The scalp is the anatomical area bordered by the face

Face

The face is a central sense organ complex, for those animals that have one, normally on the ventral surface of the head, and can, depending on the definition in the human case, include the hair, forehead, eyebrow, eyelashes, eyes, nose, ears, cheeks, mouth, lips, philtrum, temple, teeth, skin, and...

 anteriorly and the neck

Neck

The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...

 to the sides and posteriorly.

Layers

It is usually described as having five layers, which can conveniently be remembered as a mnemonic

Mnemonic

A mnemonic , or mnemonic device, is any learning technique that aids memory. To improve long term memory, mnemonic systems are used to make memorization easier. Commonly encountered mnemonics are often verbal, such as a very short poem or a special word used to help a person remember something,...

:

• S: The skin
  Skin
  -Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...
  
   on the head from which head hair grows. It contains numerous sabaeceous glands and hair follicles
• C: Connective tissue
  Connective tissue
  "Connective tissue" is a fibrous tissue. It is one of the four traditional classes of tissues . Connective Tissue is found throughout the body.In fact the whole framework of the skeleton and the different specialized connective tissues from the crown of the head to the toes determine the form of...
  
  . A thin layer of fat
  Fat
  Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...
  
   and fibrous tissue lies beneath the skin.
• A: The aponeurosis called epicranial aponeurosis (or galea aponeurotica
  Galea aponeurotica
  The galea aponeurotica is a tough layer of dense fibrous tissue which covers the upper part of the cranium; behind, it is attached, in the interval between its union with the Occipitales, to the external occipital protuberance and highest nuchal lines of the occipital bone; in front, it forms a...
  
  ) is the next layer. It is a tough layer of dense fibrous tissue which runs from the frontalis muscle
  Frontalis muscle
  The Frontalis muscle , also known as the occipitofrontalis or epicranius, is thin, of a quadrilateral form, and intimately adherent to the superficial fascia. It is broader than the Occipitalis and its fibers are longer and paler in color...
  
   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
  Scalping
  Scalping is the act of removing another person's scalp or a portion of their scalp, either from a dead body or from a living person. The initial purpose of scalping was to provide a trophy of battle or portable proof of a combatant's prowess in war...
  
   the scalp is torn off through this layer. It also provides a plane of access in craniofacial surgery
  Craniofacial surgery
  Craniofacial surgery is a surgical subspecialty of maxillofacial surgery, plastic surgery, and ENT that deals with congenital and acquired deformities of the skull, face, and jaws. Although craniofacial treatment often involves manipulation of bone, craniofacial surgery is not tissue-specific,...
  
   and neurosurgery
  Neurosurgery
  Neurosurgery is the medical specialty concerned with the prevention, diagnosis, treatment, and rehabilitation of disorders which affect any portion of the nervous system including the brain, spine, spinal cord, peripheral nerves, and extra-cranial cerebrovascular system.-In the United States:In...
  
  . 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
  Emissary veins
  The emissary veins are valveless veins which normally drain external veins of the skull into the dural venous sinuses. However, because they are valveless, pus can flow into the skull through them as well, making them a possible route for transmission of extracranial infection to get into the...
  
   which then drain into the cranium. The loose areolar tissue in this layer is made up of random collagen I bundles, collagen III. It contains the major blood vessels of the scalp, which bleed profusely upon injury, partly due to the absence of venous valves found in the circulation below the neck. It will also be rich in glycosaminoglycans (GAGs) and will be constituted of more matrix than fibers.
• P: The pericranium is the periosteum
  Periosteum
  Periosteum is a membrane that lines the outer surface of all bones, except at the joints of long bones. Endosteum lines the inner surface of all bones....
  
   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
  Craniotomy
  A craniotomy is a surgical operation in which a bone flap is temporarily removed from the skull to access the brain. Craniotomies are often a critical operation performed on patients recording, brain imaging, and for neurological manipulations such as electrical stimulation and chemical...
  
  ).

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 mattress sutures using a non-absorbable material, which are subsequently removed at around days 7-10.

