Appendix Testis Torsion

Get CMETestis Appendix TorsionAcute scrotal pain will always grab both patient’s and providers’ attention, appropriately.  We have already discussed the most feared cause of acute scrotal pain – Testicular Torsion. While there are many other causes of inguinal and scrotal pain (ex, varicocele, inguinal hernia), one of the common causes is Torsion of the Appendix Testis.


Appendix Testis: What is that?

  • There are actually 4 identified testicular appendages, but appendix epididymis and  appendix testis or the most commonly encountered.
  • Appendix testis is located in the groove between testis and the epididymal head at the upper pole of the testis.
  • The appendix testis is pedunculate and susceptible to torsion.
  • Torsion of the appendix testis is a common cause of acute scrotal pain in children. [Boettcher, 2013Sakellaris, 2008]


Appendix Testis: Don’t Get it Twisted

  • Etiology of torsion is unknown.
  • Usually occurs in boys 7-14 years of age.
  • More common than epididymitis in children.
  • Torsion of the appendix testis can lead to necrosis of it.
    • The necrotic tissue will lead to local inflammation and, thus, mimic epididymitis.  [Boettcher, 2013]
    • Inflammatory cells infiltrate the twisted appendix testis and are a marker of progression of the disease, not infection. [Rakha, 2006]



  • Clinical History and Exam are helpful, but not conclusive
    • “Classic” signs:
      • Localized tenderness at the superior pole
      • Blue Dot sign
      • Preserved cremasteric reflex
    • Findings that favor Epididymitis: [Boettcher, 2013]
      • Dysuria
      • Painful epididymis
  • Ultrasound can be helpful in making the diagnosis. [Lev, 2014; Yang, 2005]
    • Findings consistent with torsion of appendix testis:
      • Size of 5 mm or greater
        • May see hyperechogenic mass between epididymal head and upper pole of the testis.
        • Often associated with enlarged epididymis and hydrocele.
      • Spherical shape
      • Increased periappendiceal blood flow
    • Findings more consistent with epididymitis:  [Boettcher, 2013]
      • Altered epididymal echogenicity
      • Increased peritesticular perfusion on the affected side
    • Often used as means to evaluate for testicular torsion.
      • Ultrasound is not perfect in ruling-out testicular torsion.
      • Recall that normal blood flow does not completely exclude the possibility of testicular torsion. [Sakellaris, 2008]



  • NSAIDs
  • Restricted activity (“Sorry, no soccer or football this weekend boy.”)
  • Cool Sitz baths
  • Antibiotics are not required.
    • Obviously, this seems intuitive, but often the U/S may indicate findings consistent with epididymitis/orchitis so you may be inclined to give abx.
    • Antibiotics for epididymitis can be reserved for boys with: [Boettcher, 2013; Halachmi, 2005]
      • Recurrent infection history
      • Underlying urinary tract abnormality
      • Signs of puberty
  • Very rarely will surgical excision be required for pain control.



Lev M1, Ramon J1,2, Mor Y1,2, Jacobson JM2,3, Soudack M2,3. Sonographic appearances of torsion of the appendix testis and appendix epididymis in children. J Clin Ultrasound. 2015 Oct;43(8):485-9. PMID: 25704247. [PubMed] [Read by QxMD]

Boettcher M1, Bergholz R, Krebs TF, Wenke K, Treszl A, Aronson DC, Reinshagen K. Differentiation of epididymitis and appendix testis torsion by clinical and ultrasound signs in children. Urology. 2013 Oct;82(4):899-904. PMID: 23735611. [PubMed] [Read by QxMD]

Sakellaris GS1, Charissis GC. Acute epididymitis in Greek children: a 3-year retrospective study. Eur J Pediatr. 2008 Jul;167(7):765-9. PMID: 17786475. [PubMed] [Read by QxMD]

Rakha E1, Puls F, Saidul I, Furness P. Torsion of the testicular appendix: importance of associated acute inflammation. J Clin Pathol. 2006 Aug;59(8):831-4. PMID: 16569689. [PubMed] [Read by QxMD]

Halachmi S1, Toubi A, Meretyk S. Inflamation of the testis and epidididymis in an otherwise healthy child: is it a true bacterial urinary tract infection? J Pediatr Urol. 2006 Aug;2(4):386-9. PMID: 18947641. [PubMed] [Read by QxMD]

Yang DM1, Lim JW, Kim JE, Kim JH, Cho H. Torsed appendix testis: gray scale and color Doppler sonographic findings compared with normal appendix testis. J Ultrasound Med. 2005 Jan;24(1):87-91. PMID: 15615932. [PubMed] [Read by QxMD]


Sean M. Fox
Sean M. Fox
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