Scalp : layers, muscles, vessels, and
innervations of the scalp
• The skin of the scalp continues from the front and
lateral side of the face into the occipital region of
the skull posteriorly.
• The scalp is made of 5 layers and they spell scalp:
• S -- Skin
• C -- Connective tissue (Dense)
• A -- Aponeuroses
• L -- Loose connective tissue
• P -- Periosteum-Pericranium
Major Sutures and Anthropological
Landmarks of the Skull
The major sutures to
identify are the:
• Coronal
• Lambdoid
• Sagittal
Major anthropological
points:
• Bregma
• Lambda
• The motor nerves to the muscles of facial
expression and the muscles themselves are just
beneath the skin. Usually muscles have 2 bony
attachments (Insertion & Origin). The muscles of
the face may have a bony attachment but the
insertion is into the skin.
• This is how we can make facial expressions of
happiness, sadness, anger.
• Once skin is removed, the muscles are identified
Muscles of facial expression
1. Frontalis
2. Orbicularis oculi:
• Orbital portion
• Palpebral portion
3. Zygomaticus major
4. Levator labii superioris alequae nasii
5. Levator anguli oris
6. Orbicularis oris
7. Risorius
8. Depressor anguli oris
9. Depressor labii inferioris
10.Mentalis
11.Platysma
Image displays the Buccinator and
the Masseter muscles. The
Masseter is a muscle of
mastication, not facial expression
but it is superficial in the face.
Muscles around the mouth include:
•
Zygomaticus major (3)
•
Levator labii superior alequae nasii (4)
•
Levator anguli oris (5)
•
Orbicularis oris (6)
•
Risorius (7)
•
Depressor anguli oris (8)
•
Depressor labii inferioris (9)
•
Buccinator
Muscles around the orbit are:
•
Frontalis (1)
•
Orbicularis oculi (2)
MOTOR INNERVATION TO THE FACE
The motor innervation to the
muscles of facial expression is
Cranial Nerve VII (Facial) (green
in the diagram).
It leaves the skull through the
stylomastoid foramen on the base
of the skull and immediately turns
forward to enter the substance of
the parotid gland (pink in the
image). While within the gland, it
divides into 5 major divisions:
•
T -- temporal
•
Z -- zygomatic
•
B -- buccal
•
M -- mandibular
•
C -- cervical