Anatomy

1. THE
POSTERIOR
NECK
TRIANGLES
Miheso C Lemashon
BSc Anatomy (Hons), MBChB (CT)
January 2024

2. Learning objectives
1. Describe the fascial organization of the neck
2. Outline the division of the neck into triangles
3. Study the boundaries and subdivisions of the posterior triangle of the neck
4. Describe the contents of the posterior neck triangle
5. Study the boundaries and contents of the suboccipital triangle

3. Fascial Organization of the neck
 Superficial neck fascia
• Platysma
• Superficial veins (EJV)
• Superficial lymph vessels
• Cutaneous nerves (Erb’s point?)
• Fat

4. Fascial Organization of the neck
 Superficial neck fascia
• Platysma
• Superficial veins (EJV)
• Superficial lymph vessels
• Cutaneous nerves (Erb’s point?)
• Fat

5. Fascial Organization of the neck
 Deep neck fascia
• Investing fascia (rule of 2s)
• Pretracheal fascia
• Prevertebral fascia
• Carotid sheath
• Spaces

6. Fascial Organization of the neck
 Deep neck fascia
• Investing fascia
• Pretracheal fascia
• Prevertebral fascia
• Carotid sheath
• Spaces (retropharyngeal,
danger, pretracheal)
• Modifications?

7. Triangles of the neck

8. Posterior Triangle of the neck
 Boundaries
 Anterior: SCM
 Posterior: Trapezius
 Inferior: Middle 1/3 of clavicle
 Roof: Skin, superficial fascia and the investing layer of
deep cervical fascia
 Floor: Prevertebral fascia overlying splenius capitis,
semispinalis capitis, levator scapulae, scalenus medius
and scalenus anterior
 Subdivisions – occipital,
supraclavicular

9. Occipital Triangle
 Boundaries
 Anterior: SCM
 Posterior: Trapezius
 Inferior: Inferior belly of omohyoid
 Contents
 CN XI
 Cutaneous and muscular branches of the
cervical plexus
 Supraclavicular nerve
 Transverse cervical vessels

10. Supraclavicular Triangle
 Boundaries
 Anterior: SCM
 Superior: Inferior belly of omohyoid
 Inferior: Middle 1/3 of clavicle
 Contents
 Subclavian artery (third part)
 Trunks of brachial plexus
 Nerve to subclavius
 Lymph nodes

11. Summary – Posterior neck triangles

12. Interscalene Triangle
 Boundaries
 Anterior: Anterior scalene
 Posterior: Middle scalene
 Inferior: 1st rib
 Contents
 Brachial plexus roots
 Subclavian artery

13. Subclavian Artery

14. Suboccipital Triangle
 Boundaries
 Superolateral: Obliquus capitis superior
 Superomedial: Rectus capitis posterior major
 Inferomedial: Obliquus capitis inferior
 Contents
 VA III
 Suboccipital nerve
 Atlantooccipital membrane
 Posterior arch atlas

15. Suboccipital Triangle

16. THE
ANTERIOR
NECK
TRIANGLES

17. Learning objectives
1. Describe the boundaries and subdivisions of anterior neck triangles
2. Outline the location and contents of suprahyoid and infra-hyoid neck spaces
3. Describe the level of organization of cervical lymph nodes
4. Describe location, distribution and relevance of Ansa cervicalis
5. Study the carotid and subclavian arterial system
6. Describe the position, parts, relations and blood supply of thyroid gland
7. Study the boundaries of vertebral triangle and thoracic outlet

18. Anterior neck triangles
• BOUNDARIES
• Anteriorly- median line of the neck,
• Posteriorly-anterior margin of sternocleidomastoid.
• Base -inferior border of the mandible
• •and its projection to the mastoid process,
• •and its apex is at the manubrium sternum.
• Made of suprahyoid and infrahyoid areas above and below the hyoid bone,
• TRIANGLES HERE ARE:
• Digastric/submandibular
• Submental
• Muscular
• Carotid triangles
• By passage of digastric and omohyoid across the anterior triangle

19. Anterior neck triangles

20. Triangles of the neck

22. Lymph drainage of the head and neck

23. Ansa cervicalis

24. Subclavian Artery

25. Subclavian artery

26. Thyroid gland
• Lobes
• The capsule composed of:
oTrue capsule
oFalse capsule
• Suspensory ligament of Berry

27. Relations

28. Blood supply

29. Midline Head and
Neck: Pharynx and
Larynx

30. Learning objectives
1. Describe the parts, relations, neurovascular supply and lymphatic drainage of pharynx
2. Outline the features of the walls of the nasopharynx
3. State the relations and blood supply of palatine tonsils
4. Describe the components of Waldeyer’s ring
5. Study the main parts of the laryngeal cavity
6. Describe the main cartilages, ligaments and muscles of larynx
7. Understand the neurovascular supply of larynx
8. State the extents, relations and neurovascular supply to cervical esophagus and trachea

31. Pharynx
 Parts
 Nasopharynx
 Oropharynx
 Laryngopharynx

32. Nasopharynx
 Boundaries
 Superior: Skull base (basisphenoid and basiocciput)
 Inferior: Soft palate
 Anterior: Nasal cavity via choanae
 Posterior: Posterior pharyngeal wall
 Lateral: Medial pterygoid plate and sup. pharyngeal constrictor
 Roof
 Pharyngeal tonsil
 Lateral wall
 Tubal tonsil
 Salpingopharyngeal fold
 Fossa of Rosenmuller
 Eustachian tube

33. Nasopharynx

34. Oropharynx
 Boundaries
 Superior: Soft palate + Pharyngeal isthmus
 Inferior: Continuous with laryngopharynx (level of tip of epiglottis)
 Anterior: Oral cavity via oropharyngeal isthmus
 Posterior: Posterior pharyngeal wall
 Lateral wall
 Palatine tonsil in tonsillar fossa

35. Palatine tonsil
 Blood supply
 Facial artery (tonsillar branch)
 Lingual artery
 Pharyngeal artery
 Ascending palatine artery
 Ascending pharyngeal artery

36. Laryngopharynx/Hypopharynx
 Boundaries
 Superior: Level of tip of epiglottis and pharyngoepiglottic fold
 Inferior: Level of cricopharyngeus
 Anterior: laryngeal inlet
 Posterior: Posterior pharyngeal wall

37. Muscles of the pharynx

38. Muscles of the pharynx

39. Pharynx

40. Waldeyer’s Ring

41. Larynx

42. Laryngeal cavity

43. Larynx

44. Larynx

45. Larynx

46. THANK YOU