I'm so sorry to hear about Joey.  Our tripawd, Hunter, is 12 1/2 and was just diagnosed with a fracture in an osteosarcoma in her right rear leg a couple days before Christmas.  She is also a large dog - 80lbs pre-amputation.  After thorough exams by an oncologist and orthopedic surgeon it was recommended to us that she was a good candidate for amputation and treatment (this was in contrast to our general vet who recommended euthanasia).  She had her leg amputated a week ago.  Ultimately I think you know Joey best and, once you have all the medical facts necessary to make a decision, you can factor in Joey's attitude and spirit.

I also highly recommend glucosamine supplements, fish and flax seed oil and a good diet for Joey's arthritis.  Years ago I had a senior Lab girl who was diagnosed with significant arthritis in her spine and joints at the age of 11.  We switched her to a raw diet, added glucosamine and other supplements and she did extremely well for years.  Around the age of 15 we started her on Adequan injections (essentially injectable glucosamine) that really seemed to help and threw in a few chiropractic adjustments and acupuncture for good measure (also seemed to help).  She lived comfortably until she was almost 17.

Back to the older dog amputation questions... Hunter was in less pain immediately after her surgery than she was the days before the surgery.  Within minutes of waking up from anesthesia she took the tech for a walk (a drag according to the tech) outside and has been hopping along ever since.  We've been using a towel under her abdomen/hind end for support in case she loses her balance but she doesn't need it.  The first couple of days she was a bit wobbly but that was more due to the pain meds than anything else.

We were fortunate with Cooper and he didnt seem to have a lot of pain after either of his surguries. If he did , he hid it extremely well, he fell several times right on his incision and never let out so much as a whimper. When you say walked reliably , thats kind of a tugh one to pinpoint, Cooper began to walk with help about 3 days after post op, and Im going to say it was probably 5 to 7 days before he walked on his own much

( except for his excercise sessions all night long in his pen) he never did well on slick surfaces even with 4 legs , which is one of the reasons that they didnt consider him a good candidate for amputation, they saw him slip and fall on the marble slick floors at the vet and struggle to get up again , which was normal for him, it wasnt until after he became a tripawd that I learned they had any kind of traction boots for dogs , which he now has a set for when we go out where there will be hard slick surfaces.

By two to three weeks post op he was walking pretty reliably on his own although he tired out easily. At 2 months post op, it is difficult to tell a difference in how he gets around with the exception of taking stairs a lot slower, but he goes up down completely on his own. Harnesses are rarely used anymore at all. We were also fortunate that Cooper never experienced any phantom pain. As littlemanjake said, all dogs are individuals and no two probably respond exactly the same.

The main thing to bear in mind is that after the amputatin you probably have a minimum of two weeks that are going to be really tiring, discouraging and tough, times when you sit on the ground and look at your fur pup and wonder what you have done. But stand fast because that time goes by faster than you can imagine and all of a sudden you are wondering why you ever worried. Our vet also said that Coopers mass didnt present itself like cancer, and that it was in a funny place, after the x ray he felt it probably was cancer, and we opted to do the amputation, even if it wasnt cancer, Cooper is so much healthier now than he has been. Hopefully this helps you in some way.

Coopsdad