SCALP
C
Extend
• from the superciliary arches anteriorly to the external occipital protuberance and
superior nuchal lines posteriorly
• Laterally it continues inferiorly to the zygomatic arch
■ S—skin
■ C—dense CT
SCALP PROPER
■ A—aponeurotic layer
■ L—loose connective tissue
■ P—pericranium
Skin
• hair
• Sweat
• sebaceous glands
Dense CT
• anchors the skin to the third layer
• contains the arteries, veins, and nerves supplying the scalp
• dense connective tissue surrounding the vessels tends to hold cut vessels open. This
results in profuse bleeding
Aponeurotic layer
• occipitofrontalis muscle has 2 bellies
• occipitofrontalis muscles move the scalp,
wrinkle the forehead, and raise the eyebrows
• aponeurotic tendon— epicranial
aponeurosis—connecting the two
FEATURE
FRONTAL BELLY
OCCIPITAL BELLY
ATTATCHMENT
skin of the eyebrows passes upward,
across the forehead, to become
continuous with the aponeurotic
tendon
lateral part of the superior nuchal line of
the occipital bone, passes superiorly to
attach to the aponeurotic tendon
INNERVATION
temporal branches of the facial nerve
posterior auricular branch of the facial
nerve
Loose connective tissue
• facilitates movement of the scalp proper over the calvaria
• Emissary veins: connect extracranial veins to intracranial sinuses
• DANGER AREA:
• Because of its consistency, infections tend to localize and spread through the loose
connective tissue
• Hemorrhage can occur
• Separation can occur
Pericranium
• periosteum on the outer surface of the calvaria
• attached to the bones of the calvaria but is removable, except in the area of the sutures.
Innervation
• Anterior to the ears and the vertex Branches of the trigeminal nerve [V]
• Posterior to the ears and the vertex branches from spinal cord levels C2 and C3
Arteries
• branches of either the external carotid artery or the ophthalmic artery, which is a
branch of the internal carotid artery
Clinicals
• Sebaceous cyst may develop in skin
• Laceration causes profuse bleeding as arteries are held open by dense CT
• Dangerous area (loose CT) because of emissary veins
• Blood collected causes black eye