L30: Abdominal Wall

Question 1

4 features of Sacrum. Also, what is exclusive about the dog’s sacrum?

Answer 1

1. Pelvic area
2. ~3-5 fused vertebrae
3. Articulate with ilium at SI joint (S1 sometimes also S2)
4. Rest of vertebrae form roof of pelvic cavity

Dog: 3 vertebrae form one block

Question 2

What the auricular surface articulate with?

Answer 2

Ilium on either side

Question 3

What structure does the hamstring muscle attach to?

Answer 3

Tuber Ischiarum (ischium)

Question 4

Where is the structure where umbilical cord attaches?

Answer 4

Umbilicus

Question 5

What is the name of the surgical white line entering abdomen?

Answer 5

Linea alba

Question 6

What are mammary glands? (2)

Answer 6

• Modified, much enlarged sweat glands

- Evolutionary modified to produce colostrum

Question 7

What is colostrum?

Answer 7

• Modified milk produced immediately after parturition

- Has a role in the passive transfer of immunity to the newborn

Question 8

What does each mammary gland have a compound of?

Answer 8

• Each gland is a compound tubuloalveolar gland that consists of secretory units grouped into lobules defined by intervening connective tissue septa

Question 9

What are features of supernumerary teats?

Answer 9

• May be independent or attached to other, better developed glands
• May interfere with milking
• Often removed from the udders of cows and goats
• NOT FUNCTIONAL*

Question 10

What is the diaphragm a muscle of?

Answer 10

Abdomen

Question 11

What is the function of the diaphragm?

Answer 11

Openings permit passage of blood and lymphatic vessels, esophagus and nerves between the abdomen and the thorax

Question 12

The diaphragm consists of 3 major apertures. What are they and what do each permit passage of?

Answer 12

1. Caval foramen
   - Caudal vena cava
2. Esophageal hiatus
   - Esophagus
   - Vagal trunks
3. Aortic hiatus
   - Aorta
   - Azygous Vein
   - Thoracic duct

Question 13

Two groups of muscles of the abdominal wall- describe what specific muscles are in each group. What are they innervated by?

Answer 13

1. Ventrolateral
   - External abdominal oblique, Internal abdominal
   oblique, transversus abdominis, rectus abdominus
2. Dorsal (sublumbar)
   - Psoas minor, psoas major, Quadratus lumborum

–> Both innervated by ventral rami

Question 14

In regard to the muscles of abdominal wall, what is the function of all four of the ventrolateral muscles?

Answer 14

• Compression of the abdominal viscera (abdominal press), aids in such vital functions as expiration, urination, defecation, and parturition

Question 15

In regard to the muscles of abdominal wall, what is the function of specifically the External abdominal oblique, and rectus abdominus?

Answer 15

• Flexion of the vertebral column when fellow muscles contract; lateral bending of the vertebral column (unilateral)

Question 16

What is the inguinal ligament?

Answer 16

Free edge of the external abdominal obliques

Question 17

What is the superficial inguinal ring associated with and what is its function? (3)

Answer 17

• Associated with the inguinal ligament
• Opening between the abdominal and pelvic tendons of the external abdominal oblique
• Exit from the canal

Question 18

What is the cremaster muscle?

Answer 18

A muscle slip detached from the internal oblique that passes onto the spermatic cord

Question 19

What is the transversus abdominis?

Answer 19

The deepest muscle of the lateral abdominal wall (flank)

Question 20

What is the common insertion for the abdominal muscles and the linea alba?

Answer 20

Prepubic tendon

Question 21

What is the transversalis fascia?

Answer 21

A lining of fascia deep to the transversus abdominis that contacts the peritoneum of the abdominal cavity

Question 22

In the rectus sheath of the abdominal wall, why is there a progressively weaker body wall caudal to the umbilicus and nearer to the pubis?

Answer 22

Caudally the aponeuroses of the internal abdominal oblique and transversus abdominis change their relative position to the rectus abdominis

Question 23

What is the prepubic tendon and happens to this in some pregnant females?

Answer 23

• Common insertion for the abdominal muscles and the linea alba
• Sometimes ruptures in pregnant females during late pregnancy from painful edema in front of the udder

Question 24

What is the deep inguinal ring? (3)

Answer 24

• A boundary and not a distinct anatomical structure
• Lies along the free caudal edge of the internal oblique muscle
• Slit-like
• Abdominal entrance

Question 25

What is the inguinal CANAL? Function?

Answer 25

A natural passageway from the abdominal cavity out to the abdominal wall - Function: Transmits the testis in males during development

Question 26

Inguinal canal: Males vs both Male & Female (3)

Answer 26

Males only: Contains the spermatic cord and associated structures Both genders transmits: - External pudendal artery and usually vein - Efferent vessels from the superficial inguinal lymph nodes - Genitofemoral nerve

Question 27

What is an abdominal hernia?

Answer 27

A displacement and protrusion of part of an organ through the walls of the body cavity

Question 28

Two possible causes of abdominal hernia?

Answer 28

Can be congenital or acquired (trauma)

Question 29

2 main types of abdominal hernias?

Answer 29

1. Umbilical- abdominal contents protrude into the overlying subcutaneous fascia 2. Inguinal- abdominal contents pass through the inguinal canal and my project into the scrotum in males

Question 30

What innervates the abdominal wall? Explain.

Answer 30

Lumbar ventral rami: nerves pass through the transversus abdominis close to the tip of the transverse processes and then run deep to the internal oblique toward the ventral abdominal wall

Question 31

What do the lateral and ventral cutaneous branches supply?

Answer 31

Integument

Question 32

What are the nerves associated with the abdominal wall? *

Answer 32

1. Last intercostal n 2. Costoa-abdominal n. 3. Iliohypogastric* 4. Ilioinguinal n. * 5. Genitofemoral n.*

Question 33

In the Iliohypogastric, ilioinguinal, and genitofemoral n., where is the nerve located in a) species with 6 lumbar nerves, & b) speices with 7?

Answer 33

``` - Iliohypogastric* L1// L1 Cranial, L2 Caudal - Ilioinguinal n. * L2// L3 - Genitofemoral n.* L3-L4// L3-L4 ```

Question 34

What are the muscles of the dorsal abdominal wall? What is the action of each?

Answer 34

1. Psoas major- Flex hip joint, draws pelvis limb forward 2. Psoas minor- Flex the lumbar vertebral column 3. Quadratus lumborum- Stabilize lumbar vertebral column; assist in lateral bending

Question 35

What is the blood supply of the abdominal wall? How is the blood supply split in goats?

Answer 35

Abdominal aorta; | In goats the aorta splits into common iliac aa. which split into the external and internal iliac aa.