Two experts from the field of spine surgery, Paul Houle (Hyannis, USA) and Jeremy Steinberger (New York, USA), go head-to-head on the controversial topic of whether or not endoscopic surgery will eventually become the standard of care for spinal decompression.
Endoscopic surgery WILL become the standard of care: Paul Houle, endoscopic and minimally invasive spine neurosurgeon at Cape Cod Healthcare (Hyannis, USA)
Change is uncomfortable. Especially for surgeons. We have been taught our craft by titans, who had been taught their craft by their titans, who in turn had been taught their craft by their titans. I can still remember my chairman telling me “we do it the same way every time.” While there is certainly a benefit to this statement, knowledge is not static. As our understanding grows, we must evolve and adapt our techniques to incorporate new knowledge.
Modern lumbar spine surgery began in 1934 with open laminectomy and transdural resection of disc herniations. This technique evolved in 1977 into the microsurgical technique we know today. In the 1990s ‘microendoscopic’ techniques were developed with the promise of reducing morbidity and improving outcome. This desire has forced us to ask the question, “is there a better way?”
It is well described in our literature that the strongest predictor of a good long-term outcome is a good short-term outcome. This is predicted by the efficacy of nerve root decompression and the extent of iatrogenic collateral damage to the paraspinal musculature, facets, ligaments and nerves. The long term outcomes of endoscopic spine surgery (ESS) are identical to tubular or microsurgical techniques, which makes sense since the all three techniques are essential the same, the only difference is the approach. What is different is the collateral damage that occurs with each technique. The markers of inflammation are markedly and statistically significantly reduced when comparing endoscopic to tubular and microdiscectomy. Furthermore, there is a growing body of literature demonstrating the improved short-term outcomes with endoscopic surgery. One only needs to perform a literature search to discover the exponential increase in scientific publications for ESS.
While the science supports ESS its adoption is hindered by dogma within the medical education system and fear of change. There is also the perception that it is a percutaneous technique without visualisation of the neural structures or pathology. In reality, the technique of disc removal is the same, but the approach is different and the instruments are smaller. In China ESS is the standard of care, for the simple reason of lack of resources.
However, what will drive ESS to become the standard here is our patients. They have access to information that previous generations never had. Many patients have already had doctor Google give them their diagnosis and treatment plan. Patients demand minimally invasive surgeries because they perceive it to be better and they are willing to travel to get it. In fact, a publication by Albert Telfeian (Providence, USA) described how far patients were willing to travel to have endoscopic spine surgery—over 1,000 miles!
The past two years of the pandemic demonstrated that many surgical procedures can be performed in an ambulatory care setting. ESS, which is most often performed under conscious sedation with a local anaesthetic is particularly suited for the short perioperative recovery times desired by an ambulatory surgery centre.
We all know that we can find an equal number of studies in the literature for or against any topic. It is clear from the literature that ESS is a safe and effective procedure. What will drive the adoption of ESS is the demand from our patients. Surgeons, especially those in competitive markets, will either learn these techniques or watch their patients find surgeons that do.
Spinal News International recently ran a poll asking physicians whether or not they believed that endoscopic spine surgery would become the standard of care for spinal decompression. The results were as follows:
Endoscopic surgery WILL NOT become the standard of care: Jeremy Steinberger, director of minimally invasive spine surgery at Mount Sinai Health System (New York, USA)
In taking a position in a debate of ‘for’ or ‘against,’ the most common casualty is nuance. So I would like to start by clarifying my nuanced position—endoscopic spine surgery definitely has a future in spine surgery. The applications will continue to grow, improve, and expand, and patients will benefit from this evolution. However, endoscopic will not become the ‘standard of care’ in spinal decompression surgery.
As it stands now, there are three major categories of approach to the lumbar spine for decompression surgery. The first category is ‘traditional open,’ in which a subperiosteal approach to the spine is performed, the muscles and ligaments stripped, and a retractor placed prior to the decompression. Once this is complete, the bone, ligament, and osteophytes compressing the spinal cord, thecal sac, and/or nerves are removed and the neural elements freed. The strength of this approach is that the visualisation is the best of the three approaches with clear visualisation of all relevant structures. The weakness is the damage caused during the approach.
The tubular, minimally invasive decompression was developed to minimise muscle and ligament disruption during the approach for decompression. A dilator is docked into position on the inferior side of the lamina, an X-ray performed to confirm appropriate positioning at the correct level, and sequential dilators are placed to minimise muscle disruption, and a tube is placed (commonly 18mm wide). Through this tube the spinal cord, thecal sac, and nerves are decompressed. This can be done unilaterally or bilaterally with an ‘over the top’ approach. At the conclusion of the surgery, the tube is removed and the muscles return to their orientation. There has been evidence of decreased cost, pain, length of stay, blood loss with this approach1. Other studies have found different results with no difference in outcomes between tubular and open decompressions2.
More recently, percutaneous endoscopic spinal decompression surgery has been gaining significant momentum in the spine surgery community. A stab skin incision is made and an endoscope utilised for visualisation with a portal for decompression instruments. An interlaminar or transforaminal approach can be utilised. Of the three approaches for spine decompression, the visualisation is most limited in this approach but it is also the most ‘minimally invasive’ as the incision is smaller, there is minimal to no muscle disruption, and with the endoscope, there is direct live video footage of the nerves, ligament and bone. There is early evidence supporting successful patient outcomes with this approach.3 4
There is a time and place for different approaches and techniques. There is tremendous subtlety in decision making based on the patient (obese, prior surgery), pathology (central stenosis, subarticular stenosis, herniated disc, far lateral herniated disc, level of pathology, orientation of facets, number of pathologic levels involved), and surgeon experience. Prospective and randomised trials are necessary to prove superiority of one versus the other. Endoscopic spine surgery will continue to be an excellent option in a spine surgeon’s armamentarium, but it will never be standard of care.
References:
1. Clark AJ, Safaee MM, Khan NR, Brown MT, Foley KT. Tubular microdiscectomy: techniques, complication avoidance, and review of the literature. Neurosurg Focus. 2017 Aug;43(2):E7. doi: 10.3171/2017.5.FOCUS17202. PMID: 28760036.
2. Overdevest GM, Peul WC, Brand R, Koes BW, Bartels RH, Tan WF, Arts MP; Leiden-The Hague Spine Intervention Prognostic Study Group. Tubular discectomy versus conventional microdiscectomy for the treatment of lumbar disc herniation: long-term results of a randomised controlled trial. J Neurol Neurosurg Psychiatry. 2017 Dec;88(12):1008-1016. doi: 10.1136/jnnp-2016-315306. Epub 2017 May 26. PMID: 28550071.
3. Liu X, Yuan S, Tian Y, Wang L, Gong L, Zheng Y, Li J. Comparison of percutaneous endoscopic transforaminal discectomy, microendoscopic discectomy, and microdiscectomy for symptomatic lumbar disc herniation: minimum 2-year follow-up results. J Neurosurg Spine. 2018 Mar;28(3):317-325. doi: 10.3171/2017.6.SPINE172. Epub 2018 Jan 5. PMID: 29303471.
4. Yoon SM, Ahn SS, Kim KH, Kim YD, Cho JH, Kim DH. Comparative Study of the Outcomes of Percutaneous Endoscopic Lumbar Discectomy and Microscopic Lumbar Discectomy Using the Tubular Retractor System Based on the VAS, ODI, and SF-36. Korean J Spine. 2012 Sep;9(3):215-22. doi: 10.14245/kjs.2012.9.3.215. Epub 2012 Sep 30. PMID: 25983818; PMCID: PMC4431005.
