The Neck Flashcards
What is the neck
The junction between the head and thorax
What is the superior limit of the neck
The mandible and the base of the skull
What is the inferior limit of the neck
The thoracic inlet
What is the neck divided into anterior and posterior portions by
Sternocleidomastoid
What is the proximal attachment of the neck
Mastoid process
What is the distal attachment of the neck
Sternum and clavicle
What are the two triangles of the neck
Anterior triangle and posterior triangle
What are the boundaries of the anterior triangle of the neck
1) sternocleidomastoid muscle
2) the midline
3) the lower border of the mandible
What are the boundaries of the posterior triangle rod the neck
1) sternocleidomastoid
2) trapezius muscle
3) middle third of the clavicle
What can the contents do the anterior triangle be divided into
1) muscles
2) skeletal elements and viscera
3) glands
4) nerves
5) vessels
What muscles are in the anterior triangle
- mylohyoid
- anterior belly of digastric
- infrahyoid (strap) muscles (sternohyoid, sternothyroid, thyrohyoid, omohyoid)
What are the skeletal elements of the anterior triangle
- thyroid cartilage - largest of the laryngeal cartilages
- cricoid cartilage - below the thyroid cartilage, just above the trachea
- hyoid bone
- trachea
What is the function of the infrahyoid muscles
Muscles underneath the mylohyoid muscle, stabilises the hyoid bone
What are the glands in the anterior triangle
- thyroid gland
- parathyroid glands
- submandibular glands
What are the parathyroid hormones responsible for
Calcium release in the body
What are the thyroid hormones responsible for
Metabolism and nerve development
How to test the thyroid gland
Hands on the neck and get the patient to swallow
What is the thyroid gland supplied by
Supplied by the superior (external carotid artery) and inferior thyroid (thyrocervical trunk) arteries
What ways do the parathyroid gland increase blood calcium levels
1) increasing absorption from the gut
2) increasing absorption from the kidney
3) increased activity of oesteoclasts - break down bone and release calcium
Describe the structure of the parathyroid gland
Superior 2x - found roughly in the middle of the posterior border of the thyroid lobes
Inferior 2x - at inferior poles of thyroid gland, although can be a little variable
5% of people have more than 4
What nerves are in the anterior triangle in the neck
- vagus
- phrenic
- hypoglassal
What is the function of the phrenic nerve
C3-5
- supplies the diaphragm
- used to be surgically divided as a treatment for TB
What is the function of the hypoglossal nerve
Innervates the majority of the muscles and the tongue
What vessels are found in the anterior triangle of the neck
- common carotid artery
- jugular veins
What vein mainly drains the head and neck
Jugular vein
What are the contents of the posterior triangles
1) nerves
2) muscles
3) vessels
4) lymph nodes
What nerves are in the posterior triangle
- accessory nerve
- parts of the brachial plexus
- cutaneous cervical nerves
Sternocleidomastoid muscle
Sternocleidomastoid muscle – lateral flexion of neck when acting on its own and flexion of neck when acting both left and right sides.
Trapezius
Trapezius – base of skull and C7-T12 vertebrae spinous processes to lateral third of clavicle and scapula (acromion of)
Describe the posterior triangle nerves
It is divided into three parts – upper, middle and lower fibres. The upper fibres elevate the scapula, and also rotate during abduction of the arm. Middle fibres pull back the scapula (retraction) and lower fibres go inferiorly
Describe the lymph nodes in the posterior triangle
- small oval to bean shaped structures
- they filter lymph
- offer defence against the spread of infection
- returned to larger veins
- many sites of lymph nodes
What is the most important function of lymph nodes
Fight against infection
