Biomechanical Evaluation of Suture Pullout from Canine Arytenoid Cartilages: Effects of Hole Diameter, Suture Configuration, Suture Size, and Distraction Rate

Abstract
Objectiveā€”To evaluate the mechanical properties of canine arytenoid cartilageā€“suture constructs.Study Designā€”Experimental study.Sample Populationā€”Eighty canine cadaveric larynges.Methodsā€”Arytenoid cartilageā€“suture constructs were loaded to failure on a materials testing machine. The effect of hole size, suture configuration, suture size, and rate of distraction on load at failure, displacement at failure, energy to failure, and construct stiffness were evaluated. Polypropylene sutures were used exclusively. Specific variables evaluated were: (1) hole sizeā€”SH needle, 22, 20, and 18 ga hypodermic needles; (2) suture configurationsā€”single dorsal and ventral articular sutures, double sutures, horizontal mattress, locking loop, and single nonā€articular sutures; (3) suture sizeā€”1, 0, 2ā€0, and 3ā€0; and (4) distraction rateā€”0.83 and 36.66 mm/s.Resultsā€”Hole size had no effect on any biomechanical variable. Double suture and horizontal mattress configurations had the highest median load and energy at failure. Single dorsal suture configurations that did not include the arcuate crest had the lowest median load at failure. Larger suture sizes tended to result in stiffer constructs. Cartilageā€“suture constructs behaved in a viscoelastic manner where load at failure, energy at failure, and stiffness increased when distraction rate was increased, whereas displacement at failure did not. Most constructs failed by suture pullout regardless of distraction rate, although 50% of horizontal mattress configurations failed by avulsion of the muscular process.Conclusionā€”Suture and hole sizes appear to have few effects on the biomechanical performance of arytenoidā€“suture constructs. Doubleā€suture and horizontal mattress suture patterns had the best overall mechanical properties for arytenoid lateralization. Singleā€suture techniques, which do not incorporate the arcuate crest, were biomechanically inferior.Clinical Relevanceā€”Cumbersome largeā€diameter sutures offer no advantage over smaller sutures when performing arytenoid lateralization. The crossā€sectional geometry of the muscular process should be taken into account when placing sutures in the arytenoid cartilages. Singleā€suture techniques that do not incorporate the arcuate crest should be avoided.