The Investing layer of deep cervical fascia is the most superficial part of the deep cervical fascia, and it encloses the whole neck.
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
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
It is considered by some sources to be incomplete or nonexistent.
