Micro-CT visualization of the cricothyroid joint cavity in cadavers

Objectives/Hypothesis: To directly visualize the cricothyroid joint (CTJ) cavity of the human cadaver and to correlate the appearance of the CTJ cavity to its fibrous capsule. Study Design: Prospective. Methods: Twenty‐five cadavers (nine females and 16 males; age range, 67–95 years) were used for gross anatomy, micro‐computed tomography (CT) arthrography, histology, E12 sheet plastination, and magnetic resonance imaging examinations. The cadavers were donated for the purposes of teaching and research under the Human Tissues Act. Results: Using micro‐CT arthrography with intra‐articular filling and sheet plastination technique, this study demonstrated that the dimension of the CTJ cavity was much larger than that of the articular surfaces, particularly at the superior and anterior aspects of the joint. Connective tissue fibers were regularly orientated and significantly strengthened in the posterior and inferior aspects of the CTJ capsule. Such fibrous configuration appeared to enhance the strength of the capsule itself rather than to shorten the distance between the articular surfaces. The size of the direct contact area of the opposing articular surfaces varied significantly between the sides of the same subject and among individuals. Conclusions: This study supports the general view that the cricoid cartilage rotates in a visor‐like fashion on the inferior cornu of the thyroid cartilage. However, the pivot for the CTJ rotation appears wobbly. The wobbly pivot may increase the joint mobility as the rotation allows the horizontal and vertical gliding movements of the CTJ.