The Neck Flashcards
Borders of the neck
Anteriorly - from the lower border of the mandible to the upper surface of the manubrium
Posteriorly - from the superior nuchal line (occipital bone) to the intervertebral disc between C7 and T1
Functional compartments
Anterior visceral compartment - parts of digestive and respiratory systems and endocrine glands
Posterior vertebral compartment - cervical vertebrae, spinal cord, cervical nerve, muscles (support)
2 lateral neurovascular compartments - blood vessels and vagus nerve
Fascia of neck
Superficial and deep
Superficial fascia contains
thin sheet of muscle than blends in with the muscles of the face
Deep fascia contains
Investing layer - surrounds everything
Pre vertebral layer - surrounds posterior compartment
Pre tracheal layer - surrounds anterior compartment
Carotid sheaths - surround neurovascular compartments
Neck - C1
Open mouth
Neck - C2
Superior cervical ganglion
Neck - C3
Body of hyoid
Neck - C4
Upper body of the thyroid cartilage, bifurcation of common carotid artery
Neck - C6
Cricoid cartilage, middle cervical ganglion
Neck - C7
Inferior cervical ganglion
Boundaries of thoracic inlet
T1 posteriorly, 1st ribs anteriorly, superior border of the manubrium anteriorly
Structures passing through the thoracic inlet
trachea oesophagus brachiocephalic veins and arteries vagus nerves left common carotid and subclavian arteries sympathetic trunk left recurrent laryngeal nerve phrenic nerves
Boundaries of the anterior triangle of the neck
Anterior border of sternocleidomastoid
Inferior border of the mandible
Midline of neck
Boundaries of the posterior triangle of the neck
Posterior border of sternocleidomastoid
Anterior border of the trapezius
Middle 1/3 of clavicle
Contents of the anterior triangle of neck
Mainly Muscles:
- Mylohyloid
- Platysma (superficial facial muscle)
- Digastric
- Infrahyoid (strap)
Common carotid arteries
Internal jugular vein
Larynx and trachea
Contents of the posterior triangle of neck
Mainly blood vessels and nerves:
- External jugular vein
- Internal jugular bein
- Subclavian artery and vein
- Trunks of the brachial plexus
- Phrenic nerve
- Spinal accessory nerve
- Vagus nerve
Mylohyoid muscle attachments and function
From the myohyloid line on the mandible - inserts in the body of the hyoid
Function - support and elevate floor of mouth
The infrahyoid (strap) muscles
Sternohyoid
Omohyoid
Thyrohyoid
Sternothyroid
Sternohyoid attachments
From the posterior aspect of the sternoclavicular joint to the body of the hyoid
Omohyoid attachments
From the superior border of the scapular to the lower border of the hyoid
Thyrohyoid attachments
From the thyroid cartilage to the greater horn of the hyoid
Sternothyroid attachments
From the posterior surface of the manubrium to the thyroid cartilage
Brachial plexus relation to the thoracic inlet
Superolateral to the thoracic inlet
Brachial plexus emerges between which muscles
Anterior and middle scalene muscles, passes under the clavicle and into the shoulder
5 roots of the brachial plexus
Anterior rami of the spinal nerves C5-T1
The 3 trunks the roots merge to form and where they cross
1) Upper trunk C5-6
2) Middle trunk C7
3) Lower trunk C8-T1
cross in the posterior triangle of the neck
Superficial venous drainage of the neck:
external jugular vein and anterior jugular veins
Position and key relations of the external jugular vein
Formed posterior to the angle of the mandible
Passes straight down the neck in the superficial fascia
Superficial to the sternocleidomastoid muscle
crosses down diagonally
Pierces investing layer of deep cervical fascia
Joins the subclavian vein
Position and key relations of the anterior jugular vein
Paired veins that come together superior to the hyoid bone
Descend on either side of the midline
Near the medial side of the sternocleidomastoid, each vein pierces the investing layer of the deep cervical fascia
Joins the subclavian vein
Subclavian vein joins the…to form…near the
Internal jugular vein to form the brachiocephalic vein near the sternoclavicular joint
Explain the uses of central venous lines
Need to place larger-bore catheter into the central vein - dialysis, parenteral nutrition, haemodynamic monitoring or administration of drugs than tend to cause phlebitis
Indicate landmarks for insertion of a central line into the internal jugular vein
Previously: blind puncture into subclavian and jugular veins
Now: ultrasound to ID vessels
IJV puncture site: palpate common carotid artery and insert the needle just lateral to it (30 degree angle aiming at the apex of the sternal and clavicular heads of the sternocleidomastoid)
Direct needle inferolaterally towards ipsilateral nipple
List the possible complications of insertion of central venous lines
Arterial puncture leading to haematoma and potential airway obstruction Pneumothorax Nerve damage Air embolism Thrombosis Misplacement Perforation of great vessels of heart Infection
Brachiocephalic trunk branches into
subclavian and common carotid arteries
Subclavian artery branches
1st branch - vertebral artery
2nd branch - Thyrocervical trunk
3rd branch - internal thoracic artery
Position, key relations and course of vertebral artery
Medial to the anterior scalene
Ascends through the transverse process of C6.
