The IETSS (formerly IITS and IITTSS) is a 501C3 non-profit organization whose focus is on intradiscal therapy aided by the endoscope as the least invasive, visually-guided treatment for discogenic pain.

The International Endoscopic Therapeutic Spine Society (IETSS), formerly the International Intradiscal and Transforaminal Therapy Society (IITTSS) and International Intradiscal Therapy Society (IITS), was founded in 1987 and is now headquartered in Phoenix, Arizona.

Xifeng Zhang’s Yeung Society Statement

From the desk of Anthony Yeung, MD
Executive Director of

New sub-societies are being established in China and Taiwan, as I step up training all over the world. One such society is the "Yeung Fellow’s Endoscopic Spine Society," in China made up of my spine fellows and other physicians who are embracing the YESS endoscopic technique. A parallel "Academic Yeung" is also being formed for the Taiwanese Spine Surgeons currently being trained by me.

Below you will find excerpts from a personal message from the President of the "Yeung Fellow’s Endoscopic Spine Society," Xifeng Zhang, M.D, PhD. about his encounters as both student, teacher and practitioner of MISS endoscopic techniques, as well as the values, beliefs, and establishment of the "Yeung Fellow’s Endoscopic Spine Society." I encourage you to download and read the full statement.

Anthony Yeung, MD

Excerpts from: "A Master Surgeon in Spine: Minimally Invasive Spine Surgeon (MISS) with Charisma―The Anthony Yeung that I Know. "

by Xifeng Zhang, M.D, PhD. | Translator: Catherine Liu (刘炳蕙)

"I met Anthony Yeung during the 2001 Beijing Spine Surgical New Technique Development Workshop on September 21st, 2001. New spine surgical techniques, at that time, were primarily internal fixation techniques, so I was not originally deeply impressed by Anthony Yeung at first. It was fortuitous that I recorded the lectures with a digital camera and summarized his talk in my spare time, thus saving his lecture content. I recognized later that the technique described by Dr Yeung had merit for minimally invasive access to the lumbar spine and for limiting the surgical morbidity of open surgery. I started treatment for percutaneous spinal tuberculosis in January 2002 and started utilizing percutaneous lumbar discectomy guided by CT in July 2002. I encountered a postoperative infection case and realized that I should no longer “mess around” without seeing the internal pathological situation. It was at that time that I realized the master was just across the ocean and I did not hesitate to seek him out as my teacher. This was the start of learning from Dr Yeung in October 2003."

Update: IITTSS now IETSS

From the desk of Anthony Yeung, MD
Executive Director of (formerly and )

Spinal Therapies announced its dissolution after the company determined that it is unlikely to ever regain profitability since the early days when chymopapain was promoted by the likes of Eugene Nordby, who is still alive and thriving as the first Executive Director of IITS.

I took over IITS at the request of Dr. Nordby and maintained an emphasis on the Organization’s focus on Intradiscal therapy aided by the endoscope as the least invasive, visually-guided treatment for discogenic pain.

Intradiscal therapy is still the only Level I validated EBM. Unfortunately, events adversely affecting Pharma and Surgical company profitability have caused both entities to turn toward the more profitable implant and hardware devices to follow the money and the road to profits.

We have, however, a core of highly trained and dedicated surgeons who recognize the future of spine care who are are lifetime members of IITTS, and each proudly wears the wears the Gold IITS pin on their lapels at spine meetings, still promoting Intradiscal therapy through an endoscope.

IETSS Leadership

Anthony Yeung, MD
Executive Director

James Yue, MD

Girish Datar and Luke Kim
Co-directors of Medical Education