The lung is held in place by structures that enter the lung at the ___.
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hilus
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The lung is held in place by structures that enter the lung at the ___.
hilus
The muscular diaphragm forms the ___ boundary of the thoracic cavity.
caudal
The costal parietal pleura lines the ___ of the thoracic cavity.
rib cage
To reflect the left external abdominal oblique, cut the ___ and ___ attachments.
costal, sternal
The layers of serous membranes that compose the borders of each cavity include the ___ pleura and the visceral pleura.
parietal
Rib 13 is known as the '___ floating' rib.
free
The proximal attachments of the external abdominal oblique, rectus abdominis, and transversus abdominis are to be demonstrated on a ___ .
skeleton
Define the anatomical term ___ and explain its relevance as a landmark to this dissection.
thoracolumbar fascia
After reflecting the external abdominal oblique, identify the ___ muscle.
rectus abdominis
When cutting the ribs, start with rib ___ and continue both cranially and caudally.
8
The ___ is the central compartment of the thoracic cavity that contains the heart.
mediastinum
In the thoracic region, the head of a rib typically articulates with ___ vertebral bodies.
two
Ribs 9-12 are termed 'false ribs' because they attach indirectly to the sternum via the ___ arch.
costal
The muscles of ventilation include the ___, internal and external intercostals, and some abdominal wall muscles.
scalenus
On a skeleton, demonstrate the attachments of the ___ muscles: superficial pectoral, deep pectoral, latissimus dorsi, serratus ventralis, and epaxial muscles.
following
The abdominal wall muscles mentioned are the rectus abdominis and the ___ ___ ___ ___.
external abdominal oblique
While standing at a skeleton, explain the directional terms: dorsal, ventral, cranial, ___, axial, abaxial.
caudal
The plica venae cavae is important because it provides support for the ___ as it enters the heart.
vena cava
Structures that pass from the mediastinum through the thoracic inlet cranially include the ___ and ___.
cranial vena cava, thymus
The term 'pericardium' refers to the ___ that surrounds the heart.
fibrous sac
The intercostal muscles aid in changing the size of the thoracic cavity during ___.
respiration
The ___ notch of the right lung is located at the fourth and fifth intercostal spaces.
cardiac
To clean the dissection table, use the table cleaning solution found in ___ buckets.
red
Segmental cutaneous nerves that supply the thoracic body wall are noted for their ___ nature.
segmental
To identify if a lung is right or left, you can observe the orientation of the ___ lobes.
cranial and caudal
The four extrinsic limb muscles together form a muscular ___ that supports the trunk.
sling
The bony landmarks of the thorax include the thoracic vertebrae ___, ribs ___, and sternebrae and costal cartilages ___.
dorsally, laterally, ventrally
Understanding the pericardium is useful for a future veterinarian because it helps in ___ related to heart conditions.
diagnosing and treating diseases
Rib 13 is designated a 'floating rib' because it does not attach to the ___.
sternum
The left caudal lung lobe is stabilized by a double fold of connecting pleura called the ___ ___.
pulmonary ligament
After dissection, the lungs should be moistened and kept in a small ___ bag.
plastic
The transversus abdominis muscle is the ___ muscle of the abdominal wall.
deepest
To orient yourself in the thoracic cavity, identify the ___, sternum, and thoracic vertebra.
ribs
The ___ nerve follows a similar course to the phrenic nerve but passes dorsal to the hilus of the lung.
vagus
The collection of structures entering/exiting the lung is referred to as the ___ of the lung.
hilus
On the ventral surface, the ___ is a prominent landmark for abdominal surgery.
umbilicus
Palpate caudal to the costal arch to feel the ___ deep to the body wall.
abdominal viscera
The costal parietal pleura lines the lateral thoracic walls along the ___.
ribs
The mediastinal parietal pleura varies in size, shape, and position along its ___.
