In vitro acute load to failure and eyelet abrasion testing of a novel veterinary screw-type mini-anchor design.
OBJECTIVE
To determine acute load to failure (ALF) and suture abrasion (SA) at 0° and 90° for a novel screw-type mini-anchor design.


METHODS
Biomechanical in vitro study.


METHODS
Synthetic bone.


METHODS
Twenty mini-anchors were inserted into synthetic bone blocks assigned to 1 of 2 groups (0° ALF, 90° ALF). Pullout was performed at 5 mm/min. ALF, yield strength and stiffness were calculated. SA constructs were created with 4 groups of 5 anchors each with either 30 lb nylon leader line (NLL), 40 lb NLL, #2 Fiberwire or #5 Fiberwire. SA was performed at 0° and 90° with a sinusoidal wave form at 0.5 Hz and 10 N load for 1000 cycles or until failure. Data were summarized as mean ± SD. ALF data were analyzed using t-tests. SA data were analyzed using log rank, Tukey-adjusted pairwise comparisons and sign tests. Significance was set at P = .05.


RESULTS
Mean ± SD ALF at 0° and 90° was 431.8 ± 70.8 N and 683 ± 48.7 N, respectively. 90° ALF was significantly higher. Yield strength and stiffness were not significantly different at 0° and 90°. #5 and #2 Fiberwire survived significantly more cycles than 40 lb and 30 lb NLL at 90°. At 0°, 30 lb NLL survived significantly less cycles than either Fiberwire size. Suture orientation did not have a significant effect on SA for Fiberwire constructs.


CONCLUSIONS
The novel mini-anchor has ALF comparable to other mini-anchors. Fiberwire survived more cycles in the novel anchor eyelet than NLL and FW suture orientation in the eyelet did not affect SA.
South Carolina Veterinary Specialists-Surgery, Columbia, South Carolina, USA. karkdvm@hotmail.com
Kevin A R
KA
Kunkel
Roy J
RJ
Rusly
R Randy
RR
Basinger
John D
JD
DesJardins
Patrick D
PD
Gerard
D000818:Animals; D001696:Biomechanical Phenomena; D001863:Bone Screws / Q000592:standards / Q000662:veterinary*; D001842:Bone and Bones / Q000601:surgery; D004868:Equipment Failure; D066298:In Vitro Techniques; D013537:Sutures / Q000592:standards / Q000662:veterinary; D016474:Weight-Bearing