Our dear Landseer Newf Memphis is going for knee surgery today. The problem is with her cruciate ligament, which has deteriorated considerably and is causing her a lot of pain on her rear right side. Left unchecked, it will severely limit her mobility. As part of the surgery the specialist-vet will reshape the top of the tibia and put a stainless steel plate in which will help hold things together while she heals. Memphis will have significantly limited mobility for the next two months and somewhat limited mobility for a month after that. She should be home from the clinic tomorrow. Her and I will be on the limp together.
Update: Memphis is out of surgery and recovering. We expect she will be able to come home sometime tomorrow.

Apparently it is fairly common in large dogs. She has been increasingly been limping on the rear right.
Poor girl. Did she injure herself or is this a common condition amongst Newfs? Hopefully both of you will mend quickly!