Anatomy Of The Scalp Flashcards
What is known as the danger area of the scalp?
Loose connective tissue
Pus and blood spread easily within it and can pass into the cranial cavity along the emissary veins, potentially leading to meningitis.
What can occur if an infection spreads from the scalp to the meninges?
Meningitis
What are the two divisions of the occipitofrontalis muscle?
Front belly and occipital belly
What is the origin of the occipital belly of the occipitofrontalis?
Lateral two-thirds of superior nuchal line
What is the insertion point of the occipital belly of the occipitofrontalis?
Epicranial aponeurosis
What action does the occipital belly perform?
Retracts scalp; increases effectiveness of frontal belly
What is the outer layer of the skull called?
Periosteum
How is the periosteum attached to the bone?
Loosely attached and easily stripped by a subperiosteal haematoma
What does the loose areolar connective tissue allow?
Free movement of the first three layers of the scalp over the underlying calvaria
What is the epicranial aponeurosis also known as?
Galea aponeurotica
What does the epicranial aponeurosis connect?
Occipitalis and frontalis muscles
What is the layer that connects the skin to the epicranial aponeurosis?
Dense connective tissue
What are the main arteries that supply the scalp?
- Superficial temporal artery
- Posterior auricular artery
- Occipital artery
- Supraorbital artery
- Supratrochlear artery
What are the superficial veins involved in the venous drainage of the scalp?
- Superficial temporal veins
- Occipital vein
- Posterior auricular vein
- Supraorbital vein
- Supratrochlear vein
What can cause a black eye related to scalp anatomy?
Bleeding beneath the epicranial aponeurosis tracking down through the space
Why do deep lacerations to the scalp tend to bleed profusely?
- Pull of occipitofrontalis prevents closure of bleeding vessel
- Blood vessels adhered to dense connective tissue prevent vasoconstriction
- Numerous anastomoses contribute to profuse bleeding
What are the major nerves that innervate the scalp?
- Supratrochlear nerve
- Supraorbital nerve
- Zygomaticotemporal nerve
- Auriculotemporal nerve
What is the thickest skin in the body and where is it located?
Skin of the scalp, thickest in the occipital region
What are the five layers of the scalp from superficial to deep?
- Skin
- Dense connective tissue
- Epicranial aponeurosis
- Loose areolar connective tissue
- Periosteum (Pericranium)
Which cervical nerve supplies the skin posterior to the ear?
Lesser occipital nerve
What is the extent of the scalp anteriorly?
Supra-orbital margins of frontal bone
What is the extent of the scalp posteriorly?
Superior nuchal lines of occipital bone
True or False: The scalp has a good venous and lymphatic drainage.
True
