Testicular torsion is defined as the twisting or torsion of the spermatic cord causing severe pain and ischemia of the testicle. Torsion are classified into two groups: either intravaginal or extravaginal. Intravaginal torsion, which is most common in juvenile and adolescent boys, occurs within the tunica vaginalis. Extravaginal torsion, which is seen primarily in neonates, is seen in undescended testicles and has torsion of the testies, spermatic cord, and the process vaginalis. According to one text, the incidence of torsion of the testicles is one in 160 males [1•]. The prevalence of this condition is from birth to around 60 years old, with the peak age of occurrence around 14 years old. Approximately two thirds of cases occur between 10 and 20 years of age. The second highest age group is neonates. Torsion rarely occurs after 30 years of age.
The causes of torsion may be idiopathic or traumatic. Though the majority of them are idiopathic, only 20% have a traumatic cause [2•]. Over one third of the patients diagnosed with testicular torsion have had an episode of previous testicular pain. For the testicles to torse, they must have an incomplete, ruptured, or absent fixation to the scrotal sac . Many patients are noted during surgical treatment to have a congenital aberrancy of the tunica vaginalis inserted high on the spermatic cord, and a redundant mesorchium that may permit increased mobility and torsion of the spermatic cord. Generally the aberrancy is bilateral, in both testicles.
In the last trimester of pregnancy the intra-abdominal testes descend into the scrotum through an outpouching of the peritoneum called the process vaginalis. As the abdominal portion of the process vaginalis closes the descending portion becomes a potential space called the tunica vaginalis. This potential space is where fluid can accumulate. The tunica vaginalis covers the anterior two thirds of the testis. The epididymis is positioned posterior and lateral to the testis. These two important landmarks are important to identify as part of the scrotal examination.
There are two common embryonic testicular remnants: the appendix testis and appendix epididymis. The appendix epididymis is attached to the head of the epididymis and the appendix testis attached to the upper pole of the testis.
When the testicle twists, it usually twists in the direction of lateral to medial. The range of torsion goes from 90° to 180° (incomplete torsion) to 540° to 720° (complete torsion). Depending on the amount of torsion, vascular compromise of the testicle can occur within 6 hours [1•] or up to 12 hours [2•]. Once enough vascular compromise occurs to the testicle, testicular infarction will occur, which leads to atrophy and decrease in sperm production, thus possibly affecting fertility.
Signs and Symptoms
Most patients describe the sudden onset of unilateral testicular pain and tenderness, often followed by scrotal swelling. Around 50% of patients with torsion complain of nausea and vomiting [1•], around 25% complain of fever [1•]. Most patients do not have symptoms of dysuria, penile discharge, frequency, or urgency with torsion. The cremasteric reflex is often absent on the affected side in torsion. The scrotum usually becomes eyrthematous, edematous as time progresses. Prehn's sign, which is elevating the testicle to help differentiate between epididymitis and torsion, is considered unreliable. With elevation those patients with epididmyitis will feel some relief of their pain whereas those with torsion will notice no difference or a worsening of their pain as the torsion worsens.
Epidiymitis is another unilateral, nontraumatic testicle condition and is often high on the differential to rule out. A simple urinalysis devoid of leucocytes and a negative culture usually rules this condition out. These patients often have a tender epididymis without true testicle pain. Other causes include testicular fracture or hematoma usually associated with direct trauma. Acute scrotal masses including tumors (eg, seminomas) and nonmalignant masses such a spermatoceles, hydroceles, and hematolceles can sometimes present as a unilateral, painful testicle. Varicoceles, which a natural prevalence of around 10% to 15%, are generally painless. Because of the predilection to occur in the pediatric and adolescent population, Henoch-Schonlien purpura should be considered. These patients with most usually present with a purpruritic rash, abdominal and lower extremity pain, in addition to testicular pain. Their sedimentation rate, leukocyte count, and IgA levels are often elevated, whereas their International Normalized Ratio, platelets, and compliment levels are normal. An incarcerated or strangulated inguinal hernia can also present as scrotal pain and swelling. There may be bowel sounds in the scrotum if not totally strangulated, but imaging is necessary to often rule this out. Torsion of the testicular appendix, as opposed to the entire testicle, can also mimic a true testicular torsion. Once again, imaging is necessary to discern this condition. Lastly, a scrotal abscess may also present as unilateral testicular pain and swelling.
