Anatomy of head & neck Flashcards
Boundaries of Scalp
Ant. : superciliary arch
Post. : Superior nuchal line
on the sides: Superior temporal line
Layers of the scalp ( superficial to deep)
Skin
connective tissue (dense)
(Epicranial) Aponeurotic layer
Loose areolar tissue
Pericranium
What layers are attached firmly to each other?
The 1st 3 layers
What does the skin of the scalp contain?
1- numerous hair follicles
2- numerous sebaceous glands
What is the 2nd layer of the scalp formed of?
Dense fibrous connective tissue
What does the 2nd layer of the scalp contain?
1- Vessels and nerves of the scalp
2- Rich in fat and fibrous septa
Why does the scalp continue to bleed after a long time?
As the dense fibrous connective tissue holds the cut vessel open. Serotonin fails to vasoconstrict
Where does the epicranial aponeurosis attach to?
Ant. : Frontal bellies
Post. : Occipital bellies, Highest nuchal line, external occipital protuberence
On each side: Superior temporal line
Importance of Loose areolar connective tissue
Facilitate movements of epicranial aponeurosis
Where is the pericranium attached?
To its suture lines
Why is the infection of connective tissue layer limited?
Due to presence of fibrous septa
Why is the loose areolar tissue layer considered a dangerous zone?
As infection can pass into the cranial cavity via emissery vein
Origin & insertion of frontal belly of occipitofrontalis muscle? Give out its nerve supply
Arise: epicranial aponeurosis
inserted: skin of aye brow and root of nose
Nerve supply: temporal branch of facial nerve
Action of frontal belly of occipitofrontalis?
Raises the eyebrows
Origin & insertion of occipital belly of occipitofrontalis muscle? Give out its nerve supply
Arise: Lateral 2/3 of highest nuchal line
inserted: epicranial aponeurosis
Nerve supply: Posterior auricular branch of Facial nerve