POSTERIOR TRIANGLE OF NECK

STEVEN J. ZEHREN, PH.D.

BOUNDARIES OF POSTERIOR TRIANGLE

STERNOCLEIDOMASTOID MUSCLE (SCM)

Sternal head

Clavicular head

Mastoid process

TORTICOLLIS

TRAPEZIUS MUSCLE

SUPERIOR ROTATION OF GLENOID FOSSA

Superior trapezius

Inferior trapezius

Axis of rotation

XI

STERNOCLEIDOMASTOID M.TRAPEZIUS M.

SKELETAL MOTOR --- TO STERNOCLEIDOMASTOID & TRAPEZIUS MUSCLES

XI. SPINAL ACCESSORY N.

ROOFOF POSTERIOR TRIANGLE

Platysma m.

Investing layer ofdeep cervical fascia

FLOOROF POSTERIOR TRIANGLE

Splenius capitis m.

Levator scapulae m.

Post., mid., & ant.scalene mm.

Muscles of floor

MUSCLES OF FLOOR OF POSTERIOR TRIANGLE

FASCIAL FLOOR OF POSTERIOR TRIANGLE

Prevertebral layerof deep cervical fascia

Anterior scalene m.Middle scalene m.

Posterior scalene m.

SCALENE MUSCLES

Rib 1

MUSCLES PRODUCING MOVEMENT OF THE CERVICAL INTERVERTEBRAL JOINTS

VENTRAL RAMI:

INNERVATION OF PREVETEBRAL AND SCALENE MUSCLES

CONTENTSOF POSTERIOR TRIANGLE

CONTENTS OF POSTERIOR TRIANGLE

Great auricular n.

Lesser occipital n.

Accessory n. (XI)

Transverse cervical a.

Omohyoid m.(inferior belly)

Brachial plexus

Subclavian a. (3rd part)

Suprascapular a.

OMOHYOID MUSCLE

OMOHYOID MUSCLE

Omohyoid m. (inferior belly)

Omohyoid (superior belly)

NERVES

F. magnum Jugular f.

C2 spinal n.

C3 spinal n.C4 spinal n.

Acessory n. (XI)

Sternocleidomastoid m.

Trapezius m.

Efferent fibersAfferent fibers

5 Roots(vental rami)

3 Trunks

3 ant. Divisions3 post. Divisions

3 Cords

5 terminal Branches

Musculocutaneous n.

Axillary n.

Radial n.

Median n.

Ulnar n.

C5

C6

C7

C8

T1

“Roger Travis Drinks Cold Beer”

Superior

Middle

InferiorLateral

Posterior

Medial

BRACHIAL PLEXUS IN RELATIONSHIP TO CLAVICLE

Motor NervesTo Prevertebral

Muscles

ContributionsFrom C3 & C4

To XI

CutaneousNerveS

Ansa Cervicalis:

Phrenic Nerve

SUPERIOR ROOT

INFERIOR ROOT

ANSA

XII XI

FIVE COMPONENTS OF CERVICAL PLEXUS:

C1

C2

C3

C4

CUTANEOUS BRANCHES OF THE CERVICAL PLEXUS

Lesser occipital n. (C2,3)

Great auricular n.(C2,3)

Transverse cervical n. (C2,3)

Supraclavicular nn. (C3,4)

CERVICAL PLEXUS

VESSELS

ARTERIES IN POSTERIOR TRIANGLE

1 3

ARTERIES IN POSTERIOR TRIANGLE

TRANSVERSE CERVICAL A.

SUPRASCAPULAR A.

THYROCERVICAL TRUNK

Retromandibular v.

Superficial temporal v. Maxillary v.

Facial v.

Common facial v.(to IJV)

Posterior auricular v.

External jugular v.

Subclavian v.

EXTERNAL JUGUAR VEIN

Anterior jugular v.

Transverse cervical v.

Suprascapular v.

INTERSCALENE TRIANGLE

Anterior scalene m.Middle scalene m.

Brachial plexus

Subclavian a.

BOUNDARIES & CONTENTS OF THE INTERSCALENE TRIANGLE

Rib 1

Anterior scalene m.

Middle scalene m.

Cervical ribcompressessubclavian a.

Lower trunk of brachial plexuselevated by cervical rib

Ascending cervical a.

Anterior scalene m.

Phrenic n.

Inferior thyroid a.

Transverse cervical a.

Suprascapular a.

Thyrocervical trunk

Subclavian v.

ANTERIOR RELATIONSHIPS OF ANTERIOR SCALENE MUSCLE

SUBCLAVIAN VEIN PUNCTURE

Cervical pleura

CERVICAL PLEURA (CUPULA)

DEEP FASCIAE OF NECK

Investing fascia

Prevertebral fascia

Carotid sheath

Pretracheal fascia *

Buccopharyngeal fascia *

Common carotid a.Internal jugular v.Vagus n.

* = Component of visceral fascia

Retropharyngeal space

Buccopharyngeal fascia

Prevertebral fascia

Retropharyngeal space

Base of skull

Mediastinum

END OF LECTURE