length
Costal foveae are unique to ___ vertebrae and serve as sites for articulations with the heads of ribs.
thoracic
Structures that pass from the mediastinum through the diaphragm caudally include the ___ and ___.
caudal vena cava, azygous vein
The ___ nerve runs from the thoracic inlet to the diaphragm, passing ventral to the hilus of the lung.
phrenic
The serous membrane fold surrounding the caudal vena cava is called the ___ ___.
plica venae cavae
The hilus is the area where ___ and ___ enter and exit the lung.
bronchi, blood vessels
When removing the lungs, be careful to make cuts far enough away from the heart to avoid compromising the ___ and ___ nerves.
phrenic, vagus
The skin of the ventral abdominal wall, caudal to the xiphoid process, is VERY ___; make this a shallow incision.
thin
The two pleural cavities are separate and ___; they essentially only represent potential spaces.
closed
In the transverse section of the thoracic cavity, the ___ cavity is identified as the space surrounding the lungs.
pleural
The ___ cavity surrounds the heart and is bordered by serous membranes.
pericardial
The right lung consists of ___, ___, ___, and ___ lobes.
cranial, middle, caudal, accessory
The goal is to elevate the sternum ventrally without tearing the attached ___.
mediastinum
Define what is meant by the ___ and explain its relationship to serous cavities of the thoracic cavity.
mediastinum
The epaxial muscles are located dorsal to the ___ processes of the vertebrae.
transverse
Make a mid-ventral incision through the skin from the mid cervical region to the ___.
umbilicus
In the thoracic cavity, the structures to identify include the heart, lungs, pulmonary arteries, ___, and azygos vein.
aorta
During a surgical approach to the thoracic body wall, one should visualize the muscular layers from ___ to ___.
superficial, deep
The surgical approach discussed is to the left ___ intercostal space.
4th
After dissection, cadavers should be wrapped in soaked sheets and placed back in the ___ storage bag.
plastic
When reflecting the skin of the thorax and neck, it is important to keep the cutaneous muscles, such as the ___ muscle, attached to the skin.
cutaneous trunci
The boundaries of the ___ can be defined where the costal cartilages of the 10th, 11th, and 12th ribs join.
costal arch
The left lung has ___ lobes compared to the right lung, which has ___ lobes.
two, three
The mediastinal parietal pleura forms the walls of the ___.
mediastinum
The prominent features of individual thoracic vertebrae include the body, transverse processes, spinous processes, and ___ processes.
articular
The left lung has a cranial lobe divided into ___ and ___ parts.
cranial, caudal
Ribs 1-8 are called 'true ribs' because they connect directly to the sternum via ___ cartilage.
costal
The pulmonary ligament is a structure that connects the ___ to the ___ of the thoracic cavity.
lung, mediastinum
Before removing the skin, examine superficial structures that provide useful anatomical landmarks for ___ structures.
deeper
To remove the left lung, you must carefully incise the ___ ligament.
pulmonary
The ___ pleura is the serous membrane that intimately covers the surface of each lung.
visceral (pulmonary)
Make a transverse cut at the caudal extent of the sternum to free the ___ edge of the sternal flap.
caudal
Compare and contrast the serous membranes associated with the thoracic body wall and lungs, with those associated with the ___ and the mediastinum.
heart
On a CT scan, the heart is located between the ___ and the ___ in the thoracic cavity.
lungs, diaphragm
Mammae are described as ___, abdominal, or inguinal.
thoracic
The ___ parietal pleura covers the thoracic surface of the diaphragm.
diaphragmatic
Demonstrate the ___ membranes of the thoracic cavity and the relationship of thoracic viscera to them.
serous
The two white nerves identified in the mediastinum are the ___ nerve and the ___ nerve.
vagus, phrenic
The muscles of the thoracic body wall can be divided into three functional groups: epaxial, extrinsic forelimb muscles, and muscles of ___.
