Clinical Anatomy of Neck and Clinical Correlations

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Transcript Clinical Anatomy of Neck and Clinical Correlations

Clinical Anatomy of Neck
Clinical Correlations
USMLE I’s high yield
Associate Professor
Dr. A. Podcheko
2015
Fascia of the neck
• Divided into superficial & deep layers
• Deep layer of cervical fascia further divided into: superficial,
middle, & deep portions:
Superficial:
-envelops SCM & trapezius muscles
-Extends superiorly to hyoid bone where it surrounds the
submandibular gland & the mandible
-Inferiorly, attaches to clavicle
-Medially it forms floor of submandibular space as it covers the
muscles of the floor of mouth.
Fascia of the neck
Middle (aka visceral or pretracheal fascia): surrounds
infrahyoid strap muscles, thyroid, larynx, trachea, &
esophagus. Below hyoid, this layer continues
inferiorly to fuse with pericardium. Above hyoid, this
layer continues on the posterior pharyngeal wall as
the buccopharyngeal fascia.
Fascia of the neck
• Deep (aka prevertebral fascia):
-surrounds prevertebral muscle.
-Anteriorly, it divides to form a thin alar layer & a
thicker prevertebral layer. Between these two layers
is the "danger space," extending from the skull base
to diaphragm.
Alar fascia
prevertebral
fascia
Anatomy of neck spaces
• These spaces are important from the point
of view of clinician because of the
propensity of infections to involve this
space and to spread along these spaces
to involve other areas like the mediastinum
Upper neck spaces
• Submandibular space: Space below
mylohyoid muscle and above platisma
• Sublingual space: Space above the
mylohyoid muscle and below base of the
tongue
• Submental space: Space between anterior
bellies of digastric muscles
Lateral pharyngeal space (Para
pharyngeal space)
• This space is situated lateral to the fascia
covering the constrictor muscles of the pharynx
(buccopharyngeal fascia). Lateral to this space
lie the pterygoid muscle, mandible and carotid
sheath.
• Superiorly it extends up to the skull base while
inferiorly it ends at the level of hyoid bone
• Posteriorly this space communicates with the
retropharyngeal space.
Axial section
through the
ramus of the
mandible
showing
relationships
of the
parapharynge
al space
Retropharyngeal space/Danger
Space
• Boundaries
anteriorly - alar fascia
posteriorly - prevertebral fascia
superiorly - extends from the clivus
inferiorly - posterior mediastinum at the level of
the diaphragm
• It is a potential path for spread of infections from the
pharynx to the mediastinum.
• In healthy patients, it is indistinguishable from
the retropharyngeal space
• It is only visible when distended by fluid or pus,
below the level of T1-T6, since the retropharyngeal
space variably ends at this level.
• A 36-year-old woman presents to your office with
complaints of worsening throat pain for the past six days.
She also has pain in her ears and neck as well as difficulty
swallowing. On examination she has excessive salivation
and difficulty opening her mouth. Her temperature is
39°C (102 2°F), blood pressure is 130/80 mmHg, pulse is
100/min, and respiratory rate is 18/min. Which of the
following neck space infections carries the highest risk of
mediastinal involvement?
•
•
•
•
A Submandibular space
B Sublingual space
C. Parapharyngeal space
D. Retropharyngeal space
Ludwig angina (LA)
• Ludwig’s angina is an infection of the floor of the mouth
(submandibular space) with secondary involvement of the
sublingual and submental spaces, usually resulting from a
dental infection (Staphylococcus,Streptococcus,
and Bacteroides species)
• Hairline fractures (after extraction of a tooth) may occur in the
lingual cortex of the mandible, providing microorganisms
ready access to the submandibular space. By following
the fascial planes, the infection may dissect into the
parapharyngeal space and, from there, into the carotid
sheath.
• Symptoms include painful swelling of the floor of the mouth,
elevation of the tongue, dysphagia (difficulty in swallowing),
dysphonia (impairment of voice production), edema of the
glottis, fever, and rapid breathing.
The Carotid Sheath
The carotid sheath is a tubular
This sheath blends anteriorly with & invests
fascial investment that extends from pretracheal layers of fascia & posteriorly with
the cranial base to the root of the
the prevertebral layer of fascia.
neck.
Contents of The Carotid Sheath
The carotid sheath contains
(1)the common & internal carotid arteries
(2)the internal jugular vein
(3)vagus nerve (CN X)
