Background
Torsion occurs when the spermatic cord twists and compromises the blood supply to the testicle. It occurs most commonly in the adolescent age group and can follow minor trauma. The patient typically develops acute onset severe unilateral testicular pain. The pain may also radiate to the lower abdominal with nausea and vomiting. Examination reveals a swollen exquisitely tender testicle, which is often found riding high in the scrotum.
The cremasteric reflex has 100% sensitivity and 66% specificity( the cremasteric reflex can be absent in neonates and in people with neurological disorders).
The cremasteric reflex (L1/L2 spinal nerves) - gentle pinching or stroking of the inner thigh while observing the scrotal contents. The normal response, owing to shared innervations, is for the cremasteric muscle to contract, resulting in elevation of the ipsilateral testicle. Scrotal elevation relives pain in epididymo-orchitis but not in torsion (Prehn’s sign). This sign may be difficult to test reliably in children.
Management
This requires an urgent urology consult. If the diagnosis of torsion is suspected surgical exploration is necessary. The spermatic cord must be untorted within 6 hours if the testicle is to be saved. Whether or not the testicle has undergone torsion it should be sutured down to the scrotal skin to preclude any subsequent torsion and any uncertainty over the diagnosis should the pain recur. Once the testicle has been surgically tacked down it should never twist again. The opposite testicle should also be sewn down since the anatomic abnormality that caused torsion on one side may be present bilaterally.
If, however, the testicle does not appear viable intra operatively it should be removed. It has been shown that leaving a non-viable testicle in situ will significantly decrease the patient's future fertility. This is most likely due to an autoimmune phenomenon which occurs as the body is exposed for the first time the its own sperm.
Testicular appendage
Torsion of the testicular appendages can also occur. The appendix testis is by far the most common of the appendages to twist. It presents as acute onset unilateral scrotal pain in the adolescent. Usually a tender pea-sized nodule can be palpated at the upper pole of the ipsilateral testis. If the appendix testis has infarcted, a small blue dot can sometimes be seen through the scrotal skin - blue dot sign.
Surgical exploration is usually required. If an infarcted appendix is found it should simply be excised.
Differential Dx
The differential diagnosis includes Epididymo-orchitis.