[Comparative study of decompression of unilateral biportal endoscopic compared to laminectomy with fusion and internal fixation in the treatment of severe lumbar spinal stenosis].

Objective: To compare the clinical efficacy of unilateral biportal endoscopy unilateral laminotomy for bilateral decompression (UBE-ULBD) to posterior lumbar interbody fusion (PLIF) in the treatment of severe lumbar spinal stenosis (SLSS). Methods: The clinical data of 64 patients with SLSS treated with PLIF and UBE-ULBD in Dalian Central Hospital Affiliated to Dalian Medical University from April 2018 to April 2021 were collected and divided into UBE group and PLIF group according to the different surgical procedures. There were 30 cases in the UBE group, including 12 males and 18 females, aged (69.8±6.8) years. There were 34 patients in the PLIF group, including 15 males and 19 females, aged (69.3±6.3) years. The operation time, intraoperative blood loss, surgical complications, the volume of drainage, transfusion, post-operative bed rest time, postoperative hospital stay, surgical costs of both groups were recorded and analyzed. The visual analogue scales (VAS) of back/leg pain (pre-operation and 1 d, 1 month, 6 month, 12 month post-operation) and Oswestry disability index (ODI) (pre-operation and 1 month, 6 month, 12 month post-operation) were used to determine the outcome. And the dural sac cross-sectional area (DSCA) and Schizas grade of both groups preoperatively and 6 month postoperatively were recorded. Results: The operation time in the UBE group was (69.2±8.0) min, it was lower than that in the PLIF group (139.0±15.3) min (P<0.05). The intraoperative blood loss and drainage in the UBE group were (19.5±5.6) ml and (15.0±10.8) ml, which were both lower than those in the PILF group [(212.4±34.1) ml and (169.6±43.8) ml] (both P<0.05). The postoperative bed rest time and hospital stay in the UBE group were (1.8±0.7) days and (3.0±0.9) days, which were both shorter than those in the PLIF group [(4.5±1.4) days and (7.1±1.7) days] (both P<0.05). The surgical cost was also lower in the UBE group than that in the PLIF group [RMB,(18.4±1.0) thousands yuan vs (33.9±2.4) thousands yuan, P<0.05]. In addition, no patient received blood transfusion in the UBE group. Dural sac tear occurred in 2 cases in the UBE group and in 3 cases in PLIF group; nerve root injury and infection occurred in one case in the PLIF group, respectively. In the PLIF group, the VAS of back pain was not significantly improved 1 day after operation when compared with that before the operation, but it significantly improved 1 month, 6 months and 1 year after operation (all P<0.05). The VAS for back pain at 1 day after operation and ODI at 1 month after operation in the UBE group were significantly superior to those in the PLIF group (both P<0.05), while there was no significant difference between the two groups in the VAS for back pain at 1 month, 6 months and 1 year after operation and ODI at 6 months and 1 year after operation. Both groups got significant canal expansion after the surgery and the PLIF group showed larger canal expansion extent (all P<0.05). Both groups improved significantly after surgery in the Schizas grade, there were 25 cases in UBE group improved to grade A, 5 cases to grade B while 30 cases in PLIF group improved to grade A, 4 cases to grade B, but there was no significant difference between the two groups (P>0.05). Conclusion: ULBD-UBE could achieve full decompression of the whole spinal canal with limited structures damage in treating SLSS. Compared with PLIF, UBE-ULBD could get complete decompression as well as less iatrogenic damage, it may be an ideal alternative surgical technique for SLSS with less invasion.