Unit I: Superficial Structures of the Neck and Triangles of the Neck Flashcards
ORIGIN of the Platysma muscle
Superficial fascia over the PECTORALIS MAJOR and DELTOID muscles
INSERTION of the Platysma muscle
LOWER border of the MANDIBLE and the ANGLE of the mouth
NERVE supply to the Platysma muscle
Cervical branch of FACIAL nerve (C.N. VII)
FUNCTION of the Platysma muscle
DEPRESSES the Mandible and DRAWS down the corner of the mouth (shuts the mouth)
ORIGIN of the Sternocleidomastoid
1) Sternal head: Front of the MANIBRIUM
2) Clavicular head: MEDIAL third of the CLAVICLE
INSERTION of the Sternocleidomastoid
1) LATERAL surface of the MASTOID process
2) LATERAL half of the SUPERIOR NUCHAL LINE
NERVE supply to the Sternocleidomastoid
Spinal Accessory nerve (C.N. XI)
FUNCTION of Sternocleidomastoid
Chief FLEXOR of the HEAD
ORIGIN of the Trapezius
1) EXTERNAL occipital protuberance
2) Ligamentum nuchae
3) Spinous processes of seventh cervical and ALL thoracic vertebrae
INSERTION of the Trapezius
1) LATERAL third of the Clavicle
2) Spine of Scapula
3) Acromion process
NERVE supply to the Trapezius
1) Spinal Accessory nerve (C.N. XI)
2) C3 and C4 from Cervical plexus
FUNCTION of the Trapezius
1) UPPER portion ELEVATES
2) MIDDLE portion RETRACTS
3) LOWER portion DEPRESSES the scapula
This muscle functions in Scapulohumeral rhythm
Trapezius
The Trapezius helps with this by aiding in upward rotation of the scapula is produced primarily by the upper and lower fibers of the trapezius as well as the serratus anterior muscle.
Scapulohumeral rhythm
Origins of the Trapezius are all found here
Midline
Insertions of the Trapezius are all found here
Lateral
A pathological contraction of the SCM. The head is tilted TOWARD the affected side while the face is pointed AWAY from the affected side. There are 3 different types: Congenital, Muscular, and Spasmodic
Torticollis
This disorder results from a fibrous tissue tumor which develops at or shortly BEFORE birth, It is VERY rare
Congenital Torticollis
This disorder is caused by a birth injury during the birthing process
Muscular Torticollis
This disorder occurs in adults and is due to abnormal tonicity. Often responds well to chiropractic. Can be caused by a number of factors including: whiplash, sports injuries, viral infections. This is the MOST COMMON.
Spasmodic Torticollis
This is the LARGEST SUPERFICIAL vein of the neck. It drains the FACE and the SCALP and also contains a large amount of cerebral blood
External Jugular vein
The External Jugular vein is formed BELOW the PAROTID gland by the union of these two veins
1) Retromandibular vein
2) Posterior Auricular vein
This vein runs DOWNWARD and BACKWARD along the LATERAL surface of the SCM and empties into the SUBCLAVIAN vein
External Jugular vein
This tributary of the external jugular vein is formed at the joining of the maxillary vein and the superficial temporal vein in FRONT of the ear. This vein combines with the Posterior auricular vein to form the external jugular vein.
Retromandibular vein
This tributary of the external jugular vein formed from the collection of several venous tributaries situated BEHIND the ear. This vein combines with the Retromandibular vein to form the external jugular vein.
Posterior Auricular vein
This tributary of the external jugular vein drains blood from the posterior triangle and the occipital region.
Posterior external jugular vein
Tributaries of the External jugular vein
1) Retromandibular vein
2) Posterior Auricular vein
3) Posterior External jugular vein
4) Anterior jugular vein
5) Transverse cervical vein
6) Suprascapular vein
This is usually NOT seen topographically with normal venous pressure
Causes include:
•CHF
•superior vena cava obstruction can cause distention
•tumors (lung CA)
•Cardiac tamponade
Normal in: opera singers
Prominent External Jugular vein
This structure is found along the External jugular vein SUPERFICIAL to the the SCM
Superficial cervical lymph nodes
The TWO triangles of the neck that are divided by the SCM
1) Posterior triangle (behind SCM)
2) Anterior triangle (in front of SCM)
Anterior border of the Posterior Triangle
POSTERIOR border of the SCM
Posterior border of the Posterior Triangle
ANTERIOR border of the Trapezius
Inferior border of the Posterior Triangle
SUPERIOR border of the middle third of the CLAVICLE
This triangle lies BEHIND the SCM and does NOT contain any important visceral structures
Posterior Triangle
Superior border of the Anterior triangle
INFERIOR border of the MANDIBLE
Anterior border of the Anterior triangle
ANTERIOR midline
Posterior border of the Anterior triangle
ANTERIOR border of SCM
The ____ of the Anterior triangle lies INFERIORLY at the jugular notch.
