- Cricothyroid articulation
Cricothyroid articulation The cartilages of the larynx. Latin articulatio cricothyroidea
The cricothyroid articulation (or joint) is a joint connecting the cricoid cartilage and the thyroid cartilage. It plays a key role in adjusting human voice pitch by changing the tension of the vocal cords. This tension is controlled mostly by the endolaryngeal vocalis and the extralaryngeal cricothyroid muscles which change vocal fold tension by narrowing the cricothyroid space created by rotation and gliding movements in horizontal and vertical direction allowed for by the cricothyroid articulation.
Three types A, B, and C have been identified.
Type A is found in 56% of females and 66% of males. There is a well-defined "facet". It has a tight capsule and ligaments with either a concavity or a small groin directed from posterior superior to anterior inferior. Horizontal translational movement is about 3.0 mm, vertical gliding about 2.5 mm with great movement horizontally than vertically. The gliding movements are smaller in males than in females . Type B is in 24$ of females and 20% of males. In contrary to type A it lacks a definite "facet" and the two cartilaginous parts of the articulation are joined only by soft connective tissue. Horizontal movement is 5.0 mm and vertical, 5.1 mm with no differences between them.
Type C concerns all others and has a flat surface with or without a tiny protuberance. Horizontal movement is about 5.1 mm, and vertical 3.8 mm.
Type A is less mobile than the other two.
Joints and ligaments of head and neck (TA A03.1.03–08, GA 3.287) Temporomandibular Atlanto-occipital
anat(h/c, u, t, l)/phys
noco(arth/defr/back/soft)/cong, sysi/epon, injr
proc, drug(M01C, M4)
Head and neck anatomy, Upper RT: Larynx (TA A06.2, TH H3.05.01, GA 11.1072) Cartilages Ligaments/folds· lower: Cricothyroid ligament (Median, Lateral/Conus elasticus, Vocal ligament/Vocal folds) Laryngeal cavity Other
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