Knee Replacement X-Ray

Experience counts. Technology matters. Personalized care is essential.

With over 30 years combined experience in advanced hip and knee treatment, Doctors Diana and Shifflett combine their subspecialty expertise with modern minimally invasive techniques and leading technology in conducting more than 400 surgeries per year with proven patient outcomes and longterm results.

Our commitment to providing an individualized treatment plans for each Napa Valley Joint Replacement Center patient is reflected in our practice philosophy:

1) Assess each patient thoroughly
2) Develop a personalized treatment plan
3) Select the highest quality implant based on individual patient needs
4) Avoid economic conflicts-of-interest that can lead to poor medical decision making
5) Be attentive to individual patient needs before, during, and after the surgery
6) Maximize doctor-patient communication throughout treatment

Meet Dr. John N. Diana, M.D.

Meet Dr. Michael W. Shifflett, M.D.


I was already dealing with severe back and neck pain when my first knee began giving me trouble.It got to the point where it was painful to stand, let alone walk. Dr. Shifflett first used non-operative care which helped greatly with the pain but in time I needed knee replacement. Dr. Shifflett and the staff at the Queen were amazing – walked me through every step of the joint replacement process, and really prepared me for what to expect.

Following surgery, the Queen physical therapy staff had me walking almost immediately, and eventually doing my physical therapy in the pool which I prefer – it’s more fun and you’re weightless! It all went so well, and I recovered so quickly, that when my other knee needed to be done a year later, I had no fears and Dr. Shifflett was right there with me. The same was true the year after that when one of my hips needed to be replaced, again Dr. Shifflett and the Queen guided me through it. And the same will be true when my other hip goes…. And I feel fully prepared!”

Diane Sarant, Napa
Total Knee & Hip Replacement

My right knee had grown worse over the years to the point where I couldn’t kneel down or get up easily. When I first started seeing Dr. Diana, he gave me injections that lessened the pain. After a while the injections stopped working and I knew it was time. Dr. Diana explained how using computer navigation helps him make the most accurate measurements, resulting in successful knee replacement.
I believe Dr. Diana’s surgical skills and then my commitment to post-surgery rehab quickened my recovery. Dr. Diana had me using the CPM machine immediately after surgery and I stuck with it – and am now back to doing all the things that I want to do.”

Angela Pieper, Napa
Computer Navigated Knee Replacement