inferior border of the mandble, superficial fascia of the lower face, and skin
Insertion of the Platysma Muscle
fascia overlying the superior parts of the pectoralis major and the deltoid muscle
Innervation of the Platysma Muscle
Cervical Branch of the Facial Nerve
Action of the Platysma Muscle
depress the corners of the mouth
widens the mouth (expresses sadness)
superiorly raises skin of neck when teeth are clenched (showing tension)
Blood Supply for the Platysma Muscle
transverse cervical a, v.
cutaneous cervical a, v.
anterior jugular v.
facial a, v.
Origin for the Sternocleidomastoid Muscle
lateral surface of mastoid process of temporal bone
lateral half of superior nuchal line
Insertion for the Sternocleidomastoid Muscle
sternal head: anterior surface of the manubrium of the sternum
costal head: superior surface of medial 3rd of clavicle
Innervation for the Sternocleidomastoid Muscle
Spinal Accessory Nerve (CN XI)
C2 & C3 nerves
Action of the Sternocleidomastoid Muscle
unilateral: tilts neck to same side; rotates it so face is turned superiorly toward opposite side
bilateral: flexes the cervical vertebrae so the chin is able to head toward the manubrium, extends superior cervical vertebrae while flexing inferior cervical vertebrae so chin is thrust forward with head kept level, extends neck at atlanto-occipital joints
Blood Supply for the Sternocleidomastoid Muscle
superior thyroid a, v.
Anterior Scalene Muscle Origin
anterior tubercles of transverse process of cervical vertebrae C3 - C6
Anterior Scalene Muscle Insertion:
Anterior Scalene Muscle Innervation
Cervical Spinal Nerves C4 - C6
Anterior Scalene Muscle Action:
laterally flex the neck, and to elevate the 1st Rib during forced respiration
Anterior Scalene Muscle Blood Supply:
Internal Jugular v.
Transverse Cervical a, v.
Middle Scalene Muscle Origin
posterior tubercles of transverse processes of C4 -C7
Middle Scalene Muscle Insertion:
superior surface of 1st Rib
posterior groove for subclavian a.
Middle Scalene Muscle Innervation
Anterior Rami of Cervical Spinal Nerves
Middle Scalene Muscle Action
flex neck laterally; elevate 1st Rib during forced inspiration
Middle Scalene Muscle Blood Supply:
Internal Jugular V.
Transverse Cervical a., v.
Posterior Scalene Muscle Origin
posterior tubercles of transverse processes C4 -C6 vertebrae
Posterior Scalene Muscle Insertion
external border of second rib
Posterior Scalene Muscle Innervation:
anterior rami of cervical spinal nerve C7 and C8
posterior scalene muscle action:
flex neck laterally, elevate 2nd rib during forced inspiration
posterior scalene muscle blood supply:
transverse cervical a, v.
Longus Colli Origin:
Bodies of C1 - C3, transverse processes of C3 - C6, anterior tubercle of C1
Longus Colli Insertion:
transverse processes of C3 -C5
bodies of C5 - T3
Longus Colli Innervation:
Anterior Rami of C2 - C6
Longus Colli Action:
flex neck with rotation to opposite side if acting unilaterally
longus colli blood supply:
vertebral a, v.
posterior belly of the digastric muscle origin
mastoid notch of temporal b.
posterior belly of digastric muscle insertion
intermediate tendon to greater horn and body of hyoid b.