A modified laryngoplasty approach promoting ankylosis of the cricoarytenoid joint.

The research involved a modified operation procedure on horses aimed at causing ankylosis (fusion) of the cricoarytenoid joint in the larynx, and testing the stability of the part in an abducted position. The study confirmed that this modified approach can promote ankylosis and helps in reducing the loss of abduction of the arytenoid.

Objective, Methodology, and Participants

• The goal of this research was to implement a modified laryngoplasty procedure that would lead to ankylosis of the cricoarytenoid (CA) joint and evaluate the stability provided to an abducted arytenoid in vitro (outside the body).
• To compare the results, the team assigned horses either to a control laryngoplasty group (3 horses) or to the modified laryngoplasty group (5 horses).

Procedures, Evaluation, and Data Analysis

• Post-surgery, endoscopic upper airway evaluations were conducted to measure quotients on the first day and three months later. These quotients are used to assess whether abduction is maintained.
• The horses were euthanized three months post-surgery for a further collection of larynges and detailed analysis. The larynges were then used to measure translaryngeal impedance and for the histologic evaluation of the CA joint ankylosis.
• Each specimen of larynges was subjected to increasing negative pressure while keeping the sutures intact or cut. This allowed for a detailed analysis of translaryngeal impedance changes.
• Analysis of Variance (ANOVA) was the statistical method used for the data, with significant changes defined by a P-value less than 0.05.

Results

• At the three-month mark, the control group showed a higher loss of left arytenoid cartilage abduction than the modified laryngoplasty group.
• The data showed significantly lower impedance for the modified laryngoplasty group compared to the control group, and even lower when the sutures remained intact rather than being cut.
• Microscopic examination confirmed fibrous bridging of the left CA joints in the modified laryngoplasty group, revealing successful ankylosis.

Conclusion

• The results affirmed the initial hypothesis, proving that a modified laryngoplasty approach promotes ankylosis of the CA joint and decreases the loss of abduction of the arytenoid, thus offering a potential new solution for related health issues in horses.