Why Is Pain Even a Debate When Behaviour Is the Symptom?

One of the most common things dog professionals hear is this:

“But there are no signs of pain.”

This sentence often comes just before a dog is labelled stubborn, dominant, anxious, badly trained, or aggressive.

Here is the uncomfortable truth. If a dog’s behaviour has changed, escalated, or become difficult, that behaviour is a sign. Behaviour is how dogs communicate discomfort, stress, fear, and pain. Dogs do not tell us with words. They tell us with actions.

So the real question is not “Is there pain?” The real question is “Why are we still surprised when behaviour is the sign of pain?”

Dogs Do Not Show Pain Like Humans

Humans are vocal and explicit when something hurts. We limp dramatically, complain, rest, or seek medication.

Dogs are different for one simple reason.They evolved to survive.

Research shows that dogs often compensate extremely well for discomfort. They shift weight, change posture, avoid certain movements, or alter how they interact with their environment long before they show an obvious limp or cry.

By the time pain is “obvious,” it is usually advanced.

Behaviour Is Not Separate From the Body

One of the biggest myths in dog training and behaviour is that behaviour and physical health are separate issues.

They are not.

The brain and body are part of the same system. Pain changes how the nervous system functions. It lowers tolerance. It increases irritability. It reduces the ability to cope with stress.

Studies consistently show that pain is linked to:

  • Aggression and snapping

  • Reactivity to dogs or people

  • Avoidance of handling

  • Resistance to training

  • Anxiety and hypervigilance

  • Night-time restlessness

  • Changes in social behaviour

In fact, multiple peer-reviewed studies have found that dogs displaying aggressive behaviour often have undiagnosed pain. In some cases, treating the pain significantly reduced or resolved the behaviour.

This is not because the dog became “nicer.” It is because the dog became more comfortable.

“But My Dog Still Plays and Runs”

This is another common misconception. Dogs can be in pain and still run, play, jump, and greet people enthusiastically. Adrenaline temporarily masks pain. Excitement overrides discomfort. Survival instincts take over.

Think of a human who injures their back but still pushes through work or sport. The pain shows up later. Stiffness increases. Irritability grows. Sleep is disturbed.

Dogs are no different.

In fact, many dogs with chronic pain show what professionals call “pain masking behaviours.” These include:

  • Sudden bursts of activity followed by stiffness

  • Pulling on the lead to redistribute weight

  • Reluctance to sit, lie down, or get up

  • Sitting off to one side

  • Avoiding touch on specific body areas

  • Lip licking or yawning when handled

  • Increased reactivity in the evening

  • Growling seemingly “out of nowhere”

None of these look like traditional pain signs. All of them are.

The Myth of “No Clinical Findings”

Another harmful belief is that if scans or exams show only “mild” findings, pain cannot be significant.

“Mild” on an X-ray does not mean mild to the dog.

Research in both human and veterinary medicine shows that pain severity does not always correlate with imaging severity. Some individuals with minimal visible changes experience significant pain, while others with severe changes cope better.

Pain is influenced by:

  • Nervous system sensitivity

  • Previous injuries

  • Chronic stress

  • Fear and anxiety

  • Learning history

This is why behaviour professionals often raise pain concerns even when findings appear subtle. Behaviour reflects how the dog experiences their body, not how the image looks on a screen.

Why Training Alone Is Not Enough

Training does not remove pain.

You can teach alternative behaviours. You can manage triggers. You can improve predictability. But if the underlying discomfort remains, progress will often plateau or regress.

This is why some dogs respond beautifully in controlled sessions but struggle at home, in the evening, or after activity.

So Why Is This Still a Debate?

Because pain is inconvenient. It requires veterinary input. It challenges simple explanations.

If a dog’s behaviour has changed, escalated, or become unsafe, pain must be considered.

Not as an afterthought.
Not after training fails.
Not only if there is a limp.

Behaviour is not separate from pain.
Behaviour is often the symptom.


Suzi Walsh