The American Academy of Orthopaedic Surgery (AAOS) annual meeting in Chicago from March 22–26 2022, was — for many — the first in-person conference attended since the start of the COVID-19 pandemic. Given the comprehensive nature of the conference for all orthopaedic subspecialities, it was a great surprise to see an instructional course lecture (ICL) dedicated to endoscopic spine surgery (ESS) as well as a few booths in the exhibit hall dedicated to this Minimally Invasive Spine Surgery (MISS) technique. The Academy had previously included ESS in last year’s ICL program, and it seems to be gaining popularity, albeit slowly. Endoscopic techniques have been indicated for degenerative pathology including foraminal stenosis and disc herniation, allowing for direct assessment of nerve decompression and endplate preparation for lumbar interbody fusions. ESS allows surgeons to potentially avoid destabilizing laminotomies or medial facetectomies for select pathologies. While ESS possesses the benefits of MISS including minimal paraspinal structural damage, reduced perioperative pain, and less iatrogenic segmental instability, its widespread adoption has met resistance. Current ESS limitations include two-dimensional visualization impairing depth perception, lack of a preexisting cavity in the spine, and increased radiation exposure for creation of working channels. The ESS procedure is sensitive to small changes in the incision point for interlaminar and transforaminal endoscopic approaches, leading to increased fluoroscopy times, radiation exposure and increased risk for visceral or neurovascular injury. Initially indicated for lumbar disc herniations through a transforaminal route, ESS has expanded indications to thoracic and cervical pathology with the technological advancement in endoscopic equipment and the introduction of new approaches, including an interlaminar approach and biportal approach. Single portal endoscopy housing the endoscope and one surgical instrument creates the least amount of collateral damage but does not allow for independence between camera and instrument making its current use case limited to select pathology. Biportal endoscopy allows for a greater degree of freedom for positioning the scope and instruments via two working channels. However, a lack of a contained joint space makes triangulation and exchanging instruments more challenging in biportal endoscopy.
The highest utilization and growth of ESS is occurring in Asian markets. Challenges to adoption in the U.S. include lack of billing codes supporting ESS, poor reimbursement, and lack of interest from major U.S. medical device manufacturers. In the US, there is a strong incentive to perform fusions and utilize instrumentation. Beyond fiscal challenges, there is a paucity of training centers teaching ESS. Moreover, from the non-endoscopic MISS surgeon’s perspective, the advantage endoscopic approaches provide over a 16mm tubular retractor is speculative. Despite its limitations, ESS is an enabling technology with ergonomic benefits. Furthermore, advancements in technology including robotics, image guidance and navigation may facilitate utilization of ESS.
Dr. Suratwala is employed by Northwell Health, he has no conflicts of interest to report.
Image by DrAfter123 / GettyImages
