TWIST score

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The Testicular Workup for Ischemia and Suspected Torsion (TWIST) score is a clinical decision tool used for the workup and management of acute scrotal emergencies where torsion is suspected. It uses history and examination to estimate the likelihood of torsion. Currently, validation of the clinical score has only been conducted in pediatric population. It aims to reduce the number of unnecessary ultrasounds in cases of suspected torsion.

Criteria

  • testicular swelling (two points)
  • hard testes (two points)
  • absent cremasteric reflex (one point)
  • nausea or vomiting (one point)
  • high riding testicle (one point)

Interpretation

  • score 0-2: low risk
    • 100% negative predictive value for torsion
    • generally no ultrasound or urological consultation required
  • score 3-4: intermediate risk
    • ultrasound warranted
  • score 5 or above: high risk
    • 100% positive predictive value for torsion
    • ultrasound not required, urgent urological consultation and surgery required to salvage testicle