ANATOMY 3.2 (Thorax Intro)

Question 1

Trunk:

Answer 1

-what is left after removing the head, neck, tail and limbs

Question 2

Trunk includes:

Answer 2

-thoracic cavity
-abdominal cavity
-pelvic cavity

Question 3

Who cares about the thorax?

Answer 3

-many systems (cardiovascular, respiratory)
-diagnosis
-treatment

Question 4

Thoracic cavity:

Answer 4

-cranial-most body cavity
-cranial to diaphragm

Question 5

Pleural cavity:

Answer 5

-2 within the thoracic cavity
-left and right: contain the left and right lung

Question 6

Thoracic cage:

Answer 6

-within ribs
-above sternum, below vertebral column

Question 7

Shape and extent of thoracic cavity:

Answer 7

-does NOT correspond to the expectations of the living animal
-looks bigger than it actually is

Question 8

Reasons for thoracic cavity looking bigger than it actually is:

Answer 8

-massive musculature of forelimb
-outlines of back, brisket and coastal arch=thoracic cavity
-shape of diaphragm

Question 9

Shape of diaphragm:

Answer 9

-concave dome within rib cage occupied by abdominal viscera not thoracic viscera

Question 10

Massive musculature

Answer 10

-limb strength is a function of area (x2)
-respiratory is a function of volume (x3)
-60% of body weight borne by forelimbs
-larger animal=larger proportion composed of musculoskeletal tissue

Question 11

Horse/cow vs. dog lung size:

Answer 11

-lungs of dog are relatively massive compared to horse/cow

Question 12

Inspiration:

Answer 12

-diaphragm contracts a pulls lungs downwards
-ribs elevate

Question 13

Ribs:

Answer 13

-basic form: bucket handle
-costo-chondral parts
-costo-chondral junction
-3 articulations
-joint types

Question 14

Cranial ribs shape:

Answer 14

-rigid
-short
-straight

Question 15

Caudal ribs shape:

Answer 15

-more slender and curved

Question 16

Costo-part:

Answer 16

-top portion
-cartilage

Question 17

Chondral-part:

Answer 17

-bottom

Question 18

3 articulations of ribs:

Answer 18

-vertebral
-sternal
-chondral (costal arch)

Question 19

Vertebral articulations:

Answer 19

-costo-vertebral
-costo-transverse

Question 20

Costo-vertebral:

Answer 20

-ball and socket
-2 intercapital ligament

Question 21

Costo-transverse:

Answer 21

-sliding
-8 costo-transverse ligament
-6 dorsal longitudinal ligament

Question 22

Rib types

Answer 22

-short, long, “true”, “false”, “floating”
-cylindrical vs. flattened
-curved or not curved

Question 23

Sternebrae:

Answer 23

-cylindrical vs. flattened vs. “keel’ like
-inter-sternal joints
-costo-sternal joints
-interchondral joints

Question 24

Inter-sternal joints:

Answer 24

-synchondroses
-later ossify

Question 25

Costo-sternal joints:

Answer 25

-synovial
-pivot type

Question 26

Interchondral joints:

Answer 26

-syndesmoses
-elastic

Question 27

Number of thoracic vertebrae:

Answer 27

=number of ribs
-rib number corresponds to vertebra of caudal attachment
-1 sternebra less than number of sternal ribs (includes manubrium and xiphoid)

Question 28

Thoracic vertebra in different species:

Answer 28

-canine: 13
-equine: 18
-ruminant: 13
-porcine: 14-15
-human: 12

Question 29

Sternal rib pairs in different species:

Answer 29

-canine: 9
-equine: 8
-ruminant: 8
-porcine: 7
-human: 7

Question 30

Thoracic girdle:

Answer 30

=synsarcosis

Question 31

Superficial layer of extrinsic muscles of forelimb:

Answer 31

-trapezius
-omotransversarius
-brachiocephalicus
-latissimus dorsi
-superficial pectorals

Question 32

Deep layer of extrinsic muscles of forelimb:

Answer 32

-rhomboideus
-serratus ventralis
-deep pectorals

Question 33

Dog cranial view musles/landmarks:

Answer 33

-brachiocephalicus
-sternocephalicus
-jugular groove
-thoracic inlet

Question 34

Muscles of thoracic wall:

Answer 34

-scalenus
-serratus dorsalis
-intercostals
-rectus thoracis

Question 35

Serratus dorsalis parts/actions:

Answer 35

-cranial: inspiratory action, increases cavity
-caudal: bucket handles go down=expiratory

Question 36

Epaxial muscles:

Answer 36

-above transverse process on either side of vertebral column
1. Transversospinalis system
2. Longissimus system
3. Iliocostalis system

Question 37

Transversospinalis system:

Answer 37

-shorter ones all the way along

Question 38

Longissimus system:

Answer 38

-long one at the caudal end
-not all the way to the cranial end

Question 39

Iliocostalis system:

Answer 39

-3 longer ones

Question 40

Hypaxial muscles:

Answer 40

-flexor muscles of neck or tail

Question 41

Muscles of thoracic and abdominal walls:

Answer 41

-3 analogous layers

Question 42

Abdominal wall 3 muscle layers:

Answer 42

-external oblique
-internal oblique
-transversus abdominis

Question 43

Thoracic wall 3 muscle layers:

Answer 43

-external intercostal
-internal intercostal
-transversus thoracis