I really have to disagree with the other two posters. Older dogs with severe arthritis do suffer, and even with medications from a vet their condition will not be cured,and in some cases they may not even help at all. I have known several elderly dogs with the same problems but they have been much older, 14 or 15 year old labs, 9 does seem a bit young which is really very sad. I would say that if you have not seen your vet lately make an appointment and feel them out on the best way to handle the situation, perhaps something else is happening other than the arthritis. If it is the arthritis I would hold off putting her down until shes actually in serious pain. This would be if not only could she not walk but she was constantly whining in pain when she tried to get up. Just try to make things easier for her, give her boosts onto the bed and sofa, give her a raised feeder for her food, do things like you might do for an elder person.