Its primary function is to cover and protect the end of the bones in the joints.
Like any other cartilage in the human body, Thyroid cartilage is generally smooth but firm tissue. The hardness and elasticity of cartilage are between that of a bone and a muscle.
The thyroid cartilage is the largest among the laryngeal cartilages. It is created from the left and right lamina, largely isolated posteriorly; however, they converge and unite earlier.
The uppermost point of the site of combination between the two broad lamina planes projects forward the laryngeal prominence, that is, Adam’s apple.
The angle in the middle of the two blades is more acute in men, that is, 90 °, compared to women, that is, 120 °; As a result, Adam’s apple is more protruding in men than in women.
Cartilage is made of specialized cells known as chondrocytes. These cells form a collagenous extracellular matrix. This has proteoglycan and elastin fibers in abundance.
Cartilage does not contain nerves or blood vessels. Its nutrition takes place due to diffusion. Cartilage tissue cannot repair itself.
The thyroid cartilage is not always symmetrical. If a significant asymmetry does not produce any symptoms, it should be left without medical intervention.
Types of cartilage
Cartilage can be of three types:
- Hyaline cartilage
This is the most common type. It is found in the ribs, nose, larynx, and windpipe. It is a bone precursor. When cool, it has a glassy appearance. It is composed of fine collagen fibers that are widely dispersed and provide strength. It has a perichondrium. This type of cartilage is the weakest of the three.
This type of cartilage has alternating films of hyaline cartilage matrix and thick collagen fibers. This characteristic makes it the most vital kind of cartilage among the three. It does not have a perichondrium.
It is usually a transitional surface between a ligament and the hyaline cartilage. Cartilage contains intervertebral discs, joint capsules, and ligaments.
- Elastic cartilage
This type of cartilage is found in the outer ear, epiglottis, and larynx. It gives elasticity, resistance, and maintenance to the shape of particular structures. It has a perichondrium, and its chondrocytes form a filamentous network of elastic fibers within the matrix.
Thyroid cartilage anatomy
The thyroid cartilage is located between the C4 and C5 vertebrae. Cartilage consists of two plates, known as laminae. They are quadrilateral in shape and extend to cover each side of the windpipe.
They form the lateral portions of the thyroid cartilage. The left lamina and the right lamina are posteriorly separated. They are fused in the front of the neck at 90 to 120 degrees.
Each plate has a sloping ridge with a small rounded projection (tuber) up and down.
The left lamina and the right lamina are posteriorly separated. The posterior edges project as upper and lower horns. The prominent horn joins the hyoid bone upward by the thyrohyoid membrane.
It is narrow and long, ending in a cone-shaped structure that connects to the thyrohyoid ligament. The upper horn is also known as “cornu.”
The lower horn connects with the cricoid cartilage downward with the help of the cricothyroid membrane in the midline and the cricothyroid muscles on the sides. It is thick and short and has a less forward lean.
The upper thyroid notch is V-shaped and immediately at the melting point. The lower crack is less noticeable and is located along the cartilage base in the midline.
As they diverge laterally, the superior thyroid notch separates the two laminae above the laryngeal prominence. The prominent thyroid notch and laryngeal prominence are important anatomical markers in the neck.
In the midline, adjacent to the base of the thyroid cartilage, there is a less conspicuous inferior thyroid notch.
To create an upper horn and a lower horn, the posterior border of each lamina of the thyroid cartilage is stretched outward.
There is a facet for articulation with the cricoid cartilage on the medial surface of the lower horn.
A lateral thyrohyoid ligament joins the prominent horn and the posterior end of the more excellent funnel of the hyoid.
The oblique line marked the lateral surface of each thyroid lamina, which curves forward from the base of the upper horn to just beyond the middle of the lower edge of the lamina.
The ends of the oblique line are extended to create upper and lower thyroid tubercles. The extrinsic muscles of the larynx, sternothyroid, thyrohyoid, and inferior constrictor join in the diagonal line.
The angle created by the laminae of the thyroid cartilage results in a lump that is larger and more prominent in men, Adam’s apple. It is considered a secondary sexual characteristic in men. It develops in size during adolescence in both men and women.
The difference in cartilage size between men and women is due to the angle formed by the two parts of the cartilage. In men, the tip is approximately 90 degrees, while in women, it is 120 degrees. This gives men a sharper neck structure.
Thyroid cartilage relationships
The thyroid cartilage is located superiorly to the cricoid cartilage; it is another hyaline cartilage.
The posterior portion of the cricoid is highly stretched, which provides support by not involving the thyroid cartilage.
