The rima glottidis is the opening between the two true

vocal cords In humans, vocal cords, also known as vocal folds or voice reeds, are folds of throat tissues that are key in creating sounds through vocalization. The size of vocal cords affects the pitch of voice. Open when breathing and vibrating for speech ...

anteriorly, and the two

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 posteriorly. It is part of the

larynx The larynx (), commonly called the voice box, is an organ in the top of the neck involved in breathing, producing sound and protecting the trachea against food aspiration. The opening of larynx into pharynx known as the laryngeal inlet is about ...

Anatomy

The rima glottidis is the narrowest part of larynx. It is longer (~23 mm) in males than in females (17-18 mm). The rima glottidis is an aperture between the two true

anteriorly, and the bases and

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 ...

of the two

s posteriorly. It is therefore described as subdivided into two parts: the larger anterior part between the

vocal folds In humans, vocal cords, also known as vocal folds or voice reeds, are folds of throat tissues that are key in creating sounds through vocalization. The size of vocal cords affects the pitch of voice. Open when breathing and vibrating for speech ...

(intermembranous part, or glottis vocalis), and the smaller posterior part between arytenoid cartilages (intercartilaginous part, glottis respiratoria, intercartilaginous glottis, respiratory glottis, or interarytenoid space). It is limited posteriorly by an interarytenoid fold of mucous membrane.

Function

The rima glottidis is closed by the

lateral cricoarytenoid Lateral is a geometric term of location which may refer to: Healthcare *Lateral (anatomy), an anatomical direction *Lateral cricoarytenoid muscle *Lateral release (surgery), a surgical procedure on the side of a kneecap Phonetics *Lateral cons ...

muscles and the

arytenoid muscle The arytenoid muscle is a single muscle of the larynx. It passes from one arytenoid cartilage to the opposite arytenoid cartilage. It has oblique and transverse fibres. It is supplied by the recurrent laryngeal nerve. It approximates the arytenoi ...

, and opened by the

posterior cricoarytenoid muscle The posterior cricoarytenoid muscles are small, paired intrinsic muscles of the larynx that extend between cricoid cartilage to the arytenoid cartilages in the larynx. Structure Origin and insertion The posterior cricoarytenoid originates f ...

s. All of these muscles receive innervation from the

recurrent laryngeal nerve The recurrent laryngeal nerve (RLN) is a branch of the vagus nerve (cranial nerve X) that supplies all the intrinsic muscles of the larynx, with the exception of the cricothyroid muscles. There are two recurrent laryngeal nerves, right and le ...

which is a branch of the

vagus nerve The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and right ...

(CN X). The shape of rima glottidis is changed by movements of vocal cords and arytenoid cartilages during respiration and phonation.

Clinical significance

Any damage to the rima glottidis may result in a hoarse voice,

aphonia Aphonia is defined as the inability to produce voiced sound. Damage to the nerve may be the result of surgery (e.g., thyroidectomy) or a tumor. Aphonia means "no sound". In other words, a person with this disorder has lost their voice. Causes ...

or difficulty breathing.

References

External links

* Human head and neck {{Anatomy-stub