At the superior border of C1, it turns medially
Passes through the foramen magnum into the posterior cranial fossa.
Position, key relations and course of internal thoracic artery
Branches from inferior end of subclavian and descends
Passes posterior to clavicle and large veins of the region and anterior to the pleural cavity
Enters thoracic cavity posterior to the ribs and anterior to the transversus thoracis muscle
Left and right common carotid arteries originate from
Right: brachiocephalic trunk
Left: Aortic arch, entering the neck near the left sternoclavicular joint
Where the common carotids bifurcate
Superior edge of thyroid. Divide into internal and external carotids.
Where and what is the carotid sinus
At the bifurcation of the common carotids. It is a dilation of the internal carotid
Internal carotid enters the cranial cavity via
carotid canal
Internal carotid supplies
cerebral hemispheres, eyes, contents of orbit, forehead
External carotid supplies
Face, neck and scalp
Where to locate the carotid pulse
Palpate common carotids - lie in groove between trachea and infra hyoid muscles
Uses of carotid pulse
Assess pulse pace, rhythm, character
Timing murmurs
Locate jugular vein
Lymphatic drainage pattern
Superficial lymph vessels–> superficial lymph nodes –> deep nodes –> deep nodes of the jugular vein
5 groups of superficial nodes round the head neck and scalp
Occipital (most posterior to ears) Mastoid (less posterior to ears) Parotid (anterior to ears) Submandibular (on jawline) Submental (just to side of chin)
Drainage from the occipital and mastoid nodes pass to the
Superficial cervical nodes
Superficial cervical nodes form along the…
Deep cervical nodes form along the…
(superficial) external jugular vein
(deep) internal jugular vein
from the deep cervical nodes, lymphatic vessels form… which empty into the…
Form the right and left jugular trunks
Empty into the Right lymphatic duct on the right side
or the thoracic duct on the left side
Phrenic nerves are branches of the
cervical plexus and arise from the anterior rami of C3-C5
Route of phrenic nerves
Pass the upper lateral border of the anterior scalene muscle
Interiorly down the anterior surface of the anterior scalene muscle with the pre vertebral fascia
past the lower edge of the anterior scalene
Pass between subclavian vein, enter thorax and continue into the diaphragm
Right phrenic passes close to the IVC
Left phrenic pierces the diaphragm
Function of phrenic nerves
Motor supply to diaphragm
Sensory innervation of diaphragm pleura and peritoneum
Spinal accessory nerves considered to be
CN11
Spinal accessory nerves origin
Neutron cell bodies of cervical spinal cord
Spinal accessory nerves course
Enters the skull via foramen magnum
Courses along inner wall of skull to jugular foramen where it exits the skull
In the neck, they cross the internal jugular vein (at level of posterior belly of digastric), continues inferiorly, pierces the SCM, reaches trapezius
Spinal accessory nerves function
motor innervation ro SCM (head rotation) and trapezius (shrugging)