The cricoid and thyroid cartilages protect the glottis and the entrance to the trachea, and the essential laryngeal muscles and ligaments are attached to the surfaces provided by them.
The upper surface of the cricoid cartilage connects with the arytenoid cartilages.
The thyroid cartilage connects with the cricoid through the ligaments and two joints with the synovium.
The shoehorn epiglottis creates a covering over the glottis and protrudes into the glottis. The epiglottis has ligamentous connections to the anterior and superior margins of the thyroid cartilage and the hyoid bone. It is made up of elastic cartilage.
The vestibular and vocal ligaments are surrounded by folds of the laryngeal epithelium that protrude into the glottis. The vestibular ligaments, along with the vocal ligaments, run between the thyroid cartilage and the arytenoid cartilages.
The vestibular ligaments are found within the vestibular folds’ upper pair of folds. These folds protect the more fragile vocal cords and help prevent foreign objects from entering the glottis.
The vocal cords are inferior to the vestibular folds and protect the entrance to the glottis.
The vestibular ligaments and the vocal ligaments are found in the middle of the thyroid cartilage and the arytenoid cartilages.
Since the vocal ligaments are made of elastic tissue, the vocal cords are very flexible. The vocal cords are involved in creating sound, which is why they are also known as the vocal cords.
Another important external landmark of the thyroid cartilage is the oblique line. It runs anteroinferior from an upper thyroid tubercle below the superior cornu and extends into the lower thyroid tubercle at the lower margin of the thyroid lamina.
The oblique line is a ridge that is attached to it:
- Watch a video.
- External thyroid.
- Lower pharyngeal constrictor muscles.
The fibers of the palatopharyngeal and stylopharyngeal muscles and the posterior border of the thyroid cartilage are attached.
As its name suggests, the thyroid cartilage has nothing to do with the thyroid gland or its processes.
- The thyroid cartilage contains the vocal cords, also known as vocal folds. It gives them protection and support.
- The vocal cords are folds of membranous tissue that project inward from the sides of the larynx to form a slit in the throat. The vibration of its edges with the help of a stream of air produces vocalization.
- When the thyroid cartilage moves, it changes the stress levels creating variations in the human voice. These variations are also influenced by the angle at which the thyroid cartilage forms with the cricoid cartilage.
- The laminae of the thyroid cartilage move together with the cricoid cartilage at their place of attachment, which is the cricothyroid joint.
- Many muscles find their attachment point in the thyroid cartilage.
Thyroid cartilage pain
Thyroid pain is any discomfort or pain emanating from the thyroid gland due to disease processes within the gland or rarely due to neighboring structures in the neck and upper chest that affect the thyroid gland.
Damaged cartilage can cause pain, stiffness, inflammation, or swelling. But the pain in cartilage does not always mean that the cartilage has been damaged.
You may experience thyroid cartilage pain due to various reasons. These include a sore throat, increased tension in the surrounding muscles, or a cartilage fracture.
Thyroid gland pain is often not identified if other signs of thyroid dysfunction symptoms are not evident.
Sometimes the source of pain is in areas around the cartilage and not in the cartilage itself.
Pathology in any surrounding neck structures, such as the neck muscles, larynx, trachea, esophagus, cervical lymph nodes, and even blood vessels, will cause pain.
This condition involves irritation, pain, itching, and inflammation of the throat. You may find it difficult to swallow food and liquids. The most common causes of a sore throat are common colds and viral or bacterial infections.
A sore throat can be treated at home with warm salt water and anti-inflammatories, but it is advisable to visit a doctor when the pain lasts more than a week.
Tension in the throat muscles
Throat tension and vocal fatigue are frequent complaints. They occur when you use your voice excessively or incorrectly. But they can also take place due to dehydration.
The tension in the throat leads to an abnormal sound, which could be described as tinny, tight, and choppy. It also causes pain and voice problems. This stress can be relieved with relaxation exercises.
Thyroid cartilage fractures can be of three types:
- Nondisplaced fractures with minor laryngeal injuries.
- Moderately displaced fractures with severe injuries and laryngeal defects.
- Major fractures with severe damage to the larynx.
After a complete diagnosis and determination of the severity of the damage, the doctor will decide on a treatment that includes conservative, non-surgical, or surgical therapies.
There may be other lesser-known causes of pain in the thyroid cartilage region. Symptoms can be associated with different types of health problems. It is better to visit the doctor and let them review and decide on the most appropriate treatment.
The hysterical balloon is the persistent sensation of having phlegm, a pill, or another type of obstruction in the throat when there is none. It is also known as a balloon sensation, globus, or somewhat old-fashioned Globus hystericus, commonly described as having a “lump in the throat.”
