2.4 - Thoracic wall

thorax

The cranial trunk between the neck and abdomen

Thoracic cavity

Space protected by the rib cage and limited caudally by the diaphragm

Rib cage

Bony structure that protects the thoracic cavity and part of the abdominal cavity

Ribs, thoracic vertebrae, and sternum

What 3 structures make up the entirety of the rib cage

36 ribs

How many ribs does a horse have?

26 ribs

How many ribs does a dog have?

26 ribs

How many ribs does a goat have?

28-30 ribs

How many ribs does a pig have?

Cartilage of manubrium

A

Sternebrae

B

Xiphoid cartilage

C

Tubercle

A

Head

B

Neck

C

Body

D

Costal cartilage

E

Intervertebral joints

Identify the joint of the rib cage - 1

Costovertebral joints

Identify the joint of the rib cage - 2

Costochondral joints

Identify the joint of the rib cage -3

Sternocostal joints

Identify the joint of the rib cage -4

Sternal joints

Identify the joint of the rib cage -5

Intercostal joints

Identify the joint of the rib cage -6

Supraspinous ligament

Identify the intervertebral ligaments - 1

Interspinous ligament

Identify the intervertebral ligaments - 2

Dorsal intervertebral ligament

Identify the intervertebral ligaments - 3

Ventral intervertebral ligament

Identify the intervertebral ligaments - 4

Ligament of costal tubercle

Identify the costovertebral ligament - 6

superficial radiate costal ligament

Identify the costovertebral ligament - 7

Radiate ligament

Identify the costovertebral ligament - 8

Costotransverse ligament

Identify the costovertebral ligament - 9

Lateral costotransverse ligament

Identify the costovertebral ligament - 10

Periosteum and perichondrium

In the costochondral joints, what part of the rib and which part of the costal cartilage attach to one another

Costochondral joint

1

Sternal rib

2

Asternal ribs

3

Floating rib

4

Radiate sternocostal ligament

Identify the red box

Sternal ligament

Identify

Calcifies

What happens to the sternal cartilages to make it one bony piece

True

T/F - species to species, the contribution of the superficial muscles to the thoracic wall varies

Deep

Is the serratus ventralis deep or superficial to the latissimus dorsi

Latissimus dorsi

External abdominal olique

2

Latissimus dorsi

1

Serratus ventralis

1

Levatores costarum

Identify the muscle

External intercostals

Identify the muscle

Caudal borders of the ribs

Origin of external intercostals

Cranial borders and lateral surfaces of the ribs

Insertion of external intercostals

Dorsal Rami, intercostal nerves

What innervates the levatores costarum

Intercostal nerves

What innervates the external intercostals

Internal intercostals

Identify the muscle

Cranial border of the ribs

Origin of internal intercostals

Caudal borders of next ribs

Insertion of internal intercostals

Intercostal nerves

Innervation of internal intercostals

to pull ribs caudally during expiration

Action of internal intercostals

Retractor costae

Identify

Transversus thoracis

Identify

Rectus thoracis

Identify

Pectoralis superficialis

Identify

Pectoralis profundus

Identify

Diaphragm

Broad unpaired muscle that divides the thoracic and abdominal cavities

Costal, sternal,and lumbar regions of the sternum and ribs

Origin of the diaphragm

Central tendon

Insertion of diaphragm

Phrenic nerve

innervation of diaphragm

Increase the volume of thoracic cavity during respiration

action of diaphragm

Central tendon

A

Costal region

B

Sternal region

C

Lumbar region

D

Aortic hiatus

opening in the diaphragm allowing the aorta, azygos vein, and thoracic duct to pass from the thorax to the abdomen

Esophageal hiatus

where the esophagus passes through the diaphragm

Foramen vena cavae

Allows the caudal vena cava to pass from the abdomen to the thorax

Aortic hiatus

A

Esophageal hiatus

B

Foramen vena cavae

C

dorsal intercostal branches off the aorta

What is the dorsal blood supply to the thoracic wall

Ventral intercostal branches off the internal thoracic

What is the ventral blood supply to the thoracic wall

Internal thoracic vein

What does thoracic wall blood drain to ventrally

azygous vein

Where does thoracic wall blood drain to dorsally

Ventral rami

What innervates the lateral thoracic wall and the cutaneous innervation

Intercostal artery, vein, and nerve

Artery, vein, and nerve found caudal to the ribs and cranial to the intercostal space

Intercostal collateral artery, vein, and nerve

Artery, vein, and nerve found cranial to the ribs and caudal to the intercostal space

Thoracotomy

surgical incision into the chest cavity

Thoracic lavage

Uses saline to clear out debris or infection from the chest cavity