column By: Walt Cottrell, DVM | June, 17
Dear Dr. Walt:
Last fall my 5-year-old male Lab cut his main pad, we still don’t know on what, and was laid up for a good part of the season because it was slow to heal. I’ve had him on rough surfaces to avoid last year’s experience. Is there anything else I can do?
The answer has to be “No” and “Yes,” and I am happy to say, mostly “Yes.” Before we delve into the choices, let’s first see what we are dealing with. The skin of the pad is the toughest region of the dog’s skin. It has adaptations that contribute to its strength and ability to resist injury. The most obvious is the densely packed array conical papillae, the tips of which we can readily see when we look directly at the pad. These make for a rough but flexible surface that improves traction. Beneath these is the digital cushion that is comprised mostly of fat but which has layers containing both fibrous and elastic tissue. The pad also has an abundant supply of blood vessels. So it is structurally strong and equipped to withstand, and repair, injury. The papillae, the thickest of those layers, and the tissue (dermis) just below it are the parts usually damaged by lacerations or penetrating injuries. Pads are strong and highly adapted but also vulnerable.
When injuries do occur, the challenge in repairing them is to overcome some of these adaptations long enough for healing to take place. The bleeding has to be stopped, and foreign material, if present, has to be removed and the wound made clean as possible. Then the tissues have to be realigned and stabilized so the standard inflammatory response can heal the damage. Once the first three are accomplished, some combination of surgical glue, sutures or staples and then bandaging are usually employed. But now the patient is awake and upright and, whether or not it chews or licks the bandage and sutures, is still putting stress on the repair by simply getting around. No matter how clever the suture pattern or imposing the bandage, it takes diligent aftercare to get primary healing. In an active sporting dog, it is more commonly a longer stepwise process like you experienced.
Short of identifying obstacles like old trash dumps or roadside glass to avoid, there are only a few possible interventions, and they may or may not improve on what evolution has so far achieved. Akin to prevention of sore feet, one method is boots, and these work for some dogs and some owners in some terrains but not necessarily all. Seeing how quickly even the densest Cordura is damaged gives us an appreciation of what these pads can stand. Another method is the application of one or more of the various liniments designed to elicit a low-grade inflammatory response and, theoretically, the pad is toughened as a result. None of the ones I have tried have ever made an appreciable difference. Then, as you are doing, subjecting the pads to rough surfaces will intuitively also strengthen the pad. But alas, we also know that those important papillae can be scrubbed down in the process, as they are when dogs are kept 100 percent on concrete.
Even though the specter of such an injury has our attention, concentrating entirely on the pads might be shortsighted. The pad is surely where the skin meets terra firma, and it has to be healthy, but it is part of a system, everything from the eyes and nose to the pad itself. Visual and olfactory clues ideally tell the dog where many dangers lie. The dog’s wind and agility give it the responsiveness to avoid obstacles. The nails enhance traction and aid in rapid course corrections. The neck and limbs are an elegantly arranged system of muscles, uniquely shaped bones, and ligaments and tendons acting as levers and pulleys that combine for strength, speed and maneuverability. What I’m getting at is that the best part of what you are doing is conditioning, building that muscle memory and capacity for your dog to negotiate the places its instinct and training will take it. Indeed, if it is the right weight, strong of limb and wind and experienced, it will stand the best chance of avoiding injuries of all types, including those to pads. As dogs age, they might lose some of this innate and acquired fitness, and your veterinarian can help you navigate these changes. But without doubt the better a dog is conditioned, from head to toe, the better it will be able to deflect serious injury through those early and middle years and the better the outcome as time goes on.