pain | Horse Racing Free Tips

Pain Management Strategies for Laminitic Horses: Different Solutions For Different Causes

Very few equine conditions can be as debilitating as laminitis, which can be triggered by a variety of events or occur on its own. Laminitis occurs when the laminae, a set of finger-like structures which support the coffin bone and hold it in place in the hoof capsule, become inflamed. This inflammation is incredibly painful and can be catastrophic for the horse's athletic career.

Many horses that develop laminitis are not euthanized because of the changes to the laminae, but because of the uncontrollable pain the condition brings on. A virtual session of the 2020 American Association of Equine Practitioners annual convention summarized the current research on the best way to manage pain in different types of laminitis cases.

The pain a laminitic horse feels is multidimensional. It can be brought on by pressure within the hoof capsule, inflammation of the laminae, tearing of soft tissues, a reduction of blood supply to the hoof, contact between the coffin bone and the sole of the hoof, and neuropathic pain.

Dr. Katherine Ellis of Gail Holmes Equine Orthopaedic Research Center at Colorado State University, explained several different strategies for different causes of laminitis. Phenylbutazone (bute) is commonly given to treat laminitis, but that other drugs, including as flunixin, ketoprofen or firocoxib, may be better at controlling laminitic pain.

Ellis stressed that if an NSAID doesn't seem to be providing pain relief to a laminitic horse, another should be considered. A horse that has developed laminitis from overindulging in grain would benefit from having his hooves submerged ice water. This will be helpful for controlling pain and limiting injury. Ideally, the hooves would be submerged constantly for 48 to 72 hours, though this is a labor-intense endeavor.

Metabolic issues like equine metabolic syndrome (EMS) and Cushing's disease can put a horse at risk for chronic laminitis. Gabapentin has been shown to be an effective pain medication for horses with chronic laminitis, but higher doses of pain medications may be necessary to provide relief.

Ellis noted that acupuncture and use of a TENS unit may offer some additional pain relief. Chiropractic work and massage may offer respite from body pain brought on by the laminitic stance.

A horse that has an injury to a leg may develop supporting limb laminitis. Ellis suggests using morphine and butorphanol blocks and fentanyl patches to help control pain in these cases. A tramadol and ketamine infusion can also be used. Ellis notes that biologics like stem cells and platelet-rich plasma can be used for the anti-inflammatory properties.

Hoof Abscesses: A Sign Of Something More Sinister?

A horse with an abscess in his hoof can be startling to see he: He may be so painful he's loath to bear any weight on the affected limb, making horse owners fear a broken leg. One abscess can be time consuming and frustrating to heal, but a horse that develops multiple abscesses in different feet may have more going on than simply poor hoof condition.

Hoof abscesses are fluid-filled cavities under the sole or the hoof wall. They can be caused by sole bruising, puncture wounds or hoof cracks. Though some abscesses are only uncovered by the farrier during routine trimming—never causing the horse any discomfort—others are extremely painful. Abscesses can drain on their own, either down through the bottom of the hoof or up through the coronary band, or a drainage channel may have to be cut to offer the horse relief.

There are many concoctions for hoof abscesses, from veterinary-prescribed products to home remedies. Most products focus on drawing the material out of the abscess. Antibiotics are often not needed, but pain medication is essential to provide relief to the horse and prevent harm to the other hooves from bearing excess weight.

If an abscess doesn't begin to heal in a few weeks, a foreign body may be trapped inside the hoof, like a splinter or nail—or even a bone chip. A horse that is experiencing abscesses that don't heal well in multiple feet most likely has something else wrong and the abscesses are secondary.

Metabolic issues may cause a horse to have multiple of abscesses that don't heal well. Cushing's disease and equine metabolic syndrome (EMS) can cause laminitis, which can predispose a horse to abscesses. A veterinarian can run bloodwork to determine if a horse has either of these conditions and if they are the cause of the abscesses. Once the underlying conditions are controlled and hoof damage is addressed, the abscesses should decrease in both frequency and severity.

Horses That Struggle With Attention May Be Battling Pain

Horses that ignore their surroundings (including their handlers) may not be cranky or depressed—they may be in pain. Drs. Louise Dodds, Laura Knight, Kate Allen and Joanna Murrell created a study that tested the reactions of 20 horses to novel objects and sounds just before and after they underwent a surgical procedure. They compared the surgical horse's reactions to those of 16 control horses who didn't have surgery.

The research team found that the surgical horses spent significantly less time interacting with a pool noodle and a flipper immediately after surgery than they did before the surgery. There was no difference in interaction times in the control horses when they encountered the objects a second time.

Surgical horses also were less likely to react to the noise of a hair dryer after surgery than before. The response of the control horses did not change from one exposure to the next.

The scientists conclude that pain effect a horse's response and startle times. Exposing the horse to a situation that demands attention may be a useful biomarker of pain, they say.

Bute: More Isn’t Better, It Can Be Dangerous

Phenylbutazone (“bute”) should have a place in every horse owner's first-aid arsenal to fight pain. However, if a traditional dose is given and the horse finds no relief, research says owners should reach for a different medication, not just administer additional doses of bute.

To test this theory, Dr. Ronald Erkert of Oklahoma State University conducted a recent study using three different pain treatment protocols on nine horses that were chronically lame in a front leg; each protocol lasted for four days. One group had injectable bute administered at two grams per 1,000 pounds. The second group had four grams per 1,000 pounds of bute injected. The third group received a saline injection to serve as a control. Before each injection and at six, 12 and 24 hours after the final dose, the horses were given a lameness exam and trotted on a force plate.

Erkert found no difference in lameness scores whether the horse was given two grams of bute or four grams of bute per 1,000 pounds. Erkert said that though his study was on injectable bute, administering additional grams of oral bute also has no significant benefit. Four grams of bute per 1,000 pounds approaches near-toxic levels. Bute toxicity can show up as diarrhea, gastric ulcers, colic, kidney failure and endotoxic shock.

Erkert recommends owners who give a horse bute and see no significant change in the horse's comfort level consult with their veterinarian to find a different pain control drug rather than administering more bute.