Muscle
Platysma
Thin sheet moving the superficial neck tissues
High-yield
Despite its neck location, platysma belongs to the facial-expression muscles and receives CN VII, chiefly through its cervical branch.
Overview
Platysma lies just beneath the skin of the front and sides of the neck. Its fibers run from the upper chest toward the mandible and lower face. It tensions the neck skin and contributes to downward movements of the lower facial tissues.
Reference facts
- Origin
- Superficial fascia over pectoralis major and deltoid
- Insertion
- Mandibular border and soft tissues of the lower face and mouth angle
- Action
- Tightens the neck skin and assists downward movement of the lower lip, mouth angle and mandible
- Innervation
- Predominantly the cervical branch of the facial nerve (CN VII)
- Blood supply
- Submental and other facial branches, with additional cervical arterial contributions
Clinical correlation
The cervical and marginal mandibular facial nerve branches pass near the upper platysma. Injury in this region can affect neck contraction or lower-lip movement, depending on the branch involved.
Frequently asked questions
What does the platysma do?
The platysma tightens the neck skin and assists downward movement of the lower lip, mouth angle and mandible.
What nerve innervates the platysma?
Predominantly the cervical branch of the facial nerve (CN VII).
Where does the platysma attach?
Origin: Superficial fascia over pectoralis major and deltoid. Insertion: Mandibular border and soft tissues of the lower face and mouth angle.
What is the blood supply of the platysma?
The platysma is supplied by the submental and other facial branches, with additional cervical arterial contributions.