Dr. Gersten is from Lakewood, New Jersey. He attended Stanford University, graduating with a B. S. in Biology. He attended medical school at Jefferson Medical College and interned in General Surgery at Pennsylvania Hospital, both in Philadelphia.

He returned to the West Coast for his residency at Los Angeles County, University of Southern California. He fellowship trained in total joint replacement and reconstructive surgery at Joint Implant Surgeons, Ohio State University. Dr. Gersten practices general orthopedics with specialization in sports medicine and arthroscopy, arthritis and joint replacement surgery. He is team physician for Santa Margarita High School. Dr. Gersten came to the Saddleback community in 1988.