The Sternothyroid muscle, also known as the sternothyroideus, is a small, flat muscle located in the neck region of the body. It is part of the infrahyoid muscles, a group of muscles located below the hyoid bone in the neck.
The Sternothyroid muscle is responsible for depressing the hyoid bone, which is a U-shaped bone located in the neck that helps to support the tongue and larynx. It is shorter and wider than the sternohyoid muscle, which is another infrahyoid muscle located in the neck region.
Structure
The Sternothyroid muscle is a narrow, flat muscle that runs from the sternum (breastbone) to the thyroid cartilage in the neck. It is one of the infrahyoid muscles, a group of muscles located below the hyoid bone in the neck. The Sternothyroid muscle is innervated by the ansa cervicalis, a nerve that arises from the cervical plexus and innervates several of the infrahyoid muscles.
There are several variations of the Sternothyroid muscle that can occur in some individuals. Some people may have an additional slip of the Sternothyroid muscle that originates from the manubrium (upper part of the sternum) or the xiphoid process (bottom part of the sternum). These additional slips may attach to the hyoid bone or the larynx (voice box).
Location
The Sternothyroid muscle is located in the neck region, just below the hyoid bone. It extends from the sternum to the thyroid cartilage, which is located at the front of the neck and forms part of the larynx. The thyroid cartilage is the largest of the cartilages that make up the larynx, and it is shaped like a shield or shield-like structure.
Function
The Sternothyroid muscle has several important functions in the human body. It plays a crucial role in breathing, as it helps to depress the larynx and trachea (windpipe) during inhalation. This helps to expand the thoracic cavity and allows more air to flow into the lungs.
The Sternothyroid muscle also plays a role in speaking and swallowing. It helps to tense the larynx and bring the thyroid cartilage forward, which is necessary for producing certain vocal sounds and swallowing food.
Clinical significance
The Sternothyroid muscle can be affected by various medical conditions, including muscle spasms, inflammation, and injuries. These conditions can cause pain and discomfort in the neck region and may affect the ability to breathe and speak properly.
In some cases, the Sternothyroid muscle may be damaged or impaired as a result of surgery or trauma. This can lead to problems with breathing and speaking, and may require treatment or rehabilitation to restore normal function.
