S08 and 9 - the Male Reproductive Tract Flashcards
What triggers the production of sperm at puberty?
LH and FSH
What is the general role of the epididymis?
To suspend the sperm in preparation for ejaculation
Summarise the development and descent of the testes.
Develop on the posterior abdominal wall in the abdomen. Descend during embryonic period and continue to develop near the deep inguinal ring.
From 6 weeks before term to a few weeks after birth the testes pass through the inguinal ring.
Swelling in the scrotum are common and can be palpated. What is a hydrocoele and a varicocoele and how might you discriminate between them?
A hydrocoele is when there is a build up of fluid in the scrotum that is not in the veins. It occurs in the tunica vaginalis. This transilluminates and may be from the abdominal cavity draining into the scrotum.
A varicocoele is when there is build up of blood in the testicular veins, this can result from faulty valves. Anatomically at risk due togonal vein coming in perpendicular creating turbulent flow.
Describe the procedure of a vasectomy?
Quick procedure that can be performed at GP surgery. use local anesthetic to make small incisions in scrotum. Cut vas deferens after epididymus and remove small portion. Ends are sealed then scrotum stiched back up.
How do you discriminate between a direct or indirect inguinal hernia?
Direct inguinal hernias will be medial of the inferior epigastric vessels as they herniate directly though the external inguinal ring.
Indirect inguinal hernias will be lateral to the inferior epigastric vessels as they herniate through the deep inguinal ring.
When is an inguinal hernia more likely to happen in a sports person?
If they have weakened abdominal wall due to weakened muscles or tendons. This is more likely in sports where you bend over alot e.g. hockey players
What would be the effect in a male of a damaged pudendal nerve?
The posterior part of the scrotum would lose sensation. Also supplies the sensory fibres of the penis so diminished sensation. Pain after ejaculation.
What is the signal for the process of sperm production to occur in puberty?
Increase in LH and FSH
What are the layers surrounding the testes and what are their origins?
The innermost layer is the internal spermatic fascia-This arises from transversalis fascia.
The middle layer is the cremasteric fascia and arises from the aponeurosis of internal oblique.
The outermost layer is the external spermatic fascia and arises from the aponeurosis of the external oblique.
What are the two key muscles for thermoregulation in the testes and how do they work?
The cremaster muscles is associated with the cremasteric fascia and contracts in responce to cold to pull the testes closer to the body.
The muscle associated with dartos fascia lies outside the external spermatic fascia and is a continuation of scarpas fascia. It will cause the scrotum to wrinkle in response to cold causing decreased surface area.
What is the contents of the spermatic cord?
There are 3 arteries:
-Testicular artery
-Deferential artery (from umbilical)
-Cremasteric artery
3 nerves:
-Genitofemoral (innervate cremaster and dartos)
-Ilioinguinal (L1) (innervation to anterior part of scrotum)
-Autonomic nerves (sym and parasym to testes)
3 Veins:
-Testicular vein
-Pampiniform plexus (thermoregulatory coutercurrent)
-Cremasteric vein
What is the tunica vaginalis and what is it formed from?
It is a bursa that forms from embryological remenants of the processus vaginalis. It has parietal and visceral layers which fuse together.
What is the blood supply and drainage of the scrotum?
The external pudendal artery becomes the anterior scrotal artery which supplies the anterior part of the scrotum.
The internal pudendal artery becomes the posterior scrotal artery and supplies the posterior part of the scrotum.
The venous drainage is by the scrotal veins which join the external pudendal veins.
What is the lymphatic drainage of the testes and scrotum?
The testes drain to the para-aortic lymph nodes.
The scrotum drains to the inguinal lymph nodes.
