Anatomy Station Questions

Question 1

what is meant by the perineum?

Answer 1

a shallow compertment / space that lies between the levator ani superiorly and the perineal skin inferiorly

Question 2

what are the contents of the perineum?

Answer 2

• the distal ends of the pelvic organs passing to the exterior
• the exterior genitalia
  the blood and nerve supply
• venous and lymphatic drainage to all the contents

Question 3

what are the important anatomical relationships of the pudendal nerve?

Answer 3

crosses the lateral aspect of the sacrospinous ligament, nears its attachment to the ischial spine

Question 4

why might a perineal abscess spread readily thorough the ischioanal / ischiorectal fossa?

Answer 4

it is a large space filled with fat and losse connective tissue
fat has a poor blood supply with few immune cells and so presents minimal barrier to spread of infection

Question 5

what are the nerve roots to the pudendal nerve?

Answer 5

S2,3,4

Question 6

what type of nerve fibres does the pudendal nerve contain?

Answer 6

somatic motor (to the levator ani and the muscles of the perinuem) and somatic sensory from the perinuem (there will also be sympathetic fibres as there are in all spinal nerves)

Question 7

if a pudendal nerve block is performed during labour, are the uterine contractions affected?

Answer 7

a pudendal nerve block provides local anaesthesia over dermatomes S2-S4, which is the majority of the perineum, and the inferior quarter of the vagina
- it does not block pain from the uteris, cervix or superior vagina so ther mother is able to feel uterine contractions
the pudendal nerve has no control over motor innervation of the uterus so the contractions themselves are not affected either

Question 8

describe the motor and sensory innervation provided by the pudendal nerve?

Answer 8

main motor innervation to the perineum as well as providing senosry innervation to most of the skin of the perineum and external genitalia
it provides innervation to eh perineal muscles, the enternal anal sphincted and the external urethral sphincter

Question 9

where do you inject lidocaine for pudendal nerve block?

Answer 9

1cm inferior and medial in relation to the sacralspinous ligament to the ischial spine

Question 10

which lymph nodes to the ovaries drain into?

Answer 10

lumber (caval / aortic) lymph nodes

Question 11

how would you drain fluid from the rectouterine (pouch of douglas) ?

Answer 11

via a needle placed through the posterior formix of the vagina

Question 12

which structure is formed by a double layer of peritoneum, extending between the uterus and the lateral pelvis walls and floors?

Answer 12

broad ligament

Question 13

how far do catheters need to be inserted in males and females for urinary catheterisation?

Answer 13

females - 4-5cm

males - 18-22cm

Question 14

what are the components of fluid secreted by the seminal vesicle?

Answer 14

proteins, enzymes, fructose, mucus, vitamin C, flavins, phosphorylcholine and prostaglandin

Question 15

what is the main function of the fluid secreted by prostate gland?

Answer 15

activating sperm

Question 16

what are the functions of the fluid / mucus secreted by the bulbourethral (Cowper’s) glands?

Answer 16

lubricates urethra and helps to neutralise acid in the urethra

Question 17

what is the anatomical position of the pelvis?

Answer 17

the ASIS and the pubic tubercle should be in the same plane as each other

Question 18

what is the vertex in a foetal skull?

Answer 18

an area outlined by the anterior and posterior frontanelles and the parietal eminances

Question 19

what are the diameters of the vertex?

Answer 19

the occipitofrontal diamete is longer than the biparietal diameter (ie the foetal head is longer than it is wide)

Question 20

at which vertebral level does the spinal cord end in an adult?

Answer 20

L2

Question 21

at which level is an epidural or spinal anaesthetic needle usually inserted?

Answer 21

L3/L4 IV disc level

Question 22

why are breast cancers found in the arm pits?

Answer 22

drains to the axillary nodes

Question 23

what is the blood supply to the uterus?

Answer 23

the uterine arteries, which are branches of the internal iliac

Question 24

what anastamoses occur in the uterus?

Answer 24

uterine arteries anastomose freely with each other and with the ovarian arteries, which tend to supply the fundus
consequently venous drainage of the uterus is mainly to the internal iliac veins, but also to the ovarian veins
uterine arteries also anastomose with vaginal arteries around the superiro vaginal region

Question 25

what are the origins of arteries contributing to the anastomosis?

Answer 25

uterine artereis from the internal iliac and ovarian from the abdominal aorta
vaginal artery is usually a branch of uterine artery