emDOCs Podcast – Episode 83: Testicular Torsion

Background

• Testicular torsion has essentially no associated mortality, little morbidity, and no literature support for diminished fertility.  However, patients remain concerned about losing a testicle, and there is high medicolegal risk.
• Several mimics of testicular torsion:
  • Epididymitis, orchitis, and UTIs
  • Torsion of the appendix testis or appendix epididymis → Blue dot sign
  • Sexually transmitted infections
  • Oncologic diagnoses 
    • Diffusely hard testicle → lymphoma and leukemia
  • Idiopathic edema, hernia, hydroceles, varicocele 
    • Fluctuating pain/swelling, positional swelling
  • Trauma  → Ecchymoses, visible injury
• Pathophysiology
  • Twisting of the testicle along the spermatic cord → ↓venous outflow → vascular congestion →swollen/painful testicle
  • ↑ pressure and/or further twisting → ↓ arterial flow → ischemia  
    • Severity depends on duration & degree of cord rotation.
    • Severe ischemia and necrosis start in 4-6 hours
•  Two forms: 
  • Intravaginal
    • Adolescents/young adults
    • Abnormal attachment of the tunica vaginalis
    • Bell clapper deformity allows spermatic cord to twist
  • Extravaginal
    • Neonates
    • Tunica vaginalis is not adhered to the gubernaculum
    • Tunica vaginalis and spermatic cord twist together.

What are risk factors?

• Bimodal age of distribution: at birth and 12-18 years 
  • 14% of cases occur in adults; older patients have worse outcomes 
• Bell clapper deformity – bilateral in 80% of patients
• Prior episode of torsion 
• Family history
• Trauma (can be minor)

Clinical Presentation:

• Sudden/severe testicular pain
  • Often unilateral, may radiate.
  • Pain can be intermittent.
  • 84-90% have testicular pain.
  • May start within a few hours of a minor trauma or wake them from sleep.
• Abdominal/flank pain – 20% ONLY have this complaint (check this testicles in a male patient with abdominal/flank pain).
• Diffuse scrotal/testicular tenderness, swelling, and erythema (a later sign).
• Nausea and vomiting.
• Difficulty urinating – 12% of cases.

Exam:

• Tender, swollen, firm, high riding testicle (OR 18-58.8 for diagnosis).
• Long axis of the torsed testicle may be oriented horizontally.
• Erythema of the scrotal wall and reactive hydrocele are late findings.
• Hard, tender knot in spermatic cord.
• Cremasteric reflex 
  • Classically absent/diminished in torsion, but cannot definitively rule in or out torsion. 
  • In one study, ~40% of torsion patients had a cremasteric reflex. 
  • 30% of patients with normal testicles will not have a cremasteric reflex.  
• Prehn’s sign (pain relief with elevation of the testicle)
  • Classically associated with epididymitis.
  • ⅓ of kids with torsion had a positive Prehn’s sign.
  • Don’t rely on the Prehn’s sign in your evaluation of torsion.

The Testicular Workup for Ischemia and Suspected Torsion (TWIST) scoring and risk stratification system (TWIST SCORE):

• 2013 original study and recommendations:
  • 0-2 points = LOW RISK, not torsion – consider other diagnosis
  • 3-4 points = Intermediate Risk – need ultrasound
  • 5-7 points = High Risk – high likelihood of torsion, call urology
  • Found 100% negative and positive predictive values using a cutoff of 2 points for low risk and 5 points for the high risk group.  
• 2016 validation study 
  • 0 points for low risk, 1-5 for intermediate risk and 6-7 for high risk.
• 2022 meta-analysis 
  • 0-2 as low risk and ≥5 or higher as high risk =  AUC of 0.924.
  • 0 as low risk, 1-5 points as intermediate risk and ≥6 points as high risk  = 99.5% sensitive. 
• Keys:
  • Order the ultrasound in a patient with testicular pain, especially with any TWIST score >0.
  • Minimal if any harm to patients by obtaining ultrasound.
• If you are going to use the TWIST score, make sure your department and your urologists are comfortable with it. Figure out what score you’ll use for low risk and high risk. 

