The Neck Flashcards
Provide an overview of the structure of the neck
The neck is located between the head and the shoulders. It consists of various structures, including the cervical vertebrae (bones of the neck), muscles, blood vessels, nerves, and glands. The neck provides support for the head and allows for movement in different directions.
Describe the functions of the blood supply of the neck
The neck has a complex network of blood vessels that ensure proper circulation. The main arteries in the neck are the common carotid arteries, which branch off into the internal and external carotid arteries. These arteries supply blood to the brain, face, and neck.
The internal carotid artery primarily provides blood to the brain, while the external carotid artery supplies blood to the face, scalp, and neck muscles.
The external carotid artery has various branches, including the facial artery, which supplies blood to the face, and the occipital artery, which supplies blood to the back of the head.
Veins in the neck, such as the internal jugular vein and external jugular vein, help drain blood from the head and neck back to the heart. These veins play a crucial role in returning deoxygenated blood to the heart for oxygenation.
The lymphatic system in the neck also plays a vital role in maintaining fluid balance and immune function. Lymph nodes in the neck filter lymph fluid, removing waste products and harmful substances.
Describe the anatomy and functions of the nerve supply of the neck
The neck is innervated by several nerves. The main ones are the cervical spinal nerves, which branch off from the spinal cord and supply sensation and motor function to different areas of the neck. The nerves of the neck also contribute to controlling the muscles, glands, and blood vessels in the region.
Describe the musculature of the neck
- Musculature of the Neck:
The neck contains numerous muscles that perform various functions. Some important muscles include the sternocleidomastoid, which helps with head rotation and flexion, and the trapezius, which supports shoulder movement and helps maintain posture. Other muscles in the neck are involved in swallowing, breathing, and speaking.
Describe the anatomy and function of the thyroid
The thyroid gland is a butterfly-shaped gland located in the front of the neck, just below the Adam’s apple. It consists of two lobes connected by a narrow strip of tissue called the isthmus. The thyroid is made up of many tiny follicles that contain cells called thyroid follicular cells.
The thyroid gland plays a crucial role in regulating various bodily functions through the production of thyroid hormones. The main hormones produced by the thyroid are thyroxine (T4) and triiodothyronine (T3). These hormones are involved in controlling metabolism, growth, and development.
The thyroid gland is regulated by the hypothalamus and pituitary gland. When the levels of thyroid hormones in the blood are low, the hypothalamus releases thyrotropin-releasing hormone (TRH), which signals the pituitary gland to release thyroid-stimulating hormone (TSH). TSH then stimulates the thyroid gland to produce and release more thyroid hormones.
Thyroid hormones have a widespread effect on the body. They help regulate heart rate, body temperature, digestion, and the breakdown of nutrients. They also play a crucial role in brain development, bone growth, and maintaining healthy skin and hair.
Sometimes, the thyroid gland can develop certain conditions, such as hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid), which can affect hormone production and lead to various symptoms.
Describe the anatomy and function of the parathyroid
The parathyroid glands are small, pea-sized glands located near the thyroid gland in the neck. There are usually four parathyroid glands. Their main function is to regulate calcium levels in the body. They produce parathyroid hormone (PTH), which helps control calcium absorption from the intestines, release calcium from bones, and regulate calcium reabsorption in the kidneys.
Name and describe the two triangles in the neck
anterior: communicates with head and thorax
Anterior border of steliocleidomastoid muscle
Anterior sound surface in midline
Inferior border of mandible
posterior: communicates with upper limb
Posterior aspect of steiloclediomastoid muscle
Middle 1/3 of clavicle
Anterior border of trapezius musc
State and describe the three types of venous drainage in the neck
Internal Jugular Vein:
• Location: Runs alongside the internal carotid artery within the carotid sheath.
Drains: Receives blood from the brain, face, and neck.
• Connection: Joins with the subclavian vein to form the brachiocephalic vein.
- External Jugular Vein:
• Location: Located superficially on the side of the neck.
• Drains: Collects blood from the scalp and parts of the face and neck.
• Connection: Empties into the subclavian vein. - Vertebral Vein:
Location: Drains the cervical vertebrae and spinal cord.
• Course: Runs within the vertebral canal.
• Connection: Typically drains into the brachiocephalic vein
Describe the arterial blood supply to the head and neck
The head and neck receive their blood supply from major arteries, including the common carotid artery, which branches into the internal carotid artery (for the brain) and the external carotid artery (for the neck and face). The external carotid artery further branches into arteries like the facial artery, maxillary artery, and superficial temporal artery. Additionally, the vertebral artery supplies blood to the back part of the brain. These arteries work together to provide oxygen and nutrients to the head and neck tissues and organs.
Describe the location of the thyroid gland in the neck
2 bilateral lobes covering antero-lateral part of trachea
Weighs 25g and 5cm long
Develops as part of pharynx and migrates into inferior position through thyroglossal duct
Highly vascular structure
Arterial supply through superior thyroid and inferior thyroid arteries
venous return through thyroid veins into internal jugular
Innervated by recurrent laryngeal nerves
Name the 2 iodine based hormones produced by the thyroid gland
Tripdothyronine
Thyroxine
