2nd LQ - muscles of the head and related structures

Question 1

layers of scalp:

Answer 1

skin
connective tissue (subcutaneous tissue)
aponeurosis (epicranial)
Loose areolar tissue
Pericranium

Question 2

thick and hair bearing
and contains numerous sebaceous
glands.

Answer 2

Skin

Question 3

beneath the skin.

a dense fibrofatty layer
containing fibrous septa that unite the skin to the underlying epicranial
aponeurosis.

contains numerous blood vessels.

The arteries are derived from both the external and internal carotid arteries, and free anastomoses occur between them.

Answer 3

connective tissue (subcutaneous tissue)

Question 4

thin, tendinous sheet that unites the
occipital and frontal bellies of the
occipitofrontalis muscle

The lateral margins of
the aponeurosis are attached to the
temporal fascia.

Answer 4

Aponeurosis

Question 5

Potential space

This occupies the subaponeurotic space and loosely connects the
epicranial aponeurosis to the periosteum of the to skull (the pericranium)

Answer 5

Loose areolar tissue

Question 6

Periosteum of skull bones

Answer 6

Pericranium

Question 7

why the 4th layer is the
“dangerous layer of the scalp.”

Answer 7

Emissary veins
Valveless
Pus can flow into the skull

• supratrochlear and the supraorbital arteries
• superficial temporal artery
• posterior auricular artery
• occipital artery

Question 8

why a clean wound in the scalp heals promptly

Answer 8

Numerous Blood supply - scalp is highly vascular, meaning it has an extensive network of blood vessels

Rapid Cell Turnover - Skin cells are constantly being produced, and this turnover rate facilitates the repair of damaged tissue.

Minimal Contaminants: A clean wound in the scalp typically results from a cut or incision with a sharp object, such as a surgical scalpel or a clean-edged object. These types of wounds are less likely to introduce foreign contaminants, such as dirt or bacteria

Efficient Immune Response:
Minimal Tension
Adequate Nutrition
Regenerative Capacity
Careful Closure

Question 9

why an incised wound involving the first 3 layers of the scalp gapes if it is along coronal plane

Answer 9

• tension of the epicranial aponeurosis
• the 1st 3 layers are intimately bounded together and move as a unit

Direction of the Wound: The coronal plane typically divides the body into front and back portions. When a wound occurs along this plane in the scalp, the force or injury is often applied in a direction perpendicular to the natural orientation of the scalp’s skin and tissue layers. This perpendicular force can cause the wound edges to separate more easily.

Question 10

A wound involving only the first 2 layers bleeds profusely and is not easily controlled

Answer 10

numerous arteries (branches of the ICA and ECA) and veins which ramify

arterial walls are attached to the septa in the subcutaneous tissue and are unable to contract or retract to allow blood clotting

Question 11

Bleeding in the 4th layer is diffuse and gravitates to the face:

Answer 11

blood or pus beneath the epicranial aponeurosis spreads over the CALVARIA being limited in front by the orbital margin, behind by nuchal lines and laterally by the temporal lines

Question 12

loosely connects the epicranial aponeurosis to the periosteum of skull (pericranium)

Answer 12

subaponeurotic space

Question 13

Bleeding under the 5th
layer is confined to particular cranial bones

Answer 13

Subperiosteal blood or pus is
limited to one bone due to
attachment of the periosteum
to sutural ligaments

Question 14

dangerous area is drained by facial vein.

spread of infection via inferior ophthalmic veins to cavernus sinus and cause thrombosis which can lead to

Answer 14

cerebral edema