Scalp 555225 219901783 2008-06-17T11:20:51Z 212.9.28.9 {{for|other uses of the word}} {{Infobox Anatomy | Name = {{PAGENAME}} | Latin = | GraySubject = 105 | GrayPage = 378 | Image = Double_cowlick.jpg | Caption = | Image2 = | Caption2 = | Precursor = | System = | Artery = [[supratrochlear artery|supratrochlear]], [[supraorbital artery|supraorbital]], [[superficial temporal artery|superficial temporal]], [[occipital artery|occipital]] | Vein = [[superficial temporal vein|superficial temporal]], [[posterior auricular vein|posterior auricular]], [[occipital vein|occipital]] | Nerve = [[supratrochlear nerve|supratrochlear]], [[supraorbital nerve|supraorbital]], [[greater occipital nerve|greater occipital]], [[lesser occipital nerve|lesser occipital]] | Lymph = [[occipital lymph nodes|occipital]], [[mastoid lymph nodes|mastoid]] | MeshName = Scalp | MeshNumber = A01.456.810 | DorlandsPre = s_03 | DorlandsSuf = 12721502 | }} The '''scalp''' is the anatomical area bordered by the [[face]] anteriorly and the [[neck]] to the sides and posteriorly. ==Layers== It is usually described as having five layers, which can be remembered with the [[mnemonic]] "SCALP":<ref>{{MedicalMnemonics|258|||}}</ref> * S: The [[skin]] on the head from which [[head hair]] grows. It is richly supplied with [[blood]] vessels. * C: [[Connective tissue]]. a thin layer of [[fat]] and fibrous tissue lies beneath the skin * A: The aponeurosis (or [[galea aponeurotica]]) is the next layer. It is a tough layer of dense fibrous tissue which runs from the [[frontalis muscle]] anteriorly to the [[occipitalis]] posteriorly * L: The [[loose areolar connective tissue]] layer provides an easy plane of separation between the upper three layers and the pericranium. In [[scalping]] the scalp is torn off through this layer. It also provides a plane of access in [[craniofacial surgery]] and [[neurosurgery]]. This layer is sometimes referred to as the "[[Danger Zone]]" because of the ease by which infectious agents can spread through it to [[emissary veins]] which then drain into the [[cranium]]. The loose areolar tissue in this layer is made up of random [[collagen I]] bundles, [[collagen III]] and is highly vascular and cellular. It will also be rich in [[glycosaminoglycans]] (GAGs) and will be constituted of more matrix than fibers. * P: The pericranium is the [[periosteum]] of the skull bones and provides nutrition to the bone and the capacity for repair. It may be lifted from the bone to allow removal of bone windows ([[craniotomy]]). 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; this requires suturing. This can be achieved with simple or vertical matress sutures using a non-absorbable material, which are subsequently removed at around day 7. Remember thorough wound irrigation and tetanus care for dirty wounds. ==Blood supply== The blood supply of the scalp is via five pairs of arteries, three from the [[external carotid]] and two from the [[internal carotid]]: * internal carotid ** the [[supratrochlear artery]] to the midline forehead. supratrochlear artery is a branch of ophthalmic branch of the internal carotid artery. ** the [[supraorbital artery]] to the lateral forehead and scalp as far up as the vertex. supraorbital artery is a branch of ophthalmic branch of the internal carotid artery. * external carotid ** the [[superficial temporal artery]] which gives frontal and parietal branches to supply much of the scalp ** the [[occipital artery]] which runs from posteriorly to supply much of the back of the scalp. ** the [[posterior auricular artery]] , a branch of the external carotid artery , ascends behind the auricle to supply the scalp above and behind the auricle. ==Innervation== The scalp is innervated by the following:<ref>{{MedicalMnemonics|2046|||}}</ref> * [[Supratrochlear nerve]] and the [[supraorbital nerve]] from the [[ophthalmic division]] of the [[trigeminal nerve]] * [[Greater occipital nerve]] (C2) posteriorly up to the vertex * [[Lesser occipital nerve]] (C3) behind the ear. * [[Zygomaticotemporal nerve]] from the [[maxillary nerve|maxillary division]] of the [[trigeminal nerve]] supplying the hairless temple * [[Auriculotemporal nerve]] from the [[mandibular division]] of the [[trigeminal nerve]] There are no lymph nodes in the scalp; lymphatic drainage is to the pre- and post-auricular nodes. ==Role in aesthetics== The scalp plays an important role in the [[aesthetics]] of the face. [[Androgenic alopecia]], or male pattern hair loss, is a common cause of concern to men. It may be treated by medication (eg [[finasteride]]) or [[hair transplantation]] with variable success. If the scalp is heavy and loose, a common change with [[aging]], the forehead may be low, heave and deeply lined. The [[brow lift]] procedure aims to address these concerns. ==Pathology== The scalp is a common site for the development of tumours including: * [[epidermoid cyst]] * pilar cyst * [[actinic keratosis]] and [[squamous cell carcinoma]] * [[basal cell carcinoma]] * [[merkel cell]] tumours ==Scalp conditions== * [[Dandruff]] -- A common problem due to the excessive shedding of dead skin cells from the scalp * [[Cutis verticis gyrata]] -- A descriptive term for a rare deformity of the scalp. * [[Head lice]] ==See also== * [[Trichology]] -- the scientific study of hair and scalp * [[Trichodynia]] -- burning scalp syndrome * [[Scalping]] -- the act of removing the scalp, usually with the hair, as a portable proof or trophy of prowess in war. ==Additional images== <gallery> Image:Gray1196.png|Diagrammatic section of scalp. </gallery> ==References== <references/> {{Head and neck general}} ==External links== * {{BUHistology|08601ooa}} - "Integument: scalp, transverse" * {{BUHistology|08801ooa}} - "Integument: scalp" * {{NormanAnatomy|lesson1}} * http://www.dartmouth.edu/~humananatomy/figures/chapter_47/47-1.HTM [[category:Head and neck]] [[de:Kopfschwarte]] [[es:Cuero cabelludo]] [[eo:Skalpo]] [[fr:Cuir chevelu]] [[ko:머릿가죽]] [[it:Cuoio capelluto]] [[nl:Kruin]] [[pt:Couro cabeludo]] [[fi:Päänahka]] [[sv:Skalp]] [[tl:Anit]] [[zh:頭皮]]