So far so good for my hips and knees, but my father has had a knee done and my uncle both hips...many years ago. Now the uncles knees were back when Jeep was making the parts! He walks fine and has no really issues, but nothing like a Karate work out for him. He was already easy chair bound when he had them both done, two years appart. He said the best thing was it got him to eat right to drop some weight because the lighter he was the better the surgery went for the second one. He dropped 30 pounds for the second hip, granted he could have done more.
Good luck man and remember that they say the sooner you get back to light exercise the better and the more active you are the better as well.
Even monkeys fall from trees