Pelvis - Male And Female

Question 1

Differences between the male and female pelvic inlets?

Answer 1

Male - heart shaped

Female - circular (also larger)

Question 2

An osteologist measure the pubic arch of a pelvis to be 63 degrees. Is this a female or male pelvis?

Answer 2

Male pelvis, pubic arch is narrow (less than 70 degrees)

Question 3

You are looking at a pelvis that has the following features;
It is thin and light
It has an oval obturator foramen
It has a broader pubic arch (above 90 degrees)
Pelvic outlet is large

Would this be bones from. Male or female? What is the reason behind these differences?

Answer 3

These features describe female pelvis osteology.

The reason for these features suit requirements for childbirth.

Question 4

What is the pelvic diaphargm and what muscles make up e pelvic diaphragm?

Answer 4

The muscles levator ani and coocygeus make it up.
These muscles form a muscular sling
Pelvic diaphragm is a part of the pelvic floor

Question 5

What structures make up the pelvic floor?

Answer 5

• pelvic diaphragm
• perineal membrane
• deep perineal pouch

Question 6

What muscles make up the pelvic wall?

Answer 6

Piriformis (originates at anterior sacrum and goes through greater sciatic foramen) 
Obturator Internis (covers obturator membrane at obturator foramen)

Question 7

What are the contents of the anal triangle?

Answer 7

Anal aperture
External anal sphincter muscle
2 ischioanal fossae

Question 8

What is the perineal body and what is its clinical relevance?

Answer 8

Is a lump of fibrous tissue in the centre of the anal and urogenital triangles.

• supports pelvic floor
• clinical relevance; during childbirth it can be stretched and damaged. Infection, trauma and inflammatory diseases can also cause damage

Question 9

What is the isciorectal fossa and what is its clinical relevance?

Answer 9

Found at the anal triangle, it is a wedge shaped fossa that contains mostly fat.

• crossed by inferior rectal nerve and artery
• lateral wall: pudendal canal containing pudendal vessels (pudendal nerve block)

Question 10

Describe the coarse of the pudendal nerve

Answer 10

Pudendal nerve arises from sacral plexus (S2,3,4), it leaves via the greater sciatic foramen along with internal pudendal artery

Pudendal nerve then passes below piriformis back through lesser sciatic foramen

Question 11

What is the clinical relevance of the pudendal nerve?

Answer 11

Pudendal nerve blocked during vaginal delivery Travels over ischial spine, which can be palpated and anaesthetic agent is injcted here

Question 12

What are the branches if pudendal nerve?

Answer 12

Perineal, dorsal nerve of clitoris (females), inferior rectal

Question 13

What is the sensory and motor function of pudendal nerve?

Answer 13

Motor;
- skeletal muscles of perineum, external anal sphincter, externa, urethral sphincter, levator ani

Sensory;
- penis, clitoris, skin of perineum

Question 14

Where is the cremasteric muscle and what occurs during the cremasteric reflex?

Answer 14

Unilateral elevation of the testis on stroking the inner thigh

Muscle derived from internal oblique and transversus abdminus