Ns6 Posterior Triangle Of Neck

Slide 1: Posterior Triangle of Neck Dr. Skantha Kandiah MBA, MSc (NUI), MB BCh BAO (NUI), LRCP & SI Senior Lecturer in Anatomy and Lecturer in Healthcare Management RCSI

Slide 2: Posterior Triangle

Slide 3: Posterior Triangle • Base: Middle 1/3 of the clavicle • Roof: Investing layer of deep cervical fascia • Floor: prevertebral fascia lying on splenius, levator scapulae and scalenus medius

Slide 4: Contents • Upper trunk of Brachial Plexus • Apex of the lung extends to 2cm above the middle 1/3 of the clavicle • Lymph nodes • Subclavian artery – at root of neck • Subclavian vein – at root of neck • External Jugular Vein • Spinal part of XI

Slide 5: External Jugular Vein

Slide 6: XI • Accessory nerve • Spinal and Cranial parts • Spinal part accessory nerve – superficial structure in posterior triangle • 1/3 down the posterior border of SCM to 2/3 down the anterior border of trapezius

Slide 7: XI

Slide 8: XI • SCM • Trapezius • How do you test above muscles? • Spinal and cranial parts

Slide 9: Other Nerves…..

Slide 10: Cervical Plexus: Muscular Branches • Anterior primary rami of the upper cervical nerves form the cervical plexus • ansa cervicalis: C1,2,3 and XII (descendens hypoglossi) • Ansa cervicalis supplies the strap muscles • Phrenic nerve: C3,4,5

Slide 11: Cervical Plexus: Cutaneous Branches • Lesser occipital C2: upper triangle, behind ear • Great Auricular C2,3: skin over parotid • Transverse Cervical C2,3: chin to sternum • Supraclavicular C3,4

Slide 12: Stab Wound to Posterior Triangle • Upper trunk brachial plexus injury • What is it called? • Apex of the lung is here, so what might happen? • Bleeding from?

Slide 13: Sample Question • Describe the boundaries and contents of the posterior triangle of the neck. Explain the consequences of a stab injury to the posterior triangle. Give surface markings of any important structures you name.