Investing layer of deep cervical fascia explained

Investing layer of deep cervical fascia
Latin:	lamina superficialis fasciae cervicalis

The investing layer of deep cervical fascia is the most superficial part of the deep cervical fascia, and encloses the whole neck.

It is considered by some sources to be incomplete^[1] or nonexistent.^[2]

Attachments

It surrounds the neck like a collar, it splits around the sternocleidomastoid muscle and the trapezius muscle. It is attached as;

• Posteriorly - Ligamentum nuchae
• Anteriorly - Attached to the hyoid bone
• Superiorly - (from backwards to forwards);
  • External occipital protuberance and superior nuchal line of occipital bone
  • Mastoid process of temporal bone
  • External acoustic meatus
  • Lower margin of the zygomatic arch
  • Lower border of body of mandible from the angle of mandible to the symphysis menti
• Inferiorly - (from backwards to forwards);
  • Spine and acromial process of scapula
  • Upper surface of the clavicle
  • Suprasternal notch of manubrium sterni^[3]

Tracings

• Horizontal extent - From ligamentum nuchae when traced forward, the fascia splits and encloses trapezius, reunites and form roof of posterior triangle of neck; again splits and encloses sternocleidomastoid, reunites and forms the roof of anterior triangle.
• Vertical extent -
  • Superior tracing - It splits and encloses submandibular gland and parotid gland;

- It splits at lower border of submandibular gland into superficial and deep layers;which attach to lower body of body of mandible and mylohyoid line of mandible - It splits at lower pole of parotid gland into superficial and deep layers; superficial layer attaches to zygomatic arch and forms parotido-masseteric fascia after blending with masseter, deep layer attaches to tympanic plate and styloid process forming the stylomandibular ligament

• • Inferior tracing - The fascia splits to enclose two spaces; suprasternal space and supraclavicular space^[4]

External links

• Sagittal Section Showing Deep Cervical Fascial Layers
• Infrahyoid Cross-Section Showing Layers of Deep Cervical Fascia
• Suprahyoid Cross-Section Showing Layers of Deep Cervical Fascia

Notes and References

1. Zhang M, Lee AS . 2002 . The investing layer of the deep cervical fascia does not exist between the sternocleidomastoid and trapezius muscles . Otolaryngol Head Neck Surg . 127 . 5 . 452–4 . 10.1067/mhn.2002.129823 . 12447241 . 19627402.
2. Nash L, Nicholson HD, Zhang M . 2005 . Does the investing layer of the deep cervical fascia exist? . Anesthesiology . 103 . 5 . 962–8 . 10.1097/00000542-200511000-00010 . 16249670 . 20959436. free .
3. Book: Dutta, Asim Kumar. Essentials of Human Anatomy Head & Neck. 2013. Current books international. kolkata. 978-81-86793-79-4. 126.
4. Book: Dutta, Asim Kumar. Essentials of Human Anatomy Head & Neck. 2013. Current books international. kolkata. 978-81-86793-79-4. 126–128.