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
    Supratrochlear artery
    The supratrochlear artery , one of the terminal branches of the ophthalmic artery, branches off where the ophthalmic travels posterior to the trochlea.-Course:...
    
     to the midline forehead. The supratrochlear artery is a branch of the ophthalmic branch of the internal carotid artery.
  • the supraorbital artery to the lateral forehead and scalp as far up as the vertex. The supraorbital artery is a branch of the ophthalmic branch of the internal carotid artery.
• external carotid
  • the superficial temporal artery
    Superficial temporal artery
    In human anatomy, the superficial temporal artery is a major artery of the head. It arises from the external carotid artery when it bifurcates into the superficial temporal artery and maxillary artery....
    
     gives off frontal and parietal branches to supply much of the scalp
  • the occipital artery
    Occipital artery
    The occipital artery arises from the external carotid artery opposite the facial artery, its path is below the posterior belly of digastric to the occipital region. This artery supplies blood to the back of the scalp and sterno-mastoid muscles...
    
     which runs posteriorly to supply much of the posterior aspect of the scalp
  • the posterior auricular artery
    Posterior auricular artery
    The posterior auricular artery is a small artery and arises from the external carotid artery, above the Digastric muscle and Stylohyoid muscle, opposite the apex of the styloid process....
    
    , a branch of the external carotid artery, ascends behind the auricle to supply the scalp above and behind the auricle.

Note:
The walls of the blood vessels are firmly attached to the fibrous tissue of the superficial fascial layer, hence cut ends of vessels here do not readily retract; Even a small scalp wound may bleed profusely.

Innervation

Innervation is the connection of nerves to the scalp: the sensory and motor nerves innervating the scalp. The scalp is innervated by the following:

• Supratrochlear nerve
  Supratrochlear nerve
  The supratrochlear nerve is a branch of the frontal nerve, which itself comes from the ophthalmic division of the trigeminal cranial nerve.It is smaller than the nearby supraorbital nerve...
  
   and the supraorbital nerve
  Supraorbital nerve
  The supraorbital nerve is a terminal branch of the frontal nerve.It passes through the supraorbital foramen, and gives off, in this situation, palpebral filaments to the upper eyelid...
  
   from the ophthalmic division of the trigeminal nerve
  Trigeminal nerve
  The trigeminal nerve contains both sensory and motor fibres. It is responsible for sensation in the face and certain motor functions such as biting, chewing, and swallowing. Sensory information from the face and body is processed by parallel pathways in the central nervous system...
  
  
• Greater occipital nerve
  Greater occipital nerve
  The greater occipital nerve is a spinal nerve, specifically the medial branch of the dorsal primary ramus of cervical spinal nerve 2. This nerve arises from between the first and second cervical vertebrae, along with the lesser occipital nerve. It ascends after emerging from the suboccipital...
  
   (C2) posteriorly up to the vertex
• Lesser occipital nerve
  Lesser occipital nerve
  The lesser occipital nerve or small occipital nerve is a cutaneous spinal nerve arising between the second and third cervical vertebrae, along with the greater occipital nerve...
  
   (C2) behind the ear
• Zygomaticotemporal nerve
  Zygomaticotemporal nerve
  The zygomaticotemporal nerve or zygomaticotemporal branch is derived from the maxillary branch of the trigeminal nerve...
  
   from the maxillary division of the trigeminal nerve
  Trigeminal nerve
  The trigeminal nerve contains both sensory and motor fibres. It is responsible for sensation in the face and certain motor functions such as biting, chewing, and swallowing. Sensory information from the face and body is processed by parallel pathways in the central nervous system...
  
   supplying the hairless temple
• Auriculotemporal nerve
  Auriculotemporal nerve
  The auriculotemporal nerve is a branch of the mandibular nerve that runs with the superficial temporal artery and vein, and provides sensory innervation to various regions on the side of the head.-Origin:...
  
   from the mandibular division of the trigeminal nerve
  Trigeminal nerve
  The trigeminal nerve contains both sensory and motor fibres. It is responsible for sensation in the face and certain motor functions such as biting, chewing, and swallowing. Sensory information from the face and body is processed by parallel pathways in the central nervous system...
  
