A Systematic Review of Complications Associated with Initial Learning Curve of Endoscopic Spine Surgery Highlighting the Necessity of Introducing an Effective Fellowship to Train Competent Endoscopic Spine Surgeons

Background: There is an increase in interest of endoscopic spine surgery as an option of minimally invasive spine surgery. Complications associated with learning curve are a big obstacle to starting a successful endoscopic career. A good endoscopic spine surgery fellowship can mitigate the risk of practice in early phase in endoscopic spine surgery. Methods: We conducted a systematic review in the PubMed database using the terms using three successive searches.10 articles met the criteria of learning curve in endoscopic surgeries evaluation of complications and operation timing. The most consistent parameters used in these studies to evaluate the learning curve were procedure time and complication rate as a function of chronologic case number, our analysis focused on these. The search strategy identified 10 original studies that included 618 endoscopic spine surgery procedures. Results: In the 10 studies, total number of complications was 45 cases (7.2%). 33 cases (5.3%) occurred in the early phase of learning curve. The most frequent reported complications were incomplete decompression (18 cases, 2.9%), incidental durotomies (13 cases; 2.1%), nerve root injuries (11 cases; 1.77%), discitis (2 cases; 0.32% of complications) and hematoma (1 case; 0.16%). The operative time was observed to decrease throughout these case series with no general consensus of number of cases required to reach asymptote. Conclusion: There is steep learning curve with high complications in the initial learning phase of endoscopic spine surgery. It is recommended to have an effective training or fellowship programme to train competent endoscopic spine surgeons.