O&G surgical incisions and male infertility

Question 1

Describe the normal findings on clinical examination, including the normal size of an adult testis, the location of the epididymis, vas deferens.

Answer 1

Normal size of adult testis = 12-25 ml and should measure ~5 cm in length
The epididymis lies along the posterolateral border of each testis and, if normal, is difficult to palpate
The vas deferens can be palpated in the spermatic cord as a firm tubular structure

Question 2

In which conditions might the testis be small or difficult to palpate?

Answer 2

Any condition that causes testicular failure (e.g. Kleinfelter’s syndrome, post-chemotherapy or post-orchitis) will cause reduced testicular volume making the testes difficult to palpate
The testes may be very small or not present in the scrotum (an undescended testis) making them difficult to palpate

Question 3

Describe the anatomical relationships of the prostate gland

Answer 3

The prostate gland lies at the base of the bladder, clasping the urethra

Question 4

How can the prostate gland be examined?

Answer 4

Prostatic enlargement can be palpated by rectal examination

Question 5

Name the erectile tissue and perineal muscles that assist in penile erection

Answer 5

Erectile tissue - ventral corpus spongiosum and the dorsal corpora cavernosa (x2)
Perineal muscles - bulbospongiosus muscle and ischiocavernosus muscle

Question 6

Name the accessory glands and explain their functions

Answer 6

Epididymis & vas deferens - exit route from testes to urethra, concentrate & store sperm, site for sperm maturation
Seminal vesicles - produce semen into ejaculatory duct, supply fructose, secrete prostaglandins, secrete fibrinogen
Prostate gland - produces alkaline fluid, produces clotting enzymes to clot semen within female
Bulbourethral glands - secrete mucus to act as lubricant

Question 7

Explain the significance of the arterial supply of the spermatic cord in relation to torsion

Answer 7

The testis is suspended in the scrotum on a vascular pedicle, it could twist around and obstruct its blood supply. This is testicular torsion and is a surgical emergency

Question 8

Explain the significance of venous drainage of the spermatic cord in relation to varicocele. (Bonus - which side is more commonly affected?)

Answer 8

A varicocele is a common condition in which the veins around the testis become distended and elongated. This is more common on the left, as the vein joins the higher pressure left renal vein (right joins the IVC)

Question 9

Explain the significance of the lymphatic drainage of the spermatic cord in relation to tumour spread

Answer 9

Malignant tumours of the testes spread lymphatically to para-aortic nodes to the level of L1. It is only when the tumour spreads locally to the scrotum that the superficial inguinal lymph nodes are involved

Question 10

Describe common O&G incision sites on the anterior abdominal wall

Answer 10

Midline vertical incision - goes through the linea alba, which is relatively avascular, therefore rapid & bloodless access to the abdominal cavity is achieved but this means healing is more difficult due to poor blood supply
Suprapubic incision - better cosmetic results, less pain, lower incidence of hernia formation but access is slower, blood loss is greater and nerve injury is more frequent

Question 11

Describe the changes in surface anatomy that occur to the uterus during pregnancy

Answer 11

The uterine fundus can start to be palpated above the pubic symphysis from 12 weeks gestation and by 20 weeks it reaches the umbilicus and from there it grows at about 1 cm per week until reaching near the xiphisternum at around 36 weeks.
From 36 weeks onwards the fundal height may decrease as the head starts to descend into the maternal pelvis

Question 12

Describe the course of the inferior epigastric artery`

Answer 12

The inferior epigastric artery is a branch of the external iliac artery. It runs up from above the inguinal ligament, piercing the transversalis fascia to ascend behind the rectus sheath and anastomoses with the superior epigastric artery. Together they supply the central part of the abdominal wall.

Question 13

How is the inferior epigastric artery avoided during insertion of a lateral port during laparoscopy?

Answer 13

One must know its expected surface markings; immediately medial to the deep inguinal ring at the midpoint of the inguinal ligament (ASIS to pubic tubercle), or it is superior to the femoral pulse felt at the mid-inguinal point (ASIS to pubic symphysis)
The artery passes obliquely up the abdomen towards a point about 2-3 cm lateral to the umbilicus

Question 14

What structures are incised during an elective caesarean section?

Answer 14

Skin -> superficial fascia -> rectus sheath (note there is no posterior layer to the rectus sheath as the incision is inferior to the arcuate line) -> rectus muscles are separated but not incised -> parietal peritoneum -> visceral peritoneum -> uterus -> amniotic sac

Question 15

What procedures are performed to minimise the risk of damage to the bladder?

Answer 15

Patient is catheterised before the procedure to reduce the size of the bladder. Bladder is gently pushed down anterior to the uterus towards the vagina, away from the surgical field

Question 16

Why is it important to suture the rectus sheath on closing the anterior abdominal wall?

Answer 16

To reduce the risk of wound hernia formation