I got a new yorkie pup the week of October. I noticed he was pretty clumsy but figured it was due to puppiness. As he has gotten older, he seems to be losing strength in his back legs. Especially his back left leg. He can no longer run, when he gets in a hurry he tends to walk, trot sideways and he falls over a LOT! Vet says it is not a medical problem but perhaps neurological. He is on his 3rd meds now with no effects from them. They were antibotics, then steroids and cortisone. Have recently ordered him some tall shoes in hopes they may help. This problems seems to get worse the older he gets. Anyone ever heard of this before??? HELPPPPPPPPP