ventilation
The ___ pleura lines the internal surface of the thoracic cavity.
parietal
The mediastinum is defined as the two mediastinal parietal pleurae and the compartment between them that contains the majority of the ___ viscera.
thoracic
Explain the relative position of the cranial vena cava, caudal vena cava, azygous vein, phrenic nerves, esophagus, heart, trachea, and aorta within the ___.
mediastinum
Extrinsic forelimb muscles primarily attach to either the ___ or the ___ of the forelimb.
scapula, humerus
Make a transverse skin incision from the umbilicus to the ___ on both sides.
dorsal midline
The latissimus dorsi, superficial pectoral, and deep pectoral muscles are key muscles to observe in the thoracic body wall dissection, along with the ___ muscle.
serratus ventralis
The only content of the pleural cavities is a small amount of serous fluid, which provides ___ to reduce friction during respiration.
lubrication
What is the lobation pattern of the left lung in dogs?
The left lung has a cranial lobe (divided into cranial and caudal parts) and a caudal lobe.
What is the pleural cavity?
The pleural cavity is the space between the layers of pleura surrounding each lung, containing pleural fluid that reduces friction during breathing.
What are the layers of serous membranes?
The layers of serous membranes include the parietal pleura (lining the thoracic cavity) and visceral pleura (covering the lungs), as well as the parietal pericardium and visceral pericardium surrounding the heart.
What is the umbilicus?
The umbilicus is a prominent landmark on the ventral surface that is useful for abdominal surgery.
What is the cardiac notch?
The cardiac notch is a space in the right lung at the fourth and fifth intercostal spaces that accommodates the position of the right ventricle of the heart.
What is the Diaphragmatic parietal pleura?
The part of the parietal pleura that covers the thoracic surface of the diaphragm.
What is the rectus abdominis muscle?
A muscle located in the anterior abdominal wall that extends from the pubic symphysis to the xiphoid process and costal cartilages, involved in flexing the lumbar spine.
What is the function of costal foveae?
Costal foveae are unique to thoracic vertebrae and serve as sites for articulations with the heads of ribs.
What is the costal arch?
The curved structure formed by the costal cartilages of the ribs that connects to the sternum, providing support to the thoracic cavity.
What is a floating rib?
A floating rib is rib 13, which does not attach to the sternum.
What is the pericardial cavity?
The pericardial cavity is the space between the layers of the pericardium surrounding the heart, containing pericardial fluid that allows for smooth heart movement.
What is the role of the serratus ventralis muscle?
The serratus ventralis muscle is an extrinsic limb muscle that, along with others, forms a muscular sling to support the trunk.
What are intercostal muscles?
Muscles located between the ribs that assist in the expansion and contraction of the thoracic cavity during respiration.
What is the function of epaxial muscles?
Epaxial muscles are dorsal to the transverse processes of the vertebrae and function to extend the vertebral column and support weight.
What is the transversus abdominis muscle?
The deepest muscle of the abdominal wall that lies beneath the rectus abdominis and external abdominal oblique, playing a crucial role in stabilizing the core and maintaining intra-abdominal pressure.
What is the azygous vein?
A vein that drains blood from the thoracic wall and empties into the superior vena cava, located in the mediastinum.
What are the lobes of the right lung?
The right lung consists of three lobes: the cranial lobe, the middle lobe, and the caudal lobe, along with an accessory lobe.
What is the significance of the cranial border of the diaphragm?
The cranial border of the diaphragm is located in relation to the costal arch, and an arrow passing between these locations could hit both thoracic and abdominal viscera.
What is the Parietal pleura?
The serous membrane that lines the internal surface of the thoracic cavity.
What are segmental cutaneous nerves?
Segmental cutaneous nerves are nerves that supply tissues of the thoracic body wall and exhibit a segmental nature.
What is the hilus?
The region where blood vessels and nerves enter and exit the lung, crucial for lung stability.
