Posterior triangle of neck/ Anatomy/ Simplified - Boundaries, Contents & Clinical Anatomy

Опубликовано: 04 Март 2026
на канале: Smart Med Learn Dr. Ankit Jain
30,921
831

Links of other neck triangles videos:

Triangles of neck- Subdivisions & Boundaries/ Anterior and posterior triangle    • Triangles of neck/ Anatomy/ Simplified - S...  

Submental triangle of neck/ Anatomy/ Simplified - Boundaries and contents/ Anterior triangle of neck    • Submental triangle of neck/ Anatomy/ Simpl...  

Digastric (Submandibular) triangle of neck - Boundaries & contents    • Digastric (Submandibular) triangle of neck...  

Carotid triangle of neck- Boundaries & contents
   • Carotid triangle of neck/ Anatomy /Simplif...  

-------------------------------------------------------
like , comment , share , subscribe

To Subscribe our youtube channel, click here -
https://www.youtube.com/c/SmartMedLea...

Telegram group Anatomy knowledge (Smart Med Learn) link:
https://t.me/smartmedlearnsdrankitjain

Facebook page :
  / smartmedlearn  
----------------------------------------------

Posterior triangle of neck

Posterior triangle is the triangular space on the side of neck behind the sternocleidomastoid muscle.

Boundaries
Anterior: Posterior border of sternocleidomastoid muscle.
Posterior: Anterior border of trapezius muscle.
Inferior (base): Superior aspect of middle third of the clavicle.
Superior (apex): Meeting point of sternocleidomastoid and trapezius muscles at the superior nuchal line of the occipital bone.

Roof
It is formed by the investing layer of the deep cervical fascia. The superficial fascia overlying the roof contains platysma, external jugular and posterior jugular veins, and cutaneous nerves and vessels.
Structures piercing the roof of the posterior triangle are:
1. Four cutaneous branches of cervical plexus
(a) Lesser occipital nerve (C2)
(b) Great auricular nerve (C2, C3)
(c) Transverse cervical nerve (C2, C3)
(d) Supraclavicular nerves (C3, C4).
2. External jugular vein

Floor
The floor of posterior triangle is muscular and is formed from above downwards by the:
1. Semispinalis capitis.
2. Splenius capitis.
3. Levator scapulae.
4. Scalenus medius.
5. First digitation of serratus anterior (sometimes).

The muscular floor of posterior triangle is covered by prevertebral layer of deep cervical fascia, which forms the fascial carpet of the floor of the posterior triangle.

Subdivisions
The posterior triangle is subdivided into two parts by the inferior belly of the omohyoid,
a) a larger upper part called occipital triangle
(b) a small lower part called subclavian (supraclavicular) triangle.

Contents
1. In the occipital triangle (i.e., above the omohyoid)
(a) Spinal accessory nerve
(b) 3rd and 4th cervical nerves providing branches to levator scapulae and trapezius muscles
(c) Dorsal scapular nerve (C5)
(d) Four cutaneous branches of cervical plexus (initial parts)
(e) Superficial transverse cervical artery
(f) Occipital artery.
2. In the subclavian/supraclavicular triangle (i.e., below the omohyoid)
(a) 3rd part of the subclavian artery
(b) Subclavian vein
(c) Terminal part of external jugular vein
(d) Trunks of brachial plexus
(e) Lymph nodes.
• All the important contents of the posterior triangle lie deep to the fascial carpet of the floor except spinal accessory nerve, which lies just underneath the roof. In operations on the posterior triangle all the structures except spinal accessory nerve are safe, provided fascial carpet of posterior triangle is left intact.
The point at the junction of the upper and middle third of the posterior border of sternocleidomastoid where four
cutaneous nerves and spinal accessory nerve emerge is termed nerve point of the neck. In ‘cervical plexus nerve block’ the anesthetic agent is injected at this site.

#mbbs #anatomy #smartmedlearn #posteriortriangle #occipitaltriangle #posteriortriangleoftheneck #trianglesofneck #headandneckanatomy #usmlestep1
-----------------------------------------------------------------------------------------------------------------

To watch more videos, please click here:-

Erb's paralysis in Hindi/Brachial Plexus Injury
   • Erb's paralysis/Brachial Plexus Injury/Erb...  

Brachial plexus in Hindi- Roots, Trunks, Divisions, Cords and Branches
   • Brachial plexus / Anatomy / Simplified - R...  

Cubital fossa (Boundaries, contents, and clinical anatomy) in Hindi
   • Cubital fossa / Anatomy/Simplified - Bound...  

Light reflex pathway and lesions in Hindi (Part-1/2) // pupillary light reflex pathway
   • Light reflex pathway and lesions (Part-1/2...  

Visual Pathway and Lesions (Part-1/2) in Hindi
   • Visual Pathway and Lesions (Part-1/2) in H...  

Cerebrum (Part-2/6) in Hindi - Gyri & Sulci on Superolateral surface of cerebral hemisphere, Insula
   • Cerebrum (Part-2/6) in Hindi - Gyri & Sulc...  

Cerebrum (Part-1/6) in Hindi - External Features (Poles, Surfaces, Borders & Lobes)
   • Cerebrum (Part-1/6) in Hindi-External Feat...  

Bell's Palsy (English)
   • Bell's palsy/ Upper and Lower motor neuron...  

Facial Nerve - Functional Components, Course & Branches
   • Facial Nerve - Functional Components, Cour...  


Deep Cervical Fascia - I (Investing Layer)
   • Deep Cervical Fascia - I (Investing Layer)...  

Thank you
Smart Med Learn
Dr. Ankit Jain
MBBS, MS