Yingda Li and Michael Wang consider the increasing interest in endoscopic techniques in spinal surgery. The authors describe how endoscopic techniques have been incorporated into practice at the University of Miami, and discuss how they can be used successfully alongside other emerging surgical techniques.
Whilst the history of endoscopic spinal surgery dates back to the 1970s, it was not until recently that it started to garner attention and gain traction in North America. Over the last few years, coupled with burgeoning patient demand for minimally invasive surgery (MIS)10, evolving resource allocation patterns within US health systems12, and a historically unmet need to care for the elderly and infirm11, several landmark advances have been made in the field of endoscopic spinal surgery, some of which have been pioneered at the University of Miami.
Percutaneous approaches to the intervertebral space were first described by Kambin in the 1970s, through the eponymous Kambin’s triangle1. Initial approaches remained percutaneous and visualisation indirect, and it was not until a decade later that the first endoscopic views of the intervertebral disc were achieved2. Since then, numerous iterations and improvements in equipment and technique have occurred, although the practice of endoscopic spinal surgery has remained relatively dormant in North America, particularly in comparison to our colleagues in Asia3.
Its widespread acceptance and uptake has perhaps been in part hindered by parallel explosions in other potentially more lucrative fields within spinal surgery, such as instrumentation, expandable technologies, biologics, navigation, and robotics4. Furthermore, the unfamiliar equipment, approach and view afforded by endoscopic spinal surgery have led to steep learning curves
and deterred many surgeons away from this field, particularly if perceived effort is unmatched by proportionate remuneration.
Over the past five years or so, increasing recognition of the physiological footprint imparted upon the patient by traditional open surgery, combined with a historically nihilistic approach to operating upon the elderly and infirm, a population that often needs our help the most, and traditionally negative public perceptions of spinal surgery, have led to the rise of enhanced recovery after surgery (ERAS) programmes, with endpoints of reducing pain and narcotic consumption, hastening postoperative mobility and recovery, improving patient satisfaction, and reducing length of stay and costs5. At the University of Miami, we have eliminated one of the key physiological stressors, the general anaesthetic, replacing it with conscious sedation, and applied it to lumbar fusion, resulting in the first-in-man awake endoscopic MIS transforaminal lumbar interbody fusion (TLIF), leveraging long-acting local anaesthetic, expandable interbody technology, biologics, and percutaneous instrumentation6, a feat not long ago considered improbable, if not impossible (Figures 1-3).
Indications for endoscopic spinal surgery have continued to broaden and evolve, with stenotic, spondylolisthetic, other degenerative and even tumoural pathology across the entire length of the spine now treatable endoscopically9. At the University of Miami, we have introduced endoscopic techniques to treat complex spinal deformity, ranging from limited, strategic decompressions at the fractional curve on one end of the spectrum7 to efficient, multi-level endoscopic MIS-TLIFs as a workhorse in long-segment constructs. Whilst the exponential development in navigation and robotics has perhaps in some ways occurred previously at the expense of endoscopy, we view these technologies as complementary and potentially synergistic, flattening some of the learning curve associated with traditional fluoroscopic-guided endoscopic spinal surgery approaches and increasing their safety and reproducibility.
The time is now for spinal endoscopy, and its future bright. The growing interest in this field is only perhaps matched by its expanding indications, the recognition of the need for techniques that not only minimise iatrogenic anatomical disruption but also the physiological stress imparted upon the patient, and our responsibility to offer hope to patient populations historically denied surgery. There is already randomised trial evidence supporting endoscopic over traditional microdiscectomy approaches8, and as visualisation, instrumentation, and technology continue to improve, there is no reason why endoscopic spinal surgery cannot gradually supplement or succeed other approaches, in the same way that endoscopic anterior skull base surgery has, in many respects, superseded traditional microscopic pituitary surgery and morbid open skull base approaches.
Yingda Li is a spine fellow at the University of Miami Miller School of Medicine (Miami, USA). His research covers all aspects of spinal surgery, in particular minimally invasive surgery, intradural surgery, and spinal deformity.
Michael Wang is the chief of Neurosurgery at the University of Miami Hospital (Miami, USA). His clinical interests include minimally invasive spinal surgery, intradural spinal surgery, spinal deformity, clinical outcomes, and trials, and spinal cord injury.
Disclosures: Michael Wang serves as a consultant to DePuy-Synthes Spine, Stryker, Spineology, Aesculap Spine, JoiMax, and K2M; receives royalties from Children’s Hospital of Los Angeles, DePuy-Synthes Spine, Springer Publishing, and Quality Medical Publishing; holds stock in Innovative Surgical Devices, Medical Device Partners, and Spinicity; and receives grants from the Department of Defense.
- Kambin P (ed): Arthroscopic Microdiscectomy: Minimal Intervention Spinal Surgery. Baltimore, MD: Urban & Schwarzenberg, 1990.
- Kambin P, Nixon JE, Chait A, Schaffer JL. Annular protrusion: pathophysiology and roentgenographic appearance. Spine 1988;13:671–675.
- Lewandrowski KU, Soriano-Sanchez JA, Zhang X, et al. Regional variations in acceptance, and utilization of minimally invasive spinal surgery techniques among spine surgeons: results of a global survey. Journal of Spine Surgery 2020;6:S260–74
- Yoon JW, Wang MY. The evolution of minimally invasive spine surgery. J Neurosurgery Spine 2019;30:149–58.
- Dietz N, Sharma M, Adams S, et al. Enhanced recovery after surgery (ERAS) for spine surgery: A systematic review. World Neurosurg 2019;130:415–426.
- Kolcun JPG, Brusko GD, Basil GW, et al. Endoscopic transforaminal lumbar interbody fusion without general anesthesia: operative and clinical outcomes in 100 consecutive patients with a minimum 1-year follow-up. Neurosurg Focus 2019;46(4):E14.
- Madhavan K, Chieng LO, Mcgrath L, et al. Early experience with endoscopic foraminotomy in patients with moderate degenerative deformity. Neurosurg Focus 2016;40(2):E6.
- Gibson JNA, Subramanian AS, Scott CEH. Erratum to: A randomised controlled trial of transforaminal endoscopic discectomy vs microdiscectomy. Eur Spine J 2017;26(8):2222.
- Telfeian AE, Veeravagu A, Oyelese AA, et al. A brief history of endoscopic spine surgery. Neurosurg Focus 2016;40(2):E2.
- Narain AS, Hijji FY, Duhancioglu G, et al. Patient perceptions of minimally invasive versus open spine surgery. Clin Spine Surg. 2018;31(3):E184-E192.
- Shamji MF, Goldstein CL, Wang M, et al. Minimally invasive spinal surgery in the elderly: Does it make sense?. Neurosurgery 2015;77 Suppl 4:S108–15.
- Basil GW, Wang MY. Trends in outpatient minimally invasive spine surgery. J Spine Surg 2019;5:S108– S114.