Anatomy 3 - Head And Neck: Scalp, Face, Mastication, Neck Flashcards
Joints of the skull
- mostly solid joints: bones linked by solid fibrous joints called sutures - don’t allow much movement
- TMJ: synovial joint. Mandibular fossa temporal/head mandible. Held by ligaments: articular disc and lateral ligament
Clinical issues of TMJ
- dislocation is nearly always forward + down
- disc thinning and clicking
5 layers of the scalp
- Skin: sweath , sebaceous, vessels, hairs
- Connective tissue: dense, thick, fat, vessels
- Aponeurosis: membrane and muscles
- Loose connective tissue: spongy, where movement occurs
- Pericranium: dense cell layers: can become infected
Clinical issues of the scalp
- infections of pericranium can go into brain
- tears in loose connective tissue
- Bleed a lot because very vascularized
Mastication muscle characteristic
- act on the mandible
- supplied by the motor branch of trigeminal V nerve (V3: mandibular)
- pretty bulky
- derive from 1st pharyngeal arch
- function: chew-mash food, speech
Mastication muscles: Masseter
- attachment
- function
- From zygotic, maxilla
- to : outer mandible
- function: elevate jaw, close mouth
Mastication muscle: Temporalis
- attachment
- function
- from temporal fossa
- to coronoid mandible (anterior)
- Function: elevate and retract jaw
Mastication muscles: lateral pterygoid
- attachment
- function
- From: sphenoid
- to: neck/head mandible, articular disc of TMJ
- Function: depress and protract jaw
Mastication muscles: medial pterygoid
- attachment
- function
- From: sphenoid
- to: inner mandible
- Function: elevate and protract jaw
Muscle of facial expression characteristics
- thin, superficial, elastic sheets
- originate from 2nd pharyngeal arch
- Motor: facial nerve + some autonomic supply
- Function: face expressions
Muscles of facial expression: Frontalis
- Forehead wrinkles
- eyebrow raie
- attach to galeal aponeurosis
Muscle of facial expression: orbicularis oculi
- Sphincter
- close eye
Muscle of facial expression: orbicularis oris
- Sphincter around mouth
- close mourth
- lip position speech
Muscles of facial expressionL Zygomaticus major
- elevate mouth angle
- attach to angle of mouth
Muscle of facial expression: Platysma
- lowers jaw-lip
- tenses neck
Muscles of facial expression: buccinator
- deep/thick
- put cheeks together
- important in suckling in baby
- signature: parotid duct goes through it
Anterior neck muscle characteristics
- not in face but have impact because nerve smorgasbord
- clinical issues: neck lumps and bumps
- two muscle groups: suprahyoids and infrahyoids
Hyoid bone
- not like the others
- attach/fixation point
- speech/swallowing
Suprahyoid muscle characteristics
- bring hyoid up
- raise pharynx: important in swallowing
Suprahyoid muscles: stylohyoid
- supplied by facial VII
- from temporal (styloid)
- to hyoid bone
- function: elevate and fix the hyoid, particularly during swallowing
Suprahyoid muscles: digastric
- anterior belly supplied by V3 (mandibular)
- posterior belly supplied by fascial VII
- from: temporal (mastoid)
- to mandible
- function: depress jaw and elevate-fix hyoid
Suprahyoid muscles mylohyoid
- supplied from V3
- from Mandible (mylohyoid)
- to: hyoid
- function: depress jaw, elevate - fix hyoid when mouth is closed
- Suprahyoid muscles: geniohyoid
- Supplied by C1 through XII
- from mandible
- to hyoid
- Function: depress jaw/elevate-fix hyoid
Infrahyoid muscles: sternoihyoid
- supplied by C1-3
- From: sternum
- To: Hyoid
- Function: fix, depress hyoid
Infrahyoid muscles: omohyoid
- supplied by C1-3
- attach from scapula to hyoid
- Function: fix and depress hyoid
- becomes tendicous over IJV and then muscly again
Infrahyoid muscles: thyrohyoid
- supplied by C1 through XII
- thin flat muscle
- attach from thyroid to hyoid
- function: fix and depress hyoid
Infrahyoid muscles: Sternothyroid
- supplied by C1-3
- deep
- attach from sternum to thyroid
- functionL fix depress hyoid
Supply of face: sensory nerves
- Trigeminal (V) three branches:
- ophtalmic (V1)
- maxillary (V2)
- Mandibular (V3) : only motor part of trigeminal
Supply of face: motor nerves
- facial: muscle of facial expression + some suprahyoids
- Mandibular (V3): chunky and deep: muscle of mastication. Some suprahyoids
- some suprahyoids and infrahyoids supplied by cervical plexus
