Blood supply & Lymphatics & Innervation - Male reproductive system

Testes & epididymis venous drainage

• testicular venous plexus → testicular vein

• Lt drains to renal vein, Rt drains to IVC

What nerves supply the testes?

• renal & aortic plexus → testicular plexus, for pain sensation & control blood vessel tone

Where does lymph from testes drain to?

• para-aortic lymph nodes

• NOT inguinal as testes develop in the abdomen & descend from there

What nerves supply the scrotum skin?

• anterior: L1/2 → ilioinguinal n, genitofemoral n (genital)

• posterior: S2-S4 → pudenal n, post femoral cutaneous n

What nerve supply the muscles in the scrotal sac - Dartos & cremaster?

• Dartos (smooth muscle) → sympathetic fibres from ilioinguinal n, post scrotal n

  • wrikles scrotum

• cremaster (skeletal muscle) → genitofemoral n (genital)

  • elevate testes

Testes are supplied by the renal and aortic plexus, but the scrotum is supplied by nerves from much lower down (ilioinguinal, genitofemoral, pudendal, femoral cutaneous).

These structures also have distinctively different blood supply.

Why?

• testes originate from the abdomen, near the kidneys

  • carry their own blood and nerve supply from the abdomen when they descend

• scrotum develops from labioscrotal swellings in the body wall

scrotum lymphatic drainage

superficial inguinal

vas deferens arterial supply & veinous drainage

• supply: internal iliac a → superior vescial a → a of ductus deferens

• drainage: v of ductus deferens → vesical venous plexus → internal iliac v

prostate blood supply and venous drainage

• supply: internal iliac → inf vesical a, some supply from middle rectal a

• drainage: prostatic venous plexus → internal iliac v

  • communicates with vesical & vertebral venous plexus

The prostate venous plexus communicates freely with the vesical and vertebral venous plexus (Batson’s plexus). What is the clinical significance?

• Batson venous plexus is a network of valveless veins, connecting the pelvic and thoracic veins to internal vertebral veins

• possible pathway for prostate cancer metastasis to vertebral column & brain

prostate lymph drainage

• mainly internal iliac nodes & sacral nodes

• some drainage to external iliac

• then lumbar trunk → cisternal chyli → thoracic duct

What nerve supply the prostate? What are their functions?

• inferior hypogastric plexus → prostate plexus

  • sympathetic fibres from hypogastric nerves: ejaculation

  • parasympathetic fibres from pelvic splanchnic nerves (S2-S4)

Penis: arterial supply & venous drainage

• supply:

  • internal iliac a → internal pudenal a → dorsal a (skin & glans), deep a (in cavernosa), bulbourethral a

• drainage:

  • skin & subcut: superficial dorsal v → superficial external pudendal v → great saphenous v

  • deep erectile tissue: deep dorsal v → preprostatic venous plexus

Lymphatic drainage of the penis

• skin → superficial inguinal

• glans & deep structures → deep inguinal → ext iliac

Nerve supply of the penis

• somatic: S2-S4 pudendal n → dorsal n of penis (sensory) & perineal n (motor)

• autonomic: form cavernous n & run with dorsal n to supply erectile tissue

  • parasympathetic (erection): S2-S4 pelvic splanchnic n

  • sympathetic (ejaculation): hypogastric nerves