The step that shrinks before dementia takes hold
Doges Editorial · 2026-06-27 · 5 min read
NC State researchers tracked 88 senior dogs on a five-meter walkway, twice a year, and found something specific: when a dog's front-leg stride gets shorter, the brain may be the reason — not the joints.
The dog walks down a straight hallway. Five meters, no distractions. No treats at the end, no verbal encouragement from the person on the other end of the leash — just whatever pace he sets himself. He has done this walk before, in this lab, with these people, six months ago. Nobody watching would notice anything different about his stride. But the researchers filming from the side, measuring the distance each front paw covers before the other one lands, would.
A walkway and 88 aging dogs
Researchers at North Carolina State University enrolled 88 geriatric dogs in an ongoing study of canine brain aging — the Longitudinal Study of Canine Neuroaging. Every dog was enrolled when they had reached at least 75 percent of their expected lifespan, which for an average-sized dog works out to roughly 12 years. Twice a year, each animal came into the lab for a comprehensive assessment: physical, neurological, and orthopedic exams; hearing and vision testing; blood work; owner questionnaires about cognition and pain. The paper, led by postdoctoral researcher Shaghayegh Rafatpanah Baigi, was published June 24 in Frontiers in Veterinary Science (DOI: 10.3389/fvets.2026.1814017).
One of those questionnaires was the Canine Dementia Scale, or CADES. It tracks behavioral markers: getting disoriented in familiar spaces, sleeping at the wrong hours, failing to recognize people, standing at the wrong side of the door. It is the kind of scale built from things owners quietly accumulate and then dismiss as normal aging. Another tool — the Canine Brief Pain Inventory — captured chronic pain, since pain can also change the way a dog moves, and the researchers wanted to separate the two effects.
The walking section was deliberately stripped down. The dogs moved along a straight five-meter path at their own pace, on a slack leash, with no food reward at the finish line. Trained observers measured the distance each stride covered — separately for front legs and back legs — and adjusted the numbers for each dog's height to make them comparable across breeds.
What the data showed
The front legs told a different story from the back legs. As cognitive decline scores went up, front-limb stride length went down. The relationship held even after the researchers controlled for age and pain. More precisely: a 10-point increase on the Canine Dementia Scale corresponded to approximately a 1.2 percent reduction in front-limb stride length. The back legs showed no equivalent pattern.
We know that in humans, changes in stride length have been linked to cognitive impairment and dementia. That relationship hasn't been investigated in dogs, so we created this study to examine the problem.
— Dr. Natasha Olby, professor of neurology, NC State College of Veterinary Medicine
What made the finding more striking was where the effect came from. In the full statistical model, cognitive decline was a better predictor of front-limb stride change than age was by itself. The step shortens because of what is happening in the brain — not simply because the dog is getting older.
Why the front legs, not the back
The split between front and back limb patterns has a neurological explanation. A dog's hind legs function primarily as a propulsion system — they push forward. The front legs do something more cognitively demanding: they handle braking, change direction, and integrate spatial awareness of the environment ahead. That kind of sensorimotor coordination runs through the brain's cortex — precisely the area most affected by cognitive dysfunction.
It is fascinating to see that cognitive decline affects front legs and hind legs differently. In dogs, the hind legs are important for moving forward, while the front legs also change direction and initiate braking.
— Dr. Natasha Olby, NC State College of Veterinary Medicine
The cerebellum and cortex work together to plan every step. As the cortex deteriorates, the brain's ability to anticipate and adjust spatial movement weakens. The hind legs, running more on spinal reflex than cortical planning, stay relatively unaffected. The front legs, which require more real-time environmental integration, shorten first.
The quiet epidemic in older dogs
Canine cognitive dysfunction syndrome affects 28 percent of dogs aged 11 to 12, and 68 percent of dogs aged 15 to 16 — figures from a survey of 180 randomly chosen older dogs by Neilson and colleagues, published in the Journal of the American Veterinary Medical Association. The syndrome progresses slowly, its early signs easy to fold into ordinary aging, and there is no single definitive diagnostic test. A blood draw cannot confirm it; a scan cannot rule it out.
What amplifies the problem is a persistent diagnosis gap. A 2010 cross-sectional survey by Salvin and colleagues, published in the Veterinary Journal, found that only 1.9 percent of affected dogs had ever received a formal CDS diagnosis — not because the condition is rare, but because owners accept its signs as the ordinary cost of getting old. The early markers are small and easy to dismiss: a dog who stands at the hinge side of the door, wakes at 2 a.m. not knowing where she is, forgets a cue she has known since puppyhood. Those changes accumulate for months before they become unmistakable. A stride measurement that is subtly shorter might appear before any of those behavioral signs register.
An observation that costs nothing
The practical appeal of this finding is that it requires nothing more than attention. No wearable sensor. No specialized equipment. A vet can assess stride length from a smartphone video. An owner who takes the same dog on the same route every morning for years is, in effect, already gathering the data — they just may not have known what they were looking at.
If owners notice that their dog's front leg stride is becoming shorter they should visit their vet, for there are possible alternative causes such as arthritic pain or neck issues that can be treated.
— Dr. Natasha Olby, NC State College of Veterinary Medicine
That qualification matters. Pain — from arthritis, from a cervical disc, from something else entirely — can also shorten the front stride, and those conditions have effective treatments. A shorter step is not a diagnosis of dementia. It is a reason to make an appointment. Once a cognitive decline diagnosis is made, earlier intervention allows for more options: environmental enrichment, dietary changes, medications that can slow the progression.
What it means for the walk around the block
Next time you walk an older dog — watching those familiar ears bob ahead, the same corner turns, the same pause at the lamppost — it is worth noticing the stride. How far does each front paw reach forward? Is the distance roughly what it always was, or do the steps seem to come closer together than they used to?
You do not need a ruler. The walk you take every morning is already one of the closest observations you make of your dog's body. The research from NC State is a reminder that the information is there — in the way they move, in the distance between each step — if you are paying attention to it.
Every walk is a record. You just need to know what you are reading.