Cervical Fascia Anatomy Lecture

Introduction

• Lecturer: Dr. Morton
• Goal: Understand cervical fascia, its anatomy, and clinical importance.
• Topics Covered:
  • Definition of fascia
  • Superficial and deep fascial planes
  • Retro-pharyngeal and danger spaces

What is Fascia?

• Origin: Latin for a band or bandage.
• Structure: Strands or sheets of fibrous or collagenous connective tissue.
• Function: Wraps around the anatomy, forming compartments.

Importance of Cervical Fascia

• Anatomical Importance: Forms concentric layers compartmentalizing neck anatomy (muscular, vascular, and visceral compartments).
• **Clinical Importance: **Surgical orientation, disease spread (e.g., cancer, infection), relevance in ENT surgery, and radiology.

Orientation of Study

• Section Level: C6 level, with the top being anterior and the bottom posterior.

Types of Fascia

Superficial Fascia

• Location: Subcutaneous tissue around the circumference of the neck, continuous throughout the body
• Contains:
  • Platysma Muscle: From the corner of the mouth to the clavicle and pectoralis major.
  • Cutaneous veins, arteries, and nerves: Branches from the cervical plexus.

Deep Fascia

• Location: Encases muscles, vessels, and viscera, enabling structures to slide over each other.
• **Subdivisions: **
  1. Deep Investing Fascia:
  • Encircles the entire neck, envelops the sternocleidomastoid and trapezius muscles.
  • Forms the roof of the posterior triangle (space between sternocleidomastoid and trapezius).
  • Pierced by cutaneous branches of the cervical plexus and external jugular vein.
  • Boundaries: Mandible, hyoid, sternum (front); clavicle, scapula (side); occipital bone, nuchal ligament, trapezius (back).
  2. Pretracheal Fascia:
  • Visceral Compartment: Contains thyroid gland, trachea, recurrent laryngeal nerves, esophagus, and pharynx.
  • Posterior Border: Buccopharyngeal fascia (envelops buccinator and pharyngeal constrictors).
  • Boundaries: Hyoid and laryngeal cartilages (front), fuses with the pericardial sac (posterior), courses from the skull down to the mediastinum.
  3. Prevertebral Fascia:
  • Muscular Compartment: Contains vertebral column, longus colli, longus capitis, scalene muscles, levator scapulae, and paraspinals.
  • Contains: Sympathetic trunk, phrenic nerve, cervical and brachial plexuses.
  • Forms the axillary sheath, envelops brachial plexus, subclavian, and axillary artery.
  • Subdivision: Alar fascia (anterior layer fusing with the buccopharyngeal fascia around T1-T4).
  4. Carotid Sheath:
  • Formed by adjacent fascial sleeves (deep investing, prevertebral, pretracheal).
  • Contains: Internal jugular vein, carotid arteries, vagus nerve, deep cervical nodes, carotid sinus nerves.
  • Ansa Cervicalis: Found within the sheath.
  5. Fascia around Infrahyoid Muscles:
  • Different categorization across references: pretracheal fascia or deep investing fascia.

Anatomical Spaces and Clinical Relevance

• Spaces defined by fascial layers—closed in health, can expand in infections.
• Retro-pharyngeal and Danger Spaces: Main spaces discussed.
  • Retro-pharyngeal Space: Between buccopharyngeal and alar fascia
    • Permits movement of pharynx, larynx, and esophagus during swallowing.
    • Clinical Relevance: Infections can restrict swallowing/breathing and may spread to the mediastinum.
  • Danger Space: Between alar and prevertebral fascia.
    • Runs from skull to posterior mediastinum.

Summary

• Clinical Terminology Variation: Different terms used by clinicians (superficial, middle, deep layers).
• **Key Points: **
  • Diversity in terminology and description between anatomists and radiologists.
  • Radiologists often have their own jargon.

Remember: Dr. Morton's overview of the cervical fascia is crucial for understanding its anatomical and clinical significance. This foundation aids in grasping how infection can spread in the neck, relevant in surgeries and diagnostics.