Swallowing can usually be done, so it is not an actual dysphagia condition. However, it cannot be enjoyable. Moderate chest pain or even severe pain may also be felt when swallowing along with a popping sound.
A little-known inflammatory condition of the lateral thyrohyoid ligament and nearby tissues in the neck.
The diagnosis is confirmed by finger or thumb pressure to find a point of acute tenderness over the more excellent horn of the hyoid bone and sometimes over the upper border of the thyroid cartilage.
The clinician may also find it helpful, for comparison, to apply gentle pressure on the submandibular gland or carotid artery to confirm that the point of tenderness is indeed most significant on the thyroid ligament, hyoid, or lateral thyroid cartilage.
Treatment of thyrohyoid syndrome is usually supportive and may include reducing percussive or aggressive use of the voice and non-steroidal anti-inflammatory drugs.
Or instead (for much more effective) injection of 0.5 ml of Kenalog 40 mg per ml in the lateral point of the hyoid and the superior border of the thyroid cartilage, which require care and experience since it is just anterior to the carotid artery.
Other symptoms of thyroid cartilage pain
Thyroid cartilage pain can range in intensity from discomfort described as tightness, especially when swallowing, to a dull ache throughout the gland that is exacerbated when palpated (tenderness).
Acute pain in the thyroid cartilage is rare in cases other than viral thyroiditis, but persistent pain may be prominent enough to indicate medical or surgical intervention.
Thyroid cartilage pain can be accompanied by other clinical features such as:
- Enlarged thyroid gland (goiter) that appears as an anterior neck mass.
- Discomfort (dysphagia) or pain (odynophagia) when swallowing.
Signs and symptoms of thyrotoxicosis (hyperthyroidism): diarrhea, tremors, irritability, insomnia, weight loss, sensitivity to heat, sweating.
Signs and symptoms of hypothyroidism: constipation, depression, weight gain, menstrual irregularity (women), fatigue, intolerance to cold, dry hair, and brittle nails.
Causes of pain
The larynx can be injured due to various causes. A damaged larynx can cause hoarseness, voice loss or alteration, pain in the throat or ears, and difficulty breathing.
Some of the more common causes of pain and damage to the larynx include:
Laryngitis – is the most common inflammatory disease of the larynx. It occurs due to infections. Its symptoms are sore throat, hoarseness, and shortness of breath.
Fractures – lead to coughing up blood, sore throat, and shortness of breath. It can cause displacement and edema of the larynx and suffocation.
Acid or alkali poisoning (vinegar, washing liquids, ammonia, caustic soda): its signs are a burning sensation on the lips, sore throat, vomiting of blood, and profuse salivation.
Fibroids and Papilloma: These are benign tumors that cause hoarseness and pain in the throat.
Laryngeal cancer: can cause dryness, shortness of breath, sore throat spreading to the ear, and a sensation of a foreign substance in the throat.
As the tumor spreads, the tone of the voice gradually changes, and other symptoms begin to appear, such as weight loss and general weakness.
Falling of foreign bodies into the larynx from the oral cavity: This is observed in children who have a habit of keeping small objects in their mouths. If the foreign body cannot be expelled by coughing, it slides into the windpipe and reaches the bronchi. It can develop asthma in the patient.
Observed symptoms are whooping cough, sore throat, blue face and lips, and hoarseness. If there is a complete blockage of the airway, the resulting suffocation can lead to death.
Gastroesophageal reflux: causes burns in the heart, sore throat, belching, and pressure in the abdomen and above it.
Thyroid cartilage reduction
Thyroid cartilage reduction, chondrolaryngoplasty, or ” tracheostomy scraping ” is an operation to reduce the size of Adam’s apple on the neck in transsexual women.
It is done through a small incision within an existing crease in the neck. This procedure is done under general anesthesia as an outpatient surgery. This procedure can be combined with other facial feminization surgery or gender-affirming surgery.
Who is a good candidate for thyroid cartilage reduction surgery?
Transgender or gender-expansive patients with a prominent Adam’s apple are candidates for chondrolaroplasty. No specific preparation letters are required for tracheal shaving surgery, as in the case of gender-affirming surgery on the chest or genitals.
What should I do in the lead-up to my thyroid cartilage reduction surgery?
Your doctor will give you instructions before surgery, including guidelines on eating, drinking, or avoiding certain medications and vitamins. Avoid smoking or tobacco use for four to six weeks before surgery and aspirin for 14 days before and after the procedure.