(4)some deep cervical lymph nodes,
(5)carotid sinus nerve
(6)sympathetic nerve fibers (carotid periarterial
plexuses)
The Carotid Sheath
The carotid sheath and pretracheal fascia communicate freely with the
mediastinum of the thorax inferiorly and the cranial cavity superiorly.
These communications represent potential pathways for the spread of infection
and extravasated blood.
• A 40-year-old woman is hospitalized because of a
massive neck infection that developed over a period of
3 days after extraction of an impacted wisdom tooth.
She has a high fever, and her lower jaw and entire
neck are swollen, red, and painful. Throat culture
reveals a mixed bacterial flora, containing both aerobic
and anaerobic microorganisms. Which of the
following is the most likely diagnosis?
• (A) Actinomycosis
• (B) Acute necrotizing ulcerative gingivitis
• (C) Ludwig angina
• (D) Pyogenic granuloma
• (E) Scarlet fever
Lemierre's Syndrome
- aka abscess of lateral pharyngeal/
retropharyngeal space
• The "angina" in this syndrome refers to an
acute pharyngeal infection with the
anaerobe Fusobacterium necrophorum.
• The acute pharyngitis is followed by a septic
thrombophlebitis of the internal jugular vein
and dissemination of the infection to multiple
sites distant from the pharynx.
• In the preantibiotic era, Lemierre's syndrome
was often fatal
Lemierre's Syndrome
• MC in Adolescents, Adults
• The first sign of Lemierre's syndrome is usually
a persistent fever, followed by acute pharyngitis
and then sepsis.
• Neck tenderness or swelling develops
• Contrast computed tomography of the neck
provides the definitive diagnosis, showing
distended veins with enhancing walls,
intraluminal filling defects, and swelling of
adjacent soft tissues.
Lemierre's Syndrome Morphology
• Abscesses caused by anaerobes contain discolored and foul-smelling
pus that is often poorly walled off
• Complications: carotid erosion; airway obstruction; lung, contiguous spread
to mediastinum; septicemia
•A 23-year-old Caucasian male presents to the
emergency department complaining of neck pain for the
past two days. He states that a chicken bone scratched
the back of his throat a week ago. Two weeks ago he
was in Arizona visiting his friends. He is otherwise
healthy and has never been hospitalized. His
temperature is 39° C (102.2° F), blood pressure is
125/85 mmHg and heart rate is 120/min. On
examination, he refuses to fully open his mouth. Neck
movements especially neck extension, are restricted
secondary to pain. Which of the following is the most
likely diagnosis'?
A Meningitis
B Herpangina
C Epiglottitis
D. Diphtheria
E. Infectious mononucleosis
F. Retropharyngeal abscess
What is shown on these
pictures?
Torticoils (Wry neck)
• Spasmodic contraction or shortening of the neck
muscles, producing twisting of the neck with the chin
pointing upward and to the opposite side.
• Torticollis is a contraction of the cervical muscles
that produces twisting of the neck and slanting of
the head.
• It may be due to injury to the sternocleidomastoid
muscle or avulsion of the accessory nerve at the time
of birth and unilateral fibrosis in the muscle, which
cannot lengthen with the growing neck (congenital
torticollis)
• Variants: Congenital and Acquired
Acquired Torticoils
• Relatively common in children
• The most common causes include upper
respiratory infections, minor trauma, cervical
lymphadenitis and retropharyngeal abscess
• What is the next step in management of
patient? - Cervical spine radiographs should
be obtained in children with acquired
torticollis to ensure there is no cervical spine
fracture or dislocation
Congenital Torticollis
•Caused by shortening one
of SCM muscles
•The most common type
results from a fibrous
tissue tumor-like lesion
that develops in the
sternocleidomastoid before
or shortly after birth.
•The lesion, like a normal
unilateral
sternocleidomastoid
contraction, causes the
head to tilt toward, and the
face to turn away from, the
affected side
Congenital Torticollis
When torticollis occurs prenatally,
the position of the infant's head
usually necessitates a breech
delivery.
Occasionally, the sternocleidomastoid is
injured when an infant's head is pulled too
much during a difficult birth, tearing its fibers
(muscular torticollis).
A hematoma occurs that may
develop into a fibrotic mass that
entraps a branch of the spinal
accessory nerve (CN XI) and thus
denervates part of the
sternocleidomastoid.
Congenital Torticollis
Surgical release of the
sternocleidomastoid
from its inferior
attachments to the
manubrium and
