The cricothyroid ligament (also known as the cricothyroid membrane or cricovocal membrane) is a

ligament A ligament is a type of fibrous connective tissue in the body that connects bones to other bones. It also connects flight feathers to bones, in dinosaurs and birds. All 30,000 species of amniotes (land animals with internal bones) have liga ...

in the

neck The neck is the part of the body in many vertebrates that connects the head to the torso. It supports the weight of the head and protects the nerves that transmit sensory and motor information between the brain and the rest of the body. Addition ...

. It connects the

cricoid cartilage The cricoid cartilage , or simply cricoid (from the Greek ''krikoeides'' meaning "ring-shaped") or cricoid ring, is the only complete ring of cartilage around the trachea. It forms the back part of the voice box and functions as an attachment sit ...

to the thyroid cartilage. It prevents these cartilages from moving too far apart. It is cut during an emergency

cricothyrotomy A cricothyrotomy (also called cricothyroidotomy or laryngotomy) is a medical procedure where an opening is created through the cricothyroid membrane to establish a patent airway during emergency airway management. Cricothyrotomy is primarily per ...

to treat upper

airway obstruction Airway obstruction is a blockage of respiration in the airway that hinders the free flow of air. Airway obstructions can occur either in the upper airway or lower airway. The upper airway consists of the nose, throat, and larynx. The lower ai ...

Structure

The cricothyroid ligament is composed of two parts: * the median cricothyroid ligament along the midline (a thickening of the cricothyroid membrane). It is a flat band of white

connective tissue Connective tissue is one of the four primary types of animal tissue, a group of cells that are similar in structure, along with epithelial tissue, muscle tissue, and nervous tissue. It develops mostly from the mesenchyme, derived from the mesod ...

that connects the front parts of the contiguous margins of the

cricoid The cricoid cartilage , or simply cricoid (from the Greek ''krikoeides'' meaning "ring-shaped") or cricoid ring, is the only complete ring of cartilage around the Vertebrate trachea, trachea. It forms the back part of the larynx, voice box and fun ...

and thyroid cartilages. It is a thick and strong ligament, narrow above and broad below. Each lateral ligament is known as the conus elasticus. * the lateral cricothyroid ligaments on each side (these are also called conus elasticus). Each is overlapped on either side by laryngeal muscles. The conus elasticus (which means elastic cone in Latin) is the lateral portion of the cricothyroid ligament. The lateral portions are thinner and lie close under the

mucous membrane A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It ...

of the larynx; they extend from the upper border of the cricoid cartilage to the lower margin of the vocal ligaments, with which they are continuous. The vocal ligaments may therefore be regarded as the free borders of each conus elasticus. They extend from the

vocal process In the human larynx, the vocal process is the anterior angle of the base of the arytenoid cartilage, as it projects horizontally forward and gives attachment to the vocal ligament. The arytenoids are paired cartilages with a medial and a lateral ...

es of the

arytenoid cartilage The arytenoid cartilages () are a pair of small three-sided pyramids which form part of the larynx. They are the site of attachment of the vocal cords. Each is pyramidal or ladle-shaped and has three surfaces, a base, and an apex. The arytenoid ...

s to the angle of the thyroid cartilage about midway between its upper and lower borders.

Relations

The prelaryngeal lymph node (also known as the Delphian lymph node) sits anterior to the median cricothyroid ligament.

Function

The cricothyroid ligament prevents the

and the thyroid cartilage from moving too far apart.

Clinical significance

The cricothyroid ligament is cut during an emergency

. This kind of surgical intervention is necessary during

above the level of

vocal folds In humans, the vocal cords, also known as vocal folds, are folds of throat tissues that are key in creating sounds through Speech, vocalization. The length of the vocal cords affects the pitch of voice, similar to a violin string. Open when brea ...

History

The cricothyroid ligament is named after the two structures it connects: the

and the thyroid cartilage. It is also known as the cricothyroid membrane, and the cricovocal membrane. The various parts of the cricothyroid ligament have been named in many different ways, which can cause confusion.

Other animals

The cricothyroid ligament can be found in many other animals, such as

cat The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the ...

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers. ...

s, and

horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 mi ...

s. The

trachea The trachea (: tracheae or tracheas), also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all animals' lungs. The trachea extends from ...

can be accessed through the cricothyroid ligament, such as for aspiration. It can be an important landmark.

Additional images

File:Slide5e.JPG, Cricothyroid ligament File:Slide3f.JPG, Cricothyroid ligament File:Slide6lll.JPG, Cricothyroid ligament File:Slide5ooo.JPG, Cricothyroid ligament File:Slide2deded.JPG, Muscles, nerves and arteries of neck. Deep dissection. Anterior view. File:Larynx detailed.jpg, Cricothyroid ligament

References

{{Portal bar, Anatomy Ligaments of the head and neck