Torsion of the testis may more accurately be called torsion of the spermatic cord. It causes occlusion of testicular blood vessels and, unless prompt action is taken, rapidly leads to ischaemia, resulting in loss of the testis (germ cells are the most susceptible cell line to ischaemia).
- Testicular torsion is a common urological emergency among adolescent boys and young men.
- The condition typically occurs in neonates or post-pubertal boys but can occur in males of all ages.
- The left side is more commonly affected than the right.
- Bilateral cases are rare.
Two types of testicular torsion may occur: intravaginal and extravaginal. Intravaginal torsion is secondary to the lack of normal fixation of the posterior lateral aspect of the testes to the tunica vaginalis. This results in the testis being free to swing and rotate within the tunica vaginalis of the scrotum. This defect is referred to as the 'bell-clapper deformity'. This occurs in 12% of all males and is bilateral in around 40% of cases.
Extravaginal torsion occurs more often in neonates and occurs in utero or around the time of birth before the testis is fixed in the scrotum by the gubernaculum. Consequently, both the spermatic cord and the tunica vaginalis undergo torsion together, typically in or just below the inguinal canal.
A high insertion of the tunica vaginalis produces a 'bell-clapper testis' with a horizontal lie rather high in the scrotum. This lie, with the long axis in the horizontal rather than the vertical plain, is usually bilateral. There may be a genetic factor in some cases of torsion.
Acute swelling of the scrotum in a boy indicates torsion of the testis until proven otherwise. In approximately two thirds of patients, history and physical examination are sufficient to make an accurate diagnosis.
- There is typically sudden, severe pain in one testis.
- There may be lower abdominal pain and, in any boy presenting with abdominal pain, the testes should be checked.
- It often comes on during sport or physical activity.
- There is quite often a history of previous, brief episodes of similar pain. This is presumably torsion that corrected itself.
- Nausea and vomiting often occur.
- Occasionally, the symptoms are milder and less acute.
- Easing pain is not necessarily a good sign of spontaneous resolution. Pain also eases as necrosis sets in.
- A history of recurrent attacks of severe pain that resolved spontaneously might suggest intermittent testicular torsion and de-torsion.
Examination is often helpful but normal findings should not preclude further investigation if clinical suspicion is high.
- There is usually reddening of the scrotal skin.
- There is a swollen, tender testis retracted upwards.
- Lifting the testis up over the symphysis increases pain, whereas in epididymitis this usually relieves pain.
- In the early stages, the epididymis may be felt in an abnormal anterior rather than typical posterior position but this depends upon the degree of torsion that may be from 180-720°. Later, gross swelling prevents this finding.
- The testes on both sides are characteristically in the 'bell-clapper position' with a horizontal long axis.
- Looking for absence of the cremasteric reflex is a simple method with 100% sensitivity and 66% specificity for testicular torsion.
- The cremasteric reflex (L1/L2 spinal nerves) is elicited by gentle pinching or stroking of the inner thigh while observing the scrotal contents.
- If the torsion occurs prenatally, the baby is born with a firm, hard, non-transilluminable scrotal mass. There are no symptoms. The scrotal skin is usually fixed to the underlying necrotic testis.
- Torsion of testicular or epididymal appendage:
- This usually occurs in boys aged between 7 and 12 years.
- Systemic symptoms are rare.
- There is usually localised tenderness but only in the upper pole of the testis.
- Occasionally, the 'blue dot sign' is present in light-skinned boys (ie a tender nodule with blue discoloration on the upper pole of the testis).
- Epididymitis, orchitis, epididymo-orchitis:
- These conditions most commonly occur from the reflux of infected urine or from sexually acquired disease caused by gonococcus and Chlamydia spp. Hence, they tend to affect an older age group.
- NB: patients with acute epididymitis usually experience a tender epididymis, whereas patients with testicular torsion are more likely to have a tender testicle.
- Swelling is usually painless.
- The scrotum will transilluminate.
- Incarcerated hernia:
- This may be diagnosed by careful examination of the inguinal canal.
- Testicular tumour:
- Scrotal enlargement occurs more slowly.
- It is only rarely accompanied by pain. Typically, the normal slightly delicate sensation of the testis is absent.
- There is swelling of the parotid glands in mumps.
- Mumps orchitis is rare before puberty.
- The most important investigation is ultrasound integrated with colour Doppler.
- The use of Doppler ultrasound may reduce the number of patients with acute scrotum undergoing scrotal exploration but it is operator-dependent and can be difficult to perform in prepubertal patients.
