Location a Key Factor in Assessing Wounds

By Brenden Van Wyk

Horses can suffer from all types of wounds, and while some wounds look much worse than others, the primary assessment of their severity is the same as that of gauging housing prices: location, location, location.

This claim is backed by Dr. Suzanne Mund, a veterinarian and graduate student in the Western College of Veterinary Medicine’s Department of Large Animal Clinical Sciences. Her research focus is on wound healing through the use of stem cells.

“It doesn’t matter necessarily how big the wound is, what matters more is where it is,” stresses Mund. “Size doesn’t matter when it comes to wounds, at least not as much. A larger wound in a safer place isn’t as bad as a tiny, little puncture wound over top of the joint.”

Small puncture wound over medial hock: This wound demonstrates that small puncture wounds can be a lot more damaging than they appear on the surface. This tiny puncture wound communicated with the tarsometatarsal joint, causing a joint infection that required intensive treatment. Photo: Dr. Suzanne Mund

Because of the increased risk of bleeding and infection, more severe wounds often occur in locations with more blood vessels - between the hind legs, up in the arm pits, along the jugular vein, and underneath the skin. Wounds on the backs of legs are also serious because of the potential damage to vital ligaments and tendons.

Wounds in high-motion areas — mainly joints — increase the risk for major complications. One serious condition is when gas or air becomes trapped underneath the horse’s skin (subcutaneous emphysema).

“As the horse walks, the wound [continually] gapes open and closed and air that is pushed up underneath the skin can spread throughout the body,” explains Mund. If the air dissects along the front of the horse’s chest and into the potential space between the lungs and the heart, it can cause a collapsed lung that requires emergency care.

Mund emphasizes that any wounds found in highly vascular regions or around joints should be immediately checked by a veterinarian. Lacerations - tears or cuts on the skin - are comparatively less serious and can usually be treated by simply flushing, draining, and suturing them. Mund recommends calling the veterinarian early, particularly to avoid the growth of too much granulation tissue (proud flesh) on the limbs and/or around joints.

Puncture wounds are potentially more dangerous than open lacerations because they can carry debris and bacteria deep down into the bottom of the wound, says Mund. “The outside can heal before the inside has healed, which can set up an environment for abscess formation or increase the risk for developing gas gangrene or tetanus.”

Above: Upper lip laceration before and after: Lacerations of soft tissue in non-vital areas such as the lip can be disconcerting but are amenable to suturing and often heal well with minimal scarring. This horse healed exceptionally well with hardly a scar. Photos: Dr. Suzanne Mund

Below: Small laceration over pastern: Lacerations on the limbs are always concerning regardless of how large or small because of the proximity of many vital structures such as tendons, ligaments, tendon sheaths, bone and joints. In this case, the small laceration was cause for concern because of its proximity to the pastern joint and the tendon sheath. Photo: Dr. Suzanne Mund

Given their small size, puncture wounds can be easily missed and swelling can often obscure the original wound. Complications don’t always arise from puncture wounds, but they usually require intensive veterinary management regardless of their severity.

If a horse suddenly becomes lame, Mund suggests checking for leg wounds or a possible foot abscess, and recommends that owners contact their local veterinarian to pinpoint the cause.

“Nine times out of ten, [lameness is caused by] a foot abscess, which is easy to manage,” says Mund. “It’s the other one out of ten times that it’s something more serious such as septic joints, broken bones, or an injury involving torn ligaments.”

Wounds usually cause bleeding. Improper treatment of a bleeding wound may do more harm than good, especially if a horse owner tries to remove an object that’s causing the bleeding.

“If you see a nail or another type of foreign body, it’s very important not to remove that until you call the veterinarian,” says Mund. “It’s better to have the vet examine the wound (often through x-ray) and determine the appropriate treatment.”

For sudden lameness, check for wounds in the leg or an abscess in the hoof, and consult your veterinarian to determine the exact location and recommend treatment. ©Thinkstockphotos/Monkey Business

Horse owners should immediately call their veterinarian if a wound exposes internal structures.

“Any exposed [bones], ligaments, or tendons need to get healed as soon as possible, as these are vital structures that can impact the future use of your horse,” says Mund.

While owners can’t completely protect their horses from everything, properly maintaining fences can help to avoid accidents.

“It’s important to go walk the perimeter of your fence at least twice a year and look for loose wire and loose nails sticking out,” recommends Mund. “It doesn’t really matter what type of fencing material you decide to use; what’s more important is how you maintain it. Loose, smooth wire can be just as bad as barbed wire [if improperly maintained].”

And while veterinarians are the trained experts in wound management, owners can proactively improve their horse’s outcome by preparing the horse before the vet arrives.

Shearing injury over fetlock: This wound was the result of a trailer accident causing a devastating shearing injury of the fetlock joint. The sagittal ridge of the distal canon bone, the extensor tendon, and the fetlock joint were all disrupted, necessitating euthanasia due to a grave prognosis. Photos: Dr. Suzanne Mund

For example, lead the horse (if it can still walk) to a quiet area, perhaps with a calming, equine companion, and follow the veterinarian’s advice on stemming any bleeds.

However, Mund emphasizes not to clean any wound unless explicitly instructed.

Overall, if any horse owner spots a wound and is unsure of what to do, Mund recommends contacting a vet – even if it’s just for a consultation on the phone.

“Advice is free,” says Mund. “Addressing a small problem now will prevent larger problems in the future.”

Brenden Van Wyk completed his Master of Science (MSc) degree program at the Vaccine and Infectious Disease Organization (VIDO) in February 2016.
      
This article was previously published in the July 2015 edition of Canadian Horse Journal.

Properly maintained fences help to prevent injuries. Walk the fence line at least twice each year, looking for hazards such as loose wires and nails, broken boards, and trees or branches that have fallen on the fence. Photo: ©Canstockphoto/Tristesse