Surgery STAT: Scrotal ablation for routine and cryptorchid castration in horses
EDITOR'S NOTE: SurgerySTAT is a collaborative column between the American College of Veterinary Surgeons (ACVS) and DVM Newsmagazine.
This month, Charles T. McCauley writes about scrotal ablation for routine and cryptorchid castration in horses. In January, Karen M. Tobias, DVM, MS, Dipl. ACVS, professor of small animal surgery at the University of Tennessee, discusses diagnosis and care of methicillin-resistant wound infections (MRSP).
To locate a diplomate, ACVS has an on-line directory, which includes practice setting, species emphasis and research interests ( http://www.acvs.org/VeterinaryProfessionals/FindaSurgeon/ ).
The following describes a technique for scrotal ablation in routine and cryptorchid castrations utilizing a single incision that is closed without skin suture or staples. I use this technique frequently when performing routine castration on horses. Using this technique, I see fewer postoperative complications and an earlier return to training in comparison with routine castration technique.
With the horse anesthetized, the prepuce is packed with gauze and closed with continuous suture or towel clamps. The skin surrounding and directly over the scrotum is prepared for aseptic surgery. The scrotum is grasped on the median raphe with two Allis tissue forceps positioned 6–8 cm apart (Photo 1).
If minor hemorrhage occurs, it is controlled by temporary application of hemostats. The skin surrounding the incision is loose and highly mobile, allowing the incision to be manipulated over the right or left inguinal ring to access a retained testicle. The cryptorchid testicle is located and removed using the previously described technique. Thereafter, the skin incision is manipulated over the descended testicle, which is exposed and removed.
In my practice, both the cryptorchid and normally descended testicle are removed by a routine closed castration with two minor variations. One variation is separation of the cremaster muscle away from the spermatic cord and emasculation of the muscle.
This allows a greater length of the spermatic cord to be exteriorized from the inguinal ring by eliminating the pull of the muscle on the cord. The second variation is placement of a single transfixation ligature using size 1 polydioxanone suture at the most proximal aspect of the spermatic cord, which is then emasculated distal to the ligature.
After the testicles have been removed, the deep fascia on either side of the incision and the remaining median raphe are closed using size 0 polyglactin 910 in a simple continuous pattern (Photo 3).
The skin edges are apposed using size 2-0 polyglactin 910 in a subcuticular pattern. Tissue adhesive often is applied as an added barrier to contamination; however, no skin sutures or staples are needed.
This technique minimizes the risk of post-castration eventration. Complete removal of the spermatic cord at the level of the inguinal ring and ligation of the spermatic cord reduce the risk of scirrhous cord formation.
In my hands, horses castrated by this technique typically return to full work within five to 10 days. To date I have had no complications using this technique. The primary disadvantages when using this procedure for routine castration include a longer surgical time and a modest increase in the cost of the procedure.
Dr. McCauley is an ACVS board-certified surgeon and an assistant professor of surgery in the School of Veterinary Medicine, Louisiana State University, Baton Rouge, La.
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• Rodgerson DH, Hanson RR. Cryptorchidism in horses. Part II. Treatment. Compend Contin Educ Pract Vet. 1997;19(12):1372-79.
• Adams SB, Fessler JF. Castration. In: Atlas of Equine Surgery. Philadelphia PA: WB Saunders Co, 2000:209-214.
• Palmer SE, Passmore JL. Midline scrotal ablation technique for unilateral cryptorchid castration in horses. J Am Vet Med Assoc. 1987;190(3):283-5.