What is the cutaneous trunci muscle?
The cutaneous trunci muscle is a cutaneous muscle of the neck, thorax, and abdomen that can remain attached to the skin during dissection.
What is the thoracolumbar fascia?
The thoracolumbar fascia is a connective tissue structure that serves as an important landmark in the dissection of the thoracic cavity, providing attachment points for muscles of the back and abdomen.
What is the plica venae cavae?
The plica venae cavae is a fold of pleura that covers the inferior vena cava as it passes through the thorax, helping to stabilize the position of the vena cava.
How do you identify the heart on a CT scan of the thoracic cavity?
The heart appears as a central structure with distinct chambers and is located between the lungs, surrounded by the pericardium.
What is the costal arch?
The costal arch is formed by the costal cartilages of the 10th, 11th, and 12th ribs joining before articulating with the sternum.
What is the Mediastinum?
A conceptual abstraction defined as the two mediastinal parietal pleurae and the compartment between them that contains the majority of the thoracic viscera.
What is the thymus?
A gland located in the mediastinum, important for immune system development, particularly in younger animals.
What are serous membranes?
Serous membranes are thin layers of tissue that line the thoracic cavity and cover the organs within it, providing lubrication and reducing friction during movement.
What is the role of the diaphragm in the thoracic cavity?
The diaphragm forms the caudal boundary of the thoracic cavity and has bony attachments that define its position.
What lobes are present in the right lung of dogs?
The right lung has cranial, middle, caudal, and accessory lobes.
What should be done to the lungs after removal?
The lungs should be moistened and kept in a small plastic bag for easy access in subsequent laboratories.
What is the pericardium?
The pericardium is a double-walled sac that contains the heart and the roots of the great vessels. It provides protection and reduces friction during heartbeats.
What is the caudal vena cava?
A large vein that carries deoxygenated blood from the lower body to the heart, passing through the mediastinum caudally.
What is the thoracic inlet?
The thoracic inlet is the cranial extent of the thoracic cavity, marked by specific bony landmarks.
What is the mediastinum?
The mediastinum is the central compartment of the thoracic cavity, located between the lungs, containing the heart, great vessels, trachea, esophagus, and other structures.
What is the Visceral (pulmonary) pleura?
The serous membrane that intimately covers the surface of each lung.
What is the Mediastinal parietal pleura?
The part of the parietal pleura that forms the walls of the mediastinum, the central compartment between the two pleural cavities.
What is the axilla?
The axilla, commonly known as the armpit, is the area beneath the shoulder joint that contains important structures such as blood vessels and nerves, serving as a landmark in thoracic dissection.
What is the sympathetic trunk?
The sympathetic trunk is a bundle of nerve fibers that runs along each side of the vertebral column, playing a crucial role in the autonomic nervous system and serving as a landmark in thoracic dissection.
What are the lobes of the left lung?
The left lung consists of two lobes: the cranial lobe (which is further divided into the cranial and caudal parts) and the caudal lobe.
What is the root of the lung?
The root of the lung refers to the collection of structures entering and exiting the lung.
What are the two important nerves associated with the lung's mediastinum?
The two important nerves are the vagus nerve (dorsal to the root of the lung) and the phrenic nerve (ventral to the root of the lung).
What are extrinsic forelimb muscles?
Extrinsic forelimb muscles extend from the axial skeleton to a bone of the forelimb, primarily moving the limb relative to the body or vice versa.
What are thoracic vertebrae?
Thoracic vertebrae are the vertebrae located in the thoracic region of the spine, characterized by features such as costal foveae for rib articulation.
What are true ribs?
True ribs are ribs 1-8 that connect directly to the sternum via costal cartilage.
What is the purpose of cutting the cranial aponeurosis of the rectus abdominis?
To reflect the muscle caudally and expose the length of the costal arch that it normally covers.
What are mammillary processes?
