Bringing the Sparkle Back in to Crystal's Life
I was recently approached about consulting with a dressage stable owner and his plans to purchase an eight year old Swedish warmblood mare that had been diagnosed with navicular syndrome. He was interested in just using her as a brood mare since she was approaching "middle age" and the lameness problem was "incurable". I was informed that her fantastic breeding and records in the show ring would likely make her foals highly desirable. The previous owner was selling the mare because she was unable to afford the necessary surgery that the mare needed to remain sound and usable. Her veterinarian was planning on performing a digital neurectomy on both front lower legs of the mare and has been in touch with this potential new owner about following through with the necessary procedure. This stable owner decided to purchase this unsound eight year old mare at a much reduced price, and has been in consultation with me from the time she stepped foot on his property. This was six and a half mo
nths ago. He has also been in contact with the referring veterinarian over this time and has kept her informed of our progress in treating this mare for her diseased front feet.
One of his original questions for me before I met him or this mare, "Crystal", was as follows:
He writes in his email, "I'm hoping you can help me out. I've just purchased a broodmare with navicular. Would it be possible for you to provide me with some information before breeding this mare? I looked at the x-rays with the previous vet and she suggesting cutting the nerves on this mare and didn't understand why the previous owner hadn't done it sooner. What are the pro's and cons of this nerve cutting? Thank you for your time."
My response to him four months ago was as follows, and with his permission I am sharing this information with any and all of you who would like to explore with me what has traditionally been happening with these horses and why it is high time we reevaluate the way we think about and treat these very common hoof problems:
The procedure you are referring to is known as a "neurectomy". It is generally performed on horses that have had chronic pain problems in their feet, most notably "navicular" problems. The horse is put under general anesthesia and the digital nerves on both sides of the lame leg AND the more sound leg are isolated and cut--most often a section of the nerve on both sides is removed and the ends "capped" with the leftover nerve sheath. The reason that both legs are surgicated is because most horses end up quite lame in the leg opposite the originally lame one if it is left intact. Thus, one can easily appreciate that even though a horse only shows lameness in one of the forelegs, both are affected in a horse with "navicular" disease or "navicular" syndrome. The result of the surgery is that the horse loses sensation from this point downward and is unable to feel the pain from the diseased foot anymore. Usually the limping that was due to the pain in the area goes away and the horse can
continue to be used. The horse is thus returned to "soundness".
This procedure costs anywhere from $250 to $1500 depending on where it is done and who does it. It is "effective" for around one to two years--sometimes not that long, sometimes longer, but all of these horses eventually regrow some nerve connections and regain sensation of the area that was originally
desensitized. The lameness then returns and the procedure can be repeated at that time to keep the horse sound.
As you can easily see, this procedure addresses only one thing for the horse and the owner: the head bobbing lameness.
There are some very real and potentially devastating negative side effects of digital neurectomies in horses. Often times the raw ends of the nerves become irritated to the point of developing extremely painful nerve tumors called neuromas, leading to further surgeries to remove them. Other times, the digital arteries and veins that lie immediately parallel to the cut digital nerves become scarred and the resulting stagnation of circulation leads to foundering of the worst degree. Localized infections, scarring of tendinous and ligamentous structures and unsightly swellings are also common. Thus, a procedure designed to provide temporary relief from a widely misunderstood type of lameness often leads to further pain, loss of use and early death for these affected horses. Performing these surgeries is severely disruptive to the horse's lower leg anatomy, physiology and energy patterns, and commonly leads to irreparable damage.
"Navicular" problems, often referred to as "heel pain" or "caudal heel syndrome" start presenting symptoms in horses as young as two and three years old when their hooves are either allowed to overgrow in to a deformed shape and/or their feet shod at this young age. The still-developing coffin bones and sensitive inner hoof structures are surrounded, constricted and over-pressurized by the progressively-deforming hoof capsules, starving them of vital movement and circulation, yet forcing them to attempt to function and survive in a physiologically stagnant state. Older horses are also plagued by what is termed navicular disease and innumerable other hoof problems when their hooves also succomb to deformities in structure and stagnation of function. These lamenesses occur after longer periods of what is traditionally thought to be the "best hoof care possible". When this "best hoof care possible" consists of infrequent trimming and/or shoeing, it is no mystery, but rather a highly pre
dictable and physiologic certainty, that these horses will suffer from hoof deformities and possibly debilitating lamenesses. "Killing me softly" takes on new meanings when it comes to the effects of the steel horseshoe on our equine companions.