How Do Dogs Feel Pain? Vet Approved Facts
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Perhaps you’re playing fetch with your dog outside. Suddenly, your pup yelps and is evidently in pain. What your pet is experiencing is not too different from what you may feel if you burn yourself or stub your toe. The difference is that you can tell someone what’s wrong and how it hurts. Your dog can only react to the fact that something is wrong even without understanding what’s happening.
Defining Pain
Pain has an evolutionary basis because of its role in survival. It warns us of a potential threat that can harm us. The International Association for the Study of Pain (IASP) defines it as “An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.”¹
Even though early humans diverged about 92 million years ago from canines, it doesn’t mean we don’t share common sensory responses, such as pain. It serves the same purpose for people as it does for our dogs. The experiences that the IASP references originate in the central nervous system (CNS), which includes the brain, spine, and spinal nerves.²
Pain occurs through the action of specialized nerve cells called nociceptors. They perceive the potentially harmful stimulus and send that information to the spine. That can trigger an instinctive reaction, such as your dog continually lifting their feet off the ground if it’s too cold outside. The information goes to the brain through pathways that vary with the organism.
People believe that since our pets respond similarly to pain, they must feel it too. While we may think that only vertebrates like humans (and dogs) can experience pain, some evidence suggests that even insects and other invertebrates may also feel pain. Even if other organisms can’t communicate their experiences as we can, there’s no denying it has evolutionary and survival value for any living thing.³
Therefore, we can conclude that pain is an early warning sign that something is wrong. It’s not always diagnostic of itself because many things can cause it. However, it’s a useful way for you and your veterinarian to figure out what’s going on with your dog if they act like they’re in pain.
Types of Pain
Several types of pain exist. Veterinarians typically speak of it as being either acute or chronic. The former is an immediate stimulus that is often short-lived. Your dog may step on a sharp rock on the trail while you’re out for a walk and yelp in response. Your pet backs away from the offending stone, and the pain diminishes.
Chronic pain doesn’t have the same physiological value. It doesn’t go away and lingers, sometimes worsening over time. It can involve long-term health conditions, such as osteoarthritis or cancer. Neuropathic pain comes from damage to the nervous system following trauma or nerve damage from different causes. People often feel it as a tingling or numbing sensation.
Humans can also experience psychological or psychogenic pain that may have non-physical reasons. Whether animals perceive it in the same way is unknown. That brings us to the challenges of assessing and managing your dog’s pain.
Assessing Pain
Dog owners know their pets well. They can tell if something is up by behavioral changes. You may notice that your pup isn’t eating like they usually do. They may seem lethargic. In the case of pain, you might detect your dog limping or being reluctant to jump into the car. Your pet may yowl if you try to clean their ears. Most veterinarians now realize how vital pain assessment is to treatment.
Many animals will hide pain, complicating matters. Cats are notorious for it, often hiding instead of showing signs of weakness. It makes evolutionary sense not to show that you’re vulnerable, but that makes it hard for us to recognize that our pets are suffering. After all, many have a high threshold for it. Your pup may still wag its tail even though their sore paw is throbbing.
It’s difficult for your vet to determine what’s wrong with your dog without the benefit of knowing how your pup usually acts. Being in a new place can trigger behaviors that have nothing to do with pain, such as barking or growling. Researchers figured out quickly that pain evaluation must start with the one who knows the dog the best— their owner.
You’re probably familiar with the Numeric Rating Scale (NRS-11). It’s a way that a human can convey their pain intensity, using a zero to 10 scale, based on its effects on their ability to do everyday tasks. Since your pet can’t communicate this information, it’s up to the owner to assess the situation. Several reporting methods exist. We’ll delve into two of the most used options.
Helsinki Chronic Pain Index
The Helsinki Chronic Pain Index is a questionnaire that owners will complete by giving a numeric score on a 0 to 4 scale for 11 parameters. It provides a simple yet valuable means for an owner to evaluate their dog and convey it in an understandable way to their veterinarian. Scientists originally developed this test for pets with osteoarthritis. However, it has shown promise for determining a dog’s general well-being.
It’s worth noting that it’s not sufficient just to identify pain. It’s also vital to judge its intensity. That’s the value of tests such like this one. Dogs are like people in that they may avoid some everyday activities simply because it hurts too much. It’s an excellent way to figure out a pet’s quality of life.
Canine Brief Pain Index
The Canine Brief Pain Inventory is a similar assessment using a 0 to 10 scale. This tool evaluates a dog’s pain level and the degree to which that pain interferes with function. Its value lies in providing information about whether an animal is getting worse or recovering. It’s often used with dogs with osteoarthritis or bone cancer.
This test differs because it asks the owner to assess a pet’s quality of life too, going from poor to excellent. It can help an individual make an honest judgment if euthanasia is on the table. Sometimes, ending our pet’s pain means accepting our own.
Conclusion
No one wants to see an animal in pain, let alone our beloved pets. Recognizing pain and accurately assessing it is a vital part of ensuring a good quality of life for our canine companions. Research has provided priceless tools to make it possible to get our pups on the road to wellness that much quicker. It’s the best thing we can do as pet owners.
Featured Image Credit: Ruben PH, Shutterstock
