Scalp

1. SCALP BY DR UZMA NAJAM

2. Consists of five layers S : Skin C : Connective tissue A : Aponeurosis L : Loose areolar connective tissue P : Pericranium

3. SKIN Thick & hair-bearing and contains numerous sebaceous glands

4. CONNECTIVE TISSUE The superficial fascia is a fibro fatty layer Connects skin to the underlying aponeurosis of the occipitofrontalis muscle Provides a passageway for nerves and blood vessels. CLINICAL IMPORTANCE: If the vessels are cut, this attachment prevents vasospasm, which could lead to profuse bleeding after injury.

5. APONEUROSIS A thin, tendinous sheet that unites the occipital and frontal bellies of the OCCIPITOFRONTALIS muscle. Lateral margins are attached to the temporal fascia. the sub-aponeurotic space is the potential space beneath the epicranial aponeurosis

6. CLINICAL IMPORTANCE The clinically important layer is the aponeurosis. Scalp lacerations through this layer mean that the "anchoring" of the superficial layers is lost and gaping of the wound occurs and this requires suturing.

7. LOOSE AREOLAR TISSUE Loosely connects the epicranial aponeurosis to the pericranium & allows the superficial 3 layers of the scalp to move over the pericranium. Contains Emissary veins which connects the superficial scalp veins to the Diploic veins of skull and with intracranial venous sinuses.

8. PERICRANIUM is the periosteum covering the outer surface of skull bones. at the sutures between individual skull bones, the pericranium become continuous with periosteum (endosteum) on the inner surface of skull bones.

9. MUSCLES OF SCALP OCCIPITOFRONTALIS: consists of four bellies two Occipital & two Frontal connected by an aponeurosis. the Occipital belly is supplied by Posterior Auricular branch & Frontal belly is supplied by temporal branch of facial nerve. ACTION: The loose areolar tissue (4 th layer) allowing the aponeurosis to move on the pericranium. frontal bellies can raise the eyebrows in expression of surprise or horror.

10. SENSORY NERVE SUPPLY Six sensory nerve branches of either the trigeminal nerve or the cervical nerve supply the scalp. Can be remembered by Z-GLASS ” Z ygomaticotemporal nerve   G reater occipital nerve   L esser occipital nerve   A uriculotemporal nerve S upratrochlear nerve   S upraorbital nerve

11. The SUPRATROCHLEAR NERVE , branch of the ophthalmic division of the trigeminal nerve & supplies the medial plane at the frontal region up to the vertex. The SUPRAORBITAL NERVE , a branch of the ophthalmic division of the trigeminal nerve supplies the scalp at the front, lateral to the supratrochlear nerve distribution up to the vertex. The ZYGOMATICOTEMPORAL NERVE , branch of the maxillary division of the trigeminal nerve supplies the hairless temple . The AURICULOTEMPORAL NERVE , branch of the mandibular division of the trigeminal nerve supplies the skin over the temporal region of the scalp. The LESSER OCCIPITAL NERVE , branch of the cervical plexus (C2), supplies behind ear. The GREATER OCCIPITAL NERVE , branch of the posterior ramus of the second cervical nerve & supplies posteriorly upto the vertex.

12. ARTERIAL SUPPLY OF SCALP SUPRATROCHLEAR & SUPRAORBITAL ARTERIES SUPERFICIAL TEMPORAL ARTERY POSTERIOR AURICULAR ARTERY OCCIPITAL ARTERY

13. Venous Drainage The veins of the scalp accompany the arteries and have similar names. The Supratrochlear & Supraorbital Veins Superficial Temporal Vein The Posterior Auricular Vein Occipital Vein

14. LYMPHATIC DRAINAGE Anterior part of scalp & forehead drains into submandibular lymph nodes. Lateral part of scalp drains into superficial parotid lymph nodes. Lymph vessels above & behind the ear drain into mastoid lymph nodes Vessels in back drain into occipital lymph nodes.