About Us

Our Physicians

Lawrence D. Dorr, M.D.

Medical Director
Total Joint Reconstruction
Dorr Arthritis Institute
Good Samaritan Hospital

Lawrence D. Dorr, M.D., Founder and Medical Director of The Arthritis Institute, he has performed more than 3,500 hip and knee replacements in the past decade,

Dr. Dorr has the honor of being President of the Hip Society this year. The Hip Society is the most prestigious organization for hip surgeons and researchers and has 100 members. Dr. Dorr also has been President of the Knee Society, the sister Society of the Hip Society which has membership of 100 of the leading knee replacement surgeons and researchers; and of the American Association of Hip and Knee Surgeons which has a membership of 1000 hip and knee replacement surgeons in the United States. He was a founder of both the Knee Society and the American Association of Hip and Knee Surgeons. He is the only surgeon to be a member of all three organizations.

Dr. Dorr has been honored by his colleagues for his accomplishments during his career:

He began designing implants for the benefits of patients in 1982. The APR stem was first marketed in 1984 and remains in use today with the shape and fixation surface unchanged since the early 1990s. The Apollo knee replacement was marketed in the early 1990s. He sold his intellectual property to Sulzer Orthopedics (now Zimmer, Inc, Warsaw, IN) for millions of dollars for which he is still being paid by Zimmer (until 2010). Currently, he has merged his knee technology with Aaron Hofmann, who designed the Natural Knee. He is currently designing a new hip prosthesis with Zimmer which is a short stem, minimally bone invasive hip replacement. This design is a ÒsonÓ of his original short stem bone preserving design used in 1983 with results published in 1984 in the journal Contemporary Orthopedics. This preceded the minimally invasive surgery movement by twenty years.

Dr. Dorr was one of the first surgeons to use hydroxyapatite as a fixation surface on hip implants. He implanted the first HA coated stem in 1983 and has published several articles on this fixation surface.

Dr. Dorr reintroduced metal-on-metal into the United States in 1991. He implanted these as custom implants and with an FDA study until 1996. After being reprimanded by the FDA for an irregularity in that study, metal-on-metal was stopped until 1999 when approved by the FDA. Dr. Dorr, with Dr. Long, has more articles published on clinical use of modern metal-on-metal than any other surgeon/researcher.

The first article of five year results on success and low wear of highly crossed-linked polyethylene was published by Dr. Dorr and the research team of the Arthritis Institute in the Journal of Bone and Joint Surgery in 2005.

The posterior minimally invasive surgery operation designed by Dr. Dorr has been the most studied and most successful minimally invasive surgery total hip replacement by published reports (he was not the first surgeon to do posterior MIS, but his incision has been studied the most). His articles, including a randomized study published in Journal of Bone and Joint Surgery in 2007, have confirmed the findings of others with this incisional approach to total hip replacement. His book is the definitive text which describes the technique of this operation.

Dr. Dorr is the leading clinical researcher for computer navigation for total hip replacement. His data has proved the accuracy of using navigation for implanting the acetabular and femoral components and restoring correct leg length and offset for the hip. This technology, combined with the use of large femoral heads, essentially eliminates impingement which improves stability, reduces wear, loosening, and pain with total hip replacement. The first of three articles detailing the results is published in Clinical Orthopedics and Related Research in December 2007. The founding article on the initial research is published in the Iowa Journal of 2005 which was the 25th Anniversary of that journal (the volume was dedicated to Dr. Dorr). The technique of computer navigation is detailed in Dr. DorrÕs book Dorr LD: Hip arthroplasty. Minimally invasive techniques and computer navigation, 1st edition. Philadelphia, PA, Saunders Elsevier, 2006.

The research team at the Arthritis Institute is one of the top 5 research centers in the world for total hip replacement. For example, in 2007 this team has published more articles on total hip replacement than any other of the academic centers in California. In the three most prestigious journals, the Arthritis Institute has been in the top 3 contributors. The research team has received several hundred thousand dollars in support from Zimmer, and from our many patient supporters.

One of the most successful meetings to educate orthopedic surgeons on techniques of total hip replacement and total knee replacement has been the Masters Series meeting held annually. Founded by Dr. Dorr while he was a professor at the University of Southern California, it is now in its 15th year of educating surgeons. It receives financial support from Zimmer and is supported by DePuy, Stryker, Smith and Nephew, and Biomet, and a host of other orthopedic companies (see Masters Series under research and education on this web site) for its educational value. Participants pay for their attendance.

Dr. Dorr has been blessed by his accomplishments and contributions to medicine and to patients. He gives thanks to God for the opportunities to fulfill his potential. He and his wife Marilyn have been philanthropic with their money made from his work. They have donated $2 million to the University of Iowa, Department of Orthopedics for a Chair in hip surgery; they founded the Dimensions Program at Cornell College which is a unique program for pre-med and pre-health care worker students to learn the importance of the art of caring for patients, including psychology, communication, literature, and art courses, as well as hands-on internships. They fund that at $300,000 per year. Their favorite charity is Operation Walk, an organization Dr. Dorr founded in 1994 with Jeri Ward, R.N. as the coordinator and Mary Ellen Sieben as the operating room director (see Operation Walk on this web site). Perhaps this organization, and the psychological benefit it gives to every doctor, nurse, therapist, technician, and lay-person who participates, is the greatest contribution of Dr. Dorr to the orthopedic community, and international society. He was recognized for Operation Walk as the Humanitarian of the Year in 2006 by the American Academy of Orthopedic Surgeons in Washington, DC.

Next Physician