Acute testicular pain should be considered testicular torsion until proven otherwise. Torsion of the spermatic cord is a surgical emergency that can lead to parenchymal damage in as soon as 4 hours after occlusion of the testicular vessels [4•]. Whenever torsion is suspected prompt surgical exploration is required. The physical examination will change over time as severe scrotal swelling and hydrocele formation may make it difficult for the examiner to palpate anatomic landmarks. There should be a brief but thorough evaluation of the scrotum, testis, epididymis, inguinal region, spermatic cord, abdomen, and penis. The examiner should also assess the patient's general behavior, level of distress, and his ability to ambulate and communicate.
Torsion can sometimes be confused with epididymitis or torsion of the appendix testis. Usually there are several important physical findings to help with differentiation. Early on in testicular torsion the testicle is swollen, firm, and exquisitely tender. The testis can be asymmetrically high-riding as the torsion causes the cord to shorten and the long axis to change from vertical to horizontal. This is known as the “bell-clapper” deformity. The left testicle naturally lies slightly lower than the right.
Epididymitis will have no axial change and the testis is usually softer and less tender in its earlier course. The epididymis, which lies posteriorly and runs along the inferior to superior pole, may be swollen and very tender to palpation. Also, there may be spermatic cord tenderness, which is usually not tender in torsion. There may be reactive swelling and hydrocele formation. Prehn's sign can help when the clinical picture is unclear. The scrotum in question is elevated, taking pressure off the spermatic cord. In epididymitis, there may be relief with elevation but no relief with torsion patients. Pain for over 12 hours with a normal appearing testis is generally not torsion. Testicles in both torsion and epididymitis will be swollen and erythematis after 24 hours.
The cremasteric reflex should be evaluated in all patients with testicular pain. This is done by gently stroking the superior medial thigh in a downward motion while observing the scrotum. The normal response in is a contraction of the cremasteric muscle that elevates the scrotum and testis on the side stroked. This reflex is practically universal in the pediatric population between the ages of 30 months and 12 years . This reflexes is absent in testicular torsion but present in torsion of the appendix testis .
Torsion of the appendix testis can also lead to a reactive hydrocele. Usually the pain is localized to the anterosuperior region over the appendix and comes on more gradually. Sometimes infarction with subsequent necrosis of the appendix testis will leave a “blue dot” .
Laboratory results are generally not helpful with the diagnosis of torsion. The urinalysis is usually normal and 50% of patients have a leukocytosis on complete blood counts .
If a testicular torsion diagnosis can be made clinically the patient should be taken emergently for surgical exploration. If the history and exam is equivocal, high-frequency color Doppler ultrasonography is the preferred imaging choice . Sensitivity is between 86% and 100% and specificity is 97% to 100% [1•]. The diagnosis is made by looking for decreased or absent testicular profusion. Epididymitis and recently detorsed testis will show increased blood flow. Typically, the healthy testicle is scanned first to set the gray scale and for comparison with the affected side. The testes are scanned in both the long and transverse axis. Ultrasound can also determine the size and other pathology of the scrotal contents including an enlarged appendix testis or scrotal fluid.
A radionuclide testicular scintigraphy with 99mTc can also be performed but it takes longer and is not available in all institutions. Nucleotide scans have a 98% and 100% sensitivity and specificity respectively [1•]. All imaging modalities in infants are limited due to the small size of the testicular vessels and minimal blood flow to the testes . If a patient has only epididymitis, then usually the affected side will show an increased flow. The gold standard is still exploratory surgery and should be done even if the radiologic study is negative if the clinical findings are consistent with torsion [4•].
