When your dog shows signs of stiffness or lameness it can be difficult to tell if the problem is neurological or due to arthritis. Your veterinarian will want to do a complete workup on your dog to properly diagnose the problem and help him to determine the best course of treatment, but that takes time. If your dog is in pain or seems frightened because he’s struggling to walk or to maintain his balance, a preliminary diagnosis can help your vet start treatment immediately or to know where to start the testing process.
Testing
A quick way to check what’s behind your pup’s problem is for your vet to hold your dog under his hind legs to support most of his weight and take one of your dog’s paws and fold it over so that he’s bearing weight on the top of his foot rather than the bottom. If your pet tolerates this awkward “knuckling” position even briefly, he may have a neurological problem because he isn't feeling his foot properly. Quickly returning his paw to its normal position doesn’t rule out neurological damage. It's possible he has arthritis. Your vet likely will do more testing.