Human Anatomy: Scalp and Superficial Temporal Region

Which muscle inserts into the aponeurosis anteriorly?

What is the attachment point of the aponeurosis posteriorly?

What is the name of the first three layers of the scalp?

What is the function of the fourth layer of the scalp?

Where does the fourth layer of the scalp extend to?

What is the characteristic of the attachment of the pericranium to the bones?

What is the name of the deep fascia that covers the cranial vault?

What is the function of the occipitofrontalis muscle?

What is the origin of the frontal bellies of the occipitofrontalis muscle?

What is the nerve supply to the occipital bellies of the occipitofrontalis muscle?

What is the structure that the skin is adherent to through the dense superficial fascia?

What is the characteristic of the subcutaneous or superficial fascia in the centre of the head?

What is the boundary of the scalp anteriorly?

What is the characteristic of the skin of the scalp?

The soft tissues covering the cranial vault form the scalp
The scalp has anterior, posterior, and lateral boundaries:
- Anteriorly: supraorbital margins
- Posteriorly: external occipital protuberance and superior nuchal lines
- Laterally: superior temporal lines

The scalp consists of five layers:
- First three layers: surgical layers of the scalp, also known as scalp proper
- Fourth layer: loose areolar tissue
- Fifth layer: pericranium

Has two bellies: occipital (occipitalis) and frontal (frontalis)
Both bellies inserted into the epicranial aponeurosis
Occipital bellies: small, separate, and supplied by the posterior auricular branch of the facial nerve
Frontal bellies: longer, wider, and partly united in the median plane, supplied by the temporal branch of the facial nerve
Functions: raises the eyebrows and causes horizontal wrinkles in the skin of the forehead

Fourth layer (loose areolar tissue): extends into the eyelids, posteriorly to the highest and superior nuchal lines, and on each side to the superior temporal lines
Allows passage to emissary veins, which connect extracranial veins to intracranial venous sinuses
Fifth layer (pericranium): loosely attached to the surface of the bones, but firmly adherent to their sutures where the sutural ligaments bind the pericranium to the endocranium