Hard to say, could be Hip, Stifle, or Knee (ACL) was there any other stainuous activity prior to the running. I've seen dogs come up lame after a hard romp in the backyard.slid3r said:For a couple weeks I started to run my dog along my bike for about a mile. After about a month she started limping on her back leg. She randomly would not walk on it for a few seconds, then she will be perfectly fine. I've been taking her on walks on the grass now to ease the pressure, but she still has periods of a few seconds where she will walk on only three legs.
It's not a constant thing and she shows no signs of pain as she can still run full speed, so I'm really lost.