  

The innervation of scalp can be remembered using the mnemonic

Mnemonic

A mnemonic , or mnemonic device, is any learning technique that aids memory. To improve long term memory, mnemonic systems are used to make memorization easier. Commonly encountered mnemonics are often verbal, such as a very short poem or a special word used to help a person remember something,...

, "Z-GLASS" for, Zygomaticotemporal nerve, Greater occipital nerve, Lesser occipital nerve, Auriculotemporal nerve, Supratrochlear nerve and Supraorbital nerve.

Lymphatic drainage

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

Aesthetics

Aesthetics is a branch of philosophy dealing with the nature of beauty, art, and taste, and with the creation and appreciation of beauty. It is more scientifically defined as the study of sensory or sensori-emotional values, sometimes called judgments of sentiment and taste...

 of the face. Androgenic alopecia, or male pattern hair loss, is a common cause of concern to men. It may be treated with varying rates success by medication (eg finasteride

Finasteride

Finasteride is a synthetic antiandrogen that inhibits type II 5-alpha reductase, the enzyme that converts testosterone to dihydrotestosterone...

, minoxidil

Minoxidil

Minoxidil is an antihypertensive vasodilator medication which also slows or stops hair loss and promotes hair regrowth. Now off-patent, it is available over-the-counter for the treatment of androgenic alopecia. Minoxidil must be used indefinitely for continued support of existing hair follicles and...

) or hair transplantation. If the scalp is heavy and loose, a common change with ageing

Ageing

Ageing or aging is the accumulation of changes in a person over time. Ageing in humans refers to a multidimensional process of physical, psychological, and social change. Some dimensions of ageing grow and expand over time, while others decline...

, the forehead may be low, heavy and deeply lined. The brow lift procedure aims to address these concerns.

Hair transplantation

All the current hair transplantation

Hair transplantation

Hair transplantation is a surgical technique that involves moving individual hair follicles from one part of the body to bald or balding parts . It is primarily used to treat male pattern baldness. It this case, grafts containing hair follicles that are genetically resistant to balding are...

 techniques utilize the patient's existing hair. The aim of the surgical

Surgery

Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...

 procedure is to use such hair as efficiently as possible. The right candidates for this type of surgery are individuals who still have healthy hair on the sides and the back of the head in order that hair for the transplant may be harvested from those areas. Different techniques are utilized in order to obtain the desired cosmetic results; Factors considered may include hair color, texture, curliness, etc.

The most utilized technique is the one known as micro grafting because it produces naturalistic results. It is akin to Follicular Unit Extraction

Follicular Unit Extraction

Follicular unit extraction , also known as follicular transfer , is one of two primary methods of obtaining follicular units, naturally occurring groups of one to four hairs, for hair transplantation. The other method is called strip harvesting...

 although less advanced. A knife with multiple blades is used to remove tissue from donor areas. The removed tissue is then fragmented into smaller chunks under direct vision inspection (i.e., without a microscope).

Redness in scalp after surgery

After the surgery is complete, and during healing, scalp redness may occur. The main reason is that, during this period, areas of the head where transplantation has taken place are softer than normal. This is an expected consequence of the medical procedure. The plastic surgeon

Plastic surgery

Plastic surgery is a medical specialty concerned with the correction or restoration of form and function. Though cosmetic or aesthetic surgery is the best-known kind of plastic surgery, most plastic surgery is not cosmetic: plastic surgery includes many types of reconstructive surgery, hand...

 will usually have explained the likelihood of symptoms of apparent irritation, also having provided a series of indications and follow-up procedures to facilitate proper recovery. Such recommendations might include the application of ice and abstaining from strenuous physical activity in the short term.

Pathology

The scalp is a common site for the development of tumours including:

• epidermoid cyst
  Epidermoid cyst
  An epidermoid cyst is a benign cyst usually found on the skin. The cyst develops out of ectodermal tissue. Histologically, it is made of a thin layer of squamous epithelium.-Terminology:...
  
