Mechanical Comparison of 3 Anchoring Techniques in the Muscular Process for Laryngoplasty in the Equine Larynx

Objective To compare mechanical properties of 2 techniques with a conventional technique for anchoring the muscular process in a laryngoplasty procedure. Study design Experimental ex vivo study. Sample Population Equine larynges (n = 60). Methods A single loop (SL), a screw (SC), and a double loop technique (DL) were compared. Constructs were subjected to cyclic loading, oscillating from 5 to 50 N for 3000 cycles, followed by a single cycle to failure test. Mean distraction, load at failure, stiffness, and failure mode were compared between groups. Results Mean ± SD distraction in cyclic loading was greater for DL (2.1 ± 0.7 mm) than for SL (1.9 ± 1.3 mm) and SC (1.539 ± 0.9 mm); however, there was no significant difference between SL and SC or between SL and DL. Mean ultimate failure load was greater for DL (240 ± 44.56 N) than for SC (189.59 ± 46.16 N) and SL (150.93 ± 44.43 N) and greater for SC compared with SL. Failure occurred by cartilage tearing for DL and SL, and by screw pull out (n = 13) or knot slippage (4) for SC. Conclusion In cyclic loading, SC is more stable than DL and at least as stable as SL. In single cycle to failure, DL is the strongest construct and SC is stronger than SL.