Neck & Posterior Triangle Flashcards
What are the boundaries of the posterior triangle?
Anterior border - Posterior border of the SCM
Posterior border - Anterior border of the trapezius
Inferior border - Mid-3rd of the clavicle
Apex - Superior nuchal line of occipital bone
What are the 3 compartments of the neck and what do each contain?
Visceral (in the mid-line of neck) - contains; trachea, oesophagus, thyroid/ parathyroid glands.
Vascular (2 lateral compartments) - Contains BV - carotid sheath, internal carotid and jugular and vagus nerve.
Vertebral (in mid-line of neck) - LARGE posterior compartment containing cervical spine, muscles and cervical nerves.
What are the attachments (origins) of the SCM?
Sternal head - menubrium of sternum
Clavicular head - superior surface of medial third of clavicle
What is the function of fascia?
Containment. protection and allowing structures to slide during movement
What is superficial fascia, where is it and what does it contain?
THIN fatty neck tissue.
Between dermis and investing deep cervical fascia
Contains - cutaneous nerves, BV, lymphatics and anterolaterally the PLATYSMA MUSCLE.
What are the 3 deep fascia layers?
Investing, pre-tracheal and pre-vertebral
Where is INVESTING layer of deep fascia located?
Completely surrounds neck - deep to skin/ subcutaneous tissue.
‘invests’ (encloses) trapezius and SCM, parotid and submandibular glands.
Pierced by external and anterior jugular veins and cervical plexus nerves.
What are the contents of the posterior triangle?
Spinal accessory nerve
Subclavian artery and vein
Brachial plexus trunks
Omohyoid inferior belly
Transverse cervical nerve
What are the subdivisions of the posterior triangle what muscle splits them?
Occipital triangle
Subclavian (omoclavicular) triangle
Omohyoid
Action of trapezius
Stabilises the scapula
Assists in rotating scapula during abduction of humerus;
upper fibres ELEVATE
middle ABDUCT
lower DEPRESS scapula
Action of SCM
Unilateral - moves head to side (opposite one to muscle that contracts)
Bilateral - moves neck up and down
What is the cervical plexus and what are its cutaneous (superficial) branches and deep (muscular) branches?
Nerve cluster posterior to border of SCM
Cutaneous - lesser occipital, great auricular and transverse cervical, supraclavicular (let’s go to sleep)
Muscular - muscular branches to SCM, prevertebral, levator scapule, ansa cervicalis, phrenic (M (neck, spine, shoulder) AP)
What is the external jugular vein’s function and where does it run?
Drains the blood from brain, parotid gland, most of scalp and side of face.
Drains into SUBCLAVIAN ARTERY (to heart).
Runs ACCROSS SCM.
What is the anterior jugular vein’s function and where does it drain?
Superficial vein that drains anterior aspect of neck.
Drains into the EXTERNAL JUGULAR VEIN
What are the actions of the scalene muscles? (anterior and middle)
They both elevate the first rib and cause flexion of the neck (chin down motion)