Anterior Triangle Flashcards
What are the boundaries of the anterior triangle./
- anterior border SCM M
- inf border of Mandible
- midline of neck
What muscles are within the anterior triangle?
4 SUPRAHYOID MS:
- stylohyoid
- diagastric
- mylohyoid
- geniohyoid
4 INFRAHYOID:
- omohyoid
- sternohyoid
- thyrohyoid
- sternothryoid
what vessels are within the anterior triangle?
- COOMON CAROTID ARTERY: passes through AT and bifurcates within triangle into ext and int carotid arteries
- INTERNAL JUGULAR VEIN: drains blood from head and neck
CRANIAL nerves in anterior triangle?
- facial [VII]
- glossopharyngeal [IX]
- vagus [X]
- Accessory [XI’
- Hypoglossal Nerves [XII]
What are the 2 origins and insertion of the diagastric muscle?
What are their innovations and function?
Origin:
- AB: diagastric fossa on lower inside mandible
- PB: mastoid notch on medial side of mastoid prcs temp bone
INSERTION: attachment of tendon between 2 bellies of body of hyoid bone
INNERVATION:
- AB: mylohyoid N fr inf alveolar br of Mandibular N [V3]
- PB: facial nerve [VII]
FUNCITON: opens mouth by lowering mandible & raises hyoid bone
Stylo Hyoid Muscle
Base of styled process–> lateral area of body of HB
- INNERVATION”: FACIAL N [VII]
- FUNCT: pulls HB upward in a posterosuperior direction
geniohyoid
inferior mental soine on inner surface of mandible–> ant surface of bod of HB
INN: br fr anterior ramus of C1 (carried along the hypoglossal nerve [XII]
FUNCT:
- fixed mandible elevates
- pulls HB forward
- fixed HB pulls mandible downward and inward
STERNOHYOID
posteiror aspect of sternoclavicular joint and adj manubrium of sternum–> body of hyoid bone medial to att of omohyoid muscle
INN: anterior rami of C1-C3 through nasa cervalis
F: depresses HB after swallowing
omohyoid
sup bord scapula medial to suprascapular notch–> lower border of body of hyoid bone just lateral to att of sternohyoid
I: ant rami of C1-C3 through ansa carvels
F: depresses and fixes HB
Thyrohyoid
oblique line on lamina of thyroid cartilage–> great horn adj aspect of bod of HB
INN: fibres from ant ramus of C1 carried along hypoglossa nerve [XII]
F: depresses HB, but when HB is fixed raises larynx
STERNOTHYROID:
post surface manubrium of sternum–> oblique line on lamina of thyroid cartilage
I: ant rami of C1-C3 through nasa cervicalis
F: draws (thyroid cartilage) downward
4 triangle of the anterior triangle
- submandibular : contains submandibular gland, lymph nodes FACIAL ARTERY AND VEIN
- submental triangle: contains submental lymph nodes
- MUSCULAR : no vessels, contain infrahyoid muscles, pharync and thyroid and parathyroid glands
- CAROTID : CCA, IJV and hypoglossa and vagus NERVES
Submental triangle BOUNDARIES
Mandibular symphysis; anterior belly of digastric muscle; body of hyoid bone
submandibular boundaires
- lower border mandible
- anterior bellyy diagastric muscle
- posterior belly of digastric muscle
