Search this question and you will be told, on page after page, that long nails alter your dog's posture, shift weight backward and accelerate arthritis. In 2026 a team in Stuttgart measured it on an instrumented treadmill, before and after trimming. The gait did not change.
Trim your dog's nails — but for the reasons that survive scrutiny. Nails that curl into the pad, snag and tear, or catch on carpet are real, documented problems. The claim that nail length itself degrades gait and loads the joints is the one most often used to sell clippers, and it is the one a controlled study failed to reproduce. We sell clippers. We are telling you this anyway.
What the evidence supports
| Well supported | Nails curling into the pad; snagging and tearing; loss of traction on hard floors |
|---|---|
| Not reproduced in testing | That nail length alters gait parameters or ground reaction forces |
| Standard to trim to | Nails should not contact the floor when the dog stands square |
| Frequency | Roughly every 3–6 weeks, depending on surface and activity |
| Already overgrown | Small trims every 1–2 weeks so the quick recedes — not one big cut |
| Prevalence | Among the most frequently recorded problems in UK primary care: 5.5–7.1% of dogs |
The study that tested the claim
Researchers at a veterinary physiotherapy center in Stuttgart recruited privately owned dogs across a range of breeds, sizes and conformations. Each dog walked on an instrumented treadmill while temporospatial gait parameters and ground reaction forces were recorded. Nails were then trimmed, and the same measurements repeated in the same controlled conditions.
If long nails were pushing weight backward off the front paws — the mechanism described on nearly every grooming page — this design would detect it.
It did not. The authors concluded that in clinically sound dogs, longer claws do not impair overall locomotor function. Paw pressure distribution did not change significantly either.
Long claws may not be the cause of altered gait, but rather a consequence of decreased natural abrasion due to abnormal or inefficient gait.
Trimming of nails in healthy dogs does not change gait parameters when comparing pre- and post-nail trim. Frontiers in Veterinary Science, 2026. DOI: 10.3389/fvets.2026.1728382
The reversal, and why it is clinically useful
That conclusion inverts the usual causal story, and it is the most practically valuable sentence in the paper. A dog whose gait is already abnormal makes less contact between claw and ground, wears the nails down less, and therefore grows longer nails.
On that reading, unusually fast nail growth is a signal worth investigating rather than a problem to cut away. The authors note documented routes to this: corn-like lesions on the digital pads causing a compensatory weight shift onto the metacarpal pad, and injuries to the digital flexor tendons reducing claw wear.
Practical version: if your dog's nails suddenly need trimming far more often than they used to, mention it to your vet. You may be looking at a symptom.
So why trim at all?
Because the remaining reasons are not disputed by anyone:
- Nails curl into the pad. Dewclaws are the usual culprits — they contact nothing, wear down not at all, and can grow round into the flesh. Painful, frequently infected, and a vet visit.
- They snag and tear. A torn nail is acutely painful and often needs treatment.
- They catch on carpet and furniture, and on slick floors long nails reduce pad contact and therefore grip.
- It is common. UK primary-care veterinary records rank overgrown nails among the most frequently recorded problems, at roughly 5.5–7.1% of dogs depending on the dataset.
None of these requires the gait claim. Trimming is ordinary maintenance. It is simply not the postural intervention it is marketed as.
Technique: the quick is the whole problem
The quick carries blood vessels and nerves. On pale nails it is the visible pink core. On dark nails it is invisible, which is why most owners stop trimming dark-nailed dogs altogether.
The dark-nail method: take thin slivers and watch the cut face. As you approach the quick a chalky white circle appears in the center of the cut surface. That is the stop signal — one more slice reaches blood.
Before you start, not after: styptic powder within arm's reach. Quicks bleed disproportionately and it startles both of you; having the fix already open is the difference between an incident and a disaster.
Pace: one nail per day is a perfectly respectable rate with a nervous dog. Ending a session while it is still going well is what builds tolerance. Pushing through a struggle is what destroys it, sometimes permanently.
Stop entirely if: your dog has ever snapped during a trim. Book a groomer or your vet. That is a sound decision, not a failure.
The overgrown-nail problem needs patience, not a bigger cut
When nails have been long for months, the quick has grown out with them. You cannot cut back to a correct length in one session without cutting through it. Small trims every one to two weeks encourage the quick to recede gradually. Budget a couple of months, not an afternoon.
Common questions
How do I know they are too long?
Stand your dog square on a hard floor. The nails should not touch the ground. Audible clicking while walking means they have been long for some time already.
Do walks wear them down enough?
On concrete and asphalt, sometimes. Dogs walked mostly on grass, and older dogs walking less, will need trimming regardless of mileage.
Do dewclaws need doing?
Especially. They touch nothing, wear not at all, and are the nails most likely to curl into the leg.
Should I ignore the joint-strain warnings entirely?
Treat them as unproven rather than disproven. One controlled study in clinically sound dogs is meaningful but not conclusive, and orthopedic specialists do report clinical associations between chronically overgrown claws and digital osteoarthritis. We are reporting where the evidence currently sits.
Clippers or a grinder?
Whichever gets the job done. See the comparison below.
Choosing between a clipper and a grinder
The tools do the same job differently, and the right one depends on your dog rather than the specification.
| LED clipper | Rotary grinder set | |
|---|---|---|
| Best for | Dogs that tolerate a quick, decisive cut | Dogs that flinch at the clip; nervous dogs |
| Dark nails | The LED helps on pale nails and helps less on black ones | Easier to approach gradually — you can stop at the white circle |
| Main drawback | One misjudged cut reaches the quick | Vibration bothers many dogs more than the noise does |
| Watch for | Dull blades crush rather than cut | Friction heats the nail — short bursts only; keep long fur clear of the head |
Introduce a grinder before it touches a nail. Run the motor near your dog for a few sessions first. The most common reason a grinder ends up in a drawer is that it met a paw on day one.
Whichever you choose, buy styptic powder at the same time. We do not sell it — any pet pharmacy or your vet will have it, and cornflour is an emergency substitute.
Browse nail tools and grooming — each page states what the tool suits and where it does not help.
Sources
- Trimming of nails in healthy dogs does not change gait parameters when comparing pre- and post-nail trim. Frontiers in Veterinary Science, 2026. DOI: 10.3389/fvets.2026.1728382
- O'Neill DG et al. — prevalence of disorders recorded in dogs attending primary-care veterinary practices in England (overgrown nails among the most frequently recorded problems, 5.5–7.1%)
- Veterinary guidance on quick anatomy, dark-nail technique and quick recession following chronic overgrowth
- Clinical reports associating chronically overgrown claws with digital osteoarthritis — noted as observational, not experimentally quantified
Written by Kindopet Guides. Reviewed 6 September 2026. General guidance, not veterinary advice. A torn or ingrown nail needs a vet.