clavicle inferior to the
level of accessory
nerve (CN XI) may be
necessary to enable
the person to hold and
rotate the head
normally.
Eagle’s syndrome
• Elongation of the styloid process or excessive
calcification of the styloid process or stylohyoid ligament
that causes neck, throat, or facial pain and
dysphagia (difficulty in swallowing).
• The pain may occur due to compression of the
glossopharyngeal nerve, which winds around the styloid
process or stylohyoid ligament as it descends to supply
the tongue, pharynx, and neck.
• Pain may be caused by pressure on the internal and
external carotid arteries by a deviated and elongated
styloid process.
• Treatment is styloidectomy.
Patient suffering from Eagle's syndrome
complains of
• a) Burning sensations in mouth
• b) Excessive salivation
• c) Glossodynia
• d) Dysphagia
Lesions of Accessory nerve (CN XI)
IJV
ICA
Accessory n.
Sternocleidomastoid
Trapezius
 Exits cranial cavity through jugular foramen
 Runs obliquely across the lateral aspect of neck
 Motor innervation to sternocleidomastoid + trapezius mm.
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Lesion of the accessory nerve
• Lesion of the accessory nerve in the neck
denervates the trapezius, leading to
atrophy of the muscle.
• It causes a downward displacement or
drooping of the shoulder
• Decreased ability to turn head (due to
dysfunction of SCM!)
• A patient is stabbed in the neck. You suspect
damage to the accessory nerve in the posterior
triangle. You would test nerve function by
asking the patient to
• a) extend their neck against resistance.
• b) extend their neck without impairment.
• c) lift their shoulders against resistance.
• d) lift their shoulders without impairment.
• The accessory nerve supplies muscles
which flex the neck and elevate the
shoulders. Wherever possible, it is
advantageous to test muscle action
against resistance to eliminate 'trick'
movements the patient may have
developed, and to make the muscle stand
out or become palpable.
Subclavian steal syndrome
• cerebral and brain stem ischemia caused by reversal of
blood flow from the basilar artery through the vertebral
artery into the subclavian artery in the presence of
occlusive disease of the subclavian artery proximal to
the origin of the vertebral artery.
• When there is very little blood flow through the vertebral
artery, it may steal blood flow from the carotids and
divert it through the vertebral artery into the subclavian
artery and into the arm, causing vertebrobasilar
insufficiency and thus brain stem ischemia and stroke.
• Symptoms: dizziness, ataxia, vertigo, visual disturbance,
motor deficit, confusion, aphasia, headache, syncope,
arm weakness, and arm claudication with exercise.
• Can be treated by a carotid-subclavian bypass
Subclavian Artery: 1st Part
3 branches:
1.
●
Vertebral a.
2.
●
Internal thoracic a.
3.
●
Thyrocervical trunk:
•
•
•
inferior thyroid a.
transverse cervical a.
suprascapular a.
Thyrocervical
trunk
Vertebral a.
Internal thoracic a.
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Vertebral Artery
Vertebral a.
 1st branch of 1st part of subclavian a.
 Goes through transverse foramina of C1-C6
 Enters cranial cavity through foramen mangnum
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B
E
FD
C
A
• A 44-year-old man complains of recurrent
syncope associated with upper extremity
exercise. What is the MOST likely cause?
(A) Trigeminal neuralgia
(B) Hypoglycemia
(C) Carotid sinus syncope
(D) Subclavian steal syndrome
(E) Vasovagal syncope
How do you confirm that?
Angiography, Doppler Ultrasound examination of neck vessels
Vasovagal syncope occurs when your body overreacts to
certain triggers, such as the sight of blood or extreme
emotional distress.
• The vasovagal syncope trigger causes a sudden drop in
your heart rate and blood pressure. That leads to reduced
blood flow to your brain, which results in a brief loss of
consciousness.
Symptoms:
• Skin paleness, Lightheadedness
• Tunnel vision
• Nausea
• Feeling of warmth
• A cold, clammy sweat
• Yawning
• Blurred vision
• During a vasovagal syncope episode, bystanders may
notice:
• Jerky, abnormal movements
• A slow, weak pulse
• Dilated pupils
• Carotid sinus syncope is a temporary loss of
consciousness or fainting caused by
diminished cerebral blood flow. It results from
hypersensitivity of the carotid sinus, and
attacks may be produced by pressure on a
sensitive carotid sinus such as taking the
carotid pulse near the superior border of the
thyroid cartilage.
Carotid Sinus and Carotid Body
Carotid sinus:

