Testicular torsion

Risk factors

• Two peaks of incidence:
  • Perinatal period
    • Described as 'extravaginal' torsion - implying that torsion occurs due to failure of tunica vaginalis to attach to the surrounding structures, and is therefore torsion of the spermatic cord as a whole
    • Some torsions can also be intravaginal in this period
    • Urgent exploration and contralateral fixation should occur, as salvage is still possible
  • 11-25yo

Pathophysiology

• Tends to twist anteriorly and towards the midline, so that viewed from below the right testis turns clockwise and the left anticlockwise
• Main factors determining damage:
  • Extent of twist (720 degrees more rapid ischaemia than 360)
  • Duration of ischaemia (nearly 100% chance of salvage if detorted within six hours, compared to 20-61% at 12 hours, and 20% salvage at 24 hours)
• Occasionally detorts spontaneously, especially in adolescents
• One of the following abnormalities may be present:
  • High investment of tunica vaginalis causes the testis to hang freely within the tunica like a bell-clapper within a bell - typically bilateral, most common cause in adolescents. Apparently seen in 90% of torsion presentations.

• Inversion of the testis
• Separation of epididymis from the body of the testis permits torsion on a pedicle that connects the testis with the epididymis

History -

• sudden onset, severe, constant, unilateral testicular pain in a young man
• May be preceded by trauma or exercise
• Much less common pre-pubertal - in this age group, more reasonable to order an USS and go from there, given torted appendage is main differential

Exam - generally exquisitely tender testis, may be high-riding or transverse lie, may be oedematous, cremasteric reflex is not that sensitive. May feel tender twisted cord. Erythema of scrotum may be absent early. Elevation of testis may worsen pain or not help, whereas it is supposed to improve the pain of epididymo-orchitis.

• Cremasteric reflex: afferent femoral branch of genitofemoral, efferent genital branch of genitofemoral.

Manual detorsion

• Potentially there is a role for it in some situations
• Pain should significantly improve afterwards
• Must proceed to exploration and fixation regardless

Colour doppler USS (should not delay exploration if clinical concern for torsion)

• User-dependent - may be less accurate than clinical
• Whirlpool sign - high risk for twisted cord
• High-risk false negative, particularly in early torsion - volume and echogenicity can be normal for first three hours
• Overall sensitive and specific after this period
• Can see increased blood flow to epididymis after a torsion event

DDx: epididymitis, trauma, tumour

• Idiopathic scrotal oedema
  • Usually aged 3-6yo
  • Swelling is prominent feature - early swelling, which can be seen in perineum/inguinal region or base of penis
  • Generally bilateral
  • Also have pain, but not as bad, or may be pain-free
  • Skin can be tender but testis and cord are normal
  • Apparently often seen in atopic/anaphylactic kids - occasionally a/w eosinophilia
  • Usually subsides within a day or two but may recur
• Torted testicular appendage
  • Usually 3-11yo
  • Most common structure to twist is pedunculated hydatid of Morgagni (testicular appendage)
  • Palpate carefully for an exquisitely tender nodule at the upper pole, while body of testis is non-tender
  • Transillumination may reveal blue dot sign
  • Can still see quite prominent scrotal signs - swelling, erythema
  • NSAIDs and will settle but can take up to a week
  • Does not need admission
• Torted epididymal appendage
  • Superiorly
• Acute epididymo-orchitis
  • Unilateral epididymo-orchitis is rare in children, but when it occurs, it is probably associated with UTIs and anomalies of the urinary tract
  • More common in older patients, often associated with dysuria
  • Elevation of testis may reduce pain.
• Mumps
  • Rarely occurs before puberty
  • Usually bilateral
  • Usually 3-7 days after onset of parotitis
  • Check for elevated salivary amylase or real-time mumps PCR
  • Cord not thickened, and is often bilateral
• Inguinal hernia
  • Rare mimic - small tense strangulated hernia compressing the cord and causing compression of the pampiniform plexus

Aim for exploration within 6 hours, however even if >6 hours since onset, still worth rushing

Exploration:

• Ask for 15 blade, bipolar diathermy (although can use monopolar), 3/0 Prolene, 4/0 undyed Vicryl Rapide, Opsite spray
• 5cm median raphe incision, then sharply dissect layer by layer directly onto the bunched up testicle with your hand underneath. Usually get a gush of reactive hydrocoele before reaching testicle - once this occurs, means you have opened tunica vaginalis, change to Metz and divide more of tunica vaginalis along the length of skin incision. Divide generously, because it's hard to free this up more once the testis out.
• If unsure of viability, an incision to testicular parenchyma should give good bleeding in a viable testis. If no bleeding after 10 minutes, non-viable testis, should be removed (ligate cord within the scrotum with 0 Vicryl transfixion sutures and excise testis).
• Evert testis from tunica vaginalis and fix with 3x 3/0 sutures (ideally something permanent but soft, like Ethibond) within the tunica albuginea and the lateral scrotal wall, at the upper and lower poles and the equator.
• Torsion of appendix testis - excise cyst, no need to explore contralateral side
• Meticulous haemostasis
• Close tunica albuginea with running 4/0 undyed Vicryl, then local anaesthetic to dartos, then close skin/dartos together with interrupted 4/0 Vicryl.
• Opsite spray
• Supportive underwear

Complications

• Haematoma
• Infection
• Infertility - negligible impact, even with orchidectomy/orchidopexy