Nerve Supply of the Scalp

Nerve Supply of the Scalp

• The zygomaticotemporal nerve from the maxillary supplies the scalp over the temple.
• The auriculotemporal nerve from the mandibular supplies the skin over the temple.
• The great auricular nerve from the cervical plexus (C2 and C3) supplies a small area of the scalp just posterior to the ear.
• The lesser occipital nerve from the cervical plexus (C2) supplies the scalp over the lateral occipital region and the medial surface of the auricle.
• The great occipital nerve is a branch of the posterior ramus of the C2 spinal nerve, supplying a large part of the posterior scalp as far superiorly as the vertex.
• The third occipital nerve is a branch of the posterior ramus of the C3 spinal nerve, supplying a small area of the lower part of the scalp.

Blood Supply

Arterial Supply of the Scalp

• Supratrochlear artery from ophthalmic of ICA.
• Supraorbital artery, one of two terminal branches of ECA.
• Superficial temporal artery.
• Posterior auricular artery from ECA.
• Occipital artery.

Venous Drainage

• The supratrochlear and supraorbital veins → the anterior facial vein.
• The superficial temporal vein and the maxillary vein → the retromandibular vein.

Layers of the Scalp

• Skin: thick and hairy, contains numerous sebaceous glands.
• Connective tissue (fibrofatty layer): contains many nerves, arteries, and veins.
• Aponeurosis (occipitofrontalis): a thin tendinous sheet of deep fascia, unites the occipital and frontal bellies of the occipitofrontalis muscle.
• Loose areolar tissue: loosely connects the aponeurosis to the pericranium, contains a few small arteries and emissary veins.
• Pericranium: periosteum covering the outer surface of the skull bones, becomes continuous with the endostium on the inner surface of the skull bones through sutures.

Muscles

• Occipito-frontalis muscle:
  • Origin: occipital belly from the highest nuchal line, frontal belly from the skin and superficial fascia of the eyebrows.
  • Insertion: both bellies are inserted into the epicranial aponeurosis.
  • Nerve supply: occipital belly → posterior auricular of facial, frontal belly → temporal of facial.
  • Action: moves the superficial 3 layers together, raises the eyebrows, and frowns.