Learning curve of laparoscopic inguinal hernia repair: systematic review, meta-analysis, and meta-regression.

ABSTRACT

BACKGROUND: Laparoscopic inguinal hernia repair has a long learning curve. It can be a technically challenging procedure and initially presents an unfamiliar view of inguinal anatomy. The aim of this review was to evaluate published literature relating to the learning curve of laparoscopic inguinal hernia repair and identify the number of cases required for proficiency. The secondary aim was to compare outcomes between surgeons before and after this learning curve threshold had been attained. METHODS: A systematic literature search was conducted in databases of PubMed, Medline, Embase, Web of Science, and Cochrane Library, to identify studies that evaluated the learning curve of laparoscopic inguinal hernia repair. A meta-regression analysis was undertaken to identify the number of cases to achieve surgical proficiency, and a meta-analysis was performed to compare outcomes between cases that were undertaken during a surgeon's learning phase and experienced phase of the curve. RESULTS: Twenty-two studies were included in this review, with 19 studies included in the meta-regression analysis, and 11 studies included in the meta-analysis. Mixed-effects Poisson regression demonstrated that there was a non-linear trend in the number of cases required to achieve surgical proficiency, with a 2.7% year-on-year decrease. The predicted number of cases to achieve surgical proficiency in 2020 was 32.5 (p < 0.01). The meta-analysis determined that surgeons in their learning phase may experience a higher rate of conversions to open (OR 4.43, 95% CI 1.65, 11.88), postoperative complications (OR 1.61, 95% CI 1.07, 2.42), and recurrences (OR 1.32, 95% CI 0.40, 4.30). CONCLUSION: Laparoscopic inguinal hernia repair has a well-defined learning curve. While learning surgeons demonstrated reasonable outcomes, supervision during this period may be appropriate given the increased risk of conversion to open surgery. These data may benefit learning surgeons in the skill development of minimally invasive inguinal hernia repairs.