Dilation at the common carotid bifurcation

Baroreceptor (monitors changes in blood pressure)

Innervation: Glossopharyngeal n. (CN IX)
Carotid body:

Collection of receptors at the common carotid
bifurcation

Chemoreceptor (monitors changes in O2/CO2 levels
in blood)

Innervation: Glossopharyngeal n. (CN IX) and
Vagus n. (CN X)
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Central venous line
• Central venous line is an intravenous needle and catheter
placed into a large vein such as the internal jugular or
subclavian vein to give fl uids or medication.
• A central line is inserted in the apex of the triangular
interval between the clavicle and the clavicular and
sternal heads of the sternocleidomastoid muscle into the
internal jugular vein through which the catheter is threaded
into the superior vena cava (a large central vein in the chest).
• The needle is then directed inferolaterally. Air embolism or
laceration of the internal jugular vein is a possible
complication of catheterization.
• A central line may also be inserted into the retroclavicular
portion of the right subclavian vein , and it should be
guided medially along the long axis of the clavicle to reach the
posterior surface where the vein runs over the first rib.
• The lung is vulnerable to injury, and pneumothorax and
arterial puncture, causing hemothorax, are potential
complications of a subclavian catheterization.
Point for
insertion
of
needle
Please watch for details :
http://www.youtube.com/watch?v=0EPTfXx0Np8
Tracheotomy
• Tracheotomy (tracheostomy) is the
procedure of creating an opening through
the trachea by first making an incision
between the third and fourth rings of
cartilage to allow entry of a tube into the
airway, usually as an emergent procedure
to re-establish airway or in a patient who
has been on life support for a prolonged
period of time with an endotracheal tube
and to decrease the risk of tracheomalacia
http://www.youtube.com/watch?v=6_0bH6KxPYA
Cricothyrotomy
• Incision through the skin and cricothyroid
membrane and insertion of a tracheotomy tube
into the trachea for relief of acute respiratory
obstruction. When making a skin incision, care
must be taken not to injure the anterior jugular
veins, which lie near the midline of the neck.
• It is preferable for nonsurgeons to perform a
cricothyrotomy for emergency respiratory
obstructions!
Horner’s syndrome
• This syndrome is characterized by presence of
ptosis, miosis, enophthalmos, anhidrosis, and
vasodilation
• Horner’s syndrome is caused by:
thyroid carcinoma, which may cause a lesion of
the cervical sympathetic trunk;
Pancoast’s tumor at the apex of the lungs, which
injures the stellate ganglion;
Penetrating injury to the neck, injuring cervical
sympathetic nerves.
Cervical Sympathetic Trunk
 Anterior to longus colli and longus
capitis mm.
Longus capitis
 Posterior to CCA in carotid sheath,
and ICA
 Connected to cervical spinal nn. by gray
rami communicantes (GRC)
 Three associated ganglia:

superior

middle

inferior
 Cervical ganglia receive pre-ganglionic
sympathetic fibers from upper thoracic
(T1-T5) spinal cord segments
Sympathetic
trunk
Longus colli
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Superior Cervical Ganglion
To internal carotid plexus

C1-C4 spinal cord segments

Branches pass to…
Superior cervical ganglion
To carotid body and sinus
C1
C2
●
cervical spinal nn. C1-C4
through
gray rami
To external carotid plexus
communicantes (GRC)
C3
GRC
C4
●
ICA and ECA, forming
around these
●
pharynx
●
heart via superior cardiac
Sympathetic trunk
ganglionic fibers)
plexuses
arteries
nn. (post-
Superior cardiac n.
56
Middle Cervical Ganglion

