Complications in endoscopic spine surgery: a systematic review

Purpose This systematic review aims to investigate the complication rate of endoscopic spine surgeries, stratifying them by technique, district and kind of procedure performed. Methods This study was conducted according to the PRISMA statement. The literature search was conducted in MEDLINE, CINAHL, EMBASE, Cochrane Register, OTseeker and ScienceDirect database. Types of studies included were observational studies (cohort studies, case–control studies and case series) and randomised or quasi-randomised clinical with human subjects. No restrictions on publication year were applied. Repeated articles, reviews, expert's comments, congress abstracts, technical notes and articles not in English were excluded. Several data were extracted from the articles. In particular, data of perioperative (≤ 3 months) and late (> 3 months) complications were collected and grouped according to: (1) surgical technique [uniportal full-endoscopic spine surgery (UESS) or unilateral biportal endoscopic spine surgery (UBESS)]; (2) spinal district treated [cervical, thoracic or lumbar] and (3) type of procedure [discectomy/decompression or fusion]. Complication analysis was performed in subgroups with at least 100 patients to have clinically meaningful statistical validity. Results A total of 117 full-text articles were assessed for eligibility. Of the 117 records included, 95 focused their research on UESS (14 LOE V, 33 LOE IV, 43 LOE III and five LOE II) and 23 on UBESS (three LOE V, eight LOE IV, 10 LOE III and two LOE II). A total of 20,020 patients were extracted to investigate the incidence of different perioperative and late complications, 10,405 for UESS and 9615 for UBESS. Conclusion The present study summarises the complications reported in the literature for spinal endoscopic procedures. On the one hand, the most relevant described were perioperative complications (transient neurological deficit, dural tear and dysesthesia) that are especially meaningful for endoscopic discectomy and decompression. On the other hand, late complications, such as mechanical implant failure, are more common in endoscopic interbody fusion. Level of Evidence I.