My tabby is 17 years old. Saturday she was fine, going up and down the stairs, jumping on the furniture and jumping into her favorite bay window. Sunday - she can hardly stand or walk. She is extremely unbalanced. Almost walking in a stoop. Didn't improve on Monday. Took her to the vet yesterday. X-rays showed no broken bones, nothing unusual, just a little arthritis. No pain shown when Dr. examined her limbs. No ear infections. Doctor ran "panel" of blood tests, nothing unusual showed up. So I still have a cat that cannot walk well and no medical reason as to why. If arthritis was the cause, it would not have "set in" overnight like this condition has. Anyone's opinion would be greatly appreciated. The only thing the Dr. mentioned was that her potassium was a smidgeon low, and low potassium can make a cat walk "slope shouldered", but her potassium was not low enough to cause it. Thanks for your time, sorry to be so wordy. Maria in Atlanta, GA