Scalp

Question 1

the scalp extends from

Answer 1

the superciliary arches anteriorly to the external occipital protuberance and superior nuchal lines posteriorly

Question 2

laterally the scalp continues inferiorly to the

Answer 2

zygomatic arch

Question 3

what are the 5 layers of the scalp

Answer 3

• skin
• dense subcutaneous tissue (connective tissue)
• epicranial aponeurosis
• loose areolar connective tissue
• periosteum

Question 4

what are the boundaries of the scalp

Answer 4

anteriorly-eyebrows

laterally- ears/ zygomatic arches

posteriorly- superior nuchal lie

Question 5

what part is torn during scalp accidents

Answer 5

skin
connective tissue
aponeurosis

Question 6

what are the layers of the scalp like

Answer 6

skin- is thick, has may sebaceous glands and is hair bearing

connective tissue- is fibrofatty and the has the fibrous septa uniting the skin to the underlying aponeurosis of the occipitofrontalis muscle.
numerous arteries and veins are found i this layer ( the arteries are branches of the external and internal carotid arteries where then free anastomosis takes place between them)

aponeurosis- is a thin tendinous seet that unites the occipital and frontal bellies of the occipitofrontalis muscle.
The lateral margins of the aponeurosis are attached to temporal fascia

loose areolar tissue- occupies the subaponeurotic space and loosely connects the epicranial aponeurosis to the periosteum of the skull.
it contains a few small arteries and some emissary veins
pericranium- is the periosteum covering the outer surface of the bones

Question 7

why is the loose areolar tissue called the dangerous layer of scalp

Answer 7

because emissary veins open here and carry any infection inside the brain through intracranial sinuses(venous sinus)

bleeding here can lead to black eye

Question 8

what the muscle of the scalp called

Answer 8

occipitofrontalis muscle

Question 9

describe the occipitofrontalis muscle

Answer 9

it has a frontal belly anteriorly
has an occipital belly posteriorly
has an epicranial aponeurosis connecting the 2

Question 10

whats the origin of the occipital belly of occipitofrontalis

whats the origin of the frontal belly of occipitofrontalis

Answer 10

highest nuchal line of occipital bone

skin and superficial fascia of eyebrow

Question 11

whats the insertion of the occipitofrontalis muscle

Answer 11

epicranial aponeurosis

Question 12

whats the nerve supply of the occipitofrontalis

Answer 12

facial nerve

Question 13

whats the action of the occipitofrontalis muscle

Answer 13

moves scalp on skull and raises eyebrows

Question 14

what are the 3 layers of the calvaria (skull cap)

Answer 14

outer table
diploe
inner table

Question 15

what are emissary veins

Answer 15

are valveless veins which connect the superficial veins of the scalp with the diploic veins of the skull bones and intracranial venous sinuses (dural sinuses)

Question 16

what do diploic veins do

Answer 16

drain blood from the space within the bone of the skull into the dural sinuses

Question 17

diploic veins course in

Answer 17

diploe

Question 18

diploe veins connect to

Answer 18

cranial cavity and surface of skull

Question 19

diploic veins can transmit what

Answer 19

infection from scalp to brain via emissary veins

Question 20

what things are associated with the scalp clinically

Answer 20

infection can spread from loose areolar connective tissue via emissary veins to meninges and cause meningitis

hematoma

Question 21

whats the nerve supply of the scalp in front of the auricle

Answer 21

there are 4 sensory nerves all from the trigeminal nerve i.e.

• supra trochlear N
• supra orbital N
• zygomatico temporal n
• auriculo temporal N

and 1 motor nerve i.e. temporal branch of facial N

Question 22

whats the nerve supply of the scalp behind the auricle

Answer 22

there are 4 sensory nerves from the the cervical Ns i.e.

• great auricular N
• lesser occipital N
• greater occipital N
• 3rd occipital nerve

and 1 motor nerve i.e. the posterior auricular branch of the facial N

Question 23

whats the arterial supply of the scalp

Answer 23

there are 5 arteries on each side i.e. 
3 in front of auricle
-supratrochlear
-supraorbital
-superficial temporal

2 behind auricle

• posterior auricular
• occipital

Question 24

what are some scalp injuries

Answer 24

avulsion- tearing away of scalp

the scalp can be infected with maggots