Frank A. Ennis, MD

  • College: Yale University, 1988, Post-baccalaureate- Harvard University 1993-1995
  • Medical School: Duke University School of Medicine, 1999
  • Residency: Yale University School of Medicine, 2000-2004
  • Fellowship: Adult Reconstructive Surgery; New England Baptist Hospital, 2004-2005
Frank Ennis, MD, specializes in hip and knee replacement, hip arthroscopy, complex revision arthroplasty of the hip and knee, and treatment of complications from hip fractures. He is fellowship-trained in adult reconstructive surgery. Dr. Ennis is a staff orthopedic surgeon at Greenwich Hospital and was among the first orthopedic surgeons in the New York Metropolitan area to do computer-assisted surgery for total knee and hip replacement. This cutting edge technique uses computerized navigation to guide the surgeon for improved accuracy in joint replacement surgery.

Further, after completing undergraduate studies at Yale University and post-baccalaureate pre-medical studies at Harvard University, he graduated from Duke University School of Medicine and completed his residency at Yale University Department of Orthopaedic Surgery. Additionally, Dr. Ennis completed Fellowship training in adult reconstructive surgery at New England Baptist Hospital in Boston,  MA.


Computer-assisted surgery is the newest generation of technology in joint replacement. Surgeons create a visual map of the knee using a highly-precise image guidance system that allows the surgeon to see beyond the ability of the naked eye. With infrared cameras and digitized images, every aspect of the operation is tracked by computer including instrumentation and positioning of the implant. More precise alignment of the implant leads to better range of motion and long-term results.

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On the first anniversary of the second hip replacement, I wanted to write to formally thank you. I feel great. Play golf regularly. Exercise everyday when I don’t golf. Am strong, and have achieved much greater range of motion that I ever thought I would. In short, happy all around. (Letter from J.O.)

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Dr. Ennis discusses Total Joint Replacement surgery in the videos below:


American Academy of Orthopaedic Surgeons
American Association of Hip and Knee Surgeons
Connecticut Orthopaedic Society
Yale Orthopaedic Association


American Board of Orthopaedic Surgery


Castle Connolly Top Doctors 2013-2020
Connecticut Magazine Best Doctors 2020
Greenwich Magazine Top Doctors- 2013-2020
Stamford Magazine Top Doctors- 2013-2020
New Canaan/ Darien Magazine Top Doctors- 2013-2020
Westport Magazine Top Doctors- 2013-2019