Learning curve for percutaneous endoscopic lumbar discectomy depending on the surgeon's training level of minimally invasive spine surgery

Purpose: To evaluate the differences of learning curve for PELD depending on the surgeon' s training level of minimally invasive spine surgery. Methods: We retrospectively reviewed the medical records of 120 patients (surgeon A with his first 60 patients, surgeon B with his first 60 patients) with sciatica and single-level L4/5 disk herniation who underwent PELD by the two surgeons with different training level of minimally invasive spine surgery (Group A: surgeon with little professional training of PELD; Group B: surgeon with 2 years of demonstration teaching of PELD). Results: Significant differences were observed in the operation time (p = 0.000), postoperative hospital stay (p = 0.026) and reoperation rate (p = 0.050) between the two groups. In the operation time, significant differences were observed between the 1-20 patients group and 41-60 patients group in Group B (p = 0.041), but there were no significant differences among the 1-20 patients group, 21-40 patients group and 41-60 patients group in Group A. In the postoperative hospital stay, the significant differences were observed in the 1-20 patients group between Group A and Group B (p = 0.011). Significant differences were observed between preoperative and postoperative VAS back score, VAS leg score and JOA score. Higher improvement in the VAS leg score was observed in Group B than Group A (p = 0.031). In the rate of reoperation, the significant difference was observed between the 1-20 patients group and 41-60 patients group in Group A (p = 0.028) but there were no significant differences among the 1-20 patients group, 21-40 patients group and 41-60 patients group in Group B. Conclusions: The surgeons' training level of minimally invasive spine surgery was an important factor for the success of PELD, especially the demonstration teaching of PELD for the new minimally invasive spine surgeons. (C) 2013 Elsevier B.V. All rights reserved.