Jennifer,
I am so sorry you and Lincoln are dealing with this. He is such a cutie. As actve as he is, I don't thinnk you'll have to worry about him not moving I will be interesting in what the other vets have to say.
Although he is not a GH, my daughter's friend is going through this with a lab puppy. He is only 10 months and it is really bad. They are faced with weighing his quality of life, ie pain, vs their deep love for him. I don't believe they can afford a hip repalcement, and they are scared that they won't be abe to manage his pain. He waited a long time to find his home. He was the last of the litter to go, and now this.
I am hoping for the best possible outcome for both these babies.