The Learning Curve in Endoscopic Spine Surgery: Global Research Trends, Knowledge Gaps, and Future Directions

Abstract

The learning curve remains one of the most important barriers to the widespread adoption of endoscopic spine surgery. This study aimed to characterize global research trends, influential contributors, knowledge gaps, and future research priorities regarding the learning curve in endoscopic spine surgery through a comprehensive bibliometric analysis.

A bibliometric study was conducted using the Web of Science Core Collection database. Publications related to the learning curve in endoscopic spine surgery were identified through a predefined search strategy. Following manual screening of titles and abstracts, only studies specifically addressing learning curve evaluation were included. Bibliometric indicators including publication trends, countries, authors, journals, keywords, and co-cited references were analyzed using VOSviewer.

Descriptive bibliometric indicators were used to evaluate publication productivity, citation impact, collaboration networks, keyword co-occurrence, and co-citation relationships. Network visualization analyses were performed to identify major research clusters and thematic evolution within the field.

A total of 53 publications were included. Scientific production increased substantially after 2019, reflecting growing interest in endoscopic spine surgery training and proficiency assessment. “Learning curve,” “lumbar disc herniation,” and “percutaneous endoscopic lumbar discectomy” were the most influential keywords. China produced the highest number of publications (n = 26), whereas South Korea demonstrated a disproportionately high citation impact despite a lower publication volume, highlighting its influential role in the development of endoscopic spinal techniques. Co-citation analysis revealed a transition from early technical feasibility studies toward contemporary investigations focused on competency assessment, cumulative sum (CUSUM) methodologies, and surgical performance evaluation. Several areas, including cervical, thoracic, revision, and fusion endoscopic procedures, remain underrepresented in the literature.

Research on the learning curve in endoscopic spine surgery has expanded considerably over the past decade, with increasing emphasis on objective assessment of surgical proficiency. Beyond describing publication patterns, this study identifies important knowledge gaps and emerging priorities, providing a practical roadmap for future research, surgical education, training standardization, and competency-based assessment in endoscopic spine surgery.