Practical topic 18

Question 1

Give the muscles of the pelvic girdle

Answer 1

1. M. psoas minor
2. M. iliopsoas

• M. psoas major
• M. Iliacus medialis
• M. iliacus lateralis

3. M. quadratus lumborumps

Question 2

M. Psoas minor

Answer 2

Origin: Corpus of the last few thoracic vertebrae and L1-5

Insertion: Linea arcurata of Os ilium, near eminentia iliopubica (iliac?)

Action:

• If the vertebral column is fixed: draws pelvis into a deeper position.
• When the pelvis is fixed: arches lumbar region and flexes vertebral column.

Innervation: N. Femoralis

Blood supply: A. iliolumbalis

Question 3

M. Psoas major

Answer 3

Origin: Ventrally from corpus and processus transversus of lumbar vertebrae

Insertion:

• Trochanter minor of femur (medially) between m. Rectus femoris and m. Pectineus.
  
  • Together with m. Iliacus

Action:

• Draws pelvic limb forward by flexing the hip joint and turning the stifle outwards.
• When femur is fixed: stabilizes and arches it dorsally limb drawn backwards - pulls trunk caudally.

Innervation: N. Femoralis

Blood supply: A. iliolumbalis

Question 4

M. Iliacus

Answer 4

Origin: Arising between linea arcurata and lateral border of iliac bone (sacroiliac joint)

Insertion:

• Trochanter minor of femur (medially) between m. Rectus femoris and m. Pectineus.
  
  • Together with m. Psoas major.

Action: Enforcement of the sacroiliac joint.

Innervation: N. Femoralis

Blood supply: A. iliolumbalis

Question 5

M. Quadratus lumbarum

Answer 5

Origin:

• Th11-13 vertebra, ventrally.
• Last two ribs
• Processus transversus of lumbar vertebra

Insertion: Ala ossis ilii, medial surface (between articular surface and spina iliaca cranialis ventralis of tuber coxae).

Action: Fixation and dorsal flexion of vertebral column.

Innervation: N. femoralis

Blood supply: A. iliolumbalis

Question 6

Spinal nerves

Answer 6

Dorsal and ventral ramus joins as they leave the spinal column, and divides again after exiting through foramen intervertebrale

• Each dorsal branch: divides into medial and lateral branch:
  
  • R. medialis: innervate muscles of the back
  • R. lateralis: innervates the skin over the “rump” region
• Each ventral branch will interconnect → forms the plexus

Question 7

Plexus lumbalis:

How many lumbar nerves does the dog have?

Answer 7

7

The number of lumbar nerve corresponds with the number of lumbar vertebrae

Question 8

Which nerves does the plexus lumbalis consists of?

Answer 8

1. N. iliohypogastricus cranialis
2. N. iliohypogastricus caudalis
3. N. ileoinguinalis
4. N. cutaneus femoris lateralis
5. N. femoris (thickest)
   
   • N. saphena (given off in canalis femoralis)
6. N. obturatorius

Question 9

N. iliohypogastricus

1. Arises from
2. Divides into

Answer 9

1. L1 and L2
2. Divides into:
   
   • Medial branch
     
     • Passes through the inguinal region
   • Lateral branch:
     
     • Innervates the skin of the abdominal wall

In Ca and Fe divided into:

• N. iliohypogastricus cranialis
• N. iliohypogastricus caudalis

Question 10

N. ilioinguinalis

1. Arises from
2. Divides into

Answer 10

1. L3
2. Follow similar path to n. iliohypogastricus

Question 11

N. genitofemoralis

1. Arises from
2. Where does it rum
3. Innervates

Answer 11

1. L3 and L4
2. Runs caudally between the lumbar muscles and exit through the canalis inguinalis
3. Innervates:
   
   • Medial muscles of the thigh
   • Vulva / scrotum
   • prepuce
   • Autonomous fibers to ensure milk “let-down”

Question 12

N. cutaneus femoralis lateralis

1. Arises from
2. Innervates

Answer 12

1. L4
2. Innervates:
   
   • Skin over the distal thigh
   • Articulatio genus (stifle joint)

Question 13

N. femoralis

1. Where does it go
2. Branches

Answer 13

1. Courses through mm. psoas. Along with a. iliaca externa and v. iliaca communis
2. Branches:
   
   • N. saphena
     
     • Branch to m. sartorius, supplies skin over medial aspect of the limb from stifle → metatarsus
   • Muscle branches to m. quadriceps femoris

Question 14

N. obturatorius

Where does it run?

Answer 14

Medial aspect of the shaft of the ilium

→ foramen obturatorium

→ mm. adductors

Question 15

Truncus lumbosacralis

1. Where does it leave pelvis?
2. Give the branches

Answer 15

1. Leaves the pelvis through the greater sciatic formaen
2. Detach 3 branches:
   
   • N. gluteus cranialis
   • N. gluteus caudalis
   • N. ischiadicus

Question 16

Lubosacral plexus

Removed sublumbar musculature and terminal branches of the aorta

Answer 16

• → Ventral branches of spinal nerves

1. L4
2. S1
3. S3
4. N. femoralis cutanei lateralis
5. N. femoralis
6. N. saphena
7. n. obturatorium
8. Lumbosacral trunk
   
   • Formed by L6, L7 and S1 ventral branches
   • Can be seen entering the greater ischiadic notch
9. Pelvic nerve
10. Femoral vessels
11. A. glutea caudalis