  
• pilar cyst
• actinic keratosis
  Actinic keratosis
  Actinic keratosis is a premalignant condition of thick, scaly, or crusty patches of skin. It is more common in fair-skinned people. It is associated with those who are frequently exposed to the sun, as it is usually accompanied by solar damage...
  
   and squamous cell carcinoma
  Squamous cell carcinoma
  Squamous cell carcinoma , occasionally rendered as "squamous-cell carcinoma", is a histologically distinct form of cancer. It arises from the uncontrolled multiplication of malignant cells deriving from epithelium, or showing particular cytological or tissue architectural characteristics of...
  
  
• basal cell carcinoma
  Basal cell carcinoma
  Basal-cell carcinoma is the most common type of skin cancer. It rarely metastasizes or kills. However, because it can cause significant destruction and disfigurement by invading surrounding tissues, it is still considered malignant. Statistically, approximately 3 out of 10 Caucasians may develop a...
  
  
• merkel cell carcinoma
  Merkel cell carcinoma
  Merkel cell carcinoma Merkel cell carcinoma Merkel cell carcinoma (also known as a "Cutaneous apudoma," "Primary neuroendocrine carcinoma of the skin," "Primary small cell carcinoma of the skin," and "Trabecular carcinoma of the skin"...
  
  

Scalp conditions

• Dandruff
  Dandruff
  Dandruff is the shedding of dead skin cells from the scalp . Dandruff is sometimes caused by frequent exposure to extreme heat and cold. As it is normal for skin cells to die and flake off, a small amount of flaking is normal and common; about 487,000 cells/cm2 get released normally after...
  
   -- A common problem due to the excessive shedding of dead skin cells from the scalp
• Seborrhoeic dermatitis
  Seborrhoeic dermatitis
  Seborrhoeic dermatitis is an inflammatory skin disorder affecting the scalp, face, and torso. Typically, seborrheic dermatitis presents with scaly, flaky, itchy, and red skin. It particularly affects the sebaceous-gland-rich areas of skin...
  
   -- a skin disorder causing scaly, flaky, itchy, red skin
  • Cradle Cap
    Cradle cap
    Cradle cap is a yellowish, patchy, greasy, scaly and crusty skin rash that occurs on the scalp of recently born babies. It is usually not itchy, and does not bother the baby. Cradle cap most commonly begins sometime in the first 3 months...
    
     -- a form of this disorder which occurs in newborns
• Cutis verticis gyrata
  Cutis verticis gyrata
  Cutis verticis gyrata is a superficial medical condition usually associated with thickening of the scalp. The condition was first described by Alibert in 1837...
  
   -- A descriptive term for a rare deformity of the scalp.
• Head lice
• Tycoon's cap
  Tycoon's cap
  Tycoon’s cap is a human disease of the scalp, classified as a mixed alopecia, characterized by minute, itchy pustules within the scalp.-Further reading:...
  
  , also known as acne necrotica
  Acne necrotica
  Acne necrotica present with a primary lesions that is a pruritic or painful erythematous follicular-based papule that develops central necrosis and crusting and heals with a varioliform scar....
  
   miliaris, characterized by pustules and itching.

See also

• Trichology
  Trichology
  Trichology is the branch of medicine that deals with the scientific study of the health of hair and scalp. Trichologists themselves are not normally licensed healthcare workers, although members of the medical profession can undertake courses and/or careers within trichology. Trichology can be...
  
   -- the scientific study of hair and scalp
• Trichodynia
  Trichodynia
  Trichodynia is a condition where the patient experiences a painful sensation on their scalp. The pain sometimes is described as burning. Often there is an underlying psychosomatic cause, such as stress, depression or anxiety....
  
   -- burning scalp syndrome
• Scalping
  Scalping
  Scalping is the act of removing another person's scalp or a portion of their scalp, either from a dead body or from a living person. The initial purpose of scalping was to provide a trophy of battle or portable proof of a combatant's prowess in war...
  
   -- the act of removing the scalp, usually with the hair, as a portable proof or trophy of prowess in war.
• Dermatillomania
  Dermatillomania
  Dermatillomania is an impulse control disorder characterized by the repeated urge to pick at one's own skin, often to the extent that damage is caused...
  
  - obsessive skin picking

External links

- "Integument: scalp, transverse" - "Integument: scalp"

• http://www.dartmouth.edu/~humananatomy/figures/chapter_47/47-1.HTM