Mnemonic

Rule of Three in the Spermatic Cord

A mnemonic for the contents of the spermatic cord.

Expansion

Three arteries, three nerves, three other structures

Mnemonic

The rule of three: three arteries, three nerves, three other structures.

Three arteries:

  • Testicular artery
  • Artery to the vas (deferential)
  • Cremasteric artery

Three nerves:

  • Genital branch of the genitofemoral nerve
  • Ilioinguinal nerve, which runs on top of the cord rather than in it
  • Autonomic fibres

Three others:

  • Vas deferens
  • Pampiniform plexus
  • Lymphatics

Three coverings, acquired as the testis descends: external spermatic fascia from external oblique, cremasteric fascia from internal oblique, internal spermatic fascia from transversalis fascia.

Expansion

Three arteries

  • Testicular artery
  • Artery to the vas deferens (from the inferior vesical)
  • Cremasteric artery (from the inferior epigastric)

Three nerves

  • Genital branch of the genitofemoral nerve
  • Sympathetic fibres
  • Ilioinguinal nerve - strictly on the cord rather than in it

Three other structures

  • Vas deferens
  • Pampiniform venous plexus
  • Lymphatics

The pampiniform plexus wraps around the testicular artery as a countercurrent heat exchanger, cooling arterial blood and keeping the testis a few degrees below core temperature.