Proctectomy with coloanal anastomosis in horses – a cadaveric study.

Overview

• This study developed and tested a standardized surgical technique for rectal amputation with coloanal anastomosis using horse cadavers.
• The technique aims to provide a reproducible method to manage severe rectal injuries or prolapses in horses where other repairs are not possible.

Background

• Severe rectal lacerations or extensive rectal prolapse in horses can sometimes require rectal amputation (proctectomy) when the rectum is compromised beyond repair.
• Such conditions, although rare, are surgically challenging due to the complex anatomy of the equine pelvic region and the risk of life-threatening complications.
• Current surgical options may be limited when the injury or prolapse affects the entire rectal wall, making primary repair impossible.

Objective

• The study aimed to describe and standardize a surgical technique for rectal amputation with coloanal anastomosis using an equine cadaver model.
• By doing so, the researchers sought to help surgeons better manage complex rectal disorders in live horses.

Methods

• Six horse cadavers averaging approximately 442 kg were used for the procedure.
• Each cadaver was placed in lateral recumbency (lying on their side) to simulate surgical positioning.
• The anus was everted (turned outward) using simple interrupted sutures to provide access.
• A circumferential incision was made around the anal sphincter, allowing dissection of the surrounding perirectal tissues.
• The rectum was carefully dissected and transected in four quadrants to enable controlled and precise removal of the affected segment.
• After rectal removal, the remaining rectal layers (mucosal, submucosal, and muscular) were sutured directly to the anal margin using interrupted sutures, creating a coloanal anastomosis.
• Temporary sutures used for eversion were removed after completing the anastomosis to restore the anatomy.

Results

• The average length of rectum resected was about 26.5 cm, with a range between 21 and 31 cm.
• The average surgical time required for the procedure was approximately 145 minutes, ranging from 98 to 193 minutes, reflecting technical complexity.
• The procedure was found to be anatomically feasible, indicating the surgical approach can be performed in horses.
• The technique was technically reproducible across all six cadavers, suggesting it can be standardized for clinical use.

Significance and Potential Impact

• This study provides a detailed and standardized method for rectal amputation and coloanal anastomosis in horses, which previously lacked a reliable surgical protocol.
• By demonstrating the feasibility and reproducibility of the technique in cadavers, the study lays groundwork for future clinical application in live horses with complex rectal injuries.
• Having a standardized approach could improve surgical outcomes, reduce complications, and provide horses with severe rectal disease a viable treatment option where conservative management would fail.
• This may ultimately advance veterinary surgical practice in equine medicine and improve the prognosis of severe colorectal conditions in horses.