THRC.22

Question 1

Give the components of the sacral plexus

Answer 1

• Sciatic plexus
  
  • Cranial gluteal nerve
  • Caudal gluteal nerve
  • Caudal cutaneous nerve of femur
  • Pudendal nerve
  • Caudal rectal nerves

Question 2

Answer 2

Cranial gluteal nerve

Question 3

Answer 3

Caudal rectal nerve

Question 4

Answer 4

Caudal gluteal nerve

Question 5

Answer 5

Ischiadic/sciatic nerve

Question 6

Answer 6

Pudendal nerve

Question 7

Answer 7

Caudal cutaneous femoral nerve

Question 8

Answer 8

Tibial nerve

Question 9

Answer 9

Common fibular nerve

Question 10

Answer 10

Caudal cutaneous sural nerve

Question 11

Answer 11

Tibial nerve

Question 12

The sacral plexus is formed by the…

Answer 12

Ventral branches of the cranial sacral nerves

Question 13

Give the path of the sciatic plexus

Answer 13

• Branches off the nerves of the sacral plexus
• Continues down the limb as the sciatic nerve

Question 14

Give the path of the cranial gluteal nerve

Answer 14

• Passes over the greater ischiatic notch
• Innervates:
  
  • Middle/deep gluteal muscles
  • Tensor fascia lata
  • Piriform muscles

Question 15

Give the path of the caudal gluteal nerve

Answer 15

• From caudal sciatic plexus
• Innervates:
  
  • Biceps femoris
  • Gluteobiceps (Su/Ru)
  • Superficial gluteal muscle
  • Hamstring

Question 16

Give the path of the caudal femoral cutaneous nerve

Answer 16

• Passes caudally towards tuber ischiadicum
• Detaches motor branches:
  
  • Semitendinosus
• Branches off caudal clunial nerves

Question 17

Give the path of the pudendal nerve

Answer 17

• S₃
• Parasympathetic fibres
• Communicating branches → caudal femoral cutaneous nerve
• Innervates muscles/organs in the perineal + anal region
• Motor innervation:
  
  • Ischiocavernosus
  • Bulbospongiosus
  • Retractor penis
  • Coccygeal
  • Levator ani
• Terminating in penis/vulva

Question 18

Give the path of the caudal rectal nerves

Answer 18

• May rise from the pudendal nerve
• Innervate:
  
  • Caudal rectum
  • External anal sphincter
  • Skin around the anus

Question 19

Sciatic nerve

Answer 19

• Leaves pelvis through the greater sciatic foramen
• Passes over the sacrotuberous ligament
• Motor innervation:
  
  • Deep gluteal
  • Internal obturator
  • Quadriceps femoris
  • Gemelli
• Sensory innervation:
  
  • Hip joint
• Terminates by dividing:
  
  • Tibial nerve
  • Common fibular nerve