Apex
The ____ of the Anterior triangle is formed by the investing layer of the deep cervical fascia, superficial cervical fascia, and platysma
roof
Contents of the Anterior triangle
1) Submental triangle
2) Submandibular triangle (digastric)
3) Carotid triangle
4) Muscular triangle
This division of the anterior triangle is the ONLY division that is UNPAIRED
Submental triangle
Boundaries of the Submental triangle
Left and right ANTERIOR bellies of digastric and the body of the HYOID bone
Forms the floor of the Submental triangle
Mylohyoid muscle
This part of the anterior triangle contains minor veins and lymph nodes (drain lower lymph and lower floor of mouth)
Submental triangle
This part of the anterior triangle is found BELOW the mandible and is paired.
Submandibular triangle
Boundaries of the Submandibular triangle
1) Inferior border of the mandible
2) Anterior belly of the digastric
3) Posterior belly of the digastric
These muscles form the FLOOR of the Submandibular triangle
Mylohyoid and Hyoglossus muscles
This submandibular gland, parotid and sublingual, the internal carotid artery, facial artery, internal jugular vein, glossopharyngeal nerve and vagus nerve are found in this triangle
Submandibular triangle
This area of the ANTERIOR triangle contains many important neurovascular structures
Submandibular (digastric) triangle
This is the most superficial and second largest salivary gland
Submandibular salivary gland
This artery bifurcates in coratid triangle into internal and external coratid arteries
Common carotid artery
This part of the anterior triangle is formed from the posterior belly of the digastric, the superior belly of the omohyoid and the anterior border of the SCM
Carotid triangle
These muscles form the floor of the coratid triangle
Thyrohyoid, hyoglossus and inferior and middle constrictor muscles
Contents of the Coratid triangle
Parts of the common and internal coratid arteries, external coratid artery and three of its branches (superior thyroid artery, facial artery, lingual artery), and the tributaries for the internal jugular vein
This part of the anterior triangle is surrounded by the superior belly of the omohyoid, anterior midline of the neck, and the anterior border of the SCM. (meet at midline of the neck)
Muscular triangle
This forms the floor of the muscular triangle
Posterior layer of the pretracheal fascia
Contents of the muscular triangle
Sternohyoid, and sternothyroid muscles (thryoid gland, trachea, and esophagus)
This bone is located between the MANDIBLE and the LARYNX and serves as a point of attachment for many muscles. Does NOT articulate with any bones and is completely suspended by muscles and ligaments
Hyoid bone
Parts of the Hyoid bone
1) Body
2) greater horn
3) lesser horn
This part of the hyoid bone is located anterior and inferior `
Body
This part of the hyoid bone is located on each side of the bone and is a site for muscle attachments
Greater horn
This part of the hyoid bone is NOT always present because it is cartilaginous and ossifies irregularly. Not always ossified.
Lesser horn
This part of the hyoid bone is often broken in cases of strangulation
Lesser horn
The function of this bone is to serve as a site of muscle attachment specifically for the Stylohyoid ligament
Hyoid bone
This group of muscles is made up of 4 ribbion-like muscles that attach to the hyoid bone. They function primarily to move the hyoid bone and larynx
Infrahyoid muscles
Muscles that make up the infrahyoid muscles
1) Omohyoid
2) Sternohyoid
3) Sternothyroid
4) Thyrohyoid
Origin of the Omohyoid
Inferior belly– upper border of scapula
Superior belly – intermediate tendon of inferior belly
Insertion of the Omohyoid
Inferior belly– tendon deep to the SCM muscle
Superior belly – body of the hyoid bone
Nerve supply for the Omohyoid
Ansa cervicalis
C1, C2, C3
Function of the Omohyoid
Depresses hyoid bone and larynx. (runs along the upper border of the scapula)
Origin of the Sternohyoid
Posterior surface of manubrium, medial end of clavicle
Insertion of the Sternohyoid
Body of the hyoid bone
Nerve supply to the Sternohyoid
Ansa Cervicalis (C1, C2, C3)
Function of the Sternohyoid
Depresses the hyoid bone and larynx
Origin of the Sternothyroid
Posterior surface of the manubrium, inferior to the origin of the sternohyoid
Insertion of the Sternothyroid
Oblique line of the lamina of the thyroid cartilage
Nerve supply to the Sternothyroid
Ansa Cervicalis (C1, C2, C3)
Function of the Sternothyroid
Depresses the larynx
Origin of the Thyrohyoid
Oblique line on the lamina of the thyroid cartilage
Insertion of the Thyrohyoid
Body of the hyoid bone
Nerve supply to the Thyrohyoid
C1 through hypoglossal nerve
Function of the Thyrohyoid
Depresses the hyoid bone
These two muscles make up the SUPERFICIAL layer of the infrahyoid muscles
Omohyoid and sternohyoid
These muscles make up the DEEP layer of the infrahyoid muscles
Sternothyroid and thyrohyoid
Why all muscles to DEPRESS the HYOID bone and LARYNX? [functions]
1) SWALLOWING (most important)
2) Speech
3) breathing or respiration
4) If hyoid is fixed by infrahyoid muscles, that CHANGES the FUNCTION of the DIGASTRIC muscle (depresses/closes mandible)