Arytenoid Cartilage Dislocation: A 20-year Experience

Summary

Arytenoid cartilage dislocation is an infrequently diagnosed cause of vocal fold immobility. Seventy-four cases have been reported in the literature to date. Intubation is the most common origin, followed by external laryngeal trauma. Decreased volume and breathiness are the most common presenting symptoms. We report on 63 patients with arytenoid cartilage dislocation treated by the senior author (RTS) since 1983. Significantly more posterior than anterior dislocations were represented. Although reestablishing joint mobility is difficult, endoscopic reduction should be considered to align the heights of the vocal processes. This process may result in significant voice improvement even long after the dislocation. Strobovideolaryngoscopy, laryngeal electromyography, and laryngeal computed tomography (CT) imaging are helpful in the evaluation of patients with vocal fold immobility to help distinguish arytenoid cartilage dislocation from vocal fold paralysis. Familiarity with signs and symptoms of arytenoid cartilage dislocation and current treatment techniques improves the chances for optimal therapeutic results.

Introduction

Vocal fold immobility or hypomobility can result from injury to the recurrent or superior laryngeal nerve, or from a laryngeal structural problem, such as arytenoid cartilage dislocation or cricoarytenoid joint fixation. Accurate diagnosis is critical to devising the optimal therapeutic approach. Arytenoid cartilage dislocation or subluxation is diagnosed infrequently, but it may be mistaken easily for vocal fold paralysis or paresis. If the otolaryngologist is not considering the diagnosis, he or she will probably miss it. Early diagnosis and treatment are more likely to reestablish or improve joint mobility; however, previous reports have demonstrated that a good voice result can be obtained even with late surgical intervention.1, 2

The cricoarytenoid joint is diarthrodial, with a synovium-lined capsule. It is formed by the articulation of the pyramidal-shaped arytenoid cartilage and the elliptical cricoid facet. The intrinsic forces from attached laryngeal muscles and ligaments provide support to the joint. The joint axis lies approximately at a 45° angle from the sagittal plane and a 40° angle from the horizontal plane.1, 3 Although traditional teaching describes cricoarytenoid joint motion as a combination of rotating, gliding, and rocking,⁴ its movement is more complicated. This complex mechanism controls abduction and adduction of the true vocal folds and is, therefore, critical for protection of the airway and phonation.