Start with whether the leg bears weight
The most useful first question is not how dramatic the limp looks, but whether your dog will put weight on the leg at all. A dog who holds the leg up completely, cries out when it is touched, or cannot rise comfortably needs to be seen the same day. So does any limp that follows a fall, a road incident, a bad landing from furniture, or a collision with another dog, even if your dog seems brighter an hour later.
Why the pattern of a limp matters
A front-leg limp often shows as a head bob as the sore leg lands, whereas a hind-leg limp may show as hip sway, bunny-hopping, or reluctance to sit squarely. Puppies can limp from growth-related pain or a knock during play, large breeds can strain a joint carrying weight at speed, and older dogs may have underlying joint disease unmasked by one awkward twist. Your vet needs that pattern, because a soft-tissue strain, a paw injury, a joint problem, and a bone injury can all present as the same uneven gait at first glance.
Check the paw before you assume it is the leg
Before the appointment, look carefully at what you can see without forcing anything. Check between the toes and pads for a cut, a thorn, cracked skin, a swollen toe, or a broken or bent nail, and look for grass seeds lodged in the fur around the foot. Note any swelling along the leg, heat compared with the other side, or a spot your dog pulls away from when you approach it. Do not press deeply, bend joints to test them, or give human pain relief, which can be unsafe for dogs and can mask the very signs the vet needs to assess. A short phone video of your dog walking slowly on a flat surface, filmed from the side and from behind, is genuinely useful evidence.
Rest properly while you wait to be seen
Rest means leash walks only for toilet breaks, no stairs where you can avoid them, no jumping on or off sofas, and no off-leash running even if your dog seems keen. Use a harness or support sling only if your vet advises it for your dog's size and injury, and keep slippery floors covered where possible so the sore leg is not splayed. Feed and water should be easy to reach without a climb.
What the vet will examine and why timing helps
At the visit the vet will watch your dog walk, feel along the leg comparing both sides, check joint movement gently, and examine the paw and nails in detail. Depending on what that examination finds, imaging may be recommended to look at bones and joints that cannot be judged from the surface. Earlier assessment usually means a clearer picture, because a dog who has been compensating for weeks develops soreness elsewhere that muddies the original problem.
Building a recovery record you can refer back to
Limping episodes often recur in active and aging dogs, and a written history prevents each one being treated as a mystery. Note the diagnosis or working explanation, the rest period advised, when normal walks resumed, and whether the limp returned at a particular level of exercise. Over time that record can show a pattern, such as a left hind limp that follows hill walks, that no single visit would reveal. KinsLe's Pet Passport keeps those leg notes, previous injury history, and vet findings together for a limping dog, so the next episode starts from evidence rather than recollection.