Preliminary clinical study of the arytenoid cartilage abduction grades after prosthetic laryngoplasty with cricoarytenoideus dorsalis myectomy in racehorses.

Abstract

OBJECTIVE: To assess the clinical impact of the cricoarytenoideus dorsalis (CAD) myectomy in the short- and long-term postoperative abduction grade in racehorses. METHODS: Records from horses presented for surgical treatment of recurrent laryngeal neuropathy from January 2019 through December 2023 were divided into 2 groups: horses that received standard prosthetic laryngoplasty and horses that received a complete myectomy of the CAD (modified myectomy laryngoplasty). Outcomes were compared through endoscopic evaluation after anesthetic recovery, both short term (7 to 10 days) and long term (80 to 90 days). A retrospective review of clinical records was conducted, supplemented by a telephone questionnaire, designed to assess athletic performance and return to racing. RESULTS: There was a significantly higher grade of recurrent laryngeal neuropathy among older horses (4 to 5 years) compared to younger horses (2 to 3 years) at presentation. Age, however, did not influence the long-term outcomes. The modified myectomy laryngoplasty group exhibited significantly better long-term endoscopy grades, with 62.6% maintaining grade 2 abduction and superior grade retention (mean, 2.38) compared to those with PL alone (mean, 3.13). CONCLUSIONS: Results support the hypothesis that removing the CAD muscle during surgery will minimize the dynamic impact to the prosthesis postoperative and decrease the likelihood of early and long-term loss of arytenoid abduction. CLINICAL RELEVANCE: Clinical findings can serve as reference point for future research to quantify the impact of CAD muscle in the loss of arytenoid abduction post operative in racehorses.