Muscles of Neck Flashcards
NECK
ANTERIORLY - Lower border mandible to upper surface manubrium of sternum
POSTERIORLY - Superior nuchal line (on occipital bone) to Intervertebral disc C7 and T1
FASCIA OF NECK
SUPERFICIAL Fascia
- thin sheet muscle (platysma)
DEEP Fascia
- Investing layer: surrounds all structures in neck
- Prevertebral layer: surrounds vertebral column and muscles of back
- Pretracheal layer: encloses viscera neck
- Carotid sheaths: surrounds Common Carotid Artery, Internal Carotid Artery, Internal Jugular Vein and Vagus Nerve
SUPERFICIAL DRAINAGE NECK (External Jugular Vein)
Formed Posterior to mandible - union posterior auricular and retromandibular veins
Superficial to SternocIeidomastoid
Pass DEEP to clavicle, drains into Subclavian vein
TRIBUTARIES:
- Posterior External Jugular Vein
“ Transverse Cervical Vein
- Suprascapular Vein
SUPERFICIAL DRAINAGE (Anterior Jugular Vein)
Drains Anterior aspect
Venous channels fuse Superior to Hyoid Bone
Either side of midline
Inferiorly, medial Sternocleidomastoid
Drains into Subclavian vein
Anterior Jugular vein communicates via Jugular Venous Arch (suprasternal notch)
SUPRAHYOID MUSCLES
Related to Submandibular and Submental triangles
- Stylohyoid
- Digastric (Posterior/Anterior)
- Mylohyoid
- Geniohyoid
STYLOHYOID (Origin)
Base Styloid process
STYLOHYOID (Insertion)
Lateral body Hyoid
STYLOHYOID (Innervation)
Fascial Nerve
STYLOHYOID (Action)
Pulls hyoid posterosuperior direction (during swallowing)
DIGASTRIC - POSTERIOR BELLY (Origin)
Mastoid process temporal bone
DIGASTRIC - POSTERIOR BELLY (Insertion)
Attachment tendon (tendon attach Hyoid)
DIGASTRIC - POSTERIOR BELLY (Innervation)
Fascial Nerve
DIGASTRIC - POSTERIOR BELLY (Action)
Pulls Hyoid posterosuperior direction (when mandible fixed)
DIGASTRIC - ANTERIOR BELLY (Origin)
Digastric fossa mandible
DIGASTRIC - ANTERIOR BELLY (Insertion)
Attached tendon (tendon to Hyoid)
DIGASTRIC - ANTERIOR BELLY (Innervation)
Mylohyoid Nerve (branch Mandibular Nerve)
DIGASTRIC - ANTERIOR BELLY (Action)
Opens mouth - lowering mandible (Hyoid fixed)
MYLOHYOID (Origin)
~ Superior to Digastric Anterior Belly
Mylohyoid line mandible
MYLOHYOID (Insertion)
Hyoid Body
MYLOHYOID (Innervation)
Mylohyoid Nerve (branch Mandibular Nerve)
MYLOHYOID (Action)
Support and Elevation floor mouth
Elevation Hyoid
GENIOHYOID (Origin)
~ Superior to floor oral cavity
Genial Tubercle (Mental spine) of mandible
GENIOHYOID (Insertion)
Anterior body Hyoid
GENIOHYOID (Innervation)
Anterior ramus C1
GENIOHYOID (Action)
Mandible fixed = Pulls Hyoid Anteriorly
Hyoid fixed Pulls mandible Inferiorly
INFRAHYOID MUSCLES
Muscular Triangle ~ known as “Strap” muscles
- Sternohyoid
- Omohyoid
- Thyrohyoid
- Sternothyroid
STERNOHYOID (Origin)
Posterior aspect Sternodavicular joint
STERNOHYOID (Insertion)
Hyoid body, medial to omohyoid
STERNOHYOID (Innervation)
Anterior ramus C1-C3 via Ansa Cervicalis