Zachary Thielen, M.D., FAAOS

Orthopedic Surgeon

Dr. Thielen moved to Maui with his wife and children in 2018. He worked as an Orthopedic Surgeon with the Hawaii Permanente Medical Group from 2018 to 2021. Dr. Thielen is the first surgeon to perform and offer direct anterior total hip arthroplasty surgery on Maui. He also helped pioneer the same day discharge program for patients undergoing total joint replacement surgery at Maui Memorial Medical Center.

About the Physician

My grandparents moved from Los Angeles to Lanikai in the 1960s and raised their family on Windward Oahu. I was born in Oregon, grew up on Kauai, and graduated from Waimea High School. While attending the University of Hawaii at Manoa, I was blessed to meet my future wife, a Lahainaluna alumna. After I graduated from the University of Hawaii, John A. Burns School of Medicine, we moved to the mainland for my surgical training, always with the intention of returning to Hawaii to live. I did an internship and residency in orthopaedic surgery at University of California, San Francisco (UCSF), where I was chief resident, and later did a fellowship in adult reconstruction/hip and knee replacement at Hoag Orthopedic Institute in Orange County.Throughout my life my grandmother has been an inspiration. In addition to raising four children, she completed her law degree and dedicated herself to helping the people of Windward Oahu. The example she set led to my choice of a profession that would allow me to make a similar contribution to my community.

About my practice

My undergraduate degree was in civil engineering. I enjoyed this field, but when I was working my way through college at a restaurant in Waikiki, I realized that I wanted to combine my love for the sciences with direct service to others. Medicine was the answer, and, given my engineering background, I was naturally drawn to orthopaedics. The mechanics of muscles and bones are fascinating to me. Being in a position to help patients return to active lives is the most gratifying part of my job. My special interests are minimally invasive total hip replacement, total knee replacement, and partial knee replacement.At UCSF I gave a presentation on orthopaedic surgical care in the country of Malawi. I also spoke on opioid use after surgery at a conference of the American Association of Hip and Knee Surgeons. My research on complications of hip and knee realignment, cartilage repair, bone malformation in children after fractures, and the Keiki Ola Pono Sports Program has been published in several medical journals.To stay current in my field, I attend local and national meetings where the latest research is presented. I also read journals as well as the literature put out by my professional organizations, the American Association of Hip and Knee Surgeons and the American Association of Orthopaedic Surgeons.Getting to know my patients as individuals allows me to tailor a care plan that more closely meets their needs. Whenever possible, I recommend starting off with the least invasive treatments.

My training, Certifications & Licensing

Medical School- UH John A. Burns School of Medicine
Orthopedic Surgery Residency- University of California, San Francisco
Fellowship- Hoag Orthopedic Institute


Alpha Omega Alpha Honor Society recognizes the top 10-15% of students from each graduating medical school class across the nation. AΩA has a strong and long-standing tradition of electing for membership excellent doctors – those who exhibit the highest levels of character, trust, trustworthiness, leadership, professionalism, scholarship, and community service. AΩA members unconditionally represent our motto of “Being Worthy To Serve The Suffering.”

Dr. Thielen did his residency at UCSF Medical Center, which is consistently ranked among the top ten hospitals in the U.S. News and World Report Honor Roll. He then pursued an extra year of fellowship in Adult Reconstruction at Hoag Orthopedic Institute which is nationally recognized as a ‘Best Hospital’ in U.S. News & World Report’s “2020-2021 Best Hospitals” list, placing HOI in the Top 2% of orthopedic hospitals in the nation. At Hoag, Dr. Thielen was exposed to multiple surgical approaches for total hip arthroplasty including the posterior and direct anterior approach.