Intra-abdominal testicular torsion in a horse without signs of colic.

This study recounts the case of a 5-year-old horse that underwent cryptorchidectomy due to an undescended testis, which was found to be necrotic because of testicular torsion. It suggests that unobserved intra-abdominal testicular torsion could cause monorchidism, a condition where only one testicle descends, in some horses.

Background

• The research focuses on the medical case of a 5-year-old Quarter Horse stallion with no signs of abdominal pain or any other physical abnormalities except for an undescended left testis.

Procedure and Findings

• The horse was admitted for cryptorchidectomy, a surgical procedure to remove an undescended testis. It was performed using an inguinal approach, with the entry point being in the groin area.
• During the procedure, it was observed that the tail of the epididymis, the tube that carries sperm, was in the inguinal canal, a passage in the anterior abdominal wall. Moreover, the testis was adjacent to the internal inguinal ring, which is part of the passageway in the lower anterior abdominal wall through which the spermatic cord passes.
• The testis was found to be dark reddish purple to black, a result of testicular torsion occurring at the body of the epididymis. Testicular torsion is a serious condition where the spermatic cord, which provides blood flow to the testicle, gets twisted and cuts off the blood supply.

Consequences

• Upon histologic examination, the tissue analysis of the left testis showed it to be necrotic, indicating a death of cells in an organ or tissue due to lack of blood supply.
• The lack of abdominal pain, despite such a serious condition, which typically causes severe discomfort, was peculiar in this case. This particular case suggests testicular torsion developed without abdominal pain, which eventually led to the necrosis of the affected testis.

Implications and Future Considerations

• If the cryptorchidectomy had not been carried out, it is probable that the horse would have been discovered to be monorchid, which means having only one descended testicle.
• The research suggests unrecognized intra-abdominal testicular torsion might be a cause for monorchidism in some horses. This is significant as it could provide a new understanding in the causes of monorchidism, ultimately enhancing diagnosis and treatment of similar cases in the future.