Learning curve of percutaneous transforaminal endoscopic discectomy with visualized foraminoplasty for lumbar spinal stenosis

Objective: This study aims to analyze the learning curve of percutaneous transforaminal endoscopic discectomy (PETD) with visualized foraminoplasty for the treatment of lumbar spinal stenosis (LSS). METHODS 80 patients underwent PETD with visualized foraminoplasty between 1 January 2019 and 1 January 2022 were retrospectively reviewed. Clinical outcomes were evaluated by using the Visual Analogue Scale(VAS) of low back pain(LBP) and leg pain(LP), the Oswestry Disability Index (ODI), and Japanese Orthopaedic Association scores(JOA). The learning curve was assessed by CUSM analysis. According to the learning curve, of these 80 patients were divided into two groups: early group(38) and late group(n = 42) in chronological order for comparison. Results All cases were completed successfully with no conversion to open surgery. No major complications occurred, but 5 patients response to postoperative paresthesia. The mean follow-up time was 16.04 ± 2.62 months. The median operative time reduced from 92.5 (interquartile range(IQR), 80–100) minutes for the early group to 85 (IQR, 80–90) minutes for the late group (P < 0.05). After approximately 38 cases, the curve tends to plateau and is considered a learning plateau. Postoperatively, the VAS of LBP and LP, and ODI in the two groups decreased significantly, the JOA was considerably elevated during the follow-up. The total complication rate was 6.2%. There were no significant differences in ODI, VAS of LP and LBP, JOA and complication rates between the two groups. CLUSIONS PETD with visualized foraminoplasty for LSS performed by surgeons has a notable learning curve. The mastery level could be achieved with 38 cases.