In Vitro Mechanical Testing of an Alternate Laryngoplasty System(ALPS) for Horses

Abstract

Mechanical evaluation of a novel alternate laryngoplasty system (ALPS). Experimental. Cadaveric horse larynges (n = 10). Arytenoid and cricoid cartilages were embedded for testing. A novel laryngoplasty system consisting of a metallic anchor, 2 stands of #2 suture material, and a metallic button were evaluated. A traditional laryngoplasty using a single strand of #5 Ethibond was evaluated in parallel. Constructs were evaluated in cyclic testing oscillating from 30 to 50 N for 3600 cycles. Constructs subsequently underwent a single cycle to failure. Distraction during cyclic testing was recorded. Load at failure and stiffness were calculated from single-cycle failure testing. There was no difference in mean arytenoid single-cycle load-to-failure for the Ethibond (206.9 ± 13.1 N) constructs compared with ALPS (220.6 ±17.1 N) constructs (P = .486). In the cricoid under single-cycle testing, the ALPS (236.0 ± 23.4 N) constructs were significantly stronger than the Ethibond (161.5 ± 12.2 N) constructs (P = .013). The combined distraction was significantly greater for Ethibond (6.29 ± 1.24 mm) constructs compared to the ALPS (3.43 ± 0.28 mm) constructs (P = .033). The ALPS construct was stiffer and at least as strong as the traditional laryngoplasty construct in single cycle failure in both the arytenoid and cricoid cartilages. Combined distraction was significantly reduced using the ALPS compared to the traditional laryngoplasty in vitro under cyclic testing.