Scalp (dave's notes) Flashcards
What is notable about the skin of the scalp?
It is the thickest in the body; 3-7mm thick, and most thick over the occiput. There is a high concentration of sebaceous glands.
Where are blood vessels in the scalp found?
The connective tissue layer.
How is the scalp attached to the skull?
Tissue of the fourth layer is very loose, enabling movement over the pericranium. The pericranium is only loosely attached to the bone but firmly adherent to eh sutures
Describe the structure of occipitofrontalis. From whence does it originate and insert?
Occipitalis and frontalis with a central epicranial aponeurosis.
Occipitalis arises from the highest nuchal line and passes forwards. Frontalis arises from the front of the aponeurosis and attaches to orbicularis oculi.
The two frontalis muscles join in the midline.
What is the nerve supply to occiptofrontalis?
The facial nerve; posterior auricular branch to occipitalis and temporal/zygomatic branches to frontalis
What is the action of occipitalis and frontalis?
Occipitalis tends to anchor the aponeurosis while frontalis elevates the eyebrows.
How may bleeding track to the eye?
Beneath the aponeurosis is a plane where bleeding can track down to the eye. This is also the plane where scalping occurs.
What is the blood supply to the scalp?
From the external carotid artery by occipital, posterior auricular and superficial temporal arteries, and by the internal carotid artery via the supratrochlear and supraorbital branches
Free anastomoses
What are arteries in the scalp attached to? What is the clinical significance of this?
They are attached to the deepest layer of the dermis and in scalp wounds they are held open.
Where does lymph from the scalp drain?
To nodes outside the scalp; occipital and posterior auricular and submandibular nodes, eventually to reach the deep cervical chain
What is the nerve supply to the scalp?
Mainly via sensory nerves running with the arteries
What is the nerve supply to the posterior aspect of the scalp? What are the boundaries of this?
The greater occipital and third occipital nerves extend to the vertex, and the lesser occipital supplies the skin behind the ear
What is the nerve supply to the region of the temple?
Auriculotemporal and zygomaticotemporal nerves
What is the nerve supply to the forehead and front of the scalp?
Supratrochlear and supraorbital nerves.
