Minimally Invasive Spine Surgery (2002)

The phrase “minimally invasive spine surgery” is still met with skepticism by most neurosurgeons. In many, it might even elicit overt disbelief or hostility. Indeed, we have been down this path before. We have seen chymopapain come and go, and we have noted the same fate for automated percutaneous lumbar discectomy. We have heard the virtues of laser discectomy, foraminal epidural endoscopic discectomy, and recently intradiscal electrothermy. None of those procedures has been scientifically scrutinized, however, and most have failed to fulfill their initial promises with time. Nevertheless, here we are again, presented with another claim that minimally invasive techniques can achieve excellent clinical results with less patient pain, morbidity, and disability. Is this simply more hype, or is there some reason to think that this time the promises might actually be fulfilled? The phrase “minimally invasive spine surgery” is still met with skepticism by most neurosurgeons. In many, it might even elicit overt disbelief or hostility. Indeed, we have been down this path before. We have seen chymopapain come and go, and we have noted the same fate for automated percutaneous lumbar discectomy. We have heard the virtues of laser discectomy, foraminal epidural endoscopic discectomy, and recently intradiscal electrothermy. None of those procedures has been scientifically scrutinized, however, and most have failed to fulfill their initial promises with time. Nevertheless, here we are again, presented with another claim that minimally invasive techniques can achieve excellent clinical results with less patient pain, morbidity, and disability. Is this simply more hype, or is there some reason to think that this time the promises might actually be fulfilled? This special supplement to Neurosurgery should help the readers analyze the recent data and answer this question for themselves. Reviewing the table of contents points out several significant facts. First, after a few brief introductory comments, of which this is one, the articles are divided into sections relevant to procedures currently being performed at specific anatomic levels. This not only makes it easy for readers to focus rapidly on procedures that are most relevant to their practice but also indicates that the current focus on minimally invasive spine surgery is not limited to a single “trendy” procedure relevant to one pathological process (and often marketed by a single corporate entity). A review of the titles of the articles included in this supplement demonstrates that multiple minimally invasive procedures are being developed, addressing the most common surgical problems at all levels of the spinal axis. Therefore, a “family” of minimally invasive procedures designed to achieve the same technical and clinical results as standard open procedures is evolving. More in-depth analysis of the techniques described reveals another important factor in current minimally invasive procedures. Many, if not most, of the newer procedures being developed do not rely on new and untested technologies to achieve their surgical results. For example, after the surgical target has been reached, procedures such as microendoscopic discectomy, transthoracic endoscopic discectomy, and microendoscopic decompression of stenosis involve the use of standard surgical instruments and techniques. In that respect, “minimally invasive spine surgery” is probably a misnomer. The crucial aspect of the surgical procedure is not minimal at all; it is exactly the same as the equivalent open procedure. However, “minimal access” techniques have been used to access the surgical target. Therefore, “minimal access spine surgery” is probably a more accurate term to describe this family of procedures. Finally, another important point that can be garnered from the articles is that many of these techniques have evolved beyond the necessity to use endoscopes for observation. Modifications enabling the use of a microscope, or even loupes, have eliminated a significant technical hurdle for many surgeons and have made these minimal access techniques available to a broader spectrum of surgeons. In many cases, the only difference between open and minimal access procedures is the substitution of different, less traumatic retraction techniques/systems. The learning curves for these techniques have thus been significantly decreased. Training to master these techniques is still necessary before they can be introduced into the readers’ operating room; however, because the instruments and visual aids are essentially the same as for open procedures, the necessary skills can be acquired much more rapidly. Therefore, although all readers must answer for themselves the question of whether the new techniques represent hype or have real merit, I have my own answer. I think we may be in the early phase of a “concept shift” in how spine surgery is going to be performed. The data reported in this supplement suggest equivalent or better results with minimal access techniques, with decreases in operating times, blood loss, postoperative pain, medication use, hospital stays, and costs. Importantly, these benefits are being achieved with essentially the same operations as we have always performed, but with improved access techniques. One reason why I think we may be in the early phase of a fundamental change in the way we perform spine surgery is demonstrated in Figure 1. This indicates the percentages of spinal procedures that I have performed with open techniques and with minimal access techniques in the past 12 years. Although the types of referrals I receive have not changed, Figure 1 demonstrates that I have progressively changed my techniques; the majority of the surgical procedures I once performed with open techniques I now perform with minimal access techniques. Because the crucial aspects of the surgical procedures are largely the same and patient outcomes are equivalent or better, with patient discomfort and inconvenience being significantly decreased, I think that patients are going to demand these techniques instead of standard open procedures. I consider this position to be quite similar to that observed a decade ago with endoscopic cholecystectomy. FIGURE 1: Open versus minimal access spine procedures performed between 1990 and 2002. MISS, minimally invasive spine surgery.This special supplement would not have been possible without the help and advice of many individuals. I thank Dr. Michael Apuzzo for his foresight in requesting this special edition several years ago, when minimally invasive surgery was even more controversial than it is now. Daniel Sullivan was instrumental in coordinating information transfer among myself, the authors, and the editors of Neurosurgery. My previous fellows, in particular Drs. Larry Khoo, Robert Isaacs, and Mick Perez-Cruet, spent untold hours reviewing manuscripts, as well as writing text for our own contributions. Robin Wellington coordinated the completion of most of the contributions and their delivery to the editors in final form. Finally, my nurses and administrative assistants, Theresa Hall, Laurie Rice-Wyllie, Donna Davis, and Pam Martin, kept all of us on track to coordinate and finish this supplement.