12/2/2014 Gross Anatomy Superior Mediastinum and Root of the Neck Matthew J. Vilburn Flashcards
What are the major divisions of the mediastinum?
- Superior
- Inferior
- Anterior
- Middle
- Posterior
What do you find in the posterior mediastinum?
- Azygos venous system
- Sympathetic trunk
- Splanchnic nerves
- Thoracic duct
What do you find in the superior mediastinum?
Major junction of many structures from the neck and thorax • Trachea • Esophagus • Subclavian veins • Aortic arch & branches • Phrenic & vagus nerves • Recurrent laryngeal nerves
Why do we care about the mediastinum?
- recurrent laryngeal nerve injuries
- aortic aneurysms
- myasthenia gravis
- variations in the great arteries
Describe the neck and its function
• Fibromuscular tube • Passageway for: - Respiratory system - Digestive system - Brachial plexus • Connects the head with the thorax
What are the bones in the neck?
• 7 cervical vertebrae
- all movement of the neck involve the cervical vertebrae
• Hyoid bone
- attachment for muscles of the tongue and pharynx
What are the triangles of the neck?
• sternocleidomastoid
- divides the superficial anterior neck into two triangles
• posterior/lateral triangle
• anterior triangle
What are the primary contents of the posterior triangle?
- CN XI Accessory
- Cervical plexus
- Phrenic nerve
- Brachial plexus
What are boundaries of the posterior triangle?
- Posterior border of the sternocleidomastoid
- Anterior border of trapezius
- Middle portion of clavicle
What are the primary contents of the anterior triangle?
- Hyoid Bone
- Thyroid & cricoid cartilages
- Trachea
- Thyroid & submandibular glands
What are boundaries of the anterior triangle?
- Anterior boundary of sternocleidomastoid
- Mandible
- Midline from chin to sternum
What are the contents of the carotid triangle?
- Common carotid artery
- Internal & external carotid arteries with branches
- Internal jugular vein
- Vagus, spinal accessory, & hypoglossal nerves
Describe the carotid triangle
A subdivision of the anterior triangle between the omohyoid, digastric and sternocleidomastoid muscles
What are the 5 muscles into which the anterior neck can be divided?
- Superficial
- Infrahyoid
- Suprahyoid
- Lateral vertebral
- Anterior vertebral
What are the superficial muscles of the neck?
• Platysma - thin muscle attached to the skin of the neck • Trapezius - moves the scapulae • Sternocleidomastoid - 2 heads: Sternal & clavicular
What is the function of the suprahyoid muscle?
Help with swallowing and movement of the tongue
What is the function of the infrahyoid muscle?
Help with movement of the hyoid bone during swallowing
What muscles form the suprahyoid muscle?
- Mylohyoid
- Geniohyoid
- Stylohyoid
- Digastric
What muscles form the infrahyoid muscle?
- Omohyoid
- Sternohyoid
- Thyrohyoid
- Sternothyroid
What is the function of the anterior vertebral muscle?
The prevertebral muscles all attach on the anterior portion of the neck
What muscles form the anterior vertebral muscles?
- Longus colli
- Longus capitis
- Rectus capitis anterior
- Rectus capitis lateralis
What muscles form the lateral vertebral muscles?
• Scalene Triangle
- Anterior scalene
- Middle scalene
- Posterior scalene
What is important about the anterior scalene muscle?
- The subclavian vein & phrenic nerve pass anterior to this muscle
- The subclavian artery passes posteriorly and can be divided into thirds by this muscle
What arteries are found in the neck?
• Brachiocephalic Trunk - Right common carotid - Right subclavian • Left common carotid • Left subclavian
Internal carotid supplies the ___
brain & eye
External carotid supplies the ___
face & neck
Subclavian artery supplies the ___
lower neck & upper limb
Is the vertebral artery a branch from the subclavian?
Yes
What are the external carotid branches?
*Seven Angry Ladies Fight Over PMS
- Superior Thyroid
- Ascending Pharyngeal
- Lingual
- Facial
- Occipital
- Posterior Auricular
- Maxillary
- Superficial Temporal
What are the 3 parts of the subclavian artery?
• 1st : Vertebral artery, Thyrocervical trunk, Internal thoracic artery - Suprascapular artery - Cervicodorsal trunk - Dorsal scapular* - Superficial cervical • 2nd: Costocervical trunk - Supreme intercostal artery - Deep cervical artery • 3rd: None
Anterior & External Jugular veins drain from the neck and face into the ___ vein
Subclavian
___ jugular vein drains blood from the brain, superficial face, and neck
Internal
Subclavian vein drains the ___
upper limbs
The ___ veins are formed by the junction of the internal jugular and subclavian veins
brachiocephalic
What are the nerves running through the neck?
- Sympathetic ganglia
- Cranial nerves
- Recurrent laryngeal
- Cervical plexus
- Brachial plexus
- Phrenic nerve
Why do we care about the neck?
Torticollis Recurrent laryngeal nerve damage Horner's syndrome Central lines in subclavian veins Nerve blocks