Mammillary processes are features common to all vertebrae, except caudal vertebrae, serving as attachment surfaces for muscles that maintain extension at the vertebral joints.
What is the Costal parietal pleura?
The part of the parietal pleura that lines the lateral thoracic walls along the ribs.
Which muscles are included in the study of the thoracic body wall?
The muscles included are the latissimus dorsi, superficial pectoral, deep pectoral, and serratus ventralis.
What is the brachial plexus?
The brachial plexus is a network of nerves that innervates the muscles and skin of the shoulder, arm, and hand, and is relevant as a landmark during thoracic cavity dissection.
What is the costal arch?
The costal arch is the curved structure formed by the cartilages of the lower ribs, which serves as an important landmark in the anatomy of the thoracic cavity.
What is the esophagus?
A muscular tube that connects the throat to the stomach, located within the mediastinum.
How do you orient an isolated lung to determine if it is right or left?
To orient an isolated lung, identify the cranial and caudal lobes; the left lung has two lobes (cranial and caudal), while the right lung has three lobes (cranial, middle, and caudal).
What is the plica venae cavae?
The serous membrane fold of mediastinal pleura surrounding the caudal vena cava.
What are mammae?
Mammae are the mammary glands that may vary in number, averaging ten in the dog, and are described as thoracic, abdominal, or inguinal.
What should be noted about skin incisions in the ventral abdominal wall?
The skin of the ventral abdominal wall, caudal to the xiphoid process, is very thin, requiring shallow incisions.
What is the significance of the pleural cavities?
The two pleural cavities are separate and closed potential spaces that normally contain a small amount of serous fluid for lubrication during respiration.
What is rib 13 known for?
Rib 13 is a 'free floating' rib, meaning it does not articulate with the costal arch and is typically much shorter than rib 12.
What is the aorta?
The largest artery in the body, carrying oxygenated blood from the heart to the rest of the body, located in the mediastinum.
What are the three functional groups of muscles of the thoracic body wall?
The three functional groups are epaxial muscles, extrinsic forelimb muscles, and muscles of ventilation.
What is the pulmonary ligament?
The pulmonary ligament is a fold of pleura that extends from the hilum of the lung to the mediastinum, providing support and stability to the lung.
What is the hilus?
The hilus is the region on the lung where the bronchi, blood vessels, and nerves enter and exit, serving as the main gateway for lung function.
What are the costal and mediastinal parietal pleura?
The costal pleura lines the inner surface of the thoracic wall, while the mediastinal pleura covers the mediastinum, both providing a smooth surface for lung expansion.
What is the trachea?
The windpipe that connects the larynx to the bronchi, located in the mediastinum.
What is the cranial vena cava?
A large vein that carries deoxygenated blood from the upper body to the heart, passing through the mediastinum cranially.
What is an aponeurosis?
An aponeurosis is a flat, sheet-like fibrous tissue that connects muscles to the parts they move, serving as a significant anatomical landmark in thoracic dissection.
What are false ribs?
False ribs are ribs 9-12 that attach indirectly to the sternum through the costal arch.
What is the mediastinum?
The mediastinum is the central compartment of the thoracic cavity that contains the heart, great vessels, trachea, esophagus, and other structures, serving as a key area of study in thoracic anatomy.
What is the vagus nerve?
A nerve that innervates various organs and follows a course similar to the phrenic nerve but passes dorsal to the hilus of the lung.
What are phrenic nerves?
Nerves that innervate the diaphragm, running from the thoracic inlet to the diaphragm, passing ventral to the hilus of the lung.
What is the heart?
The organ that pumps blood throughout the body, located in the mediastinum.
What is the significance of intervertebral discs?
Intervertebral discs are positioned between adjacent vertebral bodies and allow for articulation and flexibility in the vertebral column.
What is the pulmonary ligament?
A double fold of connecting pleura that stabilizes the caudal lobe of the lung, running between the lung and the mediastinum.
