Three-dimensional motion of the arytenoid adduction procedure in cadaver larynges.

To determine whether variation in suture placement could improve the results of the arytenoid adduction procedure, a model was developed using fresh human cadaver larynges. Three-dimensional (3-D) motion of the arytenoid was determined by utilizing computed tomographic imaging with radiopaque markers on the apex and muscular and vocal processes. By utilizing principles previously applied to the study of rigid body mechanics for the carpal, knee, and tarsal joints, rotation and translation of the arytenoid about the axial, coronal, and sagittal axes were calculated. Subglottic airflow resistance was measured before and after the procedure. Posterior glottic closure was reproducibly achieved, as determined by computed tomographic imaging and airway resistance. Conflicting reports on cricoarytenoid joint mechanics can be attributed to reliance on trigonometric analysis of two-dimensional images, which results in errors in out-of-plane motion. This paper presents a useful model for obtaining detailed anatomic information describing arytenoid 3-D motion.