So it WAS Tim McCarthy, although my phone apparently corrected it to McArthur.
He was really great. I only met him a couple times, for the initial consult and then on the actual surgery day, but was very impressed. I was also inclined to trust him because not only does Riddle's ortho vet love him, our regular vet used to work with him and had nothing but good things to say. He did an amazing job on Riddle's elbows, he apparently really pioneered the procedure he did on them.
This is the clinic he works at in Portland, although it appears you'd have to get a referral to go there. http://www.cascadevrc.com/
I don't know if he's the best Portland's got, but he sure did a great job with Riddle. Worst comes to worst, I'd say drive on down to Bend and talk to Mark Parchman. He did both Riddle's knees and is absolutely amazing. I would never go anywhere else for ortho issues unless he refers me like he did with Dr. McCarthy.