It happened yesterday after I dremmeled his nails. My dog (8 years old beagle mix) stopped using his left hind leg. I checked the paw, everything looked normal. I hoped the problem would resolve on its own by the morning, but it did not. The dog does not put his toes on the ground and basically can't walk. It's hard for him to use only 3 legs when walking. Plus he is overweight.
What can it be? Please help!