Class 1 Flashcards
Superficial cervical fascia
Platysma
Superficial vv
Cutaneous nn
Superficial cervical LNs
Platysma
Origin: Deep fascia covering deltoid & pectoralis major.
*Insertion: -Lower border of mandible body. -Blends with mouth angle muscles. -Interlace with opposite side.
*N. supply: Cervical branch of facial n. *Action: Assists in mandible depression, depresses mouth angle & wrinkles neck skin
Superficial vv
External jugular vein (E.J.V) & its tributaries
Cutaneous nn
Cutaneous branches of cervical plexus;
1-Great auricular n
2-Lesser occipital n
3-Transverse cutaneous n neck
4-Supraclavicular nn
Superficial cervical lymph nodes
Superficial to sternomastoid muscle
Receive from occipital and mastoid node
and send to deep cervical deep to the sternomastoid
Deep investing fascia
Surrounds whole neck & splits to envelop trapezius & sternomastoid
Relations of the deep investing fascia
Post.: Continuous with ligamentum nuchae & C 7 spine, then splits to surround trapezius & forms post. triangle roof
Lat, & ant.: Splits again to surround sternomastoid, then it roofs ant. triangle & becomes continuous with corresponding fascia of opposite side. In middle, it is attached to symphysis menti, hyoid body & manubrium sterni.
Sup.: Attached to external occipital protuberance, sup. nuchal line, mastoid process & mandible lower border. Between mandible angle & mastoid process, it splits to cover parotid gland forming parotid fascia; superficial layer is fixed to zygomatic arch & deep layer to styloid process & tympanic plate. Part of parotid fascia from styloid process to mandible angle is thickened forming stylomandibular ligament.
Inf.: Attached to acromion, clavicle & manubrium. Short distance above sternum, it splits into 2 layers enclosing supra-sternal space which contains; lower ends of ant. jugular veins, jugular arch connecting both ant. jugular veins, sternal head sternomastoid & some LN’s
Structures piercing investing fascia
EJV, pierces it 1 inch above clavicle. -Ant. facial v., pierces it 1 finger below mandible -All cervical plexus cutaneous branches
Prevertebral Fascia
Covers prevertebral muscles & extends from skull base (above) to 3RD thoracic vertebra (below). *Lat. it covers scalenus ant. & post. triangle floor muscles, then it fades under trapezius. *As subclavian vessels & brachial plexus trunks emerge from beneath it’s lat. border, they take tube from it called axillary fascia
Pretracheal Fascia
Deep fascia lying infront & on sides of trachea, it splits to invest thyroid gland connecting it to larynx cartilages (thyroid & cricoid). That is why thyroid gland moves up & down with larynx during swallowing.
*Lat. it blends with carotid sheath, while inf. it invest inf. thyroid vv. to become continuous with fibrous pericardium inside thoracic cavity
Carotid Sheath
Deep fascia tube, investing big vessels & nn. of neck except E.C.A, extends from skull base above (tympanic plate & petrous part of temporal bone) till neck root below. Ant. continuous with pretracheal fascia & post. with prevertebral fascia.
*Contents: 1-Common & internal carotid arteries (med.). 2-I.J.V (lat.) 3-Vagus n. in between & slightly post. 4-Sympathetic chain embedded in post. wall & ansa
cervicalis in ant. wall.
N.B.: Sheath upper part (above digastric post. belly) contains lower 4 cranial nn., while sheath lower part contains vagus n. only. *Relations: a)Ant.; -muscles: Sternomastoid & infrahyoid. -Gland: Thyroid lobe -Veins: Sup. & middle thyroid. b)Post.; -Cervical vertebrae, prevertebral muscles & fascia.
-Arteries: Vertebral & inf. thyroid c)Med.; -Larynx & pharynx (above).
-Trachea, esophagus & recurrent laryngeal n. (below)
Posterior triangle boundaries
Ant.; post. border sternomastoid -Post.; ant. border trapezius. -Below (base); middle 1\3 clavicle -Above (apex); attachment of sternomastoid & trapezius to sup. nuchal line of occipital bone.
*Roof: -Skin -Superficial fascia; containing platysma & E.J.V.
-Deep investing fascia; pierced by EJV (1 inch above clavicle), cervical plexus cutaneous
branches (at middle of sternomastoid post. border) & supraclavicular nn. (just above clavicle). Spinal root accessory n. is embedded in it.
*Floor: -Muscles (from below); scalenus medius, levator scapulae & splenius capitis. -Deep (prevertebral) fascia; covering muscles of floor
Contents
Muscle
Inf. belly
omohyoid;
slender
muscle 2 1/2
cm above
clavicle,
divides
triangle into:
Subclavian (supraclavicular)
below & occipital above
Nerves
Trunks of brachial plexus;
upper, middle & lower in lower part triangle
Cutaneous branches of cervical plexus; appear at middle of sternomastoid post. border & pierce roof deep fascia to supply skin: *Lesser occipital (C2); ascends along sternomastoid post. border to skin on scalp back & upper 1/3 of auricle back.
*Great auricular (C2,3); runs upwards & forwards on sternomastoid to skin on parotid, mandible angle, mastoid process, lower 1/3 of auricle lat. surface & lower 2/3 of it’s med. surface.
*Transverse cut. n. neck (C2,3); runs transversely
across sternomastoid towards midline & divides into upper & lower branches to neck ant. part. *Supraclavicular (C3,4); descends as 3 branches which pierce roof deep fascia a little above clavicle, then cross clavicle to skin of chest as far as sternal angle & upper 1/2 deltoid.
Muscular branches of cervical plexus; to sternomastoid, trapezius, levator scapulae, scalene muscles & diaphragm (phrenic n.)
Spinal root accessory n.; appears at middle of sternomastoid post. border, passes downwards & backwards over levator scapulae (in deep fascia of roof) to disappear undercover of trapezius(5 cm above clavicle). It supplies sternomastoid & trapezius
Arteries
1-3rd part subclavian a.;
in lower part of triangle infront of brachial plexus lower trunk
2-Suprascapular a.;
branch of thyro-cervical trunk (1st part subclavian a.).Crosses triangle very close to clavicle
3-Transverse cervical a.;
branch of thyro-cervical trunk (1st part subclavian a.). Crosses triangle above suprascapular a., ending at levator scapulae ant. border, by dividing into superficial & deep branches
