Description

• Twisting of testis and spermatic cord, resulting in acute ischemia and loss of testis if unrecognized:
  • Intravaginal torsion: occurs within tunica vaginalis, only involves testis and spermatic cord. Most commonly seen in practice.
  • Extravaginal torsion: involves twisting of testis, cord, and processus vaginalis as a unit; typically seen in neonates
• System(s) affected: reproductive

Geriatric Considerations
Rare in this age group

Pediatric Considerations
Peak incidence at age 14 years

Epidemiology

Incidence

• ~1/4,000 males before age 25 years
• Predominant age:
  • Occurs from newborn period to 7th decade
  • 65% of cases occur in 2nd decade, with peak at age 14 years; rare beyond the age of 30 years
  • Second peak in neonates (in utero torsion usually occurs around week 32 of gestation)

Etiology and Pathophysiology

• Initial incomplete twisting of spermatic cord causes venous obstruction and edema of testis, leading to congestion and then to ischemia.
• Complete twisting of the spermatic cord causes arterial occlusion, in addition to the above, leading to rapid ischemia.
• Congenital bell clapper deformity, which is bilateral in at least 2/5th of cases: A high mesorchium (the posterolateral attachment of the testis to the tunica vaginalis) allows more room for the testis to twist within the tunica vaginalis and is associated intravaginal testicular torsion.
• No clear anatomic defect is associated with extravaginal testicular torsion:
  • In neonates, the tunica vaginalis is not yet well attached to scrotal wall, allowing torsion of entire testis including tunica vaginalis.
• Usually spontaneous and idiopathic
• 20% of patients have a history of trauma.
• 1/3 have had prior episodic testicular pain.
• Contraction of cremaster muscle or dartos may play a role and is stimulated by trauma, exercise, cold, and sexual stimulation.
• Increased incidence may be due to increasing weight and size of testis during pubertal development.
• Possible alterations in testosterone levels during nocturnal sex response cycle; possible elevated testosterone levels in neonates
• Testis must have inadequate, incomplete, or absent fixation within scrotum.
• Torsion may occur in either clockwise or counterclockwise direction.

Genetics

• Unknown
• Familial testicular torsion, although previously rarely reported, may involve as many as 10% of patients.

Risk Factors

• May be more common in colder months
• Paraplegia
• Previous contralateral testicular torsion