Do was 18 recently, in good health apart from problems pooing in recent months for which she has 4.5ml lactulose/ day which has helped but not solved the problem, she has lost a little weight but seems ok. Twice recently she has developed a limp and then when she sits her paw sort of folds over so the front of her ankle joint is on the ground. She has no pain in the area and it goes after a day or two. I'm reluctant to take her to vet unless really necessary as she is so traumatised by going. It looks like a nerve problem to me (from watching supevset) and I'm wondering if it's linked to the bowel issues. - is it just age or something worse?