- Doppler ultrasound may also show a misleading arterial flow in the early phases of torsion and in partial or intermittent torsion. In addition, persistent arterial flow does not exclude testicular torsion.
- Scintigraphy and dynamic contrast-enhanced subtraction magnetic resonance imaging (MRI) of the scrotum may be used when diagnosis cannot be excluded from history, physical examination and ultrasound.
- Urinalysis may be helpful in borderline cases, to exclude urine infection and epididymitis. However, an abnormal urinalysis does not exclude testicular torsion.
- However, if clinical suspicion is high, surgical intervention should not be delayed for the sake of further investigation.
- All cases of acute testicular pain are due to torsion until proved otherwise. If torsion is suspected after a prompt clinical assessment, a scrotal exploration should be carried out without delay.
- An immediate referral must be made to the emergency urology or surgical team. Before further assessment, food should be withheld and patients provided with adequate analgesia.
- It may be possible to reduce the torsion manually. It should initially be done by outwards rotation of the testis unless the pain increases or if there is obvious resistance. Success is defined as the immediate relief of all symptoms and normal findings at physical examination.
- Bilateral orchiopexy is still required after successful detorsion. This should not be done as an elective procedure but rather immediately following detorsion.
- Testicular torsion is an urgent condition, which requires prompt surgical treatment. The two most important determinants of early salvage rate of the testis are the time between onset of symptoms and detorsion, and the degree of cord twisting.
- After 24 hours there is controversy as to whether the testis should be removed or fixed, even if it shows some viability, as there is some evidence that orchiectomy is more likely to preserve the function and fertility of the ipsilateral testis.
- If the testis is viable then orchidopexy is usually performed to prevent recurrence, although there is no consensus about this, as the evidence base is small.
- Whether the affected testis is removed or conserved, the contralateral one should undergo orchidopexy, as the risk of recurrence on the other side is otherwise high.
- A baby born with testicular torsion should have the affected testis removed (because it is always non-viable) and orchidopexy of the other side (because bilateral torsion is common).
- Complications of an untreated or delayed torsion include infarction of the testicle with subsequent atrophy, infection and cosmetic deformity.
- Subfertility and infertility may occur. This is caused by the cut-off of blood supply and also by the post-ischaemia-reperfusion injury that is caused after the detorsion when oxygen-derived free radicals are rapidly circulated within the testicular parenchyma.
- However the absence of one testis usually has no significant effect on fertility, provided that the other testis functions normally.
- Overall subfertility is found in 36-39% of men after torsion.
- The extent and duration of torsion have a major influence on both the immediate salvage rate and late testicular atrophy.
- Testicular salvage most likely occurs if the duration of torsion is less than six hours.
- If it exists for 24 hours or more, testicular necrosis is usual.
- One study reported successful harvesting of semen from a subjectively dead testicle, indicating that salvage and cryopreservation of semen should be attempted in all but the most hopeless cases.
- The absence of a testis may still have a significant psychological effect and so it is usual to implant a prosthesis if orchidectomy is required. This is usually delayed for six months to let inflammation subside and it is usually inserted via an inguinal incision.
- Recurrent, intermittent pain, with a 'bell-clapper' testis, requires orchidopexy.
- Delay has a considerable adverse effect on survival of the testis and late presentation is a substantial problem.
Further reading and references
Ludvigson AE, Beaule LT; Urologic Emergencies. Surg Clin North Am. 2016 Jun96(3):407-24. doi: 10.1016/j.suc.2016.02.001.
Rafailidis V, Apostolou D, Charsoula A, et al; Sonography of the scrotum: from appendages to scrotolithiasis. J Ultrasound Med. 2015 Mar34(3):507-18. doi: 10.7863/ultra.34.3.507.
Kuhn AL, Scortegagna E, Nowitzki KM, et al; Ultrasonography of the scrotum in adults. Ultrasonography. 2016 Feb 24. doi: 10.14366/usg.15075.
Guidelines on Paediatric Urology; European Association of Urology (2015)
Ta A, D'Arcy FT, Hoag N, et al; Testicular torsion and the acute scrotum: current emergency management. Eur J Emerg Med. 2016 Jun23(3):160-5. doi: 10.1097/MEJ.0000000000000303.
Woodruff DY, Horwitz G, Weigel J, et al; Fertility preservation following torsion and severe ischemic injury of a solitary testis. Fertil Steril. 2010 Jun94(1):352.e4-5. Epub 2010 Feb 13.