C5-C6 spinal cord segments

Branches pass to…
●
cervical spinal nn. C5-C6
through
gray rami
communicantes (GRC)
●
nn. (post-
heart via middle cardiac
ganglionic fibers)
GRC
Middle cervical ganglion
C5
C6
Middle cardiac nerve
Sympathetic trunk
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Inferior Cervical Ganglion
 C7-C8 spinal cord segments
 Stellate ganglion: C7-T1 spinal cord segments
 Anterior to neck of rib 1 and C7 transverse
process
 Posterior to subclavian and vertebral aa.
 Branches go to…
● cervical spinal nn. C7-T1 through gray
rami communicantes (GRC)
● vertebral a. and form a plexus around
the vessel
● heart via inferior cardiac nn. (postganglionic fibers)
 May occasionally receive white rami
communicantes from T1(2) spinal nn.
Subclavian a.
Vertebral a.
C7
GRC
C8
Inferior cervical ganglion
T1
Inferior cardiac n.
Sympathetic trunk
Ansa subclavia
(connection between58middle
and inferior cervical ganglia)
Horner’s syndrome can result from a
lesion anywhere along a three
neuron sympathetic pathway that
originates in the hypothalamus:
Mem: HORNY PAMELa:
Ptosis Anhidrosis Miosis
Enophthalmos Loss of
ciliospinal reflex
A 56-year-old male smoker is being evaluated for
right shoulder pain. You suspect a malignancy in
the location marked by a star below. Which of
the following additional findings is likely to also
be present in this patient as a result of local
tumor extension?
A. Bitemporal hemianopsia
B. Unilateral deafness
C. Ptosis
D. Horizontal nystagmus
E. Anosmia
Stellate ganglion block procedure
• Indications for procedure:
1. Reflex sympathetic dystrophy - a "short circuit" in the
nervous system causes overactivity of the sympathetic
(unconscious) nervous system which affects blood
flow and sweat glands in the affected area. Signs:
hyperhidrosis (excessive sweating), refractory chest
pain , phantom limb pain, herpes zoster (shingles),
and pain of the head and neck.
2. Arterial vascular insufficiency: These conditions
include Raynaud syndrome, scleroderma, obliterative
vascular diseases, vasospasm, trauma, and emboli.
Reflex sympathetic dystrophy
Inferior Cervical Ganglion
 C7-C8 spinal cord segments
 Stellate ganglion: C7-T1 spinal cord segments
 Anterior to neck of rib 1 and C7 transverse
process
 Posterior to subclavian and vertebral aa.
 Branches go to…
● cervical spinal nn. C7-T1 through gray
rami communicantes (GRC)
● vertebral a. and form a plexus around
the vessel
● heart via inferior cardiac nn. (postganglionic fibers)
 May occasionally receive white rami
communicantes from T1(2) spinal nn.
Subclavian a.
Vertebral a.
C7
GRC
C8
Inferior cervical ganglion
T1
Inferior cardiac n.
Sympathetic trunk
Ansa subclavia
(connection between63middle
and inferior cervical ganglia)
Stellate ganglion block procedure
• Injection of local anestetic (lidocain)
• Performed under fluoroscopy by inserting the
needle at the level of the C6 vertebra to avoid
piercing the pleura, although the ganglion lies at
the level of the C7 vertebra. The needle of the
anesthetic syringe is inserted between the trachea
and the carotid sheath through the skin over the
anterior tubercle of the transverse process of the
C6 vertebra (Carotid tubercle) and then directed
medially and inferiorly. Once needle position close
to the ganglion is confirmed, the local anesthetic is
injected beneath the prevertebral fascia.
Superior Vena Cava Syndrome
• Tumor of lung apex or neck tumors may
invade superior vena cava
Superior Vena Cava Syndrome
Superior Vena Cava Syndrome
• Superior vena cava provides the venous drainage of
head, neck, upper trunk and upper extremities.
• The superior vena cava is a 6-8 cm long vein that
drains into the right atrium. It is located in the medial
mediastinum and is surrounded by the sternum,
trachea, right bronchus aorta, and pulmonary artery. It
is located in close proximity to the perihilar and
paratracheal lymph nodes. This vein has thin walls
and is easily compressed by mediastinal masses.
• Bronchogenic carcinoma is the most common cause
of superior vena cava syndrome. Non-Hodgkin
lymphomas are the second most common cause.
Patients with SVC syndrome complain of dyspnea,
cough, and swelling of the face, neck and upper
extremities. Headaches, dizziness and visual
disturbances may occur due to elevated intracranial
pressure. Dilated collateral veins may be seen in the
upper torso.
• A 56-year-old smoker with recurrent hemoptysis
presents to your office complaining of headaches.
Physical examination reveals facial swelling,
conjunctival edema and dilated vessels of the neck
and upper trunk. Heart sounds are clear. This
patient’s condition is most likely caused by:
• A. Pericardial effusion
• B. Pleural effusion
• C. Superior sulcus tumor
• D. Mediastinal mass
• E. Hormone secretion
• F. Autoimmune disease
• G. Airway obstruction