Dural Sac Cross-sectional area change from preoperatively and up to 2 years after decompressive surgery for central lumbar spinal stenosis: investigation of operated levels, data from the NORDSTEN study.

PURPOSE: The aim of the present study was to investigate how canal area size changed from before surgery and up to 2 years after decompressive lumbar surgery lumbar spinal stenosis. Further, to investigate if an area change postoperatively (between 3 months to 2 years) was associated with any preoperative demographic, clinical or MRI variables or surgical method used. METHODS: The present study is analysis of data from the NORDSTEN- SST trial where 437 patients were randomized to one of three mini-invasive surgical methods for lumbar spinal stenosis. The patients underwent MRI examination of the lumbar spine before surgery, and 3 and 24 months after surgery. For all operated segments the dural sac cross-sectional area (DSCA) was measured in mm2. Baseline factors collected included age, gender, BMI and smoking habits. Furthermore, surgical method, index level, number of levels operated, all levels operated on and baseline Schizas grade were also included in the analysis. RESULTS: 437 patients were enrolled in the NORDSTEN-SST trial, whereof 310 (71%) had MRI at 3 months and 2 years. Mean DSCA at index level was 52.0 mm2 (SD 21.2) at baseline, at 3 months it increased to 117.2 mm2 (SD 43.0) and after 2 years the area was 127.7 mm2 (SD 52.5). Surgical method, level operated on or Schizas did not influence change in DSCA from 3 to 24 months follow-up. CONCLUSION: The spinal canal area after lumbar decompressive surgery for lumbar spinal stenosis increased from baseline to 3 months after surgery and remained thereafter unchanged 2 years postoperatively.

Intraoperative epidural analgesia for pain relief after lumbar decompressive spine surgery: A systematic review and meta-analysis.

Introduction: During lumbar decompressive spine surgery, the epidural space is easily accessible. This intraoperative situation allows surgeons to apply an epidural bolus of analgesia at the end of the surgical procedure. In literature, several papers about the methods and effectiveness of delivering local analgesia during lumbar decompressive spine surgery have been published. Research question: This systematic review and meta-analysis aims to summaries the current literature on the effectiveness and safety of intraoperative epidural analgesia in lumbar decompressive surgery, delivered as a bolus. Material and method: A systematic search was conducted according to the PRISMA guidelines. Inclusion criteria were randomized controlled trials or comparative cohort studies of patients aged 18 years or older who underwent decompressive lumbar spine surgery. Nonsteroidal epidural analgesia had to be administered as a bolus, intraoperatively, as an adjunct to standard analgesia therapy. Primary outcome measures were reduction in postoperative pain scores, analgesics consumption and length of hospital stay. Secondary outcomes were adverse events. Results: Eight studies evaluating the effectiveness of intraoperative epidural analgesia were included. Seven studies reported statistically significant reductions in postoperative VAS-pain scores. Six studies reported a statistically significant decrease in postoperative analgesics consumption. Four studies reported on the length of hospital stay, with no statistically significant difference between study groups. Discussion and conclusion: This systematic review and meta-analysis suggests that additional intraoperative epidural nonsteroidal analgesia, delivered as a bolus, can reduce postoperative pain and postoperative analgesics consumption in patients undergoing decompressive spinal surgery. Further well-powered research is needed to bolster the evidence.