Key Facts

Testicular torsion is a surgical emergency requiring prompt recognition and intervention. Delay in diagnosis and treatment leads to irreversible ischaemic damage and testicular loss. It accounts for approximately 25% of acute scrotal presentations in children.

Epidemiology

Annual incidence is approximately 1 in 4,000 males under 25 years. Peak incidence at 12-18 years (second peak in neonates). Left-sided torsion is slightly more common. The condition accounts for approximately 25-35% of all acute scrotal presentations in boys.

Aetiology

• Bell clapper deformity: Tunica vaginalis completely surrounds the testis, allowing free rotation (present in ~12% of males bilaterally)
• Extravaginal torsion: Neonatal — entire spermatic cord twists above the tunica vaginalis
• Intravaginal torsion: Post-pubertal — testis twists within the tunica vaginalis
• Precipitants: Physical activity, trauma, cold weather, sleep (cremasteric reflex activity)

Pathophysiology

Torsion of the spermatic cord occludes the testicular veins initially (venous congestion), followed by arterial compromise as oedema increases. The resulting ischaemia leads to infarction if not corrected within 6-8 hours. The degree of torsion matters — 360° or greater has worse outcomes than 180°.

Typical Presentation

• Sudden-onset severe unilateral scrotal pain
• Often wakes the patient from sleep
• Nausea and vomiting (common)
• Pain may radiate to the lower abdomen/inguinal region

Clinical Signs

• Swollen, tender, erythematous hemiscrotum
• High-riding testis with horizontal lie
• Absent cremasteric reflex (most sensitive sign)
• Thickened spermatic cord
• Prehn's sign negative (elevating testis does NOT relieve pain — unreliable)

Torsion of Testicular Appendage

• More gradual onset, localised tenderness at upper pole
• Blue dot sign: Visible through scrotal skin at upper pole
• Cremasteric reflex usually preserved

Red Flags

• Acute scrotal pain in a boy aged 12-18 years — torsion until proven otherwise
• Bilateral testicular pain — bilateral torsion (rare but reported)
• Neonatal hard, non-tender testis with blue discolouration — antenatal torsion (usually unsalvageable)

Bedside

• Clinical assessment: This is primarily a clinical diagnosis — do not delay for imaging
• Cremasteric reflex: Stroke inner thigh — absent reflex strongly suggests torsion

Bloods

• FBC, CRP: If infection suspected (usually normal in torsion)
• Urine dipstick: Usually normal in torsion; positive in epididymo-orchitis

Imaging

• Doppler USS: Shows absent/reduced blood flow — sensitivity 88-95%, specificity 90-99%
• Important: USS should NOT delay surgical exploration if clinical suspicion is high
• USS is most useful when diagnosis is uncertain (e.g., gradual onset, atypical features)

Special Tests

• Surgical exploration: The definitive diagnostic AND therapeutic intervention
• No other special tests are routinely required

Non-pharmacological

• Manual detorsion (open book technique — lateral rotation): Can be attempted as a temporising measure while awaiting surgery; does not replace surgical exploration
• Nil by mouth: Prepare for emergency surgery

Pharmacological

• Analgesia: Morphine 0.1-0.2mg/kg IV for pain control
• Antiemetic: Ondansetron 0.1mg/kg IV if vomiting
• Prophylactic antibiotics: Not routinely required unless orchidectomy performed

Surgical/Interventional

• Emergency scrotal exploration: Within 6 hours of symptom onset
• Detorsion and assessment of viability: Wrap testis in warm saline-soaked gauze and reassess after 10-15 minutes
• Bilateral orchidopexy: Fix both testes with 3-point non-absorbable sutures (contralateral testis is at risk due to bilateral bell clapper deformity)
• Orchidectomy: If testis non-viable after detorsion — consider prosthesis at later date

Referral Criteria

• All suspected testicular torsion — immediate surgical referral (within minutes, not hours)
• Do not delay for imaging or specialist opinion if clinical suspicion is high
• Post-orchidectomy — offer testicular prosthesis discussion

• Testicular salvage rate: >90% if explored within 6 hours; 50% at 12 hours; <10% at >24 hours
• Fertility: Contralateral testis usually compensates; fertility rates are near-normal after unilateral orchidectomy
• Recurrence: <5% after bilateral orchidopexy
• Testicular atrophy: May occur even after successful detorsion (up to 50% have some degree of atrophy)
• Medicolegal: Missed testicular torsion is one of the most common urological litigation claims

Salvage Rate by Duration

Differentiating Torsion from Epididymo-orchitis