Scalp Anatomy Lecture Notes PDF

Scalp Prof Dr Mohamed El-Badry Mohamed Head of Human Anatomy and Embryology Department (Formerly) Faculty Of Medicine, Assiut University  THE SCALP CONSISTS OF: 5 layers forming the word SCALP: 1) Skin 2) Connective tissu...

Scalp Prof Dr Mohamed El-Badry Mohamed Head of Human Anatomy and Embryology Department (Formerly) Faculty Of Medicine, Assiut University  THE SCALP CONSISTS OF: 5 layers forming the word SCALP: 1) Skin 2) Connective tissue 3) Aponeurosis (epicranial) 4) Loose areolar tissue 5) Pericraneum 1. SKIN: Thick and hair-bearing Contains many sebaceous glands ……..(sebaceous cysts) 2. CONNECTIVE TISSUE: Beneath the skin Fibrofatty, fibrous septa uniting skin to underlying aponeurosis of occipitofrontalis Has numerous arteries and veins The arteries: Branches of external and internal carotid arteries and have free anastomosis between them 3. EPICRANIAL APONEUROSIS: Thin tendinous sheet Unites occipital and frontal bellies of occipitofrontalis muscle Its lateral margins: Attached to temporal fascia Subaponeurotic space: Potential space beneath the aponeurosis Limited in front and behind by origins of occipitofrontalis Extends laterally as far as attachment of the aponeurosis to temporal fascia 4. LOOSE AREOLAR TISSUE: Occupies the subaponeurotic space Loosely connects epicranial aponeurosis to periosteum of the skull Contains few small arteries and some important emissary veins Emissary veins: Valveless and connect superficial veins of the scalp with diploic veins of the skull bones and with intracranial venous sinuses Direction of blood: According to venous pressure outside and inside the skull Give passage to infection (Dangerous area of the scalp) 5. PERICRANIUM: Periosteum covering outer surface of the skull bones Continuous with endosteum on inner surface of the skull bones Note: First 3 layers of the scalp are bound together and move as a unit  OCCIPITOFRONTALIS MUSCLES Origin: 4 bellies (2 occipital and 2 frontal) Connected by an aponeurosis(insertion) Each occipital belly: Highest nuchal line on occipital bone Each frontal belly: Skin and superficial fascia of the eyebrow Insertion: Aponeurosis Nerve supply: Occipital belly: Posterior auricular branch of facial nerve Frontal belly: Temporal branch of facial nerve Action: Move the first 3 layers of the scalp forward or backward Loose areolar tissue: Allows aponeurosis to move on pericranium Frontal bellies: Raise eyebrows in surprise or horror  SENSORY NERVE SUPPLY OF THE SCALP 1) Supratrochlear nerve 2) Supraorbital nerve 3) Zygomaticotemporal nerve 4) Auriculotemporal nerve 5) Lesser occipital nerve 6) Greater occipital nerve SENSORY NERVE SUPPLY OF SCALP 1) SUPRATROCHLEAR NERVE:  Branch of ophthalmic division of trigeminal nerve  Passes backward close to median plane  Reaches vertex of the skull 2) SUPRAORBITAL NERVE:  Branch of ophthalmic division of trigeminal nerve  Supplies: Scalp as far backward as vertex 3) ZYGOMATICOTEMPORAL NERVE:  Branch of maxillary division of trigeminal nerve  Supplies: Scalp over the temple 4) AURICULOTEMPORAL NERVE: Branch of mandibular division of trigeminal nerve Ascends over side of the head from in front of auricle Its terminal branches supply skin over temporal region 5) LESSER OCCIPITAL NERVE: Branch of cervical plexus (C2) and supplies: Scalp over lateral part of occipital region Skin over medial side of the auricle 6) GREATER OCCIPITAL NERVE: Branch of: Posterior ramus of 2nd cervical nerve Ascends over back of the scalp Supplies: Skin as far as vertex of scalp  ARTERIAL SUPPLY OF THE SCALP 1) Supratrochlear artery 2) Supraorbital artery 3) Superficial temporal artery 4) Posterior auricular artery 5) Occipital artery  ARTERIAL SUPPLY OF THE SCALP 1) SUPRATROCHLEAR ARTERY: 2) SUPRAORBITAL ARTERY: Branches of: Ophthalmic artery Ascend in company with supratrochear and supraorbital nerves 3) SUPERFICIAL TEMPORAL ARTERY: Smaller terminal branch of: External carotid artery Ascends in front of auricle in company with auriculotemporal nerve 4) POSTERIOR AURICULAR ARTERY: Branch of: External carotid artery Ascends behind the auricle 5) OCCIPITAL ARTERY: Branch of: External carotid artery Ascends from apex of posterior triangle In company with greater occipital nerve Supplies: Skin over back of scalp as high as vertex of skull  VENOUS DRAINAGE OF THE SCALP 1) Supratrochlear vein 2) Supraorbital vein 3) Superficial temporal vein 4) Posterior auricular vein 5) Occipital vein  VENOUS DRAINAGE OF THE SCALP 1) SUPRATROCHLEAR VEIN: 2) SUPRAORBITAL VEIN: Unite at medial margin of the orbit to form facial vein 3) SUPERFICIAL TEMPORAL VEIN: Unites with maxillary vein in substance of parotid gland to form retromandibular vein 4) POSTERIOR AURICULAR VEIN: Unites with posterior division of retromandibular vein just below parotid gland to form: External jugular vein 5) OCCIPITAL VEIN: Drains into: Suboccipital venous plexus (lies beneath floor of upper part of posterior triangle) or into internal jugular vein Suboccipital venous plexus drains into: Vertebral veins LYMPH DRAINAGE OF THE SCLAP: Lymph vessels from: 1) Anterior part of scalp and forehead drain into: Submandibular nodes 2) Lateral part of scalp above ear drain into: Superficial parotid (preauricular) nodes 3) Part of scalp above and behind the ear drains into: Mastoid nodes 4) Back of scalp drains into: Occipital nodes THANK YOU