TWIST Score

Risk stratification for testicular torsion — determine need for immediate surgery vs scrotal ultrasound

Indication

Risk stratification for testicular torsion — determine need for immediate surgery vs scrotal ultrasound

id: testis_swelling; label: Testis swelling; type: options; options: value: 0; label: Absent; value: 2; label: Present
id: hard_testis; label: Hard testis on palpation; type: options; options: value: 0; label: Absent; value: 2; label: Present
id: absent_cremasteric; label: Absent cremasteric reflex; type: options; options: value: 0; label: Present (normal); value: 1; label: Absent
id: nausea_vomiting; label: Nausea or vomiting; type: options; options: value: 0; label: Absent; value: 1; label: Present
id: high_riding; label: High-riding testis; type: options; options: value: 0; label: Absent; value: 1; label: Present

function(score) { if (score <= 1) return { risk: 'Low Risk', tier: 'low', action: 'Low probability of torsion. Scrotal ultrasound recommended to evaluate. Close follow-up if ultrasound unavailable.', color: 'green', }; if (score <= 4) return { risk: 'Intermediate Risk', tier: 'medium', action: 'Intermediate probability. Urgent scrotal Doppler ultrasound required. Do not delay — torsion is time-sensitive.', color: 'yellow', }; return { risk: 'High Risk — Surgical Emergency', tier: 'high', action: 'High probability of testicular torsion. Immediate urology consult and surgical exploration without waiting for ultrasound. Time to detorsion is critical — salvage rates: >90% if <6hrs, ~50% at 12hrs, <10% at 24hrs.', color: 'red', }; }

TWIST ≥5: go directly to OR — do not wait for ultrasound. Every minute counts.
Salvage rate is >90% if detorsion occurs within 6 hours of symptom onset
A normal ultrasound does not rule out torsion — if clinical suspicion is high, explore surgically
Intermittent torsion can present with normal ultrasound between episodes — treat clinically
Bell-clapper deformity is bilateral — contralateral orchiopexy should be performed at same operation