How to rule out testicular torsion?

How to Rule Out Testicular Torsion

Testicular torsion is a surgical emergency that requires immediate evaluation and intervention within 4-8 hours of symptom onset to prevent testicular loss. Doppler ultrasound showing decreased or absent blood flow is the definitive diagnostic test to rule out testicular torsion when clinical suspicion exists. 1, 2

Clinical Evaluation

Key Clinical Features to Assess:

• Onset of pain: Sudden onset strongly suggests torsion (vs. gradual onset in epididymitis) 1, 2
• Prehn's sign: Pain relief with testicular elevation suggests epididymitis, not torsion 1
• Cremasteric reflex: Absent reflex suggests torsion (present in epididymitis) 1, 3
• Testicular position: High-riding testicle suggests torsion 1, 2
• Associated symptoms: Nausea and vomiting commonly accompany torsion 4, 2

TWIST Score Assessment:

The TWIST (Testicular Workup for Ischemia and Suspected Torsion) Score can help stratify risk 1:

• Testicular swelling (2 points)
• Hard testicle (2 points)
• Absent cremasteric reflex (1 point)
• Nausea/vomiting (1 point)
• High-riding testis (1 point)

Score interpretation:

• ≥5 points: High risk (92.9% positive predictive value)
• Consider immediate surgical exploration without imaging delay

Diagnostic Testing

Imaging Studies:

• Doppler ultrasound: First-line imaging test 1, 5

  • Look for: Decreased or absent blood flow to affected testicle
  • Caution: Incomplete torsion may still show some blood flow 5
  • Note: Should not delay surgical intervention if clinical suspicion is high 2

• Radionuclide testicular scintigraphy:

  • Alternative when beyond acute phase (>12 hours) 4
  • Less commonly used due to time constraints and availability

Management Algorithm

1. High clinical suspicion (TWIST score ≥5 or classic presentation):

   • Proceed directly to surgical exploration without imaging delay 2, 3
   • Do not wait for imaging if clinical presentation strongly suggests torsion

2. Moderate clinical suspicion:

   • Immediate Doppler ultrasound if available without significant delay 5, 6
   • Consider manual detorsion attempt while preparing for surgery 3
     • External rotation of the testicle (usually outward)
     • Must confirm restoration of blood flow after maneuver
   • Proceed to surgical exploration if ultrasound confirms torsion or is unavailable

3. Low clinical suspicion with alternative diagnosis likely:

   • Doppler ultrasound to confirm alternative diagnosis 1
   • Consider other diagnoses in differential (epididymitis, torsion of testicular appendage)

Common Pitfalls to Avoid

• Delaying surgical intervention: Critical 4-8 hour window for testicular salvage 2, 3
• Over-reliance on imaging: Clinical diagnosis should prompt immediate action; don't wait for imaging if high suspicion 2
• Misinterpreting incomplete torsion: May still show some blood flow on Doppler 5
• Misdiagnosing as epididymitis: Especially in prepubertal males where epididymitis is rare 3
• Missing the "blue dot sign": Indicates torsion of testicular appendage (not testicular torsion) 3

Differential Diagnosis Comparison

Feature	Testicular Torsion	Epididymitis
Onset	Sudden	Gradual
Pain relief with elevation	No	Yes (Prehn sign)
Cremasteric reflex	Absent	Present
Testicular position	High-riding	Normal
Doppler ultrasound	Decreased/absent flow	Increased flow

Remember that testicular torsion is a time-sensitive emergency, and when in doubt, surgical exploration is warranted to prevent testicular loss and preserve fertility 2, 3.