Anatomy 5 Flashcards
What are the boundaries of the posterior triangle in the neck?
1) Posterior border of the sternocleidomastoid muscle
2) Anterior border of the trapezius muscle
3) The middle 1/3 of the clavicle
The trunks of what descend posteroinferiorly through the posterior triangle of the neck?
The trunks of the brachial plexus
Why would a stab wound to the posterior triangle of the neck possibly lead to breathlessness and paralysis of the upper limb?
1) Could stab the apex of the lung leading to pneumothorax
2) May damage the upper trunk of the brachial plexus - branches of this innervate most muscles of the arm so can lead to paralysis of arm
The accessory nerve courses posteroinferiorly through the posterior triangle of the neck, which 2 muscles are supplied by this nerve?
Sternocleidomastoid and trapezius muscles
What are the boundaries of the anterior triangle of the neck?
Anterior border of the sternocleidomastoid
Inferior border of the mandible
Midline of the neck
What is the laryngeal prominence?
Prominence in the midline of the thyroid cartilage
Is the hyoid bone inferior or superior to the thyroid cartilage?
Superior
What 3 parts make up the thyroid gland?
Right lobe
Left lobe
isthmus (in middle)
Can the thyroid gland be palpated?
No, the lobes lie deep to muscle and the isthmus cannot be palpated either
The external jugular vein descends through the subcutaneous tissue of the neck on the surface of what muscle?
The sternocleidomastoid
What are the surface markings of the external jugular vein?
4cm along a line from middle of clavicle to angle of mandible is where the vein pierces deep fascia
Which muscles lie deep to the omohyoid and sternohyoid muscles?
The sternothyroid and thyrohyoid muscles
What is the general function of the sternohyoid muscle?
Depresses the hyoid bone after swallowing
What is the function of the omohyoid muscle?
Depresses and fixes the hyoid bone
What is the nerve supply to the sternohyoid and omohyoid muscles?
Anterior rami of C1 to C3 through the ansa cervicalis
Where does the sternohyoid muscle run between?
From the sternum to the hyoid bone
Where does the sternothyroid muscles run from?
The sternum to the thyroid cartilage
Where does the thyrohyoid muscle run between?
From the thyroid cartilage to the hyoid bone
What are the 4 infra hyoid muscles?
1) Sternohyoid
2) Sternothyroid
3) Thyrohyoid
4) Omohyoid
Where does the cricothyroid membrane run between?
Between the thyroid cartilage and the cricoid cartilage
Where does the cricoid cartilage lie?
Inferior to the thyroid cartilage
What are the 4 suprahyoid muscles?
1) Stylohyoid
2) Digastric
3) Mylohyoid
4) Geniohyoid
What are the attachments of the 2 bellies of the digastric muscle?
Anterior belly
Origin = Digastric fossa on the lower side of the mandible
Posterior belly
Origin = mastoid notch on the medial side of the mastoid process of the temporal bone
Insertion of both =Attachment of tendon of 2 bellies on hyoid bone
What is the function of the 2 bellies of the digastric muscle?
Anterior belly = opens mouth by lowering mandible and raises hyoid bone
Posterior belly = pulls hyoid bone superiorly and posteriorly
What is the carotid sheath?
Thick layer of fascia that binds together the common carotid artery, the internal jugular vein and the vagus nerve
In the upper part of the neck what does the carotid sheath contain?
The internal carotid artery
Internal jugular vein
last four cranial nerves