Impact of the learning curve of percutaneous endoscopic lumbar discectomy on clinical outcomes: a systematic review

Although it is well-recognized within the endoscopic spine community that a learning curve exists for percu-taneous endoscopic lumbar discectomy (PELD), it is less well understood how the learning curve impacts PELD clinical outcomes. This systematic literature review serves as the most comprehensive and up-to-date resource on this topic. Following a focused literature search, 21 articles on the learning curve for PELD were found, and from those articles, 21 unique clinical outcome metrics were identified. Operative time was the most commonly re-ported clinical outcome metric in this cohort, appearing in 17 studies. There were unanimous findings among the relevant studies that the following clinical outcomes are not affected by the learning curve for PELD: Oswestry Disability Index and herniation rate. Additionally, there were unanimous findings that the following clinical results are affected by the learning curve for PELD: cannula placement time, postoperative dural sac cross-sectional area; fluoroscopy time; and operative time. The purpose of this collection of findings in this system-atic review is to positively inform current and future surgeons and trainees embarking on the learning curve for PELD.