Learning Curve Analysis of Single-Incision Laparoscopic Totally Extraperitoneal Inguinal Hernia Repair (SILS-TEP) Among Multiple Surgeons: A Large-Scale CUSUM Evaluation.

INTRODUCTION

Single-incision laparoscopic totally extraperitoneal inguinal hernia repair (SILS-TEP) provides excellent cosmetic outcomes but is technically more demanding than conventional multi-port TEP. Most studies on learning curves focus on single-surgeon experiences. This study aimed to evaluate the collective learning curves of SILS-TEP among multiple experienced gastrointestinal surgeons using cumulative sum (CUSUM) analysis.

METHODS

We retrospectively reviewed 1500 consecutive unilateral SILS-TEP procedures performed by six surgeons (250 cases per surgeon) between May 2021 and December 2025. All surgeons were proficient in general laparoscopic surgery (10-33 years of experience) but were novices in SILS-TEP. Learning curves were analyzed based on operative time using CUSUM analysis. The proficiency threshold was identified, and perioperative outcomes were compared between the learning phase (Phase 1) and the experienced phase (Phase 2).

RESULTS

CUSUM analysis identified a mean proficiency threshold of 95 cases (range: 63-147 cases) across all surgeons. The median operative time significantly decreased from 81 min in Phase 1 to 66 min in Phase 2 (p < 0.0001). While recurrence (0.067%) and overall complication (1.67%) rates remained stable, the incidence of peritoneal injury was significantly lower in Phase 2 compared to Phase 1 (p = 0.0004).

CONCLUSION

The learning curve for SILS-TEP stabilized at an institutional mean of 95 cases under a structured mentoring program. However, individual proficiency thresholds varied notably, ranging from 63 to 147 cases. These findings suggest that while 95 cases serve as a useful institutional benchmark, training programs should remain flexible to accommodate individual surgical learning paces to ensure maximum safety.