Practical topic 32 Flashcards
Penis and its musculature, scrotum, testis, funiculus spermaticus, their nerves and blood supply
- What are the main structures of the penis?
- What covers these structures?
- Penis consists of:
- Root
- Body
- Glans
- The prepuce covering (some of) these structures
Prepuce
Parts
- Smooth internal layer
- Hairy external layer
- Fonix
- Deepest recess
- M. protractor preputii
Prepuce
Blood supply
Branches of:
- A. penis dorsalis (anastomosing branches)
- A. pudenda externa (running in canalis inguinalis)
- A. bulbi penis
Prepuce
Innervation
- N. penis dorsalis
- Rr. preputalis (ex. n. pudenda)
- N. genitofemoralis
- N. cutaneous lateralis
Radix penis
Corpus penis
Glans penis
Give the muscles of the penis
- M. retractor penis
- M. ischocavernosus
- M. bulbospongiosus
- M. ishiourethralis
Mention:
- M. urethralis
- M. preputalis cranialis
- M. preputalis caudalis
M. retractor penis
Origin: Ventral surface of sacrum (or first 2 caudal vertebrae)
Insertion: Blends with external anal sphincter, extends distally on ventral surface of penis at the level of the glans
Action: Retracts penis onto the prepuce
Innervation:
M. ischocavernosus
Origin:
- Arcus ishiadica
- Tuber ishiadicum
Insertion: Extends to the proximal end of corpus penis
Action:
- Encloses crura
- Raises erect penis (compresses the crura, erecting corpus cavernosus distally)
Innervation:
M. bulbospongiosus
Origin: Extrapelvic continuation of the striated m. urethralis
Insertion: Extends to the proximal end of the shaft of the penis
Action: Pulsatile contraction during ejaculation
Innervation:
M. ishourethralis
Originates from the dorsal part of tuber ishiadicum, and forms a fibrous ring around the common trunk of the left and right dorsal vein.
Give the layers of the scrotum
- Cutis scroti
- Tunica dartosa
- Fascia spermatica externa
- M. cremaster (fascia)
- Origin: in m. obliquus abdominalis interna
- Fascia spermatica interna
- Can’t really see
- Tunica vaginalis
Give the parts of the testis
- Extremitas capitata
- Extrimitas caudate
- Margo epididymalis
- Margo libre
Testis
Give the parts of the epididymis
- Caput epididymis (head)
- Corpus epididymis (body)
- Cauda epididymis (tail)
- Continuous with the ductus deferens
- Bursa testicularis
- Found between body of epididymis and testis
Funiculus spermaticus
What does it consist of?
- AV. testicularis
- Lymphatics
- Testicular plexus of nerves
- Smooth muscle
- Ductus deferens
Give the blood supply in this topic
- A. penis
- A. testicularis
- V. testicularis
A. penis
- Ex. a. pudenda interna, ex. a. iliaca interna
- Gives off:
- A. bulbi penis
- To corpus spongiosum penis
- A. profunda
- Through tunica albuginea and raifies in the corpus cavernosum
- A. dorsalis penis
- To the tip of the penis
- A. bulbi penis
A. testicularis
- Ex. aorta abdomialis (paired branches)
- As a part of the spermatic cord, it reaches the testis
- Gives off:
- Rr. epididymales
V. testicularis
- Right:
- Ex. vena cava caudalis
- Left:
- Enters renal vein, which then drains into vena cava caudalis
Scrotum
Blood supply
A. pudenda externa → r. scrotalis + a. cremasterica to m. cremaster
Testis
Blood supply
- A. abdominalis → a. testicularis
- V. testicularis → plexus pampiniformis
Epididymis
Blood supply
A. testicularis
Innervation
- Paired pelvic (parasympathetic) and pudendal (mixed) nerves, from the lumbar and sacral plexus
-
Hypogastric nerves (sympathetic) from pelvic plexus
- For ejaculation and prostatic secretion
