Scalp Flashcards
Definition
Region covering skull vault.
Extent
Superciliary arches (eyebrows) anterior TO superior nuchal lines posterior AND superior temporal lines on each side.
Superficial to deep layers (5)
- Skin
- Connective tissue
- Epicranial aponeurosis
- Loose areolar tissue (sub-aponeurotic)
- Pericranium
Skin
Contains:
1. Hair follicles
2. Sebaceous glands
Firmly adherent to underlying layer.
Connective tissue
Senses fibrous tissue binding skin to 3rd layer.
It contains:
1. Vessels and nerves of the scalp
2. Rich in fat and fibrous septa
Epicranial aponeurosis
Wide tendon connecting frontal and occipital bellies of occipitofrontalis muscle.
Epicranial aponeurosis attachment anterior
Frontal bellies
Epicranial aponeurosis attachment posterior
- Occipital bellies
- External occipital protuberance
- Highest nuchal lines
Epicranial aponeurosis attachment on each side
Superior temporal lines
Loose areolar tissue
Facilitates movement of aponeurosis.
Pericranium
Periosteum covering skull vault and is adherent to suture lines.
Applied anatomy CT
- Infection in CT is limited due to fibrous septa presence.
- Cut wound leads to severe bleeding due to rich blood supply and inability of arteries to contract due to its attachment to fibrous septa.
Applied anatomy loose areolar tissue
- Loose areolar tissue is scalp dangerous area because infection can pass into cranial cavity via emissary veins present in it.
- Hemorrhage from emissary veins is large and separates scalp from skull bones.
Nerve supply
10 nerves on each side
5 in front of auricle
1. 4 sensory (trigeminal 5th cranial)
2. 1 motor (from facial nerve)
5 behind auricle
1. 4 sensory (C2 and C3 spinal nerves)
2. 1 motor (facial nerve)
4 sensory in front of auricle
- Supratrochlear nerve
- Supraorbital nerve
- Zygomaticotemporal nerve
- Auriculotemporal nerve
Motor in front of auricle
Temporal nerve
Sensory behind auricle
- Great auricular nerve: C2 and C3
- Lesser occipital: C2
- Greater occipital: C2
- Third occipital: C3
Motor behind auricle
Posterior auricular nerve
Supratrochlear and supraorbital nerve origin
Frontal branch ophthalmic nerve
Supratrochlear and supraorbital nerve supply
- Scalp anterior part
- Upper eyelid
- Forehead near median plane (Supratrochlear nerve)
- Scalp till lamboid suture (supraorbital nerve)
Supratrochlear nerve course
Passes through orbit superomedial angle
supraorbital nerve course
Passes through Supraorbital notch