Gross Pelvic Bowl, Inguinal Canal, Spermatic Cord and Hernias

Question 1

Define the landmarks that mark the pelvic inlet and the pelvic outlet.

Answer 1

inlet: drawing a line from the superior aspect of the pubic symphysis anteriorly, to the sacral promontory posteriorly
outlet: drawing a line between the inferior aspect of the pubic symphysis anteriorly, and the tip of the coccyx posteriorly

Question 2

Describe the composition and position of the pelvic diaphragm and list its functions

Answer 2

thin muscular sheet that makes the floor of the pelvic cavity

function: maintaining continence - said to be “tonically contracted” support pelvic viscera, resist increased intraabdominal pressure and to maintain urinary and fecal continence

Question 3

Describe the location and boundaries of the perineum

Answer 3

area of the trunk that extends from the pubic symphysis anteriorly to the coccyx posteriorly, laterally bound to the thighs
lies below the pelvic diaphragm and is defined by two pouches (superficial and deep) which contain portions of the male and female genitalia
associated with muscles and neurovascular bundles

Question 4

Describe the origin, course, and termination of the inguinal canal. How do these differ in males vs females?

Answer 4

oblique - 4cm long tunnel - slopes inferiorly and medially through the anterior abdominal wall formed as a result of the migration of the gonads during development

• connects the extraperitoneal space of the abdomen to teh scrotum (men) or labia majora - passageway for the testes and attached spermatic cord or round ligament of the uterus and associated blood vessels, nerves, lymphatics
• larger in men
• beginning = deep inguinal ring
• termination = superficial inguinal ring

Question 5

It is said that the inguinal canal is an “arcade of arches” Explain why

Answer 5

because it is a passageway through the abdominal wall musculature formed by the three flat abdominal muscles
-common site of hernias because of the location - bears the weight of the abdominal viscera when the body is upright

Question 6

Describe where the major weaknesses in the inguinal canal are

Answer 6

1. indirect/lateral inguinal hernia - lateral to the inferior epigastric artery - mostly on the right side (descent of testis takes longer on right side) CONGENITAL
2. medial inguinal hernia - medial to the inferior epigastric artery and passes through Hesselbachs triangle - ACQUIRED - weakness in the posterior wall of the inguinal canal

Question 7

The cremaster muscle is derived from ___________, together with the ___________, and is innervated by the ___________ nerve

Answer 7

fascia of the internal abdominal oblique muscle
middle spermatic fascia
genital branch of the genitofemoral nerve

Question 8

What is the cremaster reflex? Which nerve are involved in the reflex?

Answer 8

cremaster muscle reflexively drawing the testes up into the scrotum when it’s cold (relaxes and testes descend when it’s warm)
genital branch of the genitofemoral nerve
can be elicited by lightly stroking the skin of the inner thigh downwards

Question 9

The spermatic cord has ___________ fascial coverings. List each fascial covering, its origin, and the place where it is first applied to the spermatic cord.

Answer 9

3

1. internal spermatic fascia derived from transversalis fascia at the deep inguinal ring - extends to testes
2. cremaster muscle and middle spermatic fascia derived from the internal abdominal oblique muscle, extends to superior poles of the testes
3. external spermatic fascia derived from external oblique aponeurosis covering the cord

Question 10

What is the conjoint tendon?

Answer 10

combined fibers of the internal abdominal oblique and the transversus abdominis muscles = located immediately posterior to the superficial inguinal ring, strengthening it

Question 11

The gubernaculum is located on the ___________ surface of the developing gonad. In the adult male it becomes the ___________.

Answer 11

inferior
scrotal ligament - attaching the lower pole of each testis to the base of the scrotal sac

gubernaculum is a thickened band of connective tissue - aids in the descent of the gonads (more with testes)

Question 12

The processus vaginalis came from ___________ and covered (was anterior to) the ___________ during development. When does it become the plica vaginalis? What happens if it does not fuse completely to form the plica vaginalis?

Answer 12

• a herniating sac of peritoneum that pushes through the abdominal musculature
• testes
• ninth month of gestation - when the anterior and posterior walls of the processus vaginalis fuse
• indirect/lateral inguinal hernia

Question 13

Which nerves enter the deep ring of the inguinal canal?

Answer 13

testicular nerves (sympathetic), genital branch of the genitofemoral nerve

Question 14

Which nerves exit the superficial ring?

Answer 14

testicular nerves (sympathetic), genital branch of the genitofemoral nerve, ilioinguinal nerve

Question 15

What is Hesselbach’s triangle? What type of hernia is associated with this region?

Answer 15

anterior abdominal wall - defined medially by the lateral margin of the rectus sheath, laterally by inferior epigastric vessels, and inferiorly by the inguinal ligament
Direct Inguinal Hernia

Question 16

What type of hernia is more likely to end up in the scrotum?

Answer 16

indirect inguinal hernia

Question 17

What type of hernia is more common in females?

Answer 17

femoral hernia because their inguinal ligaments are longer and femoral rings are wider

Question 18

What is the difference between inguinal and femoral hernia?

Answer 18

femoral hernia occurs in the femoral canal and is inferior to the inguinal ligament

Question 19

List the differences between direct/medial and indirect/lateral inguinal hernias

Answer 19

direct/medial: passes through Hesslbachs triangle, typically acquired - bladder often included - rarely descend past the superficial inguinal ring - common in elderly

indiret/lateral: herniated material passes through the deep ring - typically congenital - occur on right more often - more common in men because of larger size of inguinal canal

Question 20

The remnant of the processus vaginalis that is reflected upon the testes is called the ___________

Answer 20

tunica vaginalis

Question 21

From which layers of the anterior abdominal wall are the fascial layers forming the spermatic cord derived?

Answer 21

anterolateral abdominal wall

1. internal spermatic fascia: from transversalis fascia
2. middle spermatic fascia - from fascia of the internal abdominal oblique
3. external spermatic fascia - from external oblique aponeurosis

Question 22

What type of hernia is likely to develop as a result of incomplete or lack of closure of the processus vaginalis?

Answer 22

indirect inguinal hernia

Question 23

Define cryptochidism

Answer 23

incomplete testicular descent - testis remains in the abdomen or at some point along the normal developmental pathway

Question 24

Define ectopic testes

Answer 24

abnormal testicular descent - tesis is located outside the normal developmental pathway

Question 25

What are the contents of the inguinal canal in males?

Answer 25

• vas deferens, and artery to vas deferens
• testicular vein, lymphatics, artery, and nerves (sympathetic)
• cremasteric artery
• genital branch of the genitofemoral nerve (cremaster muscle)
• ilioinguinal nerve (does not pass through the deep inguinal ring) - sensory information from superficial regions of external genitalia

Question 26

What are the contents of the inguinal canal in females?

Answer 26

• round ligament (of the uterus)
• ilioinguinal nerve (lateral to the cord like in males)
• genital branch of the genitofemoral nerve
• internal, middle, and external fascias
• strands of the cremaster muscle
• artery of the round ligament

Question 27

Define hydrocele

Answer 27

accumulation of fluid within a patent processus vaginalis - common cause of scrotal enlargement

Question 28

What is the clinical presentation of testicular torsion?

Answer 28

testicular pain and absent cremasteric reflex