Evaluation:  

• US with doppler is the first line imaging modality.  
  • Enlarged, hyperemic testicle with ↑ echogenicity, irregular contour & reactive hydrocele (note: latter might not appear for several hours).
  • Assess for no flow or decreased flow velocity in intratesticular arteries.
    • Power doppler preferred over color doppler as it is sensitive to low-flow states. Color doppler provides flow direction, which we do not care about in torsion.
  • Other signs on US:
    • Whirlpool sign – twisted spermatic cord with spiral pattern.
    • Pseudomass –  congested epididymis/vas deferens/vascular bundle below twisted spermatic cord.
    • Horizontally lying testicle.
  • Sensitivity 86-98%; specificity 90-98%.  
  • POCUS is not as accurate.
  • Even with a normal ultrasound, if the history/exam are concerning – call urology.
• Degrees of torsion:
  • Complete –  testicle twists ≥360^o, US usually shows absence of intratesticular flow.
  • Incomplete – testicle twists <360^o. Flow is decreased but present.
  • Intermittent – testicle torses and detorses.  

Management:

• Definitive therapy = surgical exploration, detorsion, and fixation of the testicle.
  • Contralateral orchiopexy due to risk of torsion of the other testicle .
  • Orchiectomy necessary if necrotic.
  • > 90% salvage rate within the first 6 hours.
  • Systematic review shows testicular survival was 97.2% at 0-6 hours, 79.3% at 7-12 hours, 61.3% at 13-18 hours, 42.5% at 19-24 hours, 24.4% at 25-48 hours, and 7.4% at greater than 48 hours. 
  • Another study found that every 10 minute delay to detorsion increased the risk of testicular nonviability by 5%. 
• If no urologist, attempt manual detorsion:
  • Success rate of 30-70%.
  • Manual detorsion is classically described as “opening the book”.
    • Face the patient, grab the affected testicle between your thumb and index finger, and then rotate the testicle laterally towards the ipsilateral thigh.
    • Some studies suggest the average degree of torsion is 720 degrees, so you may need to “open the book” a couple times.  
    • If no improvement or worsening pain, rotate in the opposite direction as if you are “closing the book”.
  • Analgesia, not sedation, is necessary.
  • Repeat ultrasound after manual detorsion to look for normal blood flow.
  • All patients need admission for exploration and orchiopexy/orchiectomy.

Medicolegal considerations:

• 3rd most common cause of malpractice suits in males 12-17 years old & average settlement of $60,000.
• Missed diagnosis often due to: atypical presentation, torsion not considered, or no testicular exam was done.
• Document consideration of torsion in males with abdominal pain.

Pearls:

• There are findings on history and exam that suggest torsion, but there is no single element that can exclude it including the cremasteric reflex.
• The TWIST score has been validated and can help guide clinical decision making in patients presenting with acute testicular pain.
• US with doppler is the first line imaging modality.
• The diagnosis is time sensitive. Patients have the best outcomes when detorsion occurs in the first 6 hours after symptom onset.
• Definitive management is surgical exploration and detorsion, but if there is going to be a major delay and there is confirmed diagnosis, go with manual detorsion.

References:

1. Rosenberg H, Long B, Keays M. Just the facts: assessment and management of testicular torsion in the emergency department. CJEM. 2021 Nov;23(6):740-743. doi: 10.1007/s43678-021-00189-6. Epub 2021 Aug 18. PMID: 34406643.
2. Mellick LB, Sinex JE, Gibson RW, Mears K. A Systematic Review of Testicle Survival Time After a Torsion Event. Pediatr Emerg Care. 2019 Dec;35(12):821-825. PMID: 28953100.
3. Barbosa JA, Tisea BC, Barayan GA, Rosman BM, Torricelli FCM, Passerotti CC, Srougi M, Retik AB, Hguyen HT. Development and initial validation of a scoring system to diagnose testicular torsion in children. J Urol. 2013;189(5):1859–64. PMID: 2310800
4. Sheth KR, Keays M, Grimsby GM, et al. Diagnosing Testicular Torsion before Urological Consultation and Imaging: Validation of the TWIST Score. J Urol. 2016;195(6):1870-1876.  PMID: 26835833
5. Qin KR, Qu LG. Diagnosing with a TWIST: Systematic Review and Meta-Analysis of a Testicular Torsion Risk Score. J Urol. 2022;208(1):62-70. PMID: 35238603 
6. Gold DD, Lorber A, Levine H, et al. Door To Detorsion Time Determines Testicular Survival. Urology. 2019;133:211-215.  PMID: 31408640