How Do Vets Diagnose Arthritis in Dogs? A Step-by-Step Look at the Exam

By Elizabeth Fernandez, DVM, CVAM, CVTP, CVCH, CVFT, CTCVHP, CTPEP

✓ Medically reviewed by Elizabeth Fernandez, DVM, CVAM, CVTP, CVCH, CVFT, CTCVHP, CTPEP — August 6, 2026 For general education — not a substitute for veterinary care.

Joint & Mobility · August 9, 2026 · 5 min read

Vets diagnose arthritis in dogs through a hands-on orthopedic exam, a gait assessment, and X-rays that confirm joint changes.

The dog I remember most clearly was a nine-year-old Labrador named Diesel, sixty-eight pounds, who came in because his owner said he’d started “thinking about it” before jumping into the truck bed. Not refusing — just pausing, shifting his weight, then committing. She’d noticed it over maybe six weeks, worse on cold mornings, better by midday once he’d been up and moving. That pause is one of the more reliable things I look for, because dogs are stoic about pain and rarely limp in a way that reads as dramatic. Diesel wasn’t lame in the classic sense. He was just quieter in his hips than he used to be, and it took a structured exam — not a glance across the room — to confirm what was going on.

The verdict up front: there’s no single test that diagnoses arthritis in dogs. It’s a layered process — history, observation, hands-on palpation, and imaging — and each layer rules things in or out. Skip a layer and you risk treating the wrong problem.

Start with the history, not the joint

Before I touch a dog, I want the owner’s timeline. When did the change start? Is it worse after rest or after activity? Does the dog still jump on the couch, take stairs normally, or squat fully to eliminate? Owners often undersell these details unless asked directly, and the answers point me toward orthopedic versus neurologic versus systemic causes before I’ve even watched the dog walk.

I also ask about weight history and any recent changes in exercise, surface, or routine — a dog that moved from carpet to hardwood, or gained six pounds over a winter, can look “suddenly stiff” for reasons that aren’t purely joint-driven.

Watch the dog move before you touch it

Gait assessment happens next, and it happens on a leash, on a non-slip surface, at a walk and then a trot if the dog tolerates it. I’m watching for head bob (usually front-limb lameness), hip hike or a shortened stride (often hind-limb), and asymmetry between left and right. A dog with bilateral hip or stifle arthritis can look deceptively even at a walk — the asymmetry only shows up at a trot or after a sit-to-stand.

I’ll also watch the dog rise from a sit. Slow, stiff, or asymmetric rising is one of the more consistent early signs of osteoarthritis, and it’s something owners can track at home between visits.

Palpate every joint, not just the obvious one

This is the part that actually confirms or reshapes the diagnosis. I go joint by joint — hips, stifles, hocks, elbows, shoulders, spine — checking range of motion, crepitus (that gritty or grinding feel), effusion (fluid swelling), and pain response on flexion or extension. A dog favoring a hip can have a torn cruciate ligament in the opposite stifle instead, and you won’t catch that without checking both ends of the dog.

For a dog like Diesel, the exam found reduced hip extension bilaterally with mild crepitus and no effusion — consistent with chronic hip changes rather than an acute injury. That combination of findings is what pushed us toward imaging rather than assuming and treating blind.

Confirm it on imaging

Radiographs are the standard way to confirm arthritis and rule out other structural causes — bone tumors, fractures, severe dysplasia, or discospondylitis. Sedated X-rays give cleaner, more diagnostic views than an awake dog can hold still for, and they let us grade the severity of joint changes, which matters for setting expectations with the owner. In some cases — especially when the exam and X-rays disagree, or when a soft-tissue injury like a partial cruciate tear is suspected — I’ll recommend advanced imaging or referral to a surgeon.

Bloodwork isn’t diagnostic for arthritis itself, but I’ll often run it anyway in an older dog to rule out concurrent issues, and to make sure any medication we start is safe for that individual’s kidneys and liver.

Where this becomes a whole-patient conversation

I’ve watched this play out with owners more times than I can count: the X-rays come back showing real change, and the question shifts from “does my dog have arthritis” to “what do we do now.” That’s usually the harder conversation, because arthritis is a chronic, progressive condition, and there’s no single fix that reverses it. What I can offer is a plan — weight management, appropriate exercise, medication when pain is significant, and often a joint-support supplement layered underneath the rest.

On the supplement side, I try to be specific rather than vague about what’s actually been studied. Chondroitin has research behind it for supporting healthy synovial fluid homeostasis, according to a study published in Frontiers in Veterinary Science. Glucosamine HCl has been reviewed for its ability to help prevent experimentally induced cartilage degradation in vitro, per a review in the Journal of Veterinary Medical Science. Green-lipped mussel powder has also been studied in inflammatory joint models — one paper in Nutrients found that mussel-derived compounds alleviated paw swelling and reduced inflammatory markers in a rat model. None of that replaces a diagnosis or a vet-directed treatment plan, but it’s useful context when an owner asks what’s actually behind the ingredients on a supplement label — the kind of question I get every time I hand someone our Best Joint Supplement for Dogs breakdown.

For dogs already diagnosed and managing chronic changes day to day, I usually point owners toward practical, low-effort adjustments first — non-slip flooring, ramps instead of jumps, and a consistent low-impact exercise routine — which is exactly the territory covered in How to Help an Old Dog With Stiff Joints.

What arthritis is not

Not every stiff dog has arthritis, and that distinction matters. Panosteitis in young large-breed dogs, lumbosacral disease, cruciate tears, and even simple soft-tissue strain can all mimic early arthritis symptoms. This is part of why I don’t diagnose off a single visual impression — a dog that’s “just getting old” sometimes has something more acutely treatable going on, and a full workup is the only way to know which one you’re dealing with.

Diesel’s owner asked me, near the end of that first visit, whether we’d caught it early enough to slow things down. I told her what I tell most owners in that chair: we can’t undo the joint changes already on the film, but we can absolutely change the trajectory from here — weight, movement, and the right supportive layers, chosen deliberately rather than grabbed off a shelf. She went home with a plan, not a verdict of decline, and that’s usually the more honest thing to offer. If your dog is a similar age and has started weighing that jump into the truck, what would a full week of watching their rise-from-sit actually tell you?