Dr. William Sima

Orthopedic Surgeon,Director, Posada Surgery Center

Dr. William Sima

Dr. William Sima graduated from the University of Southern California in 1981 with a Bachelor’s Degree in Biological Sciences. He earned his Doctor of Medicine from USC in 1985.


Dr. Sima continued his training at the USC Medical Center in Los Angeles County and completed his internship in orthopedic surgery in 1986. After a residency in orthopedic surgery in 1990, Dr. Sima completed a fellowship in foot and ankle surgery at Harbor UCLA Medical Center, Los Angeles, California.


Dr. Sima has a private orthopedic surgery practice in Templeton, California, where he also serves as Medical Director of the Posada Surgery Center. Dr. Sima is active in the Central Coast community, serving as the volunteer team physician at Atascadero High School for over 25 years. Volunteer work has taken Dr. Sima on medical missions to Mexico, India, Peru, and Indonesia. He additionally volunteers for the sheriff’s department aerosquadron that assists search and rescue and organ transplants.


In his free time, Dr. Sima enjoys taking photos as a professional photographer and enjoys traveling, tennis, golf, flying, and wine tasting.


Dr. Sima has three children: one is an accountant, another is studying for her master’s degree in nursing, and one is studying to be an engineer.


Visit Dr. Sima’s private practice website here.


Dr. Sima in the news

SLO NewTimes: Home by dinner: Dr. Sima offers orthopedic replacement surgeries without overnight stay


Sports medicine
Anterior cruciate ligament reconstruction
Rotator cuff repair
Shoulder instability
Carpal tunnel surgery
Foot reconstruction
Minimally invasive knee and hip replacement

Research & Interests

Fractures involving hip and femur
Carpal tunnel syndrome arthritis of the foot

Board Certifications

Diplomat, American Board of Orthopedic Surgery
Fellow, American Academy of Orthopedic Surgery