Thoracic Outlet Flashcards
Boundaries of thoracic outlet?
- Manubrium
- First rib
- First thoracic vertebrae
Prevertebral muscles?
Lateral:
- Scalenes (anterior, middle, posterior)
- Splenius Capitus
- Levator Scapulae
Anterior and Middle scalenes attachments?
- Transverse process
- 1st rib
Posterior scalene attachments?
- Transverse process
- 2nd rib
Scalenes innervation?
ventral rami
Scalenes function?
- flex neck laterally
- flex head
- raise ribs
Branches of Aortic arch?
- Brachiocephalic trunk off right side
- Right Common Carotid
- Right Subclavian - Left Common Carotid
- Left Subclavian
Branches of Subclavian Artery?
- Vertebral Artery (1st branch)
- Internal Thoracic
- Thyrocervical Trunk
- Inferior Thyroid
- Transverse Cervical (Trapezius)
- Suprascapular (level of clavicle) - Costocervical Trunk
- Superior Intercostal
- Deep Cervical - Dorsal Scapular
Clinical significance of Internal Thoracic Artery?
-used for bypass surgery to maintain blood flow to ventricles
Where does Dorsal Scapular Artery run?
- runs in between trunks of brachial plexus
- supplies Rhomboids
Where does Subclavian Vein run?
- anterior to anterior scalene
- not compromised by scalene interval syndrome
What drains into the Subclavian vein?
- External jugular vein runs superficial to sternocleidomastoid muscle
- Subclavian combines with Internal Jugular
What drains into the Brachiocephalic vein?
-Internal Jugular and Subclavian form it
Where does the brachiocephalic vein drain?
- 2 brachiocephalic veins join to form the Superior Vena Cava
- Left vein crosses the midline
T/F
Thymus is always active.
T
-does regress in size but stays active
Path of Vagus nerve?
- starts as Cranial Nerve 10 off of the brainstem
- goes down the neck along with Internal Carotid Artery and Internal Jugular Vein
- Left side sends a branch that loops under the Aortic arch at the Ligamentum Arteriosum called the Left Recurrent Laryngeal Nerve
- Right Side sends the Right Recurrent Laryngeal Nerve back up and loops under Right Subclavian Artery
Phrenic Nerve?
- C3, 4, 5
- innervates diaphragm
- anterior to anterior scalene
Ligamentum Arteriosum?
- ligament that is remnant of ductus arteriosum
- connects Aorta to Pulmonary Artery
Sympathetic trunk path?
- starts anterior then lateral to vertebral bodies
- ganglia along chain (1 per level)
- Cervical ganglion
- stellate ganglion
- ganglion impar
- ends anterior to sacrum
Where do superficial lymph nodes drain?
- external jugular vein
- anterior jugular veins
Where do deep cervical lymph nodes drain?
-internal jugular vein
Lymphatics in neck?
- Superficial cervical
- deep cervical
- pharyngeal
- pretracheal
- paratracheal
- retropharyngeal
What does the Thoracic duct drain?
- lymph from everything below diaphragm
- everything except right side of head and neck, right upper limb and right side of thorax (right lymphatic duct)
Where does the Thoracic duct drain into?
junction between left Internal Jugular Vein and Subclavian Vein
Cervical viscera?
- Respiratory layer
- larynx
- trachea - Alimentary layer
- pharynx
- esophagus
Cartilage in larynx?
- thyroid
- cricoid (inferior C6)
- arytenoids
Where does the trachea begin?
- after cricoid cartilage
- this marks the end of larynx
What is the trachea?
- conduit from larynx to main bronchi
- 16-20 C shaped rings of cartilage
Location of C shaped rings in trachea?
- anterior side
- posterior side is smooth muscle to allow movement of bolus down esophagus without pain sensation
Where is the pharynx and esophagus located?
-posterior to larynx and trachea
Divisions of the pharynx?
- Nasopharynx
- Oropharynx
- Laryngopharynx
Muscles of the pharynx?
Pharyngeal Constrictors:
- superior
- middle
- inferior
Where is the landmark for the end of the pharynx and larynx?
- Cricoid cartilage
- beginning of esophagus and trachea
What is the esophagus?
- continuation of pharynx inferior to cricoid cartilage (C6 vertebral level)
- conduit from pharynx to stomach
Where do the brachial plexus and Axillary Artery run in relation to scalene muscles?
-in between anterior and middle scalenes
Where does the Axillary vein run in relation to Scalene muscles?
-anterior to anterior scalene
Prefixed brachial plexus?
-C4-C8
Postfixed brachial plexus?
- C6-T2
- lower syndrome
- ulnar nerve problems
Cervical rib?
- bilateral or unilateral
- fuses with 1st rib
- restricts space of Subclavian Artery
Thoracic Outlet syndrome?
Injury to structures between anterior and middle scalene:
- Brachial Plexus and Subclavian Artery
- Scalenus Anticus Syndrome
- Cervical Rib syndrome
- Costoclavicular syndrome
- surgery as intervention, maybe OMM
Superior Brachial Plexus Injury?
- C5-C6
- limb hangs by side
- medial rotation
- Erb-Duchenne Palsy (waiters tip)
- could be from trauma or pulling baby out
Inferior Brachial Plexus injury?
- C8-T1
- see more often in thoracic outlet syndrome
- hyperflexion
- claw hand
- could be from pulling on baby’s arm at birth, climbing
