Lecture 8: Inguinal canal

Question 1

Review: What are the layers of the abdominal wall?

Answer 1

• Skin
• Fatty superficial fascia (campers fascia)
• Membranous superficial fascia (scarpa’s fascia)
• External oblique
• Internal oblique
• Transverse abdominus
• Transversalis fascia
• Parietal peritoneum

Question 2

What are the key pelvic ligaments?

Answer 2

Question 3

What is the inguinal canal?

Answer 3

• Oblique passage through lower part of abdomial wall
• About 4cm long
• Extends from deep inguinal ring to superficial ingunial ring

Question 4

What does is carry in males and females?

Answer 4

• Males: Spermatic cord (+ ilioinguinal nerve)
• Females: Round ligament of uterus from pelvis to labia majora (+ ilioinguinal nerve)

Question 5

What is the superficial inguinal ring and what are its features?

Answer 5

• Triangular defect in aponeurosis of the external oblique
• Superio-lateral to pubic tubercle
• Medial border is medial crus
• Lateral border is lateral crus
• Gives rise to the external spermatic fasica

Question 6

What is the deep inguinal ring and what are its features?

Answer 6

• Opening in transversalis fascia
• Halfway between ASIS and pubic symphysis - mid inguinal point
  
  • ​lateral to inferior epigastic artery
• about 1.5-2 cm above inguinal ligament
• GIves rise to internal spermatic fascia or round ligament fasica in woman

Question 7

How does transversus abdominus contribute to the borders of the inguinal canal?

Answer 7

• Forms part of the superior wall
• (Once fused with internal oblique) medial conjoint tendon forms posterior wall

Question 8

How does the internal oblique muscle contribute to the borders of the inguinal canal?

Answer 8

• lateral 1/3 forms part of the anterior wall
• Contributes to the roof
• (Once fused with trans. abdom) medial conjoint tendon forms posterior wall

Question 9

What is the conjoint tendon?

Answer 9

• The fusion of the internal oblique and transverse abdominus tendons that wrap over and around the inguinal canal
• It attaches to the pubic crest

Question 10

How does the external oblique contribute to the borders of the inguinal canal?

Answer 10

• Forms part of the anterior wall

Question 11

Draw a schematic of the inguinal canal

Answer 11

Question 12

What is hesselbach’s triangle?

Answer 12

• Weakening in the abdominal wall through which direct hernias occur
• Triangle made form the inguinal ligament, lateral border of rectus abominus and inferior epigastric arteries

Question 13

What are the layers of the spermatic cord?

Answer 13

• Internal spermatic fascia (from transversalis fascia)
• Cremaster muscle (from int. oblique)
• External spermatic fascia (from ext. oblique)

Question 14

What is the tunica vaginalis?

Answer 14

• closed of sac that is a reminant of the processus vaginalis which is the perioteneal diverticulum through which the spermatic cord arises

Question 15

What are the contents of the spermatic cord?

Answer 15

• 3 arteries:
  
  • testicular from L2
  • Artery of Vans deferens
  • Cremasteric artery
• 3 nerves
  
  • Genital branch of the genitofemoral nerve
  • Sympathetic nerve from testicular plexus
  • ilioinguinal nerve (doesnt actually travell in cord)
• 3 other structures:
  
  • Vans deferens
  • Lymphatics
  • Tunica vaginalis
• 1 venous plexus:
  
  • pampiniform plexus

Question 16

What does the testicular artery supply?

Answer 16

• Testes
• Epidiymides

Question 17

What is the vans deferens?

Answer 17

• Muscular duct that transports spermatozoa from epididymis to the urethra

Question 18

What is the purpose of the pampiniform plexus?

Answer 18

• Temp regulation

Question 19

What does the genital branch of the genitofemoral nerve supply?

Answer 19

• cremaster muscle and skin of scrotum

Question 20

Answer 20

good work cunt

Question 21

What is testicular torsion?

Answer 21

• When the spermatic cord twists round cutting of blood supply to the testes
• very painful
  
  • also reffered to the lower abdomen
• Will also caused decreased/absent cremasteric reflex, nausea/vomiting, redness

Question 22

What is the cremasteric reflex?

Answer 22

• Normal reflex:
  
  • Sroke upper inner thigh –> sensory fibres of femoral branch of genitofemoral nerve & ilioinguinal nerve –> back to spine –> stimulates motor fibres of the genital branch of the genitofemoral nerve –> cremaster muscle contracts on same side rasing testis

Question 23

Direct vs indirect inguinal hernias vs femoral hernias?

Answer 23

• Inguinal:
  
  • Superior to inguinal ligament
  • Indirect:
    
    • herniation occurs through DIR
    • lateral to inf. epigastric artery
    • can be seen juveniles
  • Direct:
    
    • Through hesslebach’s triangle
    • medial to inf. epigastric artery
    • males
• Femoral:
  
  • Inferior to inguinal ligament
  • woman
  • occurs through femoral canal