If emergent surgery service is not immediately available then manual detorsion should be attempted with the proper sedation and analgesia. The scrotum should be cooled and cord block with lidocaine. The testis may have rotated as far as 720° and usually rotates toward the midline [4•,7]. The degree of rotation usually increases with the age of the patient. The examiner should attempt to rotate the testis laterally toward the thigh. Successful detorsion can bring immediate relief and the testis resumes a vertical lie and lengthening of the cord. If there is no relief rotation should be made in the opposite direction (toward the midline) because the testis rotates laterally one third of the time . Surgery is still required if manual reduction is successful.
All testicular torsions need to have surgical exploration of the affected and contralateral testis. Orchidopexy, three- to four-point fixation with nonabsorbable sutures [2•] of both testes, should be done to avoid recurrent torsion. Nonviable testes should be removed. Testes that appear to have marginal viability can be detorsed to re-establish blood flow, warmed, and then re-evaluated [4•].
Prognosis depends on age of the patient and duration of torsion. In general, younger children do better than teenagers and adults and the longer the torsion the greater the damage . If the torsion is resolved within 4 to 6 hours complete recovery can be expected. Testes are not viable after 24 hours of torsion and only have minimal viability at 12 hours (20%) .
Missed or delayed diagnosis can led to necrotic and gangrenous testes, testicular atrophy, infertility, and abnormal spermatogenesis. Marginal testes that are saved can theoretically lead to infertility. The damaged testis can have a breakdown of the blood-testis barrier, exposing germ cells to the immune system. This can lead to production of antisperm antibodies [4•]. Unfortunately salvaged testes can atrophy up to 3 years post-torsion [2•]; however, most urologists will save marginal testes [4•].
Though it is important to always have a wide differential diagnosis when investigating an acute problem such as testicular pain, one must rapidly progress toward the proper treatment if testicular torsion is suspected, because the viability of the testicle decreases within hours after the torsion occurs. History of sudden-onset, often nontraumatic unilateral testicular pain is the most common complaint. Epididymitis is often confused with testicular torsion, use of the Prehn's sign may be helpful, but should always be followed with imaging to confirm the diagnosis. The ultrasound of the testicle with flow Doppler is still the preferred diagnostic treatment tool after a thorough history and physical examination has been completed. Most torsed testicles require will require bilateral orchidopexy.
References and Recommended Reading
Papers of particular interest, published recently, have been highlighted as: • Of importance, •• Of major importance
1.• Black TL: Testicular torsion.Five-minute Sports Medicine Consult.
Baltimore: Lippincott, Williams & Wilkins; 2001:1058–1059.
A quick, concise, rather up-to-date reference for the clinician.
2.• Newton E: Testicular torsion.Five-minute Clinical Consult.
Baltimore: Lippincott, Williams & Wilkins; 2000:546–547.
A quick, concise, rather up-to-date reference for the clinician.
3. Mellion M, Walsh W, Shelton G: The Team Physician's Handbook,
edn 2. Philadelphia: Mosby; 1997:285.
4.• Walsh P, et al.
: Acute scrotum.Campbell's Urology,
edn 8. Edited by Campbell MF, Walsh PC, Retik AB. Philadelphia: Elsevier Science; 2002:2379–2384.
Nice surgical text, but with good practical information. In addition, explains the surgical procedures well.
5. Caesar RE, Kaplan GW: The incidence of the cremasteric reflex in normal boys.J Urol
1994, 152(2 Pt 2): 779–780.
6. Kadish H: Pediatric surgical emergencies: the tender scrotum.Clin Pediatr Emerg Med
7. Eyre RC: Evaluation of the acute scrotum in adults.
8. McCollough M, Sharieff GQ: Abdominal surgical emergencies in infants and young children.Emerg Med Clin North Am
9. Dogra V, Bhatt S: Acute painful scrotum.Radiol Clin North Am
10. Brenner JS, Aderonke O: Testicular and scrotal masses in children and adolescents.