Suprahyoid region - Platysma, anterior jugular vein, submental and submandibular nodes (dave's notes) Flashcards
What is the platysma part of?
The panniculus carnosus
What is the panniculus carnosus? What muscles are part of it?
The panniculus carnosus is a part of the subcutaneous tissues in the study of animal anatomy. It is a layer of striated muscle deep to the panniculus adiposis. In humans the platysma muscle of the neck, palmaris brevis in the hand, and the dartos muscle in the scrotum are described as a discrete muscle of the panniculus carnosus. Some of the muscles of facial expression in the head are part of the panniculus carnosus. In other parts of the body, the layer is vestigial, and may be absent or may exist only as microscopic, disconnected fibers.
What are the limits of the platysma?
The platysma extends from the deep fascia over pectorals major and the most anterior part of the deltoid to the lower border of the mandible
What vascular structures does the platysma cover?
The external and anterior jugular veins
What is the distribution of the muscle bellies of platysma?
The muscles are separated inferiorly but converge til they overlap below the chin
What is the nerve supply to platysma?
Cervical branch of the facial nerve
What is the action of platysma?
Facial expression, showing teeth, support for veins.
Where do the anterior jugular veins commence?
Just beneath the chin side by side beneath platysma
What do the anterior jugular veins pierce? In what region do they lie?
The anterior jugular veins pierce the deep fascia in the suprasternal region to lie in the suprasternal space
Where do the anterior jugular veins go after reaching the suprasternal space?
The pass laterally beneath SCM to enter the EJV
How many submental lymph nodes are there? Which layer are they found in?
3-4 submental nodes. Found superficial and deep to the investing layer.
What area do the submental nodes drain?
They drain across the midline a wedge of tissue at the floor of the mouth, then pass to submandibular nodes.
How many submandibular nodes are there? Where are they found?
Approx 6. Found on the surface of the submandibular gland.
What do the submandibular glands drain?
The submental nodes Lateral lower lips Upper lip External nose Anterior tongue Anterior half of the nasal walls The paranasal sinuses All of the teeth
