1.2 Scalp Flashcards
Where does the scalp extend to anteriorly?
the eyebrows (supra-orbital margins)
Where does the scalp extend to posteriorly?
the superior nuchal lines
Where does the scalp extend to laterally?
the superior temporal line
What bone is the superior nuchal line a part of?
occipital
Which 2 bones form the zygomatic arch?
Anteriorly = zygomatic bone Posteriorly = temporal bone
What type of joint is present between these 2 bones at the zygomatic arch?
Oblique suture
Name the 5 layers of the scalp
Skin Connective tissue (dense) Aponeurosis of the occipitofrontalis muscle (epicranial aponeurosis) Loose connective tissue Periosteum/pericranium
What does the epicranial aponeurosis connect?
The anterior (frontal) and posterior (occipital) bellies of the occipitofrontalis muscle (a muscle of facial expression)
What is the action produced by the contraction of the anterior belly of the occipitofrontalis?
Lifts eyebrows/forehead
What is the nerve supply to the anterior part of the scalp?
Trigeminal nerve (V) (all three branches - Opthalmic or V1; Maxillary or V2; Mandibular or V3)
What is the nerve supply to the posterior part of the scalp?
Cutaneous branches of cervical spinal nerves C2 & C3 (both the anterior and posterior rami)
Which structure forms the ventral rami of C5 to T1
the brachial plexus (the nerve supply to the upper limb)
In which layer of the scalp are the blood vessels present?
Dense connective tissue layer
Would wounds to the scalp bleed profusely or sparingly?
Profusely; dense connective tissue does not allow vessels to constrict at the same level as the rest of the body
Where does the supratrochlear artery branch from?
Internal carotid artery
Where does the supre-orbital artery branch from?
Internal carotid artery
Where does the superficial temporal artery branch from?
External carotid artery
Where does the posterior auricular artery branch from?
External carotid artery
Where does the occipital artery branch from?
External carotid artery
Where can the pulse of the STA be felt?
In front of the tragus of the ear
Name the 5 veins which drain the scalp
- Supra-orbital
- Supra-trochlear
- Facial
- Superficial temporal
- Occipital
Which 2 veins in the neck do most of the scalp veins drain into?
External Jugular
Internal Jugular
In addition to anastomosing with each other in scalp, what else can veins anastomose with?
Diploic veins in the skull bones (and through these to the venous sinuses of the brain) through valveless veins called emissary veins
What is diploe?
Spongey cancellous bone separating the inner & outer layers of the cortical bone of the skull
