The anatomy and movements of the cricoarytenoid joint.

The cricoarytenoid joints of 45 larynges were dissected and examined with respect to ligaments, articulating surfaces and movements. In this study the capsule of the joint was uniformly thin, and was strengthened by a superficial, medially placed, flattened band of fibers of one or two strata, known as the posterior cricoarytenoid ligament. Three movements of the arytenoid cartilage at this joint were found, the axes and ranges of which were directly related to the shape and position of the cricoid facet. Notwithstanding these differences, the positions of all the vocal folds in extreme adduction or abduction were similar. These findings contradict the traditional concepts of uniformity of the anatomy and movements of the cricoarytenoid joint and also the position and therefore name, of the "posterior" cricoarytenoid ligament.