How long is the inguinal canal?
4cm
When do the testis usually enter the inguinal canal?
Week 28
When do the testis find themselves in the scrotum?
Week 32
How long does it take to traverse the inguinal canal?
3 days
What is the gubernaculum?
A thick guide wire that connects the testes to the anterolateral abdominal wall at the site of the future deep ring of the inguinal canal
Where does the gubernaculum attach the testes to?
The anterolateral abdominal wall
Where is the embryological origin of the testes?
The extraperitoneal, superior lumbar, posterior abdominal wall
What is the processes vaginalis?
= a diverticulum of the peritonium
Whom are at risk of hydroceles and indirect inguinal hernia?
Men in whom the stalk of the processus vaginalis has not occluded
What does the distal secular part of the processes vaginalis form?
The tunica vaginalis
What is the position of the deep inguinal ring?
Superior to the mid-inguinal ligament, lateral to the inferior epigastric artery
What is the position of the superficial inguinal ring?
Lateral crus = attached to the pic tubercle. Medial crus = attached to the pubic crest
What does the superficial inguinal ring open out of?
The external aponeurosis
What are the fascial coverings of the spermatic cord?
Internal spermatic fascia + cremasteric fascia + external spermatic fascia
From what is the external spermatic fascia formed?
External oblique aponeurosis
From what is the internal spermatic fascia formed?
Transversalis fascia
From what is the cremasteric fascia formed?
Fascia from the superficial and deep surfaces of the internal oblique muscle
What is the contents of the spermatic cord?
1) vas deferens; 2) pampiniform plexus of veins; 3) lymphatics; 4) processus vaginalis; 5) genital branch of the genitofemoral nerve; 6) sympathetic nerve fibres; 7) testicular artery; 8) artery of the ductus deferens; 9) cremasteric artery
What are the layer of the scrotum?
Skin — Scarpa fascia — dartos fascia (containing dartos muscle fibres) — Colles fascia — deep fascia (1. external spermatic fascia; 2. cremasteric fascia; 3. internal spermatic fascia)
From what does the perineal artery branch from?
The internal pudendal artery, from the internal iliac artery
From what does the deep external pudendal artery branch from?
The femoral artery, from the external iliac artery
What is the blood supply to the scrotum?
1) Posterior scrotal branches of the perineal artery; 2) anterior scrotal branches of the deep external pudendal artery; 3) cremasteric artery
Which testis is suspended lower than the other?
L
What is the purpose of the fluid in the tunica vaginalis?
Free movement of the testes within the scrotum
What is the capsule of dense connective tissue that surrounds the testes?
Tunica albuginea
What shape of the testicular lobules?
Pyramidal
How is testis temperature regulated?
Dartos muscle + cremaster muscle + counter-current mechanism of the pampiniform plexus of veins
How many seminiferous tubules are contained within a testicular lobule?
1-4
What are the layers of the tunica vaginalis?
Outer parietal layer (lining the scrotum) + inner visceral layer (covering the tunica albuginea)
How long is the epididymis?
4-5m
How long are the seminal vesicles?
15cm
What % of semen do seminal vesicles contribute?
60%
What do seminal vesicles contribute to semen?
Flavins
Fructose
Ascoribic acid
What % of semen does the prostate contribute?
20%
What does the prostate contribute to semen?
Zinc
What are the accessory glands of the male reproductive system?
1) Seminal vesicles; 2) prostate gland; 3) bulbourethral glands
What is the alternative name for the bulbourethral glands?
Cowper glands
What % of semen do the bulbourethral glands contribute?
<5%
What do the bulbourethral glands contribute to semen?
Alkaline mucus
What % of semen does the testes contribute?
15%
What does the testes contribute to semen?
Sperm
What % of semen do the epididymis’ contribute ?
<5%
What are the zones of the prostate?
Transition zone = 5% (in which the prostatic urethra runs); central zone = 25%; peripheral zone = 70%
The arteries supplying the penis (not penile skin), form what artery do they branch?
Internal pudendal artery
What size are the bulbourethral glands, and where are they located?
3-5mm, located at the urogenital diaphragm
What is the name given to when the vas deferens opens into the prostatic urethra?
Ejaculatory duct
What, aside from he accessory glands, contribute to semen?
Testes and epididymis
What are the different parts of the urethra?
1) Pre-prostatic; 2) prostatic; 3) membranous; 4) spongy
What are the erectile tissues of the penis?
2x corpora cavernosa; 1 x corpus spongiosum
What are the crura, and to what are they attached?
= the point posteriorly where the corpora cavernous separate, each crura attaching to the corresponding ischial rams
What structures comprise the root of the penis?
Crura - the corpora cavernous
Bulb - corpus spongiosum
Ischiocavernosus muscles
Bulbospongiosus muscles
What is the arterial supply to the penis (not penile skin)?
1) Dorsal arteries of the penis - run between the corpora cavernosa; 2) deep arteries of the penis - run through the corpora cavernosa; 3) arteries of the bulb of the penis
What arteries supply the penile skin?
Superficial and deep branches of the external pudendal arteries
What nerves mediate penile erection?
Pelvic splanchnic nerves (parasympathetic S2-S4) - brings about increased blood flow into, but decreased venous drainage out of, the cavernous spaces of the penis
What nerves mediate ejaculation?
Sympathetic nervous system (T10-L2) = closure of the bladder neck and contraction of the seminal vesicles (resulting in deposition of semen in the posterior urethra)
Somatic and visceral nerves (S2-S4) stimulate muscular contraction
What muscles are involved in ejaculation?
1) Superficial transverse perineal muscles; 2) bulbospongiosus muscles; 3) ischiocavernous muscles