Antony T. Yeung is the founder of the Arizona Center for Minimally Invasive Spine Surgery, the inventor of the Yung’s Endoscopic Spine Surgery (YESS) system and the creator of the YESS technique. He is an internationally renowned expert in minimally invasive spine surgery. During the 3rd National Orthopaedic Congress COA, I conducted an interview with Antony T. Yeung on November 13, 2008, commissioned by the Orthopaedic Branch of the Chinese Medical Association. What motivated your interest in minimally invasive spine surgery and your continued practice of minimally invasive spine surgery? A: When I was a resident, my mother suffered from a lumbar disc herniation and underwent traditional open surgery to remove the lumbar disc in the hospital. At that time, arthroscopy had been clinically used, and there were many patients with arthritis whose lives were significantly improved by the advent of arthroscopic surgery to avoid joint fusion surgery. This led to my interest in endoscopic surgery, and I later had the opportunity to learn the technique of arthroscopic lumbar disc removal from Professor Kambin in Philadelphia, after which I practiced minimally invasive spine surgery. In the 1990s, I invented the YESS (Yeung Endoscopic Spine Surgery) system and established the YESS technique. Since then this technique has been applied to the diagnosis and treatment of lumbar disc herniation and discogenic low back pain. Many patients have been cured through minimally invasive surgery, which is why I have been engaged in the clinical application and promotion of this technology. Q: Professor Yeung, what do you think are the factors that have contributed to the rapid development of minimally invasive spine surgery in the last three decades? In particular, in the treatment of lumbar disc herniation? A: First, patient demand is the premise for the development of minimally invasive spine surgery. Due to the inherent limitations and risks of existing traditional open spine surgery, some patients experience complete short-term symptom relief after traditional open lumbar spine surgery, but in the distant future, recurrence of persistent symptoms in the lower extremities and lumbar region, often with no positive imaging findings. Failed Back Surgery Syndrome (FBSS), but there is nothing doctors can do about it. There is growing evidence that extensive adhesions in the spinal canal following transforaminal surgery may be a significant factor in the long-term outcome of open spine surgery. Failed lumbar spine surgery has led patients to fear traditional open surgery and seek minimally invasive surgical treatment. Second, the efforts of spine surgeons have been the driving force behind the development of minimally invasive spine surgery techniques. The YESS system invented by my team makes the technique simpler, more effective, and easier to promote. Of course, modern imaging technology, optical equipment and digital transmission technology are necessary to achieve minimally invasive surgery. Q: As the inventor of the YESS system and technology, would you please briefly introduce the YESS technology and its advantages over traditional open disc removal? A: The YESS system includes, puncture instruments, coaxial rod endoscope and a series of microscopically operated surgical instruments (including various pulpal forceps, laser and radiofrequency devices). The YESS technique has no damage to the paravertebral muscles, no damage to the stability of the spine, and no postoperative adhesion formation in the spinal canal because the operation does not enter the spinal canal; timely operation If the operation fails or the disc herniation recurs after the operation, it will not affect the efficacy of the reopening operation and will not increase the difficulty of the reopening operation. Q: Among the percutaneous foraminoscopic lumbar disc removal techniques, there are two types of techniques that are currently the most popular: the YESS technique is a surgical technique that uses the YESS system to gradually remove the disc from the inside out, while the THESIS technique is a technique that uses the JOIMAX system to make the endoscope enter the spinal canal directly for targeted removal of herniated disc tissue by assisting in the enlargement of the intervertebral foramen. Can you compare the advantages and disadvantages of these 2 techniques? A: The THESIS technique has theoretical advantages in dealing with herniated displaced and free lumbar disc herniation and can perform targeted resection of the prolapsed disc tissue, but in the JOIMAX system, the annular saw is operated outside of the trocar and it is easy to involve the soft tissues and nerve roots around the intervertebral foramen resulting in injury. Moreover, the bleeding after the endoscope enters the spinal canal is difficult to control, and the canal is prone to adhesions after surgery; moreover, for contained lumbar disc herniation, lumbar foraminoplasty is not required. For the herniated free type, a decompression cavity can be created in the disc first, and then the herniated or prolapsed nucleus pulposus can be removed under endoscopic surveillance using a head-flexible nucleus pulposus forceps; for cases requiring foraminal enlargement, a high-speed grinding drill or circular saw can be used under endoscopic surveillance and the protection of a working cannula. The YESS system can also be used to perform total endoscopic lumbar disc removal from the posterior via the spinal canal. Since the working area of the YESS technique is the intervertebral foramen, visualization of pathological changes in the foraminal area can be obtained, and pathological changes such as foraminal stenosis, disc rupture, and abnormal nerve fiber proliferation can be detected and effectively treated endoscopically. Therefore, the YESS technique is safer than the THESIS technique and has a wider range of indications than THESIS. Q: Professor Yeung, what advice do you have for Chinese surgeons practicing minimally invasive spine surgery to successfully and safely pass the steep learning curve of the YESS technique? A: Theoretical learning is very important, including learning the basic theory and techniques from traditional textbooks and the latest advances in the latest journals, becoming familiar with the anatomy of the lumbar spine, especially the anatomy of the lumbar safety triangle, and memorizing the key points and theoretical basis of various techniques; formal clinical observation, cadaveric training, and then transitioning to clinical use; clinical indications must be chosen from easy to difficult, starting with discography -Intradiscal decompression – contained lumbar disc herniation – herniated and displaced lumbar disc herniation – free lumbar disc herniation; persevere and never give up. Q: What is your outlook on the future of YESS technology in clinical use? What are your comments and suggestions on the current status of minimally invasive spine surgery in China? A: As the operator’s mastery of YESS technology and surgical experience increase, YESS technology can also be used to diagnose and treat discogenic low back pain (selective lumbar disc removal, radiofrequency thermocoagulation fibrous annuloplasty); to treat lumbar lateral saphenous stenosis (lumbar foraminoplasty); to treat recurrent lumbar disc herniation; artificial lumbar disc nucleus pulposus replacement; percutaneous transvertebral foramen lumbar interbody fusion, etc. Under the leadership and support of the Chinese Orthopaedic Society headed by Academician Qiu Guixing, minimally invasive spine surgery in China has been developing rapidly, and we believe that the cause of minimally invasive spine surgery in China will be better tomorrow!