This week I’ll do away with discussing my higgledy-piggledy process of how these posts are created and focus, instead, on this setoning business I discovered last week.

The word seton stems from the Latin seta, which means bristle and that conjures up a gruesome image if I’m honest.

Setoning is an archaic and horrific-sounding way horsemen used to treat bone spavins and other issues horses might have. The practice of setoning is, as mentioned last week, threading a length of cotton, silk or some bristled material through the skin and underlying tissue with either end left dangling from the puncture and exit site. Each day someone was given the delightful task of grabbing each end of the suture and moving it back and forth to create irritation to the area to encourage drainage and/or act as a counterirritant.

I’m all on board for the drainage part of this idea as I’ve known one or two horses that needed this done, but it was done to treat an abscess under the skin, not as a counterirritant.

In human medicine, seton needles became popular in the 15th century. The idea behind this form of counterirritant was to create a superficial irritation to distract the body from other irritations, which would reduce the pain from the original source and speed up the healing process. I don’t feel like that makes a whole lot of sense, but several sources say the same thing, so we will just go with it.

This practice (in humans) fell out of favor by the late 1800s, likely due to the risk of germs. But since the book The Horse: Its Treatment in Health and Disease, was written in 1906, we know it was still used on horses as a counterirritant for at least several more decades. It is, in fact, still used on animals today for the purpose of managing abscesses.  

In The Horse book, setoning was paired with the practice of “firing,” which I suspected was the same as pin firing. My assumption was correct. The closest the book comes to describing “firing” is, “firing with the pointed iron may prove serviceable after a run of two or three weeks at grass in a damp meadow.” Though the description is short it does describe the modern version of pin firing. I’m unsure how vets today feel about the requirement of turning a horse out in a damp meadow.

Pin firing is often referred to as an old practice. And while we are now aware that it was used some 120 years, we can still find horses today with the tell-tale evenly spaced white dots (white hairs) down the front of their fore canon bones of this procedure. Pin firing is a form of thermocautery that includes freeze firing or any other form of blistering and/or counterirritant used in an attempt to speed up healing.

Pin firing is done with a tool that has metal points that are applied to a horse’s leg where there is pain from an injury such as a bucked shins. The points are heated, and the tool burns/cauterizes through the skin and touches the periosteum, the thin membrane that covers the bone. An iodine-based paint is then applied daily to the site to ease skin discomfort for 10 days or so.

This practice was prevalent in the racehorse world, and it was used on injuries such as bucked shins, splints, curbs and sometimes on soft tissue injuries such as bowed tendons.

It must have worked well enough, or at least was thought to, as it has been around for a very long time. This practice, now considered unethical, was recently banned at U.S. racetracks, starting with the 2022 crop of foals. This is to say the ban has only just started.

While we cringe at the thought of such treatments, it would be remiss not to point out that the practitioners in the book The Horse: Its Treatment in Health and Disease truly had the horse’s best interest at heart. I’m going to pull out some direct quotes from the book because the wording is too amazing not to share.

The below is in reference to the care of a horse with sore shins or what we today call bucked shins.

“If, however, the patient has no pressing engagement his work should be reduced to walking, with as little weight on his back as possible. In more severe attacks it is better to throw the horse out of work altogether, and apply hot bandages to the legs during a course of physic.” (Page 220)

“In all cases where horses evince the slightest signs of sore shins the weight should be promptly reduced, the pace let down to walking, and, as far as practicable, the work should be done on tan, in cold wet bandages. Many a severe attack may be warded off and horses kept in work by the early adoption of proper measures.” (Page 220)

“After an attack of this disease horses should not resume work too early, and care should be taken that the ground is soft, and the pace for a time slow. Cold wet bandages should be worn for a week or two after work has been commenced, and occasional irrigation with cold water will assist in imparting tone to the legs.” (Page 220)

The Horse: Its Treatment in Health and Disease is full of interesting old-school treatments for horses and all their issues. While some of these practices seem barbaric in nature it’s nice to know that despite it all, the care of the horse, at least by intention, was at the forefront.