declaration of Interest
(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.