Traumatic Testicular Dislocation: Why and how not to miss this rare occurrence?

A 34-year-old male self-presented to A&E 16 hours after a 70mph collision on his motorbike into the back of a stationary vehicle, complaining of pain in his right chest, thigh and groin region with corroborating ecchymosis and abrasive injuries. 

The patient had a CT head, C-spine, thorax, abdomen and pelvis down to mid-thigh, which only revealed heterogeneous material in the right inguinal region felt to be a hematoma at the time, with no other trauma-related injuries. A urology consult regarding the right groin swelling and bruising led to a decision of conservative management with no follow-up. 

The patient presented to his GP 2 weeks later with a non-palpable right testicle, subsequently having an ultrasound, which demonstrated a partially atrophied, oedematous right testicle positioned high in the inguinal canal, with no internal vascularity. 

At this point, a urology referral was arranged, which eventually led to an elective orchidectomy, where the testicle was found to be extremely stuck down to the surrounding tissue in the inguinal canal, representative of fibrosis/scarring proceeding the acute inflammatory reaction around the testicle which likely produced the illusory appearance of an inguinoscrotal haematoma on initial reporting.

This condition can be described as traumatic dislocation of the testicle (TDT). The classic presentation is a motorcyclist involved in a road traffic accident, whose fuel tank presses on the perineum along with the scrotal sac during impact and causes the testicle to dislocate without rupture. Other reported cases involve horse riding, kicking and explosion injuries. [1] 

The first case of traumatic dislocation of the testicle was described in 1809 by Claubry [2]. Since then, there have been very few documented cases (less than 200, from 1937 to 2017) [3], possibly due to under-reporting but also likely reflecting the rarity of this complication in these clinical contexts. According to Schwartz and Faerber [4], the most common site for dislocation is the distal inguinal canal (approx. 50% of cases), followed by the pubic, pelvic, canalicular, abdominal, perineal, acetabular, and crural regions. 

Prompt intervention is essential to preventing irreversible testicular damage [5], which can subsequently deteriorate into malignant transformation [6,7]. Complications such as torsion, atrophy, ongoing pain and hypofunction can arise from the persistent lie of the testicle in higher temperatures than the scrotum (more than 4 degree Celsius) [7,8]. 

In our case, the ultrasound (performed 1-month post-trauma) confirmed a dislocated testicle with imaging features strongly suggestive of a non-viable testicle. Therefore, at this late stage, the only possible solution was an orchidectomy to prevent the long-term risk of malignant transformation. The histological results confirmed an oedematous, atrophic testicular parenchyma with separated spermatic cords showing congested vessels and the presence of Sertoli cell hyperplasia with the absence of spermatogenesis, consistent with findings of an atrophic testicle resulting from dislocation injury as opposed to a congenital cryptorchid testicle [9,10]. 

Several cases of missed TDTs have been reported in the last century, especially in the presence of other distracting or masking injuries during polytrauma cases. Based on a 2004 Chinese study of 1,967 patients over 15 years with blunt abdominal trauma, 9 had TDT, all of which were overlooked initially on physical examination [11]. 

In conclusion, patients presenting with blunt perineal injury or RTA should undergo a thorough examination, including genitals, whereby a high suspicion of injury should warrant a urological consult with ultrasound testicle. TDT's with normal testicular volume and intact vascularity on ultrasound is reassuring of no focal damage and can be managed via closed reduction or orchidopexy.  

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