Regional Anatomy Week 1 Lecture - Steve

What is the origin of the Platysma?

Covers upper parts of pectoralis major and deltoid muscles

What is the insertion of the platysma?

Blend with lower border of body of mandible and some of it blends with the lower lip and angle of mouth

What nerve innervates the platysma?

Cranial nerve VII - Facial

What is the origin of the Sternocleidomastoid

Anterior surface of manubrium of sternum and superior surface of clavicular head

What is the insertion of the sternocleidomastoid?

mastoid process of temporal bone and superior nuchal line of occipital bone

What is the nerve innervation the motor portion of the sternocleidomastoid?

Spinal accessory nerve XI

What is the nerve innervation the sensory portion of the sternocleidomastoid?

C2 and C3 ventral rami

What are all the infrahyoid muscles?

- Sternohyoid

- Omohyoid

- Thyrohyoid

- Sternothyroid

What are all the suprahyoid muscles?

- Digastric

- Stylohyoid

- Mylohyoid

What is the origin of sternohyoid?

posterior surface of the manubrium, and the sternal end of the clavicle

What is the insertion of sternohyoid?

Body of hyoid

What nerve innervates the sternohyoid?

Ansa cervicalis

What is the function of the sternohyoid?

depress hyoid bone after elevation during swallowing

What is the origin of the sternothyroid?

Posterior surface of manubrium of sternum

What is the insertion of the sternothyroid?

Oblique line of thyroid cartilage

What nerve innervates the sternothyroid?

Ansa cervicalis

What is the function of the sternothyroid?

Depress larynx

What is the location of the sternothyroid compared to the sternohyoid?

Sternothyroid is deep to sternohyoid

What is the origin of the thyrohyoid?

Oblique line of thyroid cartilage

What is the insertion of the thyrohyoid?

Into greater horn and body of hyoid

What nerve innervates the thyrohyoid?

- Hypoglossal nerve XII

What is the function of the thyrohyoid?

Depress hyoid or elevates larynx

What does the prefix Omo- mean?

Shoulder

What is the attachment points of the inferior belly of the omohyoid?

Superior border of scapula (medial to suprascapular notch) and passes lower part of posterior triangle of neck

- Ends with intermediate tendon

What is the attachment points of the superior belly of the omohyoid?

- Starts at intermediate tendon from inferior belly and goes vertical through anterior triangle of neck and attaches to the body of hyoid

What nerve innervates the omohyoid?

Ansa Cervicalis

What is the function of the Omohyoid?

Depress hyoid bone

What is the attachment points of the posterior belly of the Digastric?

- Attaches to digastric (mastoid) notch and becomes continous with intermediate tendon

What does the intermediate tendon of the digastric pierce through to attach to anterior belly?

Pierces stylohyoid

What is the attachment points of the anterior belly of the Digastric?

Attaches to digastric fossa of mandibel

What nerve innervates the anterior belly of the digastric?

Nerve to the myohyoid

What nerve innervates the posterior belly of the digastric?

Facial nerve CN VII

What is the function of the digastric muscle?

Depress mandible and elevates hyoid

What is the origin of the stylohyoid?

Styloid process

What is the insertion of the stylohyoid?

Into hyoid bone at junction of body and greater horn

What nerve innervated the stylohyoid?

Facial nerve CN VII

What is the function of the stylohyoid?

Elevates hyoid

What is the origin of the mylohyoid?

Mylohyoid line of mandible

What is the insertion of the mylohyoid?

Most posterior fibers: attach to body of hyoid and others terminate in midline raphe extending from mandible to hyoid

What nerve innervates the mylohyoid?

Nerve to the mylohyoid

What is the function of the Mylohyoid?

- Elevates floor of mouth and tongue

- Elevates hyoid

What is the origin of the scalenus anterior?

TP of C3-C4

What is the insertion of the scalenus anterior?

Superior surface and medial border of rib 1

What nerve innervates the scalenus anterior?

Ventral rami of C4-C6

What is the origin of the scalenus medius?

TP of C2-C7

What is the insertion of the scalenus medius?

Superior surface of rib 1

What nerve innervates the scalenus medius?

Ventral rami of C3-C8

What is the origin of the scalenus posterior?

TP of C4- C6

What is the insertion of the scalenus posterior?

Outer surface of 2nd rib

What nerve innervates the scalenus posterior?

Ventral rami of C6-C8

Which Scalenus muscle is the largest? Smallest?

Largest- Medius

Smallest- Posterior

What are the subdivisions of the anterior triangle of the neck?

- Submandibular (Digastric) Triangle

- Carotid Triangle

- Muscular triangle

- Submental triangle

What is the posterior border of the submandibular triangle?

Posterior belly of digastric and stylohyoid

What is the anterior border of the submandibular triangle?

Anterior belly of digastric

What is the superior border of the submandibular triangle?

Inferior border of body of mandible

What is the floor of the submandibular triangle?

Mylohyoid and hyoglassus muscles

What does the submandibular triangle contain?

- submandibular gland - facial artery and vein

- Submandibular lymph nodes

- Hypoglossal nerve

- Mylohyoid V.A.N.

What is the anterior and superior border of the carotid triangle?

Posterior belly of digastric

What is the anterior and inferior border of the carotid triangle?

Superior belly of omohyoid

What is the posterior border of the carotid triangle?

Anterior border of sternocleidomastoid

What is the contents of the Carotid triangle?

Carotid sheath

- common carotid artery

- internal jugular vein

- vagus nerve (CN X)

- CN XI, XII, ansa cervicalis, and internal and external laryngeal

What is the anterior border of the muscular triangle?

Anterior midline of neck

What is the posterior and superior border of the muscular triangle?

Superior belly of omohyoid

What is the posterior and inferior border of the muscular triangle?

Anterior border of sternocleidomastoid

What is contained in the muscular triangle?

- Sternohyoid and sternothyroid muscles

- Viscera of neck (ex. thyroid, trachea, etc.)

What is the inferior border of the submental triangle?

Body of hyoid

What is unique about the submental triangle?

Only unparied neck triangle

What is the lateral border of the submental triangle?

Anterior bellies of digastric muscles

What is the floor of the submental triangle?

Mylohyoid muscles

What is the apex of the posterior triangle of the neck?

Where the sternocleidomastoid and trapezius meet at superior nuchal line of occipital bone

What is the anterior boundary of the posterior triangle of the neck?

Posterior border of the sternocleidomastoid

What is the posterior boundary of the posterior triangle of the neck?

Anterior border of the trapezius

What is the inferior boundary of the posterior triangle of the neck?

Middle 1/3 of the clavicle

What does the posterior triangle of the neck contain?

-Arteries: subclavian artery , superficial (transverse) cervical artery,

suprascapular artery, dorsal scapular artery, occipital artery

- Veins: external jugular vein and subclavian vein

- Nerves: brachial plexus

accessory nerve, branches of cervical plexus