Thorax dissection Flashcards Preview

Year 2 Semester 2 > Thorax dissection > Flashcards

Flashcards in Thorax dissection Deck (61)
Loading flashcards...

What is the origin, insertion, action and innervation of brachiocephalicus?

O= clavicle/clavicular intersection (no clavicle in dog)
I=cleidobrachialis: distal cranial humerus
cleidocervicalis: fibrous raphe of neck
cleidomastoideus: mastoid part of temporal bone
A= advances the limb, extends shoulder, draws the neck and head to the side
In= accessory nerve and ventral branches of cervical spinal nerves


Which muscle forms the dorsal boundary of the jugular furrow?
What about the ventral boundary?

Dorsal: brachiocephalicus
Ventral: sternocephalicus


Where would you raise the jugular vein when taking blood?

Jugular groove at the base of the neck, beside the trachea


What are the cranial and caudal parts of the sternum called?

Cranial: manubrium
Caudal: xiphoid process


Name the bones of the larynx, from cranial to caudal

Arytenoids (paired)


What is the name of the joint between the mandible and skull?

Temporomandibular joint


What name is given to the joint between the atlas and axis?

Atlanto-axial joint


What name is given to the joint between the atlas and the skull?

Atlanto-occipital joint


Which side of the recurrent laryngeal nerve is more prone to damage in horses?
What does it cause?

Left nerve is longer, due to its extended length around the base of the heart. Also therefore more common in larger horses
Causes 'roaring'-unable to fully open the larynx, air makes a whistling/roaring noise as it passes through


What shape are the cartilage rings in cats and dogs?



What is the origin, insertion, action and innervation of sternocephalicus?

O= manubrium of sternum
I= mastoid process of skull, nuchal crest of occipital bone
A= draws head and neck to the side
In= accessory nerve and ventral branches of cervical spinal nerves


Sternothyrohyoideus (paired, left and right) splits into what?

Ventromedially: sternohyoideus
Dorsolaterally: sternothyroideus


Where do the left and right common carotid arteries arise from?

Brachiocephalic trunk


In which direction do the sympathetic and parasympathetic fibres travel in the vagosympathetic trunk?

Sympathetic: preganglionic and postganglionic axons course cranially to structures in the head
Parasympathetic: preganglionic axons course caudally down the neck to thorax and abdomen


Which hormones does the thyroid gland produce?

T3 (triiodothyronine)
T4 (thyroxine)


Where are the parathyroid glands located?

Two on each thyroid gland. One on the lateral aspect of the cranial pole, one on the tracheal surface of the caudal pole


What is the role of the parathyroid gland?

Produces parathyroid hormone, which increases the concentration of Ca2+ in the blood


Where is the recurrent laryngeal nerve located?

Attached to the dorsolateral surface of trachea


What is the origin, insertion, action and innervation of the superficial pectorals?

2 parts
O= cranial sternum
I= cranial part: deltoid tuberosity of humerus
caudal part: medial fascia of forelimb
A= adducts limb
In= cranial pectoral nerves (C7, C8)


What is the origin, insertion, action and innervation of the deep pectorals?

2 parts
O= ventral sternum
I= major portion: lesser tubercle of humerus
caudal part: medial brachial fascia
A= adducts limb
In= C8, T1


Which vessel does the axillary artery arise from?
What are the other main branches of this vessel? (4)

Subclavian artery becomes axillary artery

Vertebral artery
Costocervical trunk
Superficial cervical artery
Internal thoracic artery


Where does serratus dorsalis originate and insert?

O= dorsal fascia
I= ribs


What is the origin, insertion and action of scaleneus?

O= transverse processes of caudal cervical vertebrae
I= first few ribs
A= helps to stabilise ribs during inspiration


Which nerves make up the brachial plexus?

C6, C7, C8, T1


In which direction do fibres run of the external intercostals run? What is the function of this muscle?
What about internal intercostals?

Externals: Caudoventrally. Pull ribs cranially and out during inspiration.

Internals: Caudodorsally. Pull ribs caudally and in during expiration.


What would happen if you cut into the parietal pleura of the ribs?
What does this tell you about the pressure inside the pleural cavity?

Lungs would immediately recoil and air would rush into the pleural cavity. Ribs would rise up.

Negative pressure; it is below atmospheric pressure


What is contained within the mediastinum?

Heart, aorta, trachea, tracheal bifurcation, thymus, lymph nodes, oesophagus, vagus nerves, other nerves and vessels


What name is given to the portion of mediastinum covering the heart?

Pericardial mediastinal pleura


The mediastinum can be divided into which 3 parts?

Cranial part (lying cranial to heart)
Middle part (containing the heart)
Caudal part (lying caudal to heart). Thin.


Why does the caudal mediastinum deviate to the